refactor: remove usePdfBurner parameter from AddEnvelopeGeneratorServices

Changed the SendFinalEmailToReceiversAsync method to use a sequential `foreach` loop
instead of `Task.WhenAll` for sending history commands. Added a null check for
receiver emails to prevent potential exceptions.

EnvelopeGenerator.Application.VB/EnvelopeGenerator.Application.VB.vbproj

@@ -0,0 +1,22 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <RootNamespace>EnvelopeGenerator.Application.VB</RootNamespace>
+    <TargetFrameworks>net7.0;net8.0;net9.0</TargetFrameworks>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="DevExpress.Data" Version="21.2.4" />
+    <PackageReference Include="DevExpress.Reporting.Core" Version="21.2.4" />
+    <PackageReference Include="DevExpress.Win" Version="21.2.0" />
+    <PackageReference Include="DevExpress.Xpo" Version="21.2.4" />
+    <PackageReference Include="System.Drawing.Common" Version="7.0.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Update="Reports\rptEnvelopeHistory.vb">
+      <SubType>Component</SubType>
+    </Compile>
+  </ItemGroup>
+
+</Project>

EnvelopeGenerator.Application.VB/Reports/rptEnvelopeHistory.Designer.vb

@@ -320,7 +320,7 @@ Partial Public Class rptEnvelopeHistory
         Me.XrTableCell19.StylePriority.UseBorders = False
         Me.XrTableCell19.StylePriority.UseFont = False
         Me.XrTableCell19.StylePriority.UseForeColor = False
-        Me.XrTableCell19.Text = "Email"
+        Me.XrTableCell19.Text = "EmailAddress"
         Me.XrTableCell19.Weight = 0.11578820509129036R
         '
         'XrTableCell20
@@ -329,7 +329,7 @@ Partial Public Class rptEnvelopeHistory
         Me.XrTableCell20.BorderColor = System.Drawing.Color.Empty
         Me.XrTableCell20.Borders = DevExpress.XtraPrinting.BorderSide.None
         Me.XrTableCell20.Dpi = 254.0!
-        Me.XrTableCell20.ExpressionBindings.AddRange(New DevExpress.XtraReports.UI.ExpressionBinding() {New DevExpress.XtraReports.UI.ExpressionBinding("BeforePrint", "Text", "[Envelope].[User].[Email]")})
+        Me.XrTableCell20.ExpressionBindings.AddRange(New DevExpress.XtraReports.UI.ExpressionBinding() {New DevExpress.XtraReports.UI.ExpressionBinding("BeforePrint", "Text", "[Envelope].[User].[EmailAddress]")})
         Me.XrTableCell20.Font = New System.Drawing.Font("Arial", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
         Me.XrTableCell20.ForeColor = System.Drawing.Color.Black
         Me.XrTableCell20.Multiline = True
@@ -653,7 +653,7 @@ Partial Public Class rptEnvelopeHistory
         'ObjectDataSource1
         '
         Me.ObjectDataSource1.DataMember = "Items"
-        Me.ObjectDataSource1.DataSource = GetType(EnvelopeGenerator.Common.ReportSource)
+        'Me.ObjectDataSource1.DataSource = GetType(EnvelopeGenerator.CommonServices.ReportSource)
         Me.ObjectDataSource1.Name = "ObjectDataSource1"
         '
         'rptEnvelopeHistory

EnvelopeGenerator.Application/Common/Configurations/AuthenticatorParams.cs

@@ -0,0 +1,33 @@
+namespace EnvelopeGenerator.Application.Common.Configurations;
+
+/// <summary>
+/// 
+/// </summary>
+public class AuthenticatorParams
+{
+    /// <summary>
+    /// Default value is 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz01234567890123456789012345678901234567890123456789'
+    /// </summary>
+    public string CharPool { get; init; } = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz01234567890123456789012345678901234567890123456789";
+
+    //TODO: Increase the DefaultTotpSecretKeyLength (e.g. to 32) but make sure that the QR code is generated correctly and can be scanned by the authenticator.
+    /// <summary>
+    /// Default value is 20
+    /// </summary>
+    public int DefaultTotpSecretKeyLength { get; init; } = 20;
+
+    /// <summary>
+    /// Default value is 
+    /// </summary>
+    public string TotpIssuer { get; init; } = "signFlow";
+
+    /// <summary>
+    /// 0 is user email, 1 is secret key and 2 is issuer.
+    /// </summary>
+    public string TotpUrlFormat { get; init; } = "otpauth://totp/{0}?secret={1}&issuer={2}";
+
+    /// <summary>
+    /// Default value is 20.
+    /// </summary>
+    public int TotpQRPixelsPerModule { get; init; } = 20;
+}

EnvelopeGenerator.Application/Common/Configurations/DispatcherParams.cs

@@ -0,0 +1,27 @@
+namespace EnvelopeGenerator.Application.Common.Configurations;
+
+/// <summary>
+/// 
+/// </summary>
+public class DispatcherParams
+{
+    /// <summary>
+    /// Default value is 1
+    /// </summary>
+    public int SendingProfile { get; init; } = 1;
+
+    /// <summary>
+    /// Defalt value is 'DDEnvelopGenerator'
+    /// </summary>
+    public string AddedWho { get; init; } = "DDEnvelopGenerator";
+
+    /// <summary>
+    /// Default value is 202377
+    /// </summary>
+    public int ReminderTypeId { get; init; } = 202377;
+
+    /// <summary>
+    /// Default value is string.Empty
+    /// </summary>
+    public string? EmailAttmt1 { get; init; } = null;
+}

EnvelopeGenerator.Application/Common/Configurations/GdPictureParams.cs

@@ -0,0 +1,12 @@
+namespace EnvelopeGenerator.Application.Common.Configurations;
+
+/// <summary>
+/// 
+/// </summary>
+public class GdPictureParams
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public string License { get; set; } = null!;
+}

EnvelopeGenerator.Application/Common/Configurations/GtxMessagingParams.cs

@@ -1,20 +1,37 @@
-using DigitalData.Core.Abstractions.Client;
-namespace EnvelopeGenerator.Application.Configurations;
+using DigitalData.Core.Client.Interface;
+namespace EnvelopeGenerator.Application.Common.Configurations;
 
 /// <summary>
 /// https://www.gtx-messaging.com/en/api-docs/sms-rest-api/
 /// </summary>
 public class GtxMessagingParams : IHttpClientOptions
 {
+    /// <summary>
+    /// 
+    /// </summary>
     public required string Uri { get; init; }
 
+    /// <summary>
+    /// 
+    /// </summary>
     public string? Path { get; init; }
 
+    /// <summary>
+    /// 
+    /// </summary>
     public Dictionary<string, object>? Headers { get; init; }
 
+    /// <summary>
+    /// 
+    /// </summary>
     public Dictionary<string, object?>? QueryParams { get; init; }
-
+    /// <summary>
+    /// Default value is 'to'
+    /// </summary>
     public string RecipientQueryParamName { get; init; } = "to";
 
+    /// <summary>
+    /// Default value is 'text'
+    /// </summary>
     public string MessageQueryParamName { get; init; } = "text";
 }

EnvelopeGenerator.Application/Common/Configurations/MailParams.cs

@@ -0,0 +1,12 @@
+namespace EnvelopeGenerator.Application.Common.Configurations;
+
+/// <summary>
+/// 
+/// </summary>
+public class MailParams
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public required Dictionary<string, string> Placeholders { get; init; }
+}

EnvelopeGenerator.Application/Common/Configurations/PDFBurnerParams.cs

@@ -0,0 +1,78 @@
+using EnvelopeGenerator.Application.Common.Interfaces.Model;
+using System.Diagnostics.CodeAnalysis;
+using System.Drawing;
+
+namespace EnvelopeGenerator.Application.Common.Configurations;
+
+/// <summary>
+/// 
+/// </summary>
+public class PDFBurnerParams : ITextStyle
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public int ConcurrencyLimit { get; set; } = 5;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public IEnumerable<string> IgnoredLabels { get; set; } = new List<string>
+    {
+        "Date", "Datum", "ZIP", "PLZ", "Place", "Ort", "Position", "Stellung"
+    };
+
+    /// <summary>
+    /// 
+    /// </summary>
+
+    public double TopMargin { get; set; } = 0.1;
+
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public double YOffset { get; set; } = -0.3;
+
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string FontName { get; set; } = "Arial";
+
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int FontSize { get; set; } = 8;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    [SuppressMessage("Interoperability", "CA1416:Validate platform compatibility", Justification = "<Pending>")]
+    public FontStyle FontStyle { get; set; } = FontStyle.Italic;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public Dictionary<string, int> IndexOfAnnot { get; init; } = new()
+    {
+        { string.Empty, 0 },
+        { "seal", 0 },
+        { "position", 1 },
+        { "city", 2 },
+        { "date", 3 }
+    };
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int DefaultIndexOfAnnot { get; set; } = 0;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="name"></param>
+    /// <returns></returns>
+    public int GetAnnotationIndex(string name) => IndexOfAnnot.TryGetValue(name, out var value) ? value : DefaultIndexOfAnnot;
+}

EnvelopeGenerator.Application/Common/Configurations/TotpSmsParams.cs

@@ -0,0 +1,81 @@
+using OtpNet;
+using System.Globalization;
+
+namespace EnvelopeGenerator.Application.Common.Configurations;
+
+/// <summary>
+/// 
+/// </summary>
+public class TotpSmsParams
+{
+    /// <summary>
+    /// The unit is second.
+    /// </summary>
+    public int TotpStep { get; init; } = 90;
+
+    /// <summary>
+    /// Default value is 'Ihr 2FA-Passwort lautet {0}. Gültig bis {1}'
+    /// </summary>
+    public string Format { get; init; } = "Ihr 2FA-Passwort lautet {0}. Gültig bis {1}";
+    
+    /// <summary>
+    /// 
+    /// </summary>
+    public ExpirationHandler Expiration { get; init; } = new();
+
+    /// <summary>
+    /// Default value is VerificationWindow.RfcSpecifiedNetworkDelay
+    /// </summary>
+    public VerificationWindow? TotpVerificationWindow { get; private init; } = VerificationWindow.RfcSpecifiedNetworkDelay;
+
+    private IEnumerable<int>? _tvwParams;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public IEnumerable<int>? TotpVerificationWindowParams
+    {
+        get => _tvwParams;
+        init
+        {
+            _tvwParams = value;
+            if(_tvwParams is not null)
+                TotpVerificationWindow = new(previous: _tvwParams.ElementAtOrDefault(0), future: _tvwParams.ElementAtOrDefault(0));
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public class ExpirationHandler
+    {
+        /// <summary>
+        /// Default value is 'e{0}_r{1}_sms_code_expiration'
+        /// </summary>
+        public string CacheKeyFormat { get; init; } = "e{0}_r{1}_sms_code_expiration";
+
+        /// <summary>
+        /// Default value is HH:mm:ss
+        /// </summary>
+        public string Format { get; init; } = "HH:mm:ss";
+
+        /// <summary>
+        /// Default value is 'de-DE'
+        /// </summary>
+        public string CultureName
+        {
+            get => _cultureInfo.Name;
+            init => _cultureInfo = new(value);
+        }
+
+        /// <summary>
+        /// Default value is 'de-DE'
+        /// </summary>
+        private CultureInfo _cultureInfo = new("de-DE");
+
+        /// <summary>
+        /// Default value is 'de-DE'
+        /// </summary>
+        public CultureInfo CultureInfo => _cultureInfo;
+    }
+}

EnvelopeGenerator.Application/Common/Dto/AnnotationDto.cs

@@ -0,0 +1,73 @@
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// 
+/// </summary>
+public record AnnotationCreateDto
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public int ElementId { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string Name { get; init; } = null!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string Value { get; init; } = null!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string Type { get; init; } = null!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public double? X { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public double? Y { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public double? Width { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public double? Height { get; init; }
+}
+
+/// <summary>
+/// 
+/// </summary>
+public record AnnotationDto : AnnotationCreateDto
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public long Id { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime AddedWhen { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime? ChangedWhen { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? ChangedWho { get; init; }
+}

EnvelopeGenerator.Application/Common/Dto/ConfigDto.cs

@@ -0,0 +1,30 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// Data Transfer Object representing configuration settings.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class ConfigDto
+{
+    /// <summary>
+    /// Gets or sets the sending profile identifier.
+    /// </summary>
+    public int SendingProfile { get; set; }
+
+    /// <summary>
+    /// Gets or sets the signature host URL or name.
+    /// </summary>
+    public required string SignatureHost { get; set; }
+
+    /// <summary>
+    /// Gets or sets the name of the external program.
+    /// </summary>
+    public string? ExternalProgramName { get; set; }
+
+    /// <summary>
+    /// Gets or sets the path where exports will be saved.
+    /// </summary>
+    public string? ExportPath { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/DocumentDto.cs

@@ -0,0 +1,35 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// Data Transfer Object representing a document within an envelope, including optional binary data and form elements.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class DocumentDto
+{
+    /// <summary>
+    /// Gets or sets the unique identifier of the document.
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// Gets or sets the envelope ID to which the document belongs.
+    /// </summary>
+    public int EnvelopeId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the date and time when the document was added.
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the binary data of the document, if available.
+    /// </summary>
+    public byte[]? ByteData { get; set; }
+
+    /// <summary>
+    /// Gets or sets the collection of elements associated with the document for receiver interactions, if any.
+    /// </summary>
+    public IEnumerable<SignatureDto>? Elements { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/DocumentStatusDto.cs

@@ -0,0 +1,51 @@
+using EnvelopeGenerator.Domain.Constants;
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// Data Transfer Object representing the status of a document for a specific receiver.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class DocumentStatusDto
+{
+    /// <summary>
+    /// Gets or sets the unique identifier of the document status entry.
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// Gets or sets the ID of the associated envelope.
+    /// </summary>
+    public int EnvelopeId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the ID of the receiver associated with this status.
+    /// </summary>
+    public int ReceiverId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the current status code.
+    /// </summary>
+    public EnvelopeStatus Status { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when the status was changed.
+    /// </summary>
+    public DateTime? StatusChangedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when this record was added.
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when this record was last changed.
+    /// </summary>
+    public DateTime? ChangedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the display value associated with the status.
+    /// </summary>
+    public string? Value { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/EmailTemplateDto.cs

@@ -1,13 +1,12 @@
-using DigitalData.Core.Abstractions;
-using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc;
 
-namespace EnvelopeGenerator.Application.DTOs
+namespace EnvelopeGenerator.Application.Common.Dto
 {
     /// <summary>
     /// 
     /// </summary>
     [ApiExplorerSettings(IgnoreApi = true)]
-    public record EmailTemplateDto : IUnique<int>
+    public record EmailTemplateDto
     {
         /// <summary>
         /// 

EnvelopeGenerator.Application/Common/Dto/EnvelopeDto.cs

@@ -0,0 +1,121 @@
+using DigitalData.EmailProfilerDispatcher.Abstraction.Attributes;
+using DigitalData.UserManager.Application.DTOs.User;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// 
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public record EnvelopeDto
+{
+	/// <summary>
+	/// 
+	/// </summary>
+	public int Id { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int UserId { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public required EnvelopeStatus Status { get; set; }
+
+    /// <summary>
+    /// Default value is string.Empty
+    /// </summary>
+    public string StatusName { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Default value is string.Empty
+    /// </summary>
+    public string Uuid { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Default value is string.Empty
+    /// </summary>
+    [TemplatePlaceholder("[MESSAGE]")]
+    public string Message { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime? ChangedWhen { get; set; }
+
+    /// <summary>
+    /// Default value is string.Empty
+    /// </summary>
+    [TemplatePlaceholder("[DOCUMENT_TITLE]")]
+    public string Title { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int? ContractType { get; set; }
+
+    /// <summary>
+    /// Default value is 'de-DE'
+    /// </summary>
+    public string Language { get; set; } = "de-DE";
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int? EnvelopeTypeId { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int? CertificationType { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool? UseAccessCode { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool TFAEnabled { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public UserReadDto? User { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public EnvelopeType? EnvelopeType { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? EnvelopeTypeTitle { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool IsAlreadySent { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public byte[]? DocResult { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public IEnumerable<DocumentDto>? Documents { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/EnvelopeReceiver/EnvelopeReceiverDto.cs

@@ -0,0 +1,78 @@
+using DigitalData.EmailProfilerDispatcher.Abstraction.Attributes;
+using EnvelopeGenerator.Application.Common.Dto.Receiver;
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+
+/// <summary>
+/// 
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public record EnvelopeReceiverDto
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public EnvelopeDto? Envelope { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public ReceiverDto? Receiver { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public (int Envelope, int Receiver) Id => (Envelope: EnvelopeId, Receiver: ReceiverId);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int EnvelopeId { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int ReceiverId { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int Sequence { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    [TemplatePlaceholder("[NAME_RECEIVER]")]
+    public string? Name { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? JobTitle { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? CompanyName { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? PrivateMessage { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime AddedWhen { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime? ChangedWhen { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool HasPhoneNumber { get; init; }
+}

EnvelopeGenerator.Application/Common/Dto/EnvelopeReceiver/EnvelopeReceiverSecretDto.cs

@@ -0,0 +1,20 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+
+/// <summary>
+/// 
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public record EnvelopeReceiverSecretDto : EnvelopeReceiverDto
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? AccessCode { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? PhoneNumber { get; init; }
+}

EnvelopeGenerator.Application/Common/Dto/EnvelopeReceiverReadOnly/EnvelopeReceiverReadOnlyCreateDto.cs

@@ -0,0 +1,39 @@
+using Microsoft.AspNetCore.Mvc;
+using System.ComponentModel.DataAnnotations;
+using System.Text.Json.Serialization;
+
+namespace EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly;
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="DateValid"></param>
+[ApiExplorerSettings(IgnoreApi = true)]
+public record EnvelopeReceiverReadOnlyCreateDto(
+    DateTime DateValid)
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    [EmailAddress]
+    [Required]
+    public required string ReceiverMail { get; init; }
+
+    /// <summary>
+    /// Default value is null
+    /// </summary>
+    [JsonIgnore]
+    public long? EnvelopeId { get; set; } = null;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    [JsonIgnore]
+    public string? AddedWho { get; set; }
+
+    /// <summary>
+    /// Default value is DateTime.Now
+    /// </summary>
+    [JsonIgnore]
+    public DateTime AddedWhen { get; } = DateTime.Now;
+};

EnvelopeGenerator.Application/Common/Dto/EnvelopeReceiverReadOnly/EnvelopeReceiverReadOnlyDto.cs

@@ -0,0 +1,64 @@
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Application.Common.Dto.Receiver;
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly;
+
+/// <summary>
+/// Represents a read-only Data Transfer Object (DTO) for an envelope receiver.
+/// Contains information about the receiver, associated envelope, and audit details.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class EnvelopeReceiverReadOnlyDto
+{
+    /// <summary>
+    /// Gets or inits the unique identifier of the envelope receiver.
+    /// </summary>
+    public long Id { get; init; }
+
+    /// <summary>
+    /// Gets or inits the identifier of the associated envelope.
+    /// </summary>
+    public long EnvelopeId { get; init; }
+
+    /// <summary>
+    /// Gets or inits the email address of the receiver.
+    /// </summary>
+    public required string ReceiverMail { get; set; }
+
+    /// <summary>
+    /// Gets or inits the date until which the receiver is valid.
+    /// </summary>
+    public DateTime DateValid { get; set; }
+
+    /// <summary>
+    /// Gets or inits the date and time when the receiver was added.
+    /// </summary>
+    public DateTime AddedWhen { get; init; }
+
+    /// <summary>
+    /// Gets or inits the user who added the receiver.
+    /// Default value is 'unknown'.
+    /// </summary>
+    public string AddedWho { get; init; } = "Unknown";
+
+    /// <summary>
+    /// Gets or inits the associated envelope details.
+    /// </summary>
+    public EnvelopeDto? Envelope { get; set; }
+
+    /// <summary>
+    /// Gets or inits the user who last changed the receiver, if any.
+    /// </summary>
+    public string? ChangedWho { get; set; }
+
+    /// <summary>
+    /// Gets or inits the date and time when the receiver was last changed, if any.
+    /// </summary>
+    public DateTime? ChangedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or inits the associated receiver details.
+    /// </summary>
+    public ReceiverDto? Receiver { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/EnvelopeReceiverReadOnly/EnvelopeReceiverReadOnlyUpdateDto.cs

@@ -0,0 +1,31 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly;
+
+/// <summary>
+/// Data Transfer Object for updating a read-only envelope receiver.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class EnvelopeReceiverReadOnlyUpdateDto
+{
+    /// <summary>
+    /// Gets or sets the unique identifier of the envelope receiver.
+    /// </summary>
+    public long Id { get; init; }
+
+    /// <summary>
+    /// Gets or sets the date when the envelope receiver becomes valid.
+    /// </summary>
+    public DateTime DateValid { get; set; }
+
+    /// <summary>
+    /// Gets or sets the name of the user who made the change.
+    /// Default value is unknown.
+    /// </summary>
+    public string ChangedWho { get; set; } = "Unknown";
+
+    /// <summary>
+    /// Gets or sets the date and time when the change was made.
+    /// </summary>
+    public DateTime ChangedWhen { get; set; } = DateTime.Now;
+}

EnvelopeGenerator.Application/Common/Dto/EnvelopeReportDto.cs

@@ -0,0 +1,44 @@
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// 
+/// </summary>
+public record EnvelopeReportDto
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public int EnvelopeId { get; set; }
+
+    // --- HEAD ---
+    /// <summary>
+    /// 
+    /// </summary>
+    public string HeadUuid { get; set; } = null!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string EnvelopeTitle { get; set; } = string.Empty;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string HeadMessage { get; set; } = null!;
+
+    // --- POSITIONS ---
+    /// <summary>
+    /// 
+    /// </summary>
+    public int ItemStatus { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime? ItemDate { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string ItemUserReference { get; set; } = null!;
+}

EnvelopeGenerator.Application/Common/Dto/EnvelopeTypeDto.cs

@@ -0,0 +1,85 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// Data Transfer Object representing a type of envelope with its configuration settings.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class EnvelopeTypeDto
+{
+    /// <summary>
+    /// Gets or sets the unique identifier of the envelope type.
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// Gets or sets the title of the envelope type.
+    /// </summary>
+    public string Title { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the language code used in this envelope type.
+    /// </summary>
+    public string Language { get; set; } = "de-DE";
+
+    /// <summary>
+    /// Gets or sets the number of days after which the envelope expires.
+    /// </summary>
+    public int? ExpiresDays { get; set; }
+
+    /// <summary>
+    /// Gets or sets the certification type identifier.
+    /// </summary>
+    public int? CertificationType { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether an access code is required.
+    /// </summary>
+    public bool? UseAccessCode { get; set; }
+
+    /// <summary>
+    /// Gets or sets the final email template ID to be sent to the creator.
+    /// </summary>
+    public int? FinalEmailToCreator { get; set; }
+
+    /// <summary>
+    /// Gets or sets the final email template ID to be sent to the receivers.
+    /// </summary>
+    public int? FinalEmailToReceivers { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when this envelope type was added.
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when this envelope type was last changed.
+    /// </summary>
+    public DateTime? ChangedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the number of days before expiry when a warning should be sent.
+    /// </summary>
+    public int? ExpiresWarningDays { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether reminder emails should be sent.
+    /// </summary>
+    public bool? SendReminderEmails { get; set; }
+
+    /// <summary>
+    /// Gets or sets the number of days before the first reminder is sent.
+    /// </summary>
+    public int? FirstReminderDays { get; set; }
+
+    /// <summary>
+    /// Gets or sets the interval in days between reminder emails.
+    /// </summary>
+    public int? ReminderIntervalDays { get; set; }
+
+    /// <summary>
+    /// Gets or sets the contract type associated with the envelope type.
+    /// </summary>
+    public int? ContractType { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/History/HistoryCreateDto.cs

@@ -0,0 +1,32 @@
+namespace EnvelopeGenerator.Application.Common.Dto.History;
+
+/// <summary>
+/// Data Transfer Object for creating a new envelope history record.
+/// </summary>
+public class HistoryCreateDto
+{
+    /// <summary>
+    /// Gets or sets the identifier of the envelope.
+    /// </summary>
+    public int EnvelopeId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the user reference associated with the action.
+    /// </summary>
+    public required string UserReference { get; set; }
+
+    /// <summary>
+    /// Gets or sets the status of the envelope at the time of the action.
+    /// </summary>
+    public int Status { get; set; }
+
+    /// <summary>
+    /// Gets or sets the date and time when the action occurred.
+    /// </summary>
+    public DateTime? ActionDate { get; set; }
+
+    /// <summary>
+    /// Gets or sets an optional comment related to the action.
+    /// </summary>
+    public string? Comment { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/History/HistoryDto.cs

@@ -0,0 +1,74 @@
+using DigitalData.UserManager.Application.DTOs.User;
+using EnvelopeGenerator.Application.Common.Dto.Receiver;
+using EnvelopeGenerator.Domain.Constants;
+
+namespace EnvelopeGenerator.Application.Common.Dto.History;
+
+/// <summary>
+/// Data Transfer Object representing the history of an envelope, including status, sender, receiver, and related metadata.
+/// </summary>
+public record HistoryDto
+{
+    /// <summary>
+    /// Unique identifier for the envelope history entry.
+    /// </summary>
+    public long Id { get; set; }
+
+    /// <summary>
+    /// Identifier of the associated envelope.
+    /// </summary>
+    public int EnvelopeId { get; set; }
+
+    /// <summary>
+    /// Reference string for the user related to this history entry.
+    /// </summary>
+    public required string UserReference { get; set; }
+
+    /// <summary>
+    /// Include code of the envelope at this history point.
+    /// </summary>
+    public EnvelopeStatus Status { get; set; }
+
+    /// <summary>
+    /// Type of reference for this history entry.
+    /// </summary>
+    public ReferenceType ReferenceType => ((int)Status).ToString().FirstOrDefault() switch
+    {
+        '1' => ReferenceType.Sender,
+        '2' => ReferenceType.Receiver,
+        _ => ReferenceType.System,
+    };
+
+    /// <summary>
+    /// Human-readable name of the status.
+    /// </summary>
+    public string? StatusName { get; set; }
+
+    /// <summary>
+    /// Date and time when this history entry was added.
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// Date and time when an action was performed, if applicable.
+    /// </summary>
+    public DateTime? ActionDate { get; set; }
+
+    /// <summary>
+    /// Information about the sender associated with this history entry.
+    /// </summary>
+    public UserCreateDto? Sender { get; set; }
+
+    /// <summary>
+    /// Information about the receiver associated with this history entry.
+    /// </summary>
+    public ReceiverDto? Receiver { get; set; }
+
+    /// <summary>
+    /// Optional comment related to this history entry.
+    /// </summary>
+    public string? Comment { get; set; }
+
+    /// <inheritdoc/>
+    public override int GetHashCode() => Id.GetHashCode();
+};

EnvelopeGenerator.Application/Common/Dto/MappingProfile.cs

@@ -1,13 +1,13 @@
 using AutoMapper;
-using EnvelopeGenerator.Application.DTOs.EnvelopeHistory;
-using EnvelopeGenerator.Application.DTOs.EnvelopeReceiver;
-using EnvelopeGenerator.Application.DTOs.EnvelopeReceiverReadOnly;
-using EnvelopeGenerator.Application.DTOs.Messaging;
-using EnvelopeGenerator.Application.DTOs.Receiver;
-using EnvelopeGenerator.Application.Extensions;
+using EnvelopeGenerator.Application.Common.Dto.History;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly;
+using EnvelopeGenerator.Application.Common.Dto.Messaging;
+using EnvelopeGenerator.Application.Common.Dto.Receiver;
+using EnvelopeGenerator.Application.Common.Extensions;
 using EnvelopeGenerator.Domain.Entities;
 
-namespace EnvelopeGenerator.Application.DTOs;
+namespace EnvelopeGenerator.Application.Common.Dto;
 
 /// <summary>
 /// Represents the AutoMapper profile configuration for mapping between
@@ -23,42 +23,38 @@ public class MappingProfile : Profile
     {
         // Entity to DTO mappings
         CreateMap<Config, ConfigDto>();
-        CreateMap<DocumentReceiverElement, DocumentReceiverElementDto>();
+        CreateMap<Signature, SignatureDto>();
         CreateMap<DocumentStatus, DocumentStatusDto>();
         CreateMap<EmailTemplate, EmailTemplateDto>();
         CreateMap<Envelope, EnvelopeDto>();
-        CreateMap<EnvelopeCertificate, EnvelopeCertificateDto>();
-        CreateMap<EnvelopeDocument, EnvelopeDocumentDto>();
-        CreateMap<Domain.Entities.EnvelopeHistory, EnvelopeHistoryDto>();
-        CreateMap<Domain.Entities.EnvelopeHistory, EnvelopeHistoryCreateDto>();
+        CreateMap<Document, DocumentDto>();
+        CreateMap<Domain.Entities.History, HistoryDto>();
+        CreateMap<Domain.Entities.History, HistoryCreateDto>();
         CreateMap<Domain.Entities.EnvelopeReceiver, EnvelopeReceiverDto>();
         CreateMap<Domain.Entities.EnvelopeReceiver, EnvelopeReceiverSecretDto>();
         CreateMap<EnvelopeType, EnvelopeTypeDto>();
-        CreateMap<Domain.Entities.Receiver, ReceiverReadDto>();
-        CreateMap<Domain.Entities.Receiver, ReceiverCreateDto>();
-        CreateMap<Domain.Entities.Receiver, ReceiverUpdateDto>();
-        CreateMap<UserReceiver, UserReceiverDto>();
+        CreateMap<Domain.Entities.Receiver, ReceiverDto>();
         CreateMap<Domain.Entities.EnvelopeReceiverReadOnly, EnvelopeReceiverReadOnlyDto>();
+        CreateMap<ElementAnnotation, AnnotationDto>();
+        CreateMap<ThirdPartyModule, ThirdPartyModuleDto>();
+        CreateMap<EnvelopeReport, EnvelopeReportDto>();
 
         // DTO to Entity mappings
         CreateMap<ConfigDto, Config>();
-        CreateMap<DocumentReceiverElementDto, DocumentReceiverElement>();
+        CreateMap<SignatureDto, Signature>();
         CreateMap<DocumentStatusDto, DocumentStatus>();
         CreateMap<EmailTemplateDto, EmailTemplate>();
         CreateMap<EnvelopeDto, Envelope>();
-        CreateMap<EnvelopeCertificateDto, EnvelopeCertificate>();
-        CreateMap<EnvelopeDocumentDto, EnvelopeDocument>();
-        CreateMap<EnvelopeHistoryDto, Domain.Entities.EnvelopeHistory>();
-        CreateMap<EnvelopeHistoryCreateDto, Domain.Entities.EnvelopeHistory>();
+        CreateMap<DocumentDto, Document>();
+        CreateMap<HistoryDto, Domain.Entities.History>();
+        CreateMap<HistoryCreateDto, Domain.Entities.History>();
         CreateMap<EnvelopeReceiverDto, Domain.Entities.EnvelopeReceiver>();
         CreateMap<EnvelopeTypeDto, EnvelopeType>();
-        CreateMap<ReceiverReadDto, Domain.Entities.Receiver>().ForMember(rcv => rcv.EnvelopeReceivers, rcvReadDto => rcvReadDto.Ignore());
-        CreateMap<ReceiverCreateDto, Domain.Entities.Receiver>();
-        CreateMap<ReceiverUpdateDto, Domain.Entities.Receiver>();
-        CreateMap<UserReceiverDto, UserReceiver>();
-        CreateMap<EnvelopeReceiverBase, EnvelopeReceiverBasicDto>();
+        CreateMap<ReceiverDto, Domain.Entities.Receiver>().ForMember(rcv => rcv.EnvelopeReceivers, rcvReadDto => rcvReadDto.Ignore());
         CreateMap<EnvelopeReceiverReadOnlyCreateDto, Domain.Entities.EnvelopeReceiverReadOnly>();
         CreateMap<EnvelopeReceiverReadOnlyUpdateDto, Domain.Entities.EnvelopeReceiverReadOnly>();
+        CreateMap<AnnotationCreateDto, ElementAnnotation>()
+            .ForMember(dest => dest.AddedWhen, opt => opt.MapFrom(_ => DateTime.UtcNow));
 
         // Messaging mappings
         // for GTX messaging

EnvelopeGenerator.Application/Common/Dto/Messaging/GtxMessagingResponse.cs

@@ -0,0 +1,9 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto.Messaging;
+
+/// <summary>
+/// 
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class GtxMessagingResponse : Dictionary<string, object?> { }

EnvelopeGenerator.Application/Common/Dto/Messaging/SmsResponse.cs

@@ -0,0 +1,25 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto.Messaging;
+
+/// <summary>
+/// 
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public record SmsResponse
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public required bool Ok { get; init; }
+
+    /// <summary>
+    /// Returns !Ok
+    /// </summary>
+    public bool Failed => !Ok;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public dynamic? Errors { get; init; }
+}

EnvelopeGenerator.Application/Common/Dto/PSPDFKitInstant/Annotation.cs

@@ -0,0 +1,122 @@
+using EnvelopeGenerator.Application.Exceptions;
+
+namespace EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+
+/// <summary>
+/// 
+/// </summary>
+public class Annotation
+{
+    private string? _id;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int EnvelopeId { get; private set; } = 0;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int ReceiverId { get; private set; } = 0;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int Index { get; private set; } = 0;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string EgName { get; private set; } = string.Empty;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool HasStructuredID { get; private set; } = false;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool IsLabel
+    {
+        get
+        {
+            if (string.IsNullOrEmpty(EgName))
+                return false;
+
+            var parts = EgName.Split('_');
+            return parts.Length > 1 && parts[1] == "label";
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? Id
+    {
+        get => _id;
+        set
+        {
+            _id = value;
+
+            if (string.IsNullOrWhiteSpace(value))
+                throw new BurnAnnotationException("The identifier of annotation is null or empty.");
+
+            var parts = value.Split('#');
+
+            if (parts.Length != 4)
+                return;
+            // throw new BurnAnnotationException($"The identifier of annotation has more or less than 4 sub-part. Id: {_id}");
+
+            if (!int.TryParse(parts[0], out int envelopeId))
+                throw new BurnAnnotationException($"The envelope ID of annotation is not integer. Id: {_id}");
+            EnvelopeId = envelopeId;
+
+            if (!int.TryParse(parts[1], out int receiverId))
+                throw new BurnAnnotationException($"The receiver ID of annotation is not integer. Id: {_id}");
+            ReceiverId = receiverId;
+
+            if (!int.TryParse(parts[2], out int index))
+                throw new BurnAnnotationException($"The index of annotation is not integer. Id: {_id}");
+            Index = index;
+
+            EgName = parts[3];
+            HasStructuredID = true;
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public List<double>? Bbox { get; set; }
+    
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? Type { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool IsSignature { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? ImageAttachmentId { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public Lines? Lines { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int PageIndex { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? StrokeColor { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/PSPDFKitInstant/Attachment.cs

@@ -0,0 +1,8 @@
+namespace EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="Binary"></param>
+/// <param name="ContentType"></param>
+public record Attachment(string Binary, string ContentType);

EnvelopeGenerator.Application/Common/Dto/PSPDFKitInstant/FormFieldValue.cs

@@ -0,0 +1,8 @@
+namespace EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="Name"></param>
+/// <param name="Value"></param>
+public record FormFieldValue(string Name, string? Value = null);

EnvelopeGenerator.Application/Common/Dto/PSPDFKitInstant/Ink.cs

@@ -0,0 +1,8 @@
+namespace EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="Lines"></param>
+/// <param name="StrokeColor"></param>
+public record Ink(Lines Lines, string? StrokeColor = null);

EnvelopeGenerator.Application/Common/Dto/PSPDFKitInstant/InstantData.cs

@@ -0,0 +1,50 @@
+namespace EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+
+/// <summary>
+/// 
+/// </summary>
+public class InstantData
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public List<Annotation>? Annotations { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public IEnumerable<List<Annotation>>? AnnotationsByReceiver
+    {
+        get
+        {
+            return Annotations?
+                .Where(a => a.HasStructuredID)
+                .GroupBy(a => a.ReceiverId)
+                .Select(g => g.ToList());
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public IEnumerable<List<Annotation>>? UnstructuredAnnotations
+    {
+        get
+        {
+            return Annotations?
+                .Where(a => !a.HasStructuredID)
+                .GroupBy(a => a.ReceiverId)
+                .Select(g => g.ToList());
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public Dictionary<string, Attachment>? Attachments { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public List<FormFieldValue>? FormFieldValues { get; set; }
+}

EnvelopeGenerator.Application/Common/Dto/PSPDFKitInstant/Lines.cs

@@ -0,0 +1,7 @@
+namespace EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="Points"></param>
+public record Lines(List<List<List<float>>> Points);

EnvelopeGenerator.Application/Common/Dto/Receiver/ReceiverDto.cs

@@ -0,0 +1,63 @@
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+using Microsoft.AspNetCore.Mvc;
+using System.Text.Json.Serialization;
+
+namespace EnvelopeGenerator.Application.Common.Dto.Receiver;
+
+/// <summary>
+/// 
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class ReceiverDto
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public required string EmailAddress { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public required string Signature { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    [JsonIgnore]
+    public string? TotpSecretkey { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    [JsonIgnore]
+    public IEnumerable<EnvelopeReceiverDto>? EnvelopeReceivers { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? LastUsedName => EnvelopeReceivers?.LastOrDefault()?.Name;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime? TfaRegDeadline { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <returns></returns>
+    public override int GetHashCode()
+    {
+        return Id.GetHashCode();
+    }
+}

EnvelopeGenerator.Application/Common/Dto/SignatureDto.cs

@@ -0,0 +1,96 @@
+using EnvelopeGenerator.Domain.Interfaces;
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// Data Transfer Object representing a positioned element assigned to a document receiver.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+public class SignatureDto : ISignature
+{
+    /// <summary>
+    /// Gets or sets the unique identifier of the element.
+    /// </summary>
+    public int Id { get; set; }
+
+    /// <summary>
+    /// Gets or sets the identifier of the associated document.
+    /// </summary>
+    public int DocumentId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the identifier of the receiver.
+    /// </summary>
+    public int ReceiverId { get; set; }
+
+    /// <summary>
+    /// Gets or sets the type of the element.
+    /// </summary>
+    public int ElementType { get; set; }
+
+    /// <summary>
+    /// Gets or sets the X coordinate of the element.
+    /// </summary>
+    public double X { get; set; }
+
+    /// <summary>
+    /// Gets or sets the Y coordinate of the element.
+    /// </summary>
+    public double Y { get; set; }
+
+    /// <summary>
+    /// Gets or sets the width of the element.
+    /// </summary>
+    public double Width { get; set; }
+
+    /// <summary>
+    /// Gets or sets the height of the element.
+    /// </summary>
+    public double Height { get; set; }
+
+    /// <summary>
+    /// Gets or sets the page number where the element appears.
+    /// </summary>
+    public int Page { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether the element is required.
+    /// </summary>
+    public bool Required { get; set; }
+
+    /// <summary>
+    /// Gets or sets the tooltip text for the element.
+    /// </summary>
+    public string? Tooltip { get; set; }
+
+    /// <summary>
+    /// Gets or sets a value indicating whether the element is read-only.
+    /// </summary>
+    public bool ReadOnly { get; set; }
+
+    /// <summary>
+    /// Gets or sets the annotation index for ordering or reference.
+    /// </summary>
+    public int AnnotationIndex { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when the element was added.
+    /// </summary>
+    public DateTime AddedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timestamp when the element was last changed, if applicable.
+    /// </summary>
+    public DateTime? ChangedWhen { get; set; }
+
+    /// <summary>
+    /// Gets or sets the top position of the element (in layout terms).
+    /// </summary>
+    public double Top => Y;
+
+    /// <summary>
+    /// Gets or sets the left position of the element (in layout terms).
+    /// </summary>
+    public double Left => X;
+}

EnvelopeGenerator.Application/Common/Dto/ThirdPartyModuleDto.cs

@@ -0,0 +1,57 @@
+namespace EnvelopeGenerator.Application.Common.Dto;
+
+/// <summary>
+/// 
+/// </summary>
+public record ThirdPartyModuleDto
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public int Id { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool Active { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string Name { get; init; } = default!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? Description { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string License { get; init; } = default!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string Version { get; init; } = default!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? AddedWho { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime? AddedWhen { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string? ChangedWho { get; init; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public DateTime? ChangedWhen { get; init; }
+}

EnvelopeGenerator.Application/Common/EnvelopeFlag.cs

@@ -0,0 +1,27 @@
+namespace EnvelopeGenerator.Application.Common;
+
+/// <summary>
+/// 
+/// </summary>
+public enum EnvelopeFlag
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    EnvelopeOrReceiverNonexists,
+
+    /// <summary>
+    /// 
+    /// </summary>
+    NonDecodableEnvelopeReceiverId,
+
+    /// <summary>
+    /// 
+    /// </summary>
+    WrongEnvelopeReceiverId,
+
+    /// <summary>
+    /// 
+    /// </summary>
+    AccessCodeNull
+}

EnvelopeGenerator.Application/Common/Extensions/CacheExtensions.cs

@@ -0,0 +1,222 @@
+using Microsoft.Extensions.Caching.Distributed;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class CacheExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="value"></param>
+    /// <param name="options"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static Task SetLongAsync(this IDistributedCache cache, string key, long value, DistributedCacheEntryOptions? options = null, CancellationToken cToken = default)
+        => options is null
+            ? cache.SetAsync(key, BitConverter.GetBytes(value), token: cToken)
+            : cache.SetAsync(key, BitConverter.GetBytes(value), options: options, token: cToken);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static async Task<long?> GetLongAsync(this IDistributedCache cache, string key, CancellationToken cToken = default)
+    {
+        var value = await cache.GetAsync(key, cToken);
+        return value is null ? null : BitConverter.ToInt64(value, 0);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="value"></param>
+    /// <param name="options"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static Task SetDateTimeAsync(this IDistributedCache cache, string key, DateTime value, DistributedCacheEntryOptions? options = null, CancellationToken cToken = default)
+        => cache.SetLongAsync(key: key, value: value.Ticks, options: options, cToken: cToken);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static async Task<DateTime?> GetDateTimeAsync(this IDistributedCache cache, string key, CancellationToken cToken = default)
+    {
+        var value = await cache.GetAsync(key, cToken);
+        return value is null ? null : new(BitConverter.ToInt64(value, 0));
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="value"></param>
+    /// <param name="options"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static Task SetTimeSpanAsync(this IDistributedCache cache, string key, TimeSpan value, DistributedCacheEntryOptions? options = null, CancellationToken cToken = default)
+        => cache.SetLongAsync(key: key, value: value.Ticks, options: options, cToken);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static async Task<TimeSpan?> GetTimeSpanAsync(this IDistributedCache cache, string key, CancellationToken cToken = default)
+    {
+        var value = await cache.GetAsync(key, cToken);
+        return value is null ? null : new(BitConverter.ToInt64(value, 0));
+    }
+
+    //TODO: use code generator
+    #region GetOrSetAsync
+
+    #region string
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="factory"></param>
+    /// <param name="options"></param>
+    /// <param name="cacheInBackground"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static async Task<string> GetOrSetAsync(this IDistributedCache cache, string key, Func<string> factory, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
+    {
+        var value = await cache.GetStringAsync(key, cToken);
+        if (value is null)
+        {
+            // create new and save
+            value = factory();
+
+            Task CacheAsync() => options is null
+                    ? cache.SetStringAsync(key, value, cToken)
+                    : cache.SetStringAsync(key, value, options, cToken);
+
+            if (cacheInBackground)
+                _ = Task.Run(async () => await CacheAsync(), cToken);
+            else
+                await CacheAsync();
+        }
+
+        return value;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="factoryAsync"></param>
+    /// <param name="options"></param>
+    /// <param name="cacheInBackground"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static async Task<string> GetOrSetAsync(this IDistributedCache cache, string key, Func<Task<string>> factoryAsync, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
+    {
+        var value = await cache.GetStringAsync(key, cToken);
+        if(value is null)
+        {
+            // create new and save
+            value = await factoryAsync();
+
+            Task CacheAsync() => options is null
+                ? cache.SetStringAsync(key: key, value: value, token: cToken)
+                : cache.SetStringAsync(key: key, value: value, options: options, token: cToken);
+
+            if (cacheInBackground)
+                _ = Task.Run(async () => await CacheAsync(), cToken);
+            else
+                await CacheAsync();
+        }
+
+        return value;
+    }
+    #endregion
+
+    #region DateTime
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="factory"></param>
+    /// <param name="options"></param>
+    /// <param name="cacheInBackground"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static async Task<DateTime> GetOrSetAsync(this IDistributedCache cache, string key, Func<DateTime> factory, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
+    {
+        if (await cache.GetDateTimeAsync(key, cToken) is DateTime dateTimeValue)
+            return dateTimeValue;
+        else
+        {
+            // create new and save
+            var newValue = factory();
+
+            Task CacheAsync() => options is null
+                    ? cache.SetDateTimeAsync(key, newValue, cToken: cToken)
+                    : cache.SetDateTimeAsync(key, newValue, options, cToken);
+
+            if (cacheInBackground)
+                _ = Task.Run(async () => await CacheAsync(), cToken);
+            else
+                await CacheAsync();
+
+            return newValue;
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="cache"></param>
+    /// <param name="key"></param>
+    /// <param name="factory"></param>
+    /// <param name="options"></param>
+    /// <param name="cacheInBackground"></param>
+    /// <param name="cToken"></param>
+    /// <returns></returns>
+    public static async Task<DateTime> GetOrSetAsync(this IDistributedCache cache, string key, Func<Task<DateTime>> factory, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
+    {
+        if (await cache.GetDateTimeAsync(key, cToken) is DateTime dateTimeValue)
+            return dateTimeValue;
+        else
+        {
+            // create new and save
+            var newValue = await factory();
+
+            Task CacheAsync() => options is null
+                    ? cache.SetDateTimeAsync(key, newValue, cToken: cToken)
+                    : cache.SetDateTimeAsync(key, newValue, options, cToken);
+
+            if (cacheInBackground)
+                _ = Task.Run(async () => await CacheAsync(), cToken);
+            else
+                await CacheAsync();
+
+            return newValue;
+        }
+    }
+    #endregion
+
+    #endregion
+}

EnvelopeGenerator.Application/Common/Extensions/DecodingExtensions.cs

@@ -0,0 +1,182 @@
+using EnvelopeGenerator.Domain.Constants;
+using System.Text;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class DecodingExtensions
+{
+    /// <summary>
+    /// Validates whether a given string is a correctly formatted Base-64 encoded string.
+    /// </summary>
+    /// <remarks>
+    /// This method checks the string for proper Base-64 formatting, which includes validating
+    /// the length of the string (must be divisible by 4). It also checks each character to ensure
+    /// it belongs to the Base-64 character set (A-Z, a-z, 0-9, '+', '/', and '=' for padding).
+    /// The method ensures that padding characters ('=') only appear at the end of the string and
+    /// are in a valid configuration (either one '=' at the end if the string's length % 4 is 3,
+    /// or two '==' if the length % 4 is 2).
+    /// </remarks>
+    /// <param name="input">The Base-64 encoded string to validate.</param>
+    /// <returns>
+    /// <c>true</c> if the string is a valid Base-64 encoded string; otherwise, <c>false</c>.
+    /// </returns>
+    /// <example>
+    /// <code>
+    /// string testString = "TWFuIGlzIGRpc3Rpbmd1aXNoZWQsIG5vdCBvbmx5IGJ5IGhpcyByZWFzb24sIGJ1dCBieSB0aGlzIHNpbmd1bGFyIHBhc3Npb24gZnJvbSBvdGhlciBhbmltYWxzLCB3aGljaCBpcyBhIGx1c3Qgb2YgdGhlIG1pbmQsIHRoYXQgYnk=";
+    /// bool isValid = IsValidBase64String(testString);
+    /// Console.WriteLine(isValid); // Output: true
+    /// </code>
+    /// </example>
+    public static bool IsBase64String(this string input)
+    {
+        // Check if the string is null or empty
+        if (string.IsNullOrEmpty(input))
+        {
+            return false;
+        }
+
+        // Replace valid base-64 padding
+        input = input.Trim();
+        int mod4 = input.Length % 4;
+        if (mod4 > 0)
+        {
+            // Base-64 string lengths should be divisible by 4
+            return false;
+        }
+
+        // Check each character to ensure it is valid base-64
+        foreach (char c in input)
+        {
+            if (!char.IsLetterOrDigit(c) && c != '+' && c != '/' && c != '=')
+            {
+                // Invalid character detected
+                return false;
+            }
+        }
+
+        // Ensure no invalid padding scenarios exist
+        if (input.EndsWith("==") && input.Length % 4 == 0 ||
+            input.EndsWith("=") && input.Length % 4 == 3)
+        {
+            return true;
+        }
+
+        return input.IndexOf('=') == -1; // No padding allowed except at the end
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="encodedKey"></param>
+    /// <param name="decodedKeys"></param>
+    /// <returns></returns>
+    public static bool TryDecode(this string encodedKey, out string[] decodedKeys)
+    {
+        try
+        {
+            byte[] bytes = Convert.FromBase64String(encodedKey);
+            string decodedString = Encoding.UTF8.GetString(bytes);
+            decodedKeys = decodedString.Split(new string[] { "::" }, StringSplitOptions.None);
+            return true;
+        }
+        catch(ArgumentNullException) { }
+        catch (FormatException) { }
+        catch(ArgumentException) { }
+
+        decodedKeys = Array.Empty<string>();
+        return false;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="decodedKeys"></param>
+    /// <returns></returns>
+    public static EncodeType GetEncodeType(this string[] decodedKeys) => decodedKeys.Length switch
+    {
+        2 => EncodeType.EnvelopeReceiver,
+        3 => long.TryParse(decodedKeys[1], out var _) ? EncodeType.EnvelopeReceiverReadOnly : EncodeType.Undefined,
+        _ => EncodeType.Undefined,
+    };
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="decodedKeys"></param>
+    /// <returns></returns>
+    /// <exception cref="InvalidOperationException"></exception>
+    public static (string? EnvelopeUuid, string? ReceiverSignature) ParseEnvelopeReceiverId(this string[] decodedKeys)
+        => decodedKeys.GetEncodeType() == EncodeType.EnvelopeReceiver
+        ? (EnvelopeUuid: decodedKeys[0], ReceiverSignature: decodedKeys[1])
+        : throw new InvalidOperationException("Attempted to convert a decoded other than type EnvelopeReceiver to EnvelopeReceiver.");
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="decodedKeys"></param>
+    /// <returns></returns>
+    /// <exception cref="InvalidOperationException"></exception>
+    public static long ParseReadOnlyId(this string[] decodedKeys)
+        => decodedKeys.GetEncodeType() == EncodeType.EnvelopeReceiverReadOnly
+        ? long.Parse(decodedKeys[1])
+        : throw new InvalidOperationException("Attempted to convert a decoded other than type EnvelopeReceiver to EnvelopeReceiver. ");
+
+    /// <summary>
+    /// Decodes the envelope receiver ID and extracts the envelope UUID and receiver signature.
+    /// </summary>
+    /// <param name="envelopeReceiverId">The base64 encoded string containing the envelope UUID and receiver signature.</param>
+    /// <returns>A tuple containing the envelope UUID and receiver signature.</returns>
+    public static (string? EnvelopeUuid, string? ReceiverSignature) DecodeEnvelopeReceiverId(this string envelopeReceiverId)
+    {
+        if (!envelopeReceiverId.IsBase64String())
+        {
+            return (null, null);
+        }
+        byte[] bytes = Convert.FromBase64String(envelopeReceiverId);
+        string decodedString = Encoding.UTF8.GetString(bytes);
+        string[] parts = decodedString.Split(new string[] { "::" }, StringSplitOptions.None);
+
+        if (parts.Length > 1)
+            return (EnvelopeUuid: parts[0], ReceiverSignature: parts[1]);
+        else
+            return (string.Empty, string.Empty);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeReceiverReadOnlyId"></param>
+    /// <returns></returns>
+    public static long? DecodeEnvelopeReceiverReadOnlyId(this string envelopeReceiverReadOnlyId)
+    {
+        if (!envelopeReceiverReadOnlyId.IsBase64String())
+        {
+            return null;
+        }
+        byte[] bytes = Convert.FromBase64String(envelopeReceiverReadOnlyId);
+        string decodedString = Encoding.UTF8.GetString(bytes);
+        string[] parts = decodedString.Split(new string[] { "::" }, StringSplitOptions.None);
+
+        if (parts.Length > 2)
+            return long.TryParse(parts[1], out long readOnlyId) ? readOnlyId : null;
+        else
+            return null;
+    }
+
+    /// <summary>
+    /// Gets the envelope UUID from the decoded envelope receiver ID.
+    /// </summary>
+    /// <param name="envelopeReceiverId">The base64 encoded string to decode.</param>
+    /// <returns>The envelope UUID.</returns>
+    public static string? GetEnvelopeUuid(this string envelopeReceiverId) => envelopeReceiverId.DecodeEnvelopeReceiverId().EnvelopeUuid;
+
+    /// <summary>
+    /// Gets the receiver signature from the decoded envelope receiver ID.
+    /// </summary>
+    /// <param name="envelopeReceiverId">The base64 encoded string to decode.</param>
+    /// <returns>The receiver signature.</returns>
+    public static string? GetReceiverSignature(this string envelopeReceiverId) => envelopeReceiverId.DecodeEnvelopeReceiverId().ReceiverSignature;
+}

EnvelopeGenerator.Application/Common/Extensions/EncodingExtensions.cs

@@ -0,0 +1,38 @@
+using System.Text;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// Provides extension methods for decoding and extracting information from an envelope receiver ID.
+/// </summary>
+public static class EncodingExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="readOnlyId"></param>
+    /// <returns></returns>
+    public static string ToEnvelopeKey(this long readOnlyId)
+    {
+        //The random number is used as a salt to increase security but it is not saved in the database.
+        string combinedString = $"{Random.Shared.Next()}::{readOnlyId}::{Random.Shared.Next()}";
+        byte[] bytes = Encoding.UTF8.GetBytes(combinedString);
+        string base64String = Convert.ToBase64String(bytes);
+
+        return base64String;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="input"></param>
+    /// <returns></returns>
+    public static string ToEnvelopeKey(this (string envelopeUuid, string receiverSignature) input)
+    {
+        string combinedString = $"{input.envelopeUuid}::{input.receiverSignature}";
+        byte[] bytes = Encoding.UTF8.GetBytes(combinedString);
+        string base64String = Convert.ToBase64String(bytes);
+
+        return base64String;
+    }
+}

EnvelopeGenerator.Application/Common/Extensions/GdPictureExtensions.cs

@@ -0,0 +1,176 @@
+using EnvelopeGenerator.Application.Common.Dto.PSPDFKitInstant;
+using EnvelopeGenerator.Domain.Constants;
+using GdPicture14;
+using Microsoft.Extensions.Logging;
+using Newtonsoft.Json;
+using SixLabors.ImageSharp;
+using System.Drawing;
+using EnvelopeGenerator.Application.Common.Extensions;
+using EnvelopeGenerator.Application.Common.Interfaces.Model;
+using EnvelopeGenerator.Application.Common.Configurations;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class GdPictureExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="x"></param>
+    /// <param name="y"></param>
+    /// <param name="width"></param>
+    /// <param name="height"></param>
+    /// <param name="page"></param>
+    /// <param name="value"></param>
+    /// <param name="textStyle"></param>
+    public static void AddFormFieldValue(this AnnotationManager manager, double x, double y, double width, double height, int page, string value, ITextStyle textStyle)
+    {
+        manager.SelectPage(page);
+
+        // Add the text annotation
+        var ant = manager.AddTextAnnot((float)x, (float)y, (float)width, (float)height, value);
+
+        // Set the font properties
+        ant.FontName = textStyle.FontName;
+        ant.FontSize = textStyle.FontSize;
+        ant.FontStyle = textStyle.FontStyle;
+
+        manager.SaveAnnotationsToPage();
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="pAnnotation"></param>
+    /// <param name="formFieldValue"></param>
+    /// <param name="options"></param>
+    public static void AddFormFieldValue(this AnnotationManager manager, Annotation pAnnotation, FormFieldValue formFieldValue, PDFBurnerParams options)
+    {
+        var ffIndex = options.GetAnnotationIndex(pAnnotation.EgName);
+
+        // Convert pixels to Inches
+        var oBounds = pAnnotation.Bbox?.Select(points => points.ToInches()).ToList();
+
+        if (oBounds is null || oBounds.Count < 4)
+            return;
+
+        double oX = oBounds[0];
+        double oY = oBounds[1] + options.YOffset * ffIndex + options.TopMargin;
+        double oWidth = oBounds[2];
+        double oHeight = oBounds[3];
+
+        manager.SelectPage(pAnnotation.PageIndex + 1);
+
+        // Add the text annotation
+        var ant = manager.AddTextAnnot((float)oX, (float)oY, (float)oWidth, (float)oHeight, formFieldValue.Value);
+
+        // Set the font properties
+        ant.FontName = options.FontName;
+        ant.FontSize = options.FontSize;
+        ant.FontStyle = options.FontStyle;
+
+        manager.SaveAnnotationsToPage();
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="x"></param>
+    /// <param name="y"></param>
+    /// <param name="width"></param>
+    /// <param name="height"></param>
+    /// <param name="page"></param>
+    /// <param name="base64"></param>
+    public static void AddImageAnnotation(this AnnotationManager manager, double x, double y, double width, double height, int page, string base64)
+    {
+        manager.SelectPage(page);
+        manager.AddEmbeddedImageAnnotFromBase64(base64, (float)x, (float)y, (float)width, (float)height);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="pAnnotation"></param>
+    /// <param name="pAttachments"></param>
+    public static void AddImageAnnotation(this AnnotationManager manager, Annotation pAnnotation, Dictionary<string, Attachment> pAttachments)
+    {
+        var oAttachment = pAttachments
+            .Where(a => a.Key == pAnnotation.ImageAttachmentId)
+            .SingleOrDefault();
+
+        if (oAttachment.Value == null)
+            return;
+
+        // Convert pixels to Inches
+        var oBounds = pAnnotation.Bbox?.Select(post => post.ToInches()).ToList();
+
+        if (oBounds is null || oBounds.Count < 4)
+            return;
+
+        var oX = oBounds[0];
+        var oY = oBounds[1];
+        var oWidth = oBounds[2];
+        var oHeight = oBounds[3];
+
+        manager.SelectPage(pAnnotation.PageIndex + 1);
+        manager.AddEmbeddedImageAnnotFromBase64(oAttachment.Value.Binary, (float)oX, (float)oY, (float)oWidth, (float)oHeight);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="page"></param>
+    /// <param name="value"></param>
+    public static void AddInkAnnotation(this AnnotationManager manager, int page, string value)
+    {
+        var ink = JsonConvert.DeserializeObject<Ink>(value);
+
+        var oSegments = ink?.Lines.Points;
+        var oColor = ColorTranslator.FromHtml(ink?.StrokeColor ?? "#000000");
+        manager.SelectPage(page);
+
+        if (oSegments is null)
+            return;
+
+        foreach (var oSegment in oSegments)
+        {
+            var oPoints = oSegment
+                .Select(points => points.ToPointF())
+                .ToArray();
+
+            manager.AddFreeHandAnnot(oColor, oPoints);
+        }
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="manager"></param>
+    /// <param name="pAnnotation"></param>
+    public static void AddInkAnnotation(this AnnotationManager manager, Annotation pAnnotation)
+    {
+        var oSegments = pAnnotation.Lines?.Points;
+        var oColor = ColorTranslator.FromHtml(pAnnotation.StrokeColor ?? "#000000");
+        manager.SelectPage(pAnnotation.PageIndex + 1);
+
+        if (oSegments is null)
+            return;
+
+        foreach (var oSegment in oSegments)
+        {
+            var oPoints = oSegment
+                .Select(points => points.ToPointF())
+                .ToArray();
+
+            manager.AddFreeHandAnnot(oColor, oPoints);
+        }
+    }
+}

EnvelopeGenerator.Application/Common/Extensions/JsonExtensions.cs

@@ -0,0 +1,18 @@
+using System.Text.Json;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class JsonExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="obj"></param>
+    /// <param name="options"></param>
+    /// <returns></returns>
+    public static string ToJson(this object obj, JsonSerializerOptions? options = null)
+        => JsonSerializer.Serialize(obj, options);
+}

EnvelopeGenerator.Application/Common/Extensions/LoggerExtensions.cs

@@ -1,7 +1,7 @@
 using Microsoft.Extensions.Logging;
 using System.Text;
 
-namespace EnvelopeGenerator.Extensions
+namespace EnvelopeGenerator.Application.Common.Extensions
 {
     public static class LoggerExtensions
     {

EnvelopeGenerator.Application/Common/Extensions/MappingExtensions.cs

@@ -0,0 +1,27 @@
+using EnvelopeGenerator.Application.Common.Dto.Messaging;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// Provides extension methods for common mapping and conversion operations.
+/// </summary>
+public static class MappingExtensions
+{
+    /// <summary>
+    /// Determines whether the response indicates a successful "OK" message status.
+    /// </summary>
+    /// <param name="gtxMessagingResponse">The response object to evaluate.</param>
+    /// <returns><see langword="true"/> if the response contains a "message-status" key with a value of "ok"  (case-insensitive);
+    /// otherwise, <see langword="false"/>.</returns>
+    public static bool Ok(this GtxMessagingResponse gtxMessagingResponse)
+        => gtxMessagingResponse.TryGetValue("message-status", out var status)
+        && status?.ToString()?.ToLower() == "ok";
+
+    /// <summary>
+    /// Converts the specified byte array to its equivalent string representation encoded in base-64.
+    /// </summary>
+    /// <param name="bytes">The byte array to encode.</param>
+    /// <returns>A base-64 encoded string representation of the input byte array.</returns>
+    public static string ToBase64String(this byte[] bytes)
+        => Convert.ToBase64String(bytes);
+}

EnvelopeGenerator.Application/Common/Extensions/MathematExtensions.cs

@@ -0,0 +1,40 @@
+using System.Drawing;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class MathematExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="points"></param>
+    /// <returns></returns>
+    public static PointF ToPointF(this List<float> points)
+    {
+        var pointsInch = points.Select(ToInches).ToList();
+        return new PointF(pointsInch[0], pointsInch[1]);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="value"></param>
+    /// <returns></returns>
+    public static double ToInches(this double value)
+    {
+        return value / 72.0;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="value"></param>
+    /// <returns></returns>
+    public static float ToInches(this float value)
+    {
+        return value / 72f;
+    }
+}

EnvelopeGenerator.Application/Common/Extensions/MemoryCacheExtensions.cs

@@ -1,11 +1,24 @@
-using Microsoft.Extensions.Caching.Memory;
+using EnvelopeGenerator.Application.Common.Extensions;
+using Microsoft.Extensions.Caching.Memory;
 
-namespace EnvelopeGenerator.Extensions;
+namespace EnvelopeGenerator.Application.Common.Extensions;
 
+/// <summary>
+/// 
+/// </summary>
 public static class MemoryCacheExtensions
 {
     private static readonly Guid BaseId = Guid.NewGuid();
 
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <typeparam name="TEnum"></typeparam>
+    /// <param name="memoryCache"></param>
+    /// <param name="key"></param>
+    /// <param name="ignores"></param>
+    /// <returns></returns>
+    /// <exception cref="InvalidOperationException"></exception>
     public static IDictionary<string, int> GetEnumAsDictionary<TEnum>(this IMemoryCache memoryCache, string key = "", params object[] ignores)
         where TEnum : Enum
         => memoryCache.GetOrCreate(BaseId + typeof(TEnum).FullName + key, _ =>

EnvelopeGenerator.Application/Common/Extensions/QueryExtensions.cs

@@ -0,0 +1,125 @@
+using DigitalData.Core.Exceptions;
+using EnvelopeGenerator.Application.Common.Extensions;
+using EnvelopeGenerator.Application.Common.Query;
+using EnvelopeGenerator.Domain.Entities;
+using EnvelopeGenerator.Domain.Interfaces;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class QueryExtensions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <typeparam name="TEntity"></typeparam>
+    /// <param name="root"></param>
+    /// <param name="query"></param>
+    /// <param name="notnull"></param>
+    /// <returns></returns>
+    /// <exception cref="BadRequestException"></exception>
+    public static IQueryable<TEntity> Where<TEntity>(this IQueryable<TEntity> root, EnvelopeQueryBase query, bool notnull = true)
+        where TEntity : IHasEnvelope
+    {
+        if (query.Id is not null)
+            root = root.Where(e => e.Envelope!.Id == query.Id);
+        else if (query.Uuid is not null)
+            root = root.Where(e => e.Envelope!.Uuid == query.Uuid);
+        else if (notnull)
+            throw new BadRequestException(
+                "Either Envelope Id or Envelope Uuid must be provided in the query."
+            );
+
+        return root;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="root"></param>
+    /// <param name="query"></param>
+    /// <param name="notnull"></param>
+    /// <returns></returns>
+    /// <exception cref="BadRequestException"></exception>
+    public static IQueryable<Envelope> Where(this IQueryable<Envelope> root, EnvelopeQueryBase query, bool notnull = true)
+    {
+        if (query.Id is not null)
+            root = root.Where(e => e.Id == query.Id);
+        else if (query.Uuid is not null)
+            root = root.Where(e => e.Uuid == query.Uuid);
+        else if (notnull)
+            throw new BadRequestException(
+                "Either Envelope Id or Envelope Uuid must be provided in the query."
+            );
+
+        return root;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <typeparam name="TEntity"></typeparam>
+    /// <param name="root"></param>
+    /// <param name="query"></param>
+    /// <param name="notnull"></param>
+    /// <returns></returns>
+    /// <exception cref="BadRequestException"></exception>
+    public static IQueryable<TEntity> Where<TEntity>(this IQueryable<TEntity> root, ReceiverQueryBase query, bool notnull = true)
+        where TEntity : IHasReceiver
+    {
+        if (query.Id is not null)
+            root = root.Where(e => e.Receiver!.Id == query.Id);
+        else if (query.EmailAddress is not null)
+            root = root.Where(e => e.Receiver!.EmailAddress == query.EmailAddress);
+        else if (query.Signature is not null)
+            root = root.Where(e => e.Receiver!.Signature == query.Signature);
+        else if (notnull)
+            throw new BadRequestException(
+                "Receiver must have at least one identifier (Id, EmailAddress, or Signature)."
+            );
+
+        return root;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="root"></param>
+    /// <param name="query"></param>
+    /// <param name="notnull"></param>
+    /// <returns></returns>
+    /// <exception cref="BadRequestException"></exception>
+    public static IQueryable<Receiver> Where(this IQueryable<Receiver> root, ReceiverQueryBase query, bool notnull = true)
+    {
+        if (query.Id is not null)
+            root = root.Where(e => e.Id == query.Id);
+        else if (query.EmailAddress is not null)
+            root = root.Where(e => e.EmailAddress == query.EmailAddress);
+        else if (query.Signature is not null)
+            root = root.Where(e => e.Signature == query.Signature);
+        else if (notnull)
+            throw new BadRequestException(
+                "Receiver must have at least one identifier (Id, EmailAddress, or Signature)."
+            );
+
+        return root;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <typeparam name="TEntity"></typeparam>
+    /// <typeparam name="TEnvelopeQuery"></typeparam>
+    /// <typeparam name="TReceiverQuery"></typeparam>
+    /// <param name="root"></param>
+    /// <param name="query"></param>
+    /// <param name="notnull"></param>
+    /// <returns></returns>
+    public static IQueryable<TEntity> Where<TEntity, TEnvelopeQuery, TReceiverQuery>(this IQueryable<TEntity> root, EnvelopeReceiverQueryBase<TEnvelopeQuery, TReceiverQuery> query, bool notnull = true)
+        where TEntity : IHasEnvelope, IHasReceiver
+        where TEnvelopeQuery : EnvelopeQueryBase, new()
+        where TReceiverQuery : ReceiverQueryBase, new() 
+        => root.Where(query.Envelope, notnull).Where(query.Receiver, notnull);
+}

EnvelopeGenerator.Application/Common/Extensions/StringExtension.cs

@@ -0,0 +1,30 @@
+using OtpNet;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// 
+/// </summary>
+public static class StringExtension
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="totp"></param>
+    /// <param name="secret"></param>
+    /// <returns></returns>
+    public static bool IsValidTotp(this string totp, string secret)
+    {
+        var secret_bytes = Base32Encoding.ToBytes(secret);
+        var secret_totp = new Totp(secret_bytes);
+        return secret_totp.VerifyTotp(totp, out _, VerificationWindow.RfcSpecifiedNetworkDelay);
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="seperator"></param>
+    /// <param name="values"></param>
+    /// <returns></returns>
+    public static string Join(this IEnumerable<string> values, string seperator) => string.Join(seperator, values);
+}

EnvelopeGenerator.Application/Common/Extensions/TaskExtensions.cs

@@ -0,0 +1,78 @@
+using DigitalData.Core.Exceptions;
+
+namespace EnvelopeGenerator.Application.Common.Extensions;
+
+/// <summary>
+/// Extension methods for tasks
+/// </summary>
+public static class TaskExtensions
+{
+    /// <summary>
+    /// Awaits the specified task and ensures that the result is not <c>null</c>.
+    /// If the result is <c>null</c>, the exception created by factory-method is thrown.
+    /// </summary>
+    /// <typeparam name="T">The type of the result.</typeparam>
+    /// <typeparam name="TException">The type of the exception.</typeparam>
+    /// <param name="task">The task to await.</param>
+    /// <param name="factory">Exception provider</param>
+    /// <returns>The awaited result if not <c>null</c>.</returns>
+    /// <exception>Thrown if the result is <c>null</c>.</exception>
+    public static async Task<T> ThrowIfNull<T, TException>(this Task<T?> task, Func<TException> factory) where TException : Exception
+    {
+        var result = await task;
+        return result ?? throw factory();
+    }
+
+    /// <summary>
+    /// Awaits the specified task and ensures that the result is not <c>empty</c>.
+    /// If the result contains no elements, the exception created by factory-method is thrown.
+    /// </summary>
+    /// <typeparam name="T">The element type of the collection.</typeparam>
+    /// <typeparam name="TException">The type of the exception.</typeparam>
+    /// <param name="task">The task to await.</param>
+    /// <param name="factory">Exception provider</param>
+    /// <returns>The awaited collection if it is not <c>null</c> or empty.</returns>
+    /// <exception cref="NotFoundException">Thrown if the result is <c>null</c> or empty.</exception>
+    public static async Task<IEnumerable<T>> ThrowIfEmpty<T, TException>(this Task<IEnumerable<T>> task, Func<TException> factory) where TException : Exception
+    {
+        var result = await task;
+        return result?.Any() ?? false ? result : throw factory();
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <typeparam name="T"></typeparam>
+    /// <typeparam name="I"></typeparam>
+    /// <param name="task"></param>
+    /// <param name="act"></param>
+    /// <returns></returns>
+    public static async Task<I> Then<T, I>(this Task<T> task, Func<T, I> act)
+    {
+        var res = await task;
+        return act(res);
+    }
+}
+
+/// <summary>
+/// 
+/// </summary>
+public static class Exceptions
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public static NotFoundException NotFound() => new();
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <returns></returns>
+    public static BadRequestException BadRequest() => new();
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <returns></returns>
+    public static ForbiddenException Forbidden() => new();
+}

EnvelopeGenerator.Application/Common/Extensions/XSSExtensions.cs

@@ -2,7 +2,7 @@
 using Microsoft.Extensions.Localization;
 using System.Text.Encodings.Web;
 
-namespace EnvelopeGenerator.Extensions
+namespace EnvelopeGenerator.Application.Common.Extensions
 {
     public static class XSSExtensions
     {

EnvelopeGenerator.Application/Common/Interfaces/Model/ITextStyle.cs

@@ -0,0 +1,27 @@
+using System.Diagnostics.CodeAnalysis;
+using System.Drawing;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Model;
+
+/// <summary>
+/// 
+/// </summary>
+public interface ITextStyle
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public string FontName { get; set; }
+
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public int FontSize { get; set; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    [SuppressMessage("Interoperability", "CA1416:Validate platform compatibility", Justification = "<Pending>")]
+    public FontStyle FontStyle { get; set; }
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IConfigRepository.cs

@@ -0,0 +1,17 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IConfigRepository : ICRUDRepository<Config, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <returns></returns>
+    Task<Config?> ReadFirstAsync();
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IDocumentReceiverElementRepository.cs

@@ -0,0 +1,11 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IDocumentReceiverElementRepository : ICRUDRepository<Signature, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IDocumentStatusRepository.cs

@@ -0,0 +1,12 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IDocumentStatusRepository : ICRUDRepository<DocumentStatus, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IEmailTemplateRepository.cs

@@ -0,0 +1,19 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IEmailTemplateRepository : ICRUDRepository<EmailTemplate, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="type"></param>
+    /// <returns></returns>
+    Task<EmailTemplate?> ReadByNameAsync(EmailTemplateType type);
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IEnvelopeDocumentRepository.cs

@@ -0,0 +1,12 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IEnvelopeDocumentRepository : ICRUDRepository<Document, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IEnvelopeHistoryRepository.cs

@@ -0,0 +1,32 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IEnvelopeHistoryRepository : ICRUDRepository<History, long>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <param name="status"></param>
+    /// <returns></returns>
+    Task<int> CountAsync(int? envelopeId = null, string? userReference = null, EnvelopeStatus? status = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <param name="status"></param>
+    /// <param name="withSender"></param>
+    /// <param name="withReceiver"></param>
+    /// <returns></returns>
+    Task<IEnumerable<History>> ReadAsync(int? envelopeId = null, string? userReference = null, EnvelopeStatus? status = null, bool withSender = false, bool withReceiver = false);
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IEnvelopeReceiverReadOnlyRepository.cs

@@ -0,0 +1,12 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IEnvelopeReceiverReadOnlyRepository : ICRUDRepository<EnvelopeReceiverReadOnly, long>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IEnvelopeReceiverRepository.cs

@@ -0,0 +1,98 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Application.Envelopes.Queries;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IEnvelopeReceiverRepository : ICRUDRepository<EnvelopeReceiver, (int Envelope, int Receiver)>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<IEnumerable<EnvelopeReceiver>> ReadByUuidAsync(string uuid, bool withEnvelope = true, bool withReceiver = false, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="signature"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<IEnumerable<EnvelopeReceiver>> ReadBySignatureAsync(string signature, bool withEnvelope = false, bool withReceiver = true, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="signature"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<EnvelopeReceiver?> ReadByUuidSignatureAsync(string uuid, string signature, bool withEnvelope = true, bool withReceiver = true, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="signature"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<string?> ReadAccessCodeAsync(string uuid, string signature, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="signature"></param>
+    /// <returns></returns>
+    Task<int> CountAsync(string uuid, string signature);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="receiverId"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<EnvelopeReceiver?> ReadByIdAsync(int envelopeId, int receiverId, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="receiverId"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<string?> ReadAccessCodeByIdAsync(int envelopeId, int receiverId, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="username"></param>
+    /// <param name="min_status"></param>
+    /// <param name="max_status"></param>
+    /// <param name="ignore_statuses"></param>
+    /// <returns></returns>
+    Task<IEnumerable<EnvelopeReceiver>> ReadByUsernameAsync(string username, EnvelopeStatus? min_status = null, EnvelopeStatus? max_status = null, params EnvelopeStatus[] ignore_statuses);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="email"></param>
+    /// <param name="id"></param>
+    /// <param name="signature"></param>
+    /// <returns></returns>
+    Task<EnvelopeReceiver?> ReadLastByReceiverAsync(string? email = null, int? id = null, string? signature = null);
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IEnvelopeRepository.cs

@@ -0,0 +1,43 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IEnvelopeRepository : ICRUDRepository<Envelope, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="documents"></param>
+    /// <param name="history"></param>
+    /// <param name="documentReceiverElement"></param>
+    /// <returns></returns>
+    Task<IEnumerable<Envelope>> ReadAllWithAsync(bool documents = false, bool history = false, bool documentReceiverElement = false);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="withDocuments"></param>
+    /// <param name="withHistory"></param>
+    /// <param name="withDocumentReceiverElement"></param>
+    /// <param name="withUser"></param>
+    /// <param name="withAll"></param>
+    /// <returns></returns>
+    Task<Envelope?> ReadByUuidAsync(string uuid, bool withDocuments = false, bool withHistory = false, bool withDocumentReceiverElement = false, bool withUser = false, bool withAll = false);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="userId"></param>
+    /// <param name="min_status"></param>
+    /// <param name="max_status"></param>
+    /// <param name="ignore_statuses"></param>
+    /// <returns></returns>
+    Task<IEnumerable<Envelope>> ReadByUserAsync(int userId, EnvelopeStatus? min_status = null, EnvelopeStatus? max_status = null, params EnvelopeStatus[] ignore_statuses);
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IEnvelopeTypeRepository.cs

@@ -0,0 +1,12 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IEnvelopeTypeRepository : ICRUDRepository<EnvelopeType, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Repositories/IReceiverRepository.cs

@@ -0,0 +1,19 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Repositories;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use IRepository")]
+public interface IReceiverRepository : ICRUDRepository<Receiver, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="emailAddress"></param>
+    /// <param name="signature"></param>
+    /// <returns></returns>
+    Task<Receiver?> ReadByAsync(string? emailAddress = null, string? signature = null);
+}

EnvelopeGenerator.Application/Common/Interfaces/SQLExecutor/IDocumentExecutor.cs

@@ -1,6 +1,6 @@
 using EnvelopeGenerator.Domain.Entities;
 
-namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+namespace EnvelopeGenerator.Application.Common.Interfaces.SQLExecutor;
 
 /// <summary>
 /// 
@@ -14,5 +14,5 @@ public interface IDocumentExecutor
     /// <param name="envelope_uuid"></param>
     /// <param name="cancellation"></param>
     /// <returns></returns>
-    Task<EnvelopeDocument> CreateDocumentAsync(string base64, string envelope_uuid, CancellationToken cancellation = default);
+    Task<Document> CreateDocumentAsync(string base64, string envelope_uuid, CancellationToken cancellation = default);
 }

EnvelopeGenerator.Application/Common/Interfaces/SQLExecutor/IEnvelopeExecutor.cs

@@ -1,7 +1,7 @@
 using Dapper;
 using EnvelopeGenerator.Domain.Entities;
 
-namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+namespace EnvelopeGenerator.Application.Common.Interfaces.SQLExecutor;
 
 /// <summary>
 /// 

EnvelopeGenerator.Application/Common/Interfaces/SQLExecutor/IEnvelopeReceiverExecutor.cs

@@ -1,6 +1,6 @@
 using EnvelopeGenerator.Domain.Entities;
 
-namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+namespace EnvelopeGenerator.Application.Common.Interfaces.SQLExecutor;
 
 /// <summary>
 /// 

EnvelopeGenerator.Application/Common/Interfaces/SQLExecutor/IQuery.cs

@@ -1,4 +1,4 @@
-namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+namespace EnvelopeGenerator.Application.Common.Interfaces.SQLExecutor;
 
 /// <summary>
 /// Provides methods for executing common queries on a given entity type.

EnvelopeGenerator.Application/Common/Interfaces/SQLExecutor/ISQL.cs

@@ -1,4 +1,4 @@
-namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+namespace EnvelopeGenerator.Application.Common.Interfaces.SQLExecutor;
 
 /// <summary>
 /// Represents a raw SQL query contract.

EnvelopeGenerator.Application/Common/Interfaces/SQLExecutor/ISQLExecutor.cs

@@ -1,4 +1,4 @@
-namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+namespace EnvelopeGenerator.Application.Common.Interfaces.SQLExecutor;
 
 /// <summary>
 /// Defines methods for executing raw SQL queries or custom SQL query classes and returning query executors for further operations.

EnvelopeGenerator.Application/Common/Interfaces/SQLExecutor/ISQLExecutorBaseEntity.cs

@@ -1,6 +1,6 @@
 using Dapper;
 
-namespace EnvelopeGenerator.Application.Contracts.SQLExecutor;
+namespace EnvelopeGenerator.Application.Common.Interfaces.SQLExecutor;
 
 /// <summary>
 /// 

EnvelopeGenerator.Application/Common/Interfaces/Services/IAuthenticator.cs

@@ -0,0 +1,63 @@
+using OtpNet;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+public interface IAuthenticator
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="length"></param>
+    /// <returns></returns>
+    string GenerateCode(int length);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="length"></param>
+    /// <returns></returns>
+    string GenerateTotpSecretKey(int? length = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="userEmail"></param>
+    /// <param name="secretKey"></param>
+    /// <param name="issuer"></param>
+    /// <param name="totpUrlFormat"></param>
+    /// <param name="pixelsPerModule"></param>
+    /// <returns></returns>
+    byte[] GenerateTotpQrCode(string userEmail, string secretKey, string? issuer = null, string? totpUrlFormat = null, int? pixelsPerModule = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="userEmail"></param>
+    /// <param name="length"></param>
+    /// <param name="issuer"></param>
+    /// <param name="totpUrlFormat"></param>
+    /// <param name="pixelsPerModule"></param>
+    /// <returns></returns>
+    byte[] GenerateTotpQrCode(string userEmail, int? length = null, string? issuer = null, string? totpUrlFormat = null, int? pixelsPerModule = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="secretKey"></param>
+    /// <param name="step"></param>
+    /// <returns></returns>
+    string GenerateTotp(string secretKey, int step = 30);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="totpCode"></param>
+    /// <param name="secretKey"></param>
+    /// <param name="step"></param>
+    /// <param name="window"></param>
+    /// <returns></returns>
+    bool VerifyTotp(string totpCode, string secretKey, int step = 30, VerificationWindow? window = null);
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IConfigService.cs

@@ -0,0 +1,31 @@
+using DigitalData.Core.Abstraction.Application;
+using DigitalData.Core.Abstraction.Application.DTO;
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IConfigService : IReadService<ConfigDto, Config, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <returns></returns>
+    Task<DataResult<ConfigDto>> ReadFirstAsync();
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <returns></returns>
+    Task<ConfigDto> ReadDefaultAsync();
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <returns></returns>
+    Task<string> ReadDefaultSignatureHost();
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IDocumentReceiverElementService.cs

@@ -0,0 +1,13 @@
+using DigitalData.Core.Abstraction.Application;
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IDocumentReceiverElementService : IBasicCRUDService<SignatureDto, Signature, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IDocumentStatusService.cs

@@ -0,0 +1,12 @@
+using DigitalData.Core.Abstraction.Application;
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Domain.Entities;
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IDocumentStatusService : IBasicCRUDService<DocumentStatusDto, DocumentStatus, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEmailTemplateService.cs

@@ -0,0 +1,21 @@
+using DigitalData.Core.Abstraction.Application;
+using DigitalData.Core.Abstraction.Application.DTO;
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEmailTemplateService : IBasicCRUDService<EmailTemplateDto, EmailTemplate, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="type"></param>
+    /// <returns></returns>
+    Task<DataResult<EmailTemplateDto>> ReadByNameAsync(EmailTemplateType type);
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeDocumentService.cs

@@ -0,0 +1,13 @@
+using DigitalData.Core.Abstraction.Application;
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEnvelopeDocumentService : IBasicCRUDService<DocumentDto, Document, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeHistoryService.cs

@@ -0,0 +1,85 @@
+using DigitalData.Core.Abstraction.Application;
+using DigitalData.Core.Abstraction.Application.DTO;
+using EnvelopeGenerator.Application.Common.Dto.History;
+using EnvelopeGenerator.Application.Common.Dto.Receiver;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEnvelopeHistoryService : ICRUDService<HistoryCreateDto, HistoryDto, History, long>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <param name="status"></param>
+    /// <returns></returns>
+    Task<int> CountAsync(int? envelopeId = null, string? userReference = null, EnvelopeStatus? status = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <returns></returns>
+    Task<bool> AccessCodeAlreadyRequested(int envelopeId, string userReference);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <returns></returns>
+    Task<bool> IsSigned(int envelopeId, string userReference);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <returns></returns>
+    Task<bool> IsRejected(int envelopeId, string? userReference = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <param name="referenceType"></param>
+    /// <param name="status"></param>
+    /// <param name="withSender"></param>
+    /// <param name="withReceiver"></param>
+    /// <returns></returns>
+    Task<IEnumerable<HistoryDto>> ReadAsync(int? envelopeId = null, string? userReference = null, ReferenceType? referenceType = null, EnvelopeStatus? status = null, bool withSender = false, bool withReceiver = false);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <returns></returns>
+    Task<IEnumerable<HistoryDto>> ReadRejectedAsync(int envelopeId, string? userReference = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <returns></returns>
+    Task<IEnumerable<ReceiverDto>> ReadRejectingReceivers(int envelopeId);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="userReference"></param>
+    /// <param name="status"></param>
+    /// <param name="comment"></param>
+    /// <returns></returns>
+    Task<DataResult<long>> RecordAsync(int envelopeId, string userReference, EnvelopeStatus status, string? comment = null);
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeMailService.cs

@@ -0,0 +1,38 @@
+using DigitalData.Core.Abstraction.Application.DTO;
+using DigitalData.EmailProfilerDispatcher.Abstraction.Contracts;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly;
+using EnvelopeGenerator.Domain.Constants;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEnvelopeMailService : IEmailOutService
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeReceiverDto"></param>
+    /// <param name="tempType"></param>
+    /// <param name="optionalPlaceholders"></param>
+    /// <returns></returns>
+    Task<DataResult<int>> SendAsync(EnvelopeReceiverDto envelopeReceiverDto, EmailTemplateType tempType, Dictionary<string, object>? optionalPlaceholders = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="dto"></param>
+    /// <param name="optionalPlaceholders"></param>
+    /// <returns></returns>
+    Task<DataResult<int>> SendAsync(EnvelopeReceiverReadOnlyDto dto, Dictionary<string, object>? optionalPlaceholders = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeReceiverDto"></param>
+    /// <returns></returns>
+    Task<DataResult<int>> SendAccessCodeAsync(EnvelopeReceiverDto envelopeReceiverDto);
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeReceiverReadOnlyService.cs

@@ -0,0 +1,13 @@
+using DigitalData.Core.Abstraction.Application;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEnvelopeReceiverReadOnlyService : ICRUDService<EnvelopeReceiverReadOnlyCreateDto, EnvelopeReceiverReadOnlyDto, EnvelopeReceiverReadOnly, long>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeReceiverService.cs

@@ -0,0 +1,151 @@
+using CommandDotNet;
+using DigitalData.Core.Abstraction.Application;
+using DigitalData.Core.Abstraction.Application.DTO;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+using EnvelopeGenerator.Application.Common.Dto.Messaging;
+using EnvelopeGenerator.Application.Envelopes;
+using EnvelopeGenerator.Application.Envelopes.Queries;
+using EnvelopeGenerator.Application.Receivers.Queries;
+using EnvelopeGenerator.Domain;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEnvelopeReceiverService : IBasicCRUDService<EnvelopeReceiverDto, EnvelopeReceiver, (int Envelope, int Receiver)>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+
+    Task<DataResult<IEnumerable<EnvelopeReceiverDto>>> ReadByUuidAsync(string uuid, bool withEnvelope = true, bool withReceiver = false, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <returns></returns>
+    Task<DataResult<IEnumerable<string?>>> ReadAccessCodeByUuidAsync(string uuid, bool withEnvelope = false, bool withReceiver = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="signature"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<DataResult<IEnumerable<EnvelopeReceiverDto>>> ReadBySignatureAsync(string signature, bool withEnvelope = false, bool withReceiver = true, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="signature"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<DataResult<EnvelopeReceiverDto>> ReadByUuidSignatureAsync(string uuid, string signature, bool withEnvelope = true, bool withReceiver = true, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="signature"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<DataResult<EnvelopeReceiverSecretDto>> ReadWithSecretByUuidSignatureAsync(string uuid, string signature, bool withEnvelope = true, bool withReceiver = true, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeReceiverId"></param>
+    /// <param name="withEnvelope"></param>
+    /// <param name="withReceiver"></param>
+    /// <param name="readOnly"></param>
+    /// <returns></returns>
+    Task<DataResult<EnvelopeReceiverDto>> ReadByEnvelopeReceiverIdAsync(string envelopeReceiverId, bool withEnvelope = true, bool withReceiver = true, bool readOnly = true);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeId"></param>
+    /// <param name="receiverId"></param>
+    /// <returns></returns>
+    Task<DataResult<string>> ReadAccessCodeByIdAsync(int envelopeId, int receiverId);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="signature"></param>
+    /// <param name="accessCode"></param>
+    /// <returns></returns>
+    Task<DataResult<bool>> VerifyAccessCodeAsync(string uuid, string signature, string accessCode);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeReceiverId"></param>
+    /// <param name="accessCode"></param>
+    /// <returns></returns>
+    [Command("verify-access-code-async-by-id")]
+    Task<DataResult<bool>> VerifyAccessCodeAsync(string envelopeReceiverId, string accessCode);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeReceiverId"></param>
+    /// <returns></returns>
+    Task<DataResult<bool>> IsExisting(string envelopeReceiverId);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="username"></param>
+    /// <param name="min_status"></param>
+    /// <param name="max_status"></param>
+    /// <param name="envelopeQuery"></param>
+    /// <param name="receiverQuery"></param>
+    /// <param name="ignore_statuses"></param>
+    /// <returns></returns>
+    Task<DataResult<IEnumerable<EnvelopeReceiverDto>>> ReadByUsernameAsync(string username, EnvelopeStatus? min_status = null, EnvelopeStatus? max_status = null, ReadEnvelopeQuery? envelopeQuery = null, ReadReceiverQuery? receiverQuery = null, params EnvelopeStatus[] ignore_statuses);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="mail"></param>
+    /// <param name="id"></param>
+    /// <param name="signature"></param>
+    /// <returns></returns>
+    Task<DataResult<string>> ReadLastUsedReceiverNameByMailAsync(string? mail = null, int? id = null, string? signature = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="envelopeReceiverId"></param>
+    /// <param name="message"></param>
+    /// <returns></returns>
+    Task<DataResult<SmsResponse>> SendSmsAsync(string envelopeReceiverId, string message);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <returns></returns>
+    Task<DataResult<IEnumerable<EnvelopeReceiverSecretDto>>> ReadWithSecretByUuidAsync(string uuid);
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeService.cs

@@ -0,0 +1,45 @@
+using DigitalData.Core.Abstraction.Application;
+using DigitalData.Core.Abstraction.Application.DTO;
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEnvelopeService : IBasicCRUDService<EnvelopeDto, Envelope, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="documents"></param>
+    /// <param name="history"></param>
+    /// <param name="documentReceiverElement"></param>
+    /// <returns></returns>
+    Task<DataResult<IEnumerable<EnvelopeDto>>> ReadAllWithAsync(bool documents = false, bool history = false, bool documentReceiverElement = false);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="uuid"></param>
+    /// <param name="withDocuments"></param>
+    /// <param name="withHistory"></param>
+    /// <param name="withDocumentReceiverElement"></param>
+    /// <param name="withUser"></param>
+    /// <param name="withAll"></param>
+    /// <returns></returns>
+    Task<DataResult<EnvelopeDto>> ReadByUuidAsync(string uuid, bool withDocuments = false, bool withHistory = false, bool withDocumentReceiverElement = false, bool withUser = false, bool withAll = false);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="userId"></param>
+    /// <param name="min_status"></param>
+    /// <param name="max_status"></param>
+    /// <param name="ignore_statuses"></param>
+    /// <returns></returns>
+    Task<DataResult<IEnumerable<EnvelopeDto>>> ReadByUserAsync(int userId, EnvelopeStatus? min_status = null, EnvelopeStatus? max_status = null, params EnvelopeStatus[] ignore_statuses);
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeSmsHandler.cs

@@ -1,8 +1,11 @@
-using EnvelopeGenerator.Application.DTOs.EnvelopeReceiver;
-using EnvelopeGenerator.Application.DTOs.Messaging;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+using EnvelopeGenerator.Application.Common.Dto.Messaging;
 
-namespace EnvelopeGenerator.Application.Contracts.Services;
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
 
+/// <summary>
+/// 
+/// </summary>
 public interface IEnvelopeSmsHandler
 {
     /// <summary>
@@ -13,5 +16,11 @@ public interface IEnvelopeSmsHandler
     /// <returns></returns>
     Task<(SmsResponse? SmsResponse, DateTime Expiration)> SendTotpAsync(EnvelopeReceiverSecretDto er_secret, CancellationToken cToken = default);
 
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="totpCode"></param>
+    /// <param name="secretKey"></param>
+    /// <returns></returns>
     bool VerifyTotp(string totpCode, string secretKey);
 }

EnvelopeGenerator.Application/Common/Interfaces/Services/IEnvelopeTypeService.cs

@@ -0,0 +1,13 @@
+using DigitalData.Core.Abstraction.Application;
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IEnvelopeTypeService : IBasicCRUDService<EnvelopeTypeDto, EnvelopeType, int>
+{
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/IReceiverService.cs

@@ -0,0 +1,30 @@
+using DigitalData.Core.Abstraction.Application;
+using DigitalData.Core.Abstraction.Application.DTO;
+using EnvelopeGenerator.Application.Common.Dto.Receiver;
+using EnvelopeGenerator.Application.Receivers.Commands;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+/// <summary>
+/// 
+/// </summary>
+[Obsolete("Use MediatR")]
+public interface IReceiverService : ICRUDService<CreateReceiverCommand, ReceiverDto, Receiver, int>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="emailAddress"></param>
+    /// <param name="signature"></param>
+    /// <returns></returns>
+    Task<DataResult<ReceiverDto>> ReadByAsync(string? emailAddress = null, string? signature = null);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="emailAddress"></param>
+    /// <param name="signature"></param>
+    /// <returns></returns>
+    Task<Result> DeleteByAsync(string? emailAddress = null, string? signature = null);
+}

EnvelopeGenerator.Application/Common/Interfaces/Services/ISmsSender.cs

@@ -0,0 +1,23 @@
+using EnvelopeGenerator.Application.Common.Dto.Messaging;
+
+namespace EnvelopeGenerator.Application.Common.Interfaces.Services;
+
+//TODO: move to DigitalData.Core
+/// <summary>
+/// 
+/// </summary>
+public interface ISmsSender
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    string ServiceProvider { get; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="recipient"></param>
+    /// <param name="message"></param>
+    /// <returns></returns>
+    Task<SmsResponse> SendSmsAsync(string recipient, string message);
+}

EnvelopeGenerator.Application/Common/Notifications/DocSigned/DocSignedNotification.cs

@@ -0,0 +1,88 @@
+using EnvelopeGenerator.Application.Common.Dto;
+using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver;
+using EnvelopeGenerator.Application.Common.Extensions;
+using EnvelopeGenerator.Application.Common.Notifications.RemoveSignature;
+using EnvelopeGenerator.Domain.Constants;
+using MediatR;
+using System.Dynamic;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.DocSigned;
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="Instant"></param>
+/// <param name="Structured"></param>
+public record PsPdfKitAnnotation(ExpandoObject Instant, IEnumerable<AnnotationCreateDto> Structured);
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="Original"></param>
+public record DocSignedNotification(EnvelopeReceiverDto Original) : EnvelopeReceiverDto(Original), INotification, ISendMailNotification
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public PsPdfKitAnnotation PsPdfKitAnnotation { get; init; } = null!;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public EmailTemplateType TemplateType => EmailTemplateType.DocumentSigned;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string EmailAddress => Receiver?.EmailAddress
+        ?? throw new InvalidOperationException($"Receiver is null." +
+            $"DocSignedNotification:\n{this.ToJson(Format.Json.ForDiagnostics)}");
+}
+
+/// <summary>
+/// 
+/// </summary>
+public static class DocSignedNotificationExtensions
+{
+    /// <summary>
+    /// Converts an <see cref="EnvelopeReceiverDto"/> to a <see cref="DocSignedNotification"/>.
+    /// </summary>
+    /// <param name="dto">The DTO to convert.</param>
+    /// <param name="psPdfKitAnnotation"></param>
+    /// <returns>A new <see cref="DocSignedNotification"/> instance.</returns>
+    public static DocSignedNotification ToDocSignedNotification(this EnvelopeReceiverDto dto, PsPdfKitAnnotation psPdfKitAnnotation)
+        => new(dto) { PsPdfKitAnnotation = psPdfKitAnnotation };
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="dtoTask"></param>
+    /// <param name="psPdfKitAnnotation"></param>
+    /// <returns></returns>
+    public static async Task<DocSignedNotification?> ToDocSignedNotification(this Task<EnvelopeReceiverDto?> dtoTask, PsPdfKitAnnotation psPdfKitAnnotation)
+        => await dtoTask is EnvelopeReceiverDto dto ? new(dto) { PsPdfKitAnnotation = psPdfKitAnnotation } : null;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="publisher"></param>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public static async Task PublishSafely(this IPublisher publisher, DocSignedNotification notification, CancellationToken cancel = default)
+    {
+        try
+        {
+            await publisher.Publish(notification, cancel);
+        }
+        catch (Exception)
+        {
+            await publisher.Publish(new RemoveSignatureNotification()
+            {
+                EnvelopeId = notification.EnvelopeId,
+                ReceiverId = notification.ReceiverId
+            }, cancel);
+            throw;
+        }
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/DocSigned/Handlers/AnnotationHandler.cs

@@ -0,0 +1,34 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+using MediatR;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.DocSigned.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class AnnotationHandler : INotificationHandler<DocSignedNotification>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    private readonly IRepository<ElementAnnotation> _repo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="repository"></param>
+    public AnnotationHandler(IRepository<ElementAnnotation> repository)
+    {
+        _repo = repository;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public Task Handle(DocSignedNotification notification, CancellationToken cancel)
+        => _repo.CreateAsync(notification.PsPdfKitAnnotation.Structured, cancel);
+}

EnvelopeGenerator.Application/Common/Notifications/DocSigned/Handlers/DocStatusHandler.cs

@@ -0,0 +1,39 @@
+using EnvelopeGenerator.Application.DocStatus.Commands;
+using EnvelopeGenerator.Domain.Constants;
+using MediatR;
+using System.Text.Json;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.DocSigned.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class DocStatusHandler : INotificationHandler<DocSignedNotification>
+{
+    private readonly ISender _sender;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="sender"></param>
+    public DocStatusHandler(ISender sender)
+    {
+        _sender = sender;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public async Task Handle(DocSignedNotification notification, CancellationToken cancel)
+    {
+        await _sender.Send(new SaveDocStatusCommand()
+        {
+            Envelope = new() { Id = notification.EnvelopeId },
+            Receiver = new() { Id = notification.ReceiverId},
+            Value = JsonSerializer.Serialize(notification.PsPdfKitAnnotation.Instant, Format.Json.ForAnnotations)
+        }, cancel);
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/DocSigned/Handlers/HistoryHandler.cs

@@ -0,0 +1,42 @@
+using EnvelopeGenerator.Application.Common.Extensions;
+using EnvelopeGenerator.Application.Histories.Commands;
+using EnvelopeGenerator.Domain.Constants;
+using MediatR;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.DocSigned.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class HistoryHandler : INotificationHandler<DocSignedNotification>
+{
+    private readonly ISender _sender;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="sender"></param>
+    public HistoryHandler(ISender sender)
+    {
+        _sender = sender;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public async Task Handle(DocSignedNotification notification, CancellationToken cancel)
+    {
+        if (notification.Receiver is null)
+            throw new InvalidOperationException($"Receiver information is missing in the notification. DocSignedNotification:\n {notification.ToJson(Format.Json.ForDiagnostics)}");
+
+        await _sender.Send(new CreateHistoryCommand()
+        {
+            EnvelopeId = notification.EnvelopeId,
+            UserReference = notification.Receiver.EmailAddress,
+            Status = EnvelopeStatus.DocumentSigned,
+        }, cancel);
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/DocSigned/Handlers/SendSignedMailHandler.cs

@@ -0,0 +1,50 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using DigitalData.EmailProfilerDispatcher.Abstraction.Entities;
+using EnvelopeGenerator.Application.Common.Configurations;
+using EnvelopeGenerator.Domain.Entities;
+using Microsoft.Extensions.Options;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.DocSigned.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class SendSignedMailHandler : SendMailHandler<DocSignedNotification>
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="tempRepo"></param>
+    /// <param name="emailOutRepo"></param>
+    /// <param name="mailParamsOptions"></param>
+    /// <param name="dispatcherParamsOptions"></param>
+    public SendSignedMailHandler(IRepository<EmailTemplate> tempRepo, IRepository<EmailOut> emailOutRepo, IOptions<MailParams> mailParamsOptions, IOptions<DispatcherParams> dispatcherParamsOptions) : base(tempRepo, emailOutRepo, mailParamsOptions, dispatcherParamsOptions)
+    {
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="emailOut"></param>
+    protected override void ConfigureEmailOut(DocSignedNotification notification, EmailOut emailOut)
+    {
+        emailOut.ReferenceString = notification.EmailAddress;
+        emailOut.ReferenceId = notification.ReceiverId;
+    }
+
+    /// <summary>
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <returns></returns>
+    protected override Dictionary<string, string> CreatePlaceHolders(DocSignedNotification notification)
+    {
+        var placeHolders = new Dictionary<string, string>()
+        {
+            { "[NAME_RECEIVER]", notification.Name ?? string.Empty },
+            { "[DOCUMENT_TITLE]", notification.Envelope?.Title ?? string.Empty },
+        };
+
+        return placeHolders;
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/RemoveSignature/Handlers/RemoveAnnotationHandler.cs

@@ -0,0 +1,53 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+using MediatR;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.RemoveSignature.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class RemoveAnnotationHandler : INotificationHandler<RemoveSignatureNotification>
+{
+    private readonly IRepository<ElementAnnotation> _repo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="repository"></param>
+    public RemoveAnnotationHandler(IRepository<ElementAnnotation> repository)
+    {
+        _repo = repository;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public Task Handle(RemoveSignatureNotification notification, CancellationToken cancel)
+    {
+        notification.ThrowIfHasNoFilter();
+        return _repo.DeleteAsync(annots =>
+        {
+            // envelope ID filter
+            if (notification.EnvelopeId is int envelopeId)
+                annots = annots.Where(annot => annot.Element!.Document.EnvelopeId == envelopeId);
+
+            // envelope UUID filter
+            if (notification.EnvelopeUuid is string envelopeUuid)
+                annots = annots.Where(annot => annot.Element!.Document.Envelope!.Uuid == envelopeUuid);
+
+            // receiver ID
+            if (notification.ReceiverId is int receiverId)
+                annots = annots.Where(annot => annot.Element!.ReceiverId == receiverId);
+
+            // receiver signature
+            if (notification.ReceiverSignature is string receiverSignature)
+                annots = annots.Where(annot => annot.Element!.Receiver!.Signature == receiverSignature);
+
+            return annots;
+        }, cancel);
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/RemoveSignature/Handlers/RemoveDocResult.cs

@@ -0,0 +1,47 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Domain.Entities;
+using MediatR;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.RemoveSignature.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class RemoveDocResult : INotificationHandler<RemoveSignatureNotification>
+{
+    private readonly IRepository<Envelope> _repo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="repository"></param>
+    public RemoveDocResult(IRepository<Envelope> repository)
+    {
+        _repo = repository;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public Task Handle(RemoveSignatureNotification notification, CancellationToken cancel)
+    {
+        if(notification.EnvelopeId is null && notification.EnvelopeUuid is null)
+            return Task.CompletedTask;
+
+        return _repo.UpdateAsync(
+            envelope => envelope.DocResult = null,
+            query => {
+                if (notification.EnvelopeId is int envelopeId)
+                    query = query.Where(envelope => envelope.Id == envelopeId);
+
+                if (notification.EnvelopeUuid is string uuid)
+                    query = query.Where(envelope => envelope.Uuid == uuid);
+
+                return query;
+            }, cancel);
+
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/RemoveSignature/Handlers/RemoveDocStatusHandler.cs

@@ -0,0 +1,53 @@
+using AngleSharp.Html;
+using DigitalData.Core.Abstraction.Application.Repository;
+using MediatR;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.RemoveSignature.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class RemoveDocStatusHandler : INotificationHandler<RemoveSignatureNotification>
+{
+    private readonly IRepository<Domain.Entities.DocumentStatus> _repo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="repository"></param>
+    public RemoveDocStatusHandler(IRepository<Domain.Entities.DocumentStatus> repository)
+    {
+        _repo = repository;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public Task Handle(RemoveSignatureNotification notification, CancellationToken cancel)
+    {
+        notification.ThrowIfHasNoFilter();
+        return _repo.DeleteAsync(statuses =>
+        {
+            // envelope ID filter
+            if (notification.EnvelopeId is int envelopeId)
+                statuses = statuses.Where(status => status.EnvelopeId == envelopeId);
+
+            // envelope UUID filter
+            if (notification.EnvelopeUuid is string envelopeUuid)
+                statuses = statuses.Where(status => status.Envelope!.Uuid == envelopeUuid);
+
+            // receiver Id filter
+            if (notification.ReceiverId is int receiverId)
+                statuses = statuses.Where(status => status.ReceiverId == receiverId);
+
+            // receiver signature filter
+            if (notification.ReceiverSignature is string receiverSignature)
+                statuses = statuses.Where(status => status.Receiver!.Signature == receiverSignature);
+
+            return statuses;
+        }, cancel);
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/RemoveSignature/Handlers/RemoveHistoryHandler.cs

@@ -0,0 +1,56 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using EnvelopeGenerator.Application.Common.Extensions;
+using EnvelopeGenerator.Domain.Constants;
+using MediatR;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.RemoveSignature.Handlers;
+
+/// <summary>
+/// 
+/// </summary>
+public class RemoveHistoryHandler : INotificationHandler<RemoveSignatureNotification>
+{
+    private readonly IRepository<Domain.Entities.History> _repo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="repository"></param>
+    public RemoveHistoryHandler(IRepository<Domain.Entities.History> repository)
+    {
+        _repo = repository;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    public Task Handle(RemoveSignatureNotification notification, CancellationToken cancel)
+    {
+        notification.ThrowIfHasNoFilter();
+        return _repo.DeleteAsync(hists =>
+        {
+            hists = hists.Where(hist => hist.Status == EnvelopeStatus.DocumentSigned);
+
+            // envelope ID filter
+            if (notification.EnvelopeId is int envelopeId)
+                hists = hists.Where(hist => hist.EnvelopeId == envelopeId);
+
+            // envelope UUID filter
+            if (notification.EnvelopeUuid is string envelopeUuid)
+                hists = hists.Where(hist => hist.Envelope!.Uuid == envelopeUuid);
+
+            // receiver ID filter
+            if (notification.ReceiverId is int receiverId)
+                hists = hists.Where(hist => hist.Receiver!.Id == receiverId);
+
+            // receiver signature filter
+            if (notification.ReceiverSignature is string receiverSignature)
+                hists = hists.Where(hist => hist.Receiver!.Signature == receiverSignature);
+
+            return hists;
+        }, cancel);
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/RemoveSignature/RemoveSignatureNotification.cs

@@ -0,0 +1,37 @@
+using MediatR;
+
+namespace EnvelopeGenerator.Application.Common.Notifications.RemoveSignature;
+
+/// <summary>
+/// 
+/// </summary>
+/// <param name="EnvelopeId"></param>
+/// <param name="ReceiverId"></param>
+/// <param name="EnvelopeUuid"></param>
+/// <param name="ReceiverSignature"></param>
+public record RemoveSignatureNotification(
+    int? EnvelopeId = null,
+    int? ReceiverId = null,
+    string? EnvelopeUuid = null,
+    string? ReceiverSignature = null
+    ) : INotification
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public bool HasFilter => 
+        EnvelopeId is not null 
+        || ReceiverId is not null 
+        || EnvelopeUuid is not null 
+        || ReceiverSignature is not null;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <exception cref="InvalidOperationException"></exception>
+    public void ThrowIfHasNoFilter()
+    {
+        if (!HasFilter)
+            throw new InvalidOperationException("At least one filter parameter must be provided.");
+    }
+}

EnvelopeGenerator.Application/Common/Notifications/SendMailHandler.cs

@@ -0,0 +1,135 @@
+using DigitalData.Core.Abstraction.Application.Repository;
+using DigitalData.EmailProfilerDispatcher.Abstraction.Entities;
+using EnvelopeGenerator.Application.Common.Configurations;
+using EnvelopeGenerator.Application.Common.Extensions;
+using EnvelopeGenerator.Domain.Constants;
+using EnvelopeGenerator.Domain.Entities;
+using MediatR;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Options;
+using Newtonsoft.Json;
+
+namespace EnvelopeGenerator.Application.Common.Notifications;
+
+/// <summary>
+/// 
+/// </summary>
+public interface ISendMailNotification : INotification
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public EmailTemplateType TemplateType { get; }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public string EmailAddress { get; }
+}
+
+/// <summary>
+/// 
+/// </summary>
+public abstract class SendMailHandler<TNotification> : INotificationHandler<TNotification>
+    where TNotification : ISendMailNotification
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    protected readonly IRepository<EmailTemplate> TempRepo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    protected readonly IRepository<EmailOut> EmailOutRepo;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    protected abstract Dictionary<string, string> CreatePlaceHolders(TNotification notification);
+
+    /// <summary>
+    ///{ "[MESSAGE]", notification.Message },<br/>
+    ///{ "[DOCUMENT_ACCESS_CODE]", notification.ReceiverAccessCode },<br/>
+    ///{ "[REASON]", pReason }<br/>
+    ///{ "[NAME_SENDER]", notification.Envelope.User?.FullName},<br/>
+    ///{ "[NAME_PORTAL]", DispatcherParams. },<br/>
+    ///{ "[SIGNATURE_TYPE]", "signieren" },<br/>
+    ///{ "[LINK_TO_DOCUMENT]", notification.SignatureLink },<br/>
+    ///{ "[LINK_TO_DOCUMENT_TEXT]", $"{notification.SignatureLink.Truncate(40)}.." },
+    /// </summary>
+    protected readonly MailParams MailParams;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    protected readonly DispatcherParams DispatcherParams;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="emailOut"></param>
+    protected abstract void ConfigureEmailOut(TNotification notification, EmailOut emailOut);
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="tempRepo"></param>
+    /// <param name="emailOutRepo"></param>
+    /// <param name="mailParamsOptions"></param>
+    /// <param name="dispatcherParamsOptions"></param>
+    protected SendMailHandler(IRepository<EmailTemplate> tempRepo, IRepository<EmailOut> emailOutRepo, IOptions<MailParams> mailParamsOptions, IOptions<DispatcherParams> dispatcherParamsOptions)
+    {
+        TempRepo = tempRepo;
+        EmailOutRepo = emailOutRepo;
+        MailParams = mailParamsOptions.Value;
+        DispatcherParams = dispatcherParamsOptions.Value;
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="notification"></param>
+    /// <param name="cancel"></param>
+    /// <returns></returns>
+    /// <exception cref="NotImplementedException"></exception>
+    public virtual async Task Handle(TNotification notification, CancellationToken cancel)
+    {
+        var placeHolders = CreatePlaceHolders(notification);
+
+        var temp = await TempRepo
+            .Where(x => x.Name == notification.TemplateType.ToString())
+            .SingleOrDefaultAsync(cancel)
+                ?? throw new InvalidOperationException($"Receiver information is missing in the notification." +
+                $"{typeof(TNotification)}:\n {notification.ToJson(Format.Json.ForDiagnostics)}");
+
+        temp.Subject = ReplacePlaceHolders(temp.Subject, placeHolders, MailParams.Placeholders);
+
+        temp.Body = ReplacePlaceHolders(temp.Body, placeHolders, MailParams.Placeholders);
+
+        var emailOut = new EmailOut
+        {
+            EmailAddress = notification.EmailAddress,
+            EmailBody = temp.Body,
+            EmailSubj = temp.Subject,
+            AddedWhen = DateTime.UtcNow,
+            AddedWho = DispatcherParams.AddedWho,
+            SendingProfile = DispatcherParams.SendingProfile,
+            ReminderTypeId = DispatcherParams.ReminderTypeId,
+            EmailAttmt1 = DispatcherParams.EmailAttmt1,
+            WfId = (int)EnvelopeStatus.MessageConfirmationSent,
+            
+        };
+        ConfigureEmailOut(notification, emailOut);
+        await EmailOutRepo.CreateAsync(emailOut, cancel);
+    }
+
+    private static string ReplacePlaceHolders(string text, params Dictionary<string, string>[] placeHoldersList)
+    {
+        foreach (var placeHolders in placeHoldersList)
+            foreach (var ph in placeHolders)
+                text = text.Replace(ph.Key, ph.Value);
+        return text;
+    }
+}

EnvelopeGenerator.Application/Common/Query/EnvelopeQueryBase.cs

@@ -0,0 +1,17 @@
+namespace EnvelopeGenerator.Application.Common.Query;
+
+/// <summary>
+/// Repräsentiert eine Abfrage für Umschläge.
+/// </summary>
+public record EnvelopeQueryBase
+{
+    /// <summary>
+    /// Die eindeutige Kennung des Umschlags.
+    /// </summary>
+    public virtual int? Id { get; set; }
+
+    /// <summary>
+    /// Die universell eindeutige Kennung des Umschlags.
+    /// </summary>
+    public virtual string? Uuid { get; set; }
+}

EnvelopeGenerator.Application/Common/Query/EnvelopeReceiverQueryBase.cs

@@ -0,0 +1,62 @@
+using DigitalData.Core.Exceptions;
+using EnvelopeGenerator.Application.Common.Extensions;
+
+namespace EnvelopeGenerator.Application.Common.Query;
+
+/// <summary>
+/// 
+/// </summary>
+public record EnvelopeReceiverQueryBase : EnvelopeReceiverQueryBase<EnvelopeQueryBase, ReceiverQueryBase>;
+
+/// <summary>
+/// 
+/// </summary>
+/// <typeparam name="TEnvelopeQuery"></typeparam>
+/// <typeparam name="TReceiverQuery"></typeparam>
+public record EnvelopeReceiverQueryBase<TEnvelopeQuery, TReceiverQuery>
+    where TEnvelopeQuery : EnvelopeQueryBase, new()
+    where TReceiverQuery : ReceiverQueryBase, new()
+{
+    private string? _key;
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public virtual string? Key
+    {
+        get => _key;
+        set
+        {
+            if (value is null)
+            {
+                _key = null;
+                return;
+            }
+
+            (string? EnvelopeUuid, string? ReceiverSignature) = value.DecodeEnvelopeReceiverId();
+            if (string.IsNullOrEmpty(EnvelopeUuid) || string.IsNullOrEmpty(ReceiverSignature))
+                throw new BadRequestException("Der EnvelopeReceiverKey muss ein gültiger Base64-kodierter String sein, der die EnvelopeUuid und die ReceiverSignature enthält.");
+
+            Envelope = new TEnvelopeQuery()
+            {
+                Uuid = EnvelopeUuid
+            };
+            Receiver = new TReceiverQuery()
+            {
+                Signature = ReceiverSignature
+            };
+            _key = value;
+        }
+    }
+
+    /// <summary>
+    /// Repräsentiert eine Abfrage für Umschläge.
+    /// </summary>
+    public virtual TEnvelopeQuery Envelope { get; set; } = new();
+
+    /// <summary>
+    /// Stellt eine Abfrage dar, um die Details eines Empfängers zu lesen.
+    /// um spezifische Informationen über einen Empfänger abzurufen.
+    /// </summary>
+    public virtual TReceiverQuery Receiver { get; set; } = new();
+}

EnvelopeGenerator.Application/Common/Query/MappingProfile.cs

@@ -0,0 +1,20 @@
+using AutoMapper;
+using EnvelopeGenerator.Domain.Entities;
+
+namespace EnvelopeGenerator.Application.Common.Query;
+
+/// <summary>
+/// 
+/// </summary>
+public class MappingProfile : Profile
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public MappingProfile()
+    {
+        CreateMap<EnvelopeQueryBase, Envelope>();
+        CreateMap<ReceiverQueryBase, Receiver>();
+        CreateMap<EnvelopeReceiverQueryBase, EnvelopeReceiver>();
+    }
+}