Add read-only sharing and viewing functionality

Introduced the ability to share envelopes in read-only mode and view them via a dedicated page. Added `ShareEnvelopeReadOnlyAsync` in `AuthService.cs` to handle sharing logic. Updated `ReceiverPage.razor` with a "Share" button, popup UI, and validation for sharing inputs. Created `ReceiverReadOnlyPage.razor` for read-only document viewing with error handling and lifecycle management.

Added `EnvelopeKeyRedirectController.cs` to support legacy link redirection. Enhanced `ReadOnlyController.cs` to support envelope sharing with improved logging and `IMediator` integration. Improved state management, validation, and error handling across components. Performed general code cleanup and UI enhancements for better user experience.

EnvelopeGenerator.Server/EnvelopeGenerator.Server.Client/Services/AuthService.cs

@@ -86,6 +86,18 @@ public class AuthService(IHttpClientFactory httpClientFactory)
         return response.IsSuccessStatusCode;
     }
 
+    /// <summary>
+    /// Shares the current envelope in read-only mode for the specified receiver and expiration date.
+    /// Calls POST /api/readonly/{envelopeKey}.
+    /// </summary>
+    public async Task<bool> ShareEnvelopeReadOnlyAsync(string envelopeKey, string receiverMail, DateTime dateValid, CancellationToken cancel = default)
+    {
+        using var http = CreateDefaultClient();
+        var payload = new { receiverMail, dateValid };
+        var response = await http.PostAsJsonAsync($"/api/readonly/{Uri.EscapeDataString(envelopeKey)}", payload, cancel);
+        return response.IsSuccessStatusCode;
+    }
+
     /// <summary>
     /// Removes the per-envelope receiver cookie for the given envelope key.
     /// Calls POST /api/auth/logout/envelope/{envelopeKey}.

EnvelopeGenerator.Server/EnvelopeGenerator.Server/Components/Pages/ReceiverPage.razor

@@ -5,12 +5,15 @@
 @using EnvelopeGenerator.Server.Client.Models
 @using EnvelopeGenerator.Server.Client.Models.Constants
 @using EnvelopeGenerator.Server.Client.Services
+@using EnvelopeGenerator.Application.Common.Extensions
 @using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiver
 @using EnvelopeGenerator.Application.EnvelopeReceivers.Queries
+@using EnvelopeGenerator.Domain.Constants
 @using Microsoft.JSInterop
 @using DevExpress.Blazor
 @using System.Drawing
 @using System.Security.Claims
+@using System.ComponentModel.DataAnnotations
 @using Microsoft.Extensions.Caching.Memory
 @using MediatR
 @using EnvelopeGenerator.Server.Extensions
@@ -130,6 +133,20 @@
                         </button>
                     }
 
+                    @if (!(_envelopeReceiver?.Envelope?.ReadOnly ?? false))
+                    {
+                        <button class="pdf-toolbar__btn"
+                                @onclick="OpenSharePopup"
+                                title="Dokument teilen"
+                                style="flex-shrink: 0;">
+                            <svg xmlns="http://www.w3.org/2000/svg" width="14" height="14" fill="currentColor" viewBox="0 0 16 16">
+                                <path d="M13.5 1a1.5 1.5 0 1 0 1.415 2H15a1.5 1.5 0 0 0-1.5-2zm-11 5a1.5 1.5 0 1 0 1.415 2H4a1.5 1.5 0 0 0-1.5-2zm11 5a1.5 1.5 0 1 0 1.415 2H15a1.5 1.5 0 0 0-1.5-2z"/>
+                                <path d="M2.854 7.646a.5.5 0 0 1 .0-.707l9-5a.5.5 0 1 1 .486.874l-9 5a.5.5 0 0 1-.486-.167zm0 .708a.5.5 0 0 1 .486-.167l9 5a.5.5 0 0 1-.486.874l-9-5a.5.5 0 0 1 0-.707z"/>
+                            </svg>
+                            <span class="pdf-toolbar__btn-text">Teilen</span>
+                        </button>
+                    }
+
                     <button class="pdf-toolbar__btn"
                             @onclick="LogoutAsync"
                             disabled="@_isLoggingOut"
@@ -358,6 +375,57 @@
     </FooterContentTemplate>
 </DxPopup>
 
+<DxPopup @bind-Visible="_sharePopupVisible"
+         HeaderText="Dokument teilen"
+         Width="520px"
+         MaxWidth="95vw"
+         ShowFooter="true"
+         CloseOnOutsideClick="true">
+    <BodyContentTemplate>
+        <div class="mb-3">
+            <label class="form-label" for="rp-share-mail" style="font-size: 0.9rem; font-weight: 500;">E-Mail</label>
+            <input id="rp-share-mail"
+                   class="form-control"
+                   placeholder="user@mail.com"
+                   value="@_shareReceiverMail"
+                   @oninput="args => _shareReceiverMail = args.Value?.ToString() ?? string.Empty" />
+        </div>
+
+        <div class="mb-1">
+            <label class="form-label" for="rp-share-date" style="font-size: 0.9rem; font-weight: 500;">Gultig bis</label>
+            <input id="rp-share-date"
+                   class="form-control"
+                   type="date"
+                   min="@DateTime.Today.AddDays(1).ToString("yyyy-MM-dd")"
+                   max="@DateTime.Today.AddDays(90).ToString("yyyy-MM-dd")"
+                   value="@_shareDateValid.ToString("yyyy-MM-dd")"
+                   @oninput="OnShareDateChanged" />
+        </div>
+
+        @if (!string.IsNullOrWhiteSpace(_shareMessage))
+        {
+            <div class="mt-3 alert @(_shareMessageIsError ? "alert-danger" : "alert-success") mb-0" role="alert">
+                @_shareMessage
+            </div>
+        }
+    </BodyContentTemplate>
+    <FooterContentTemplate>
+        <div class="d-flex justify-content-end gap-2 w-100">
+            <button class="btn btn-outline-secondary"
+                    @onclick="CloseSharePopup"
+                    disabled="@_isSharing">
+                Schliessen
+            </button>
+            <button class="btn btn-primary"
+                    @onclick="ShareEnvelopeAsync"
+                    disabled="@_isSharing"
+                    style="background: linear-gradient(135deg, #4F46E5 0%, #4338CA 100%); border: none;">
+                @(_isSharing ? "Senden..." : "Senden")
+            </button>
+        </div>
+    </FooterContentTemplate>
+</DxPopup>
+
 @code {
     // ----- Constants -----
     const string SignatureTabDraw  = "draw";
@@ -404,6 +472,14 @@
     string _signaturePlace         = string.Empty;
     bool _isLoggingOut             = false;
 
+    // ----- Share popup state -----
+    bool _sharePopupVisible        = false;
+    bool _isSharing                = false;
+    string _shareReceiverMail      = string.Empty;
+    DateTime _shareDateValid       = DateTime.Today.AddDays(7);
+    string? _shareMessage;
+    bool _shareMessageIsError      = false;
+
     async Task LogoutAsync()
     {
         if (_isLoggingOut || string.IsNullOrWhiteSpace(EnvelopeKey))
@@ -424,6 +500,85 @@
         Navigation.NavigateTo($"/envelope/login/{Uri.EscapeDataString(EnvelopeKey)}", forceLoad: true);
     }
 
+    void OpenSharePopup()
+    {
+        _shareReceiverMail = string.Empty;
+        _shareDateValid = DateTime.Today.AddDays(7);
+        _shareMessage = null;
+        _shareMessageIsError = false;
+        _sharePopupVisible = true;
+    }
+
+    void CloseSharePopup()
+    {
+        if (_isSharing)
+            return;
+
+        _sharePopupVisible = false;
+    }
+
+    void OnShareDateChanged(Microsoft.AspNetCore.Components.ChangeEventArgs args)
+    {
+        if (DateTime.TryParse(args.Value?.ToString(), out var parsedDate))
+            _shareDateValid = parsedDate.Date;
+    }
+
+    async Task ShareEnvelopeAsync()
+    {
+        if (_isSharing)
+            return;
+
+        var email = _shareReceiverMail.Trim();
+        if (string.IsNullOrWhiteSpace(email) || !new EmailAddressAttribute().IsValid(email))
+        {
+            _shareMessage = "Bitte geben Sie eine gultige E-Mail-Adresse ein.";
+            _shareMessageIsError = true;
+            return;
+        }
+
+        var minDate = DateTime.Today.AddDays(1);
+        var maxDate = DateTime.Today.AddDays(90);
+        if (_shareDateValid.Date < minDate || _shareDateValid.Date > maxDate)
+        {
+            _shareMessage = "Bitte wahlen Sie ein Datum zwischen morgen und 90 Tagen.";
+            _shareMessageIsError = true;
+            return;
+        }
+
+        _isSharing = true;
+        _shareMessage = null;
+        _shareMessageIsError = false;
+        await InvokeAsync(StateHasChanged);
+
+        try
+        {
+            var shared = await AuthService.ShareEnvelopeReadOnlyAsync(EnvelopeKey!, email, _shareDateValid.Date);
+            if (shared)
+            {
+                _shareMessage = "Dokument wurde erfolgreich als Nur-Lesen freigegeben.";
+                _shareMessageIsError = false;
+                _shareReceiverMail = string.Empty;
+                _shareDateValid = DateTime.Today.AddDays(7);
+            }
+            else
+            {
+                _shareMessage = "Freigabe fehlgeschlagen. Bitte versuchen Sie es erneut.";
+                _shareMessageIsError = true;
+            }
+        }
+        catch (Exception ex)
+        {
+            Logger.LogWarning(ex, "Failed to share envelope in read-only mode for {EnvelopeKey}", EnvelopeKey);
+            _shareMessage = "Freigabe fehlgeschlagen. Bitte versuchen Sie es erneut.";
+            _shareMessageIsError = true;
+        }
+        finally
+        {
+            _isSharing = false;
+            await InvokeAsync(StateHasChanged);
+        }
+    }
+
     // ----- Lifecycle -----
     protected override async Task OnInitializedAsync()
     {
@@ -434,6 +589,12 @@
             return;
         }
 
+        if (EnvelopeKey.TryDecode(out var decodedKeys) && decodedKeys.GetEncodeType() == EncodeType.EnvelopeReceiverReadOnly)
+        {
+            Navigation.NavigateTo($"/envelope/readonly/{Uri.EscapeDataString(EnvelopeKey)}", forceLoad: true);
+            return;
+        }
+
         // Authorization — same pattern as EnvelopeReceiverPage
         _receiverUser = await ReceiverAuthorizationService.AuthorizeAsync(EnvelopeKey);
         if (_receiverUser is null)

EnvelopeGenerator.Server/EnvelopeGenerator.Server/Components/Pages/ReceiverReadOnlyPage.razor

@@ -0,0 +1,188 @@
+@page "/envelope/readonly/{ReadOnlyKey}"
+@rendermode InteractiveServer
+@using DevExpress.Blazor.Reporting
+@using DevExpress.XtraReports.UI
+@using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly
+@using EnvelopeGenerator.Application.Common.Extensions
+@using EnvelopeGenerator.Application.Common.Interfaces.Services
+@using EnvelopeGenerator.Domain.Constants
+@inject EnvelopeGenerator.Server.Client.Services.AppVersionService AppVersion
+@inject ILogger<ReceiverReadOnlyPage> Logger
+@inject IEnvelopeReceiverReadOnlyService ReadOnlyService
+@inject IEnvelopeReceiverService EnvelopeReceiverService
+@inject IEnvelopeHistoryService HistoryService
+@implements IDisposable
+
+<link href="_content/DevExpress.Blazor.Themes/blazing-berry.bs5.min.css" rel="stylesheet" />
+<link href="_content/DevExpress.Blazor.Reporting.Viewer/css/dx-blazor-reporting-components.bs5.css" rel="stylesheet" />
+<link href="@AppVersion.GetVersionedUrl("css/envelope-viewer.css")" rel="stylesheet" />
+
+<div class="envelope-viewer-layout">
+    <div class="envelope-action-bar">
+        <div class="envelope-action-bar__inner" style="padding: 0.5rem 1.25rem;">
+            <div style="display:flex; align-items:center; justify-content:space-between; gap:1rem;">
+                <div style="font-weight:600; color:#1f2937;">Dokumentansicht (Nur Lesen)</div>
+                @if (_readOnly is not null)
+                {
+                    <div style="font-size:0.8rem; color:#6b7280;">Gultig bis: @_readOnly.DateValid.ToString("dd.MM.yyyy")</div>
+                }
+            </div>
+        </div>
+    </div>
+
+    <div class="envelope-content" style="padding:0; overflow:hidden;">
+        @if (_isLoading)
+        {
+            <div class="d-flex justify-content-center align-items-center h-100">
+                <div class="text-center">
+                    <div class="spinner-border text-white mb-3" style="width:3.5rem; height:3.5rem;" role="status"></div>
+                    <p class="text-white fw-semibold">Dokument wird geladen...</p>
+                </div>
+            </div>
+        }
+        else if (!string.IsNullOrWhiteSpace(_errorMessage))
+        {
+            <div class="error-container">
+                <div class="alert alert-danger shadow-lg mb-0">
+                    <h5 class="mb-2">Dokument nicht verfugbar</h5>
+                    <p class="mb-0">@_errorMessage</p>
+                </div>
+            </div>
+        }
+        else if (_isExpired)
+        {
+            <div class="error-container">
+                <div class="alert alert-warning shadow-lg mb-0">
+                    <h5 class="mb-2">Freigabe abgelaufen</h5>
+                    <p class="mb-0">Der Zeitraum fur diese Nur-Lesen-Freigabe ist abgelaufen.</p>
+                </div>
+            </div>
+        }
+        else if (_report is not null)
+        {
+            <DxReportViewer @ref="_reportViewer"
+                            Report="_report"
+                            RootCssClasses="w-100 h-100" />
+        }
+    </div>
+</div>
+
+@code {
+    [Parameter] public string? ReadOnlyKey { get; set; }
+
+    bool _isLoading = true;
+    bool _isExpired = false;
+    string? _errorMessage;
+    EnvelopeReceiverReadOnlyDto? _readOnly;
+
+    DxReportViewer? _reportViewer;
+    XtraReport? _report;
+
+    protected override async Task OnInitializedAsync()
+    {
+        if (string.IsNullOrWhiteSpace(ReadOnlyKey))
+        {
+            _errorMessage = "Freigabe-Schlussel fehlt.";
+            _isLoading = false;
+            return;
+        }
+
+        if (!ReadOnlyKey.TryDecode(out var decodedKeys) || decodedKeys.GetEncodeType() != EncodeType.EnvelopeReceiverReadOnly)
+        {
+            _errorMessage = "Ungultiger Freigabe-Link.";
+            _isLoading = false;
+            return;
+        }
+
+        try
+        {
+            var readOnlyId = decodedKeys.ParseReadOnlyId();
+            var readOnlyRes = await ReadOnlyService.ReadByIdAsync(readOnlyId);
+            if (readOnlyRes.IsFailed)
+            {
+                _errorMessage = "Freigabe konnte nicht geladen werden.";
+                _isLoading = false;
+                return;
+            }
+
+            _readOnly = readOnlyRes.Data;
+
+            if (DateTime.Now > _readOnly.DateValid)
+            {
+                _isExpired = true;
+                _isLoading = false;
+                return;
+            }
+
+            if (_readOnly.Envelope is null || _readOnly.Receiver is null)
+            {
+                _errorMessage = "Freigabe ist unvollstandig.";
+                _isLoading = false;
+                return;
+            }
+
+            var erRes = await EnvelopeReceiverService.ReadByUuidSignatureAsync(_readOnly.Envelope.Uuid, _readOnly.Receiver.Signature);
+            if (erRes.IsFailed)
+            {
+                _errorMessage = "Dokument wurde nicht gefunden.";
+                _isLoading = false;
+                return;
+            }
+
+            var envelopeReceiver = erRes.Data;
+            var documentBytes = envelopeReceiver.Envelope?.Documents?.FirstOrDefault()?.ByteData;
+            if (documentBytes is not { Length: > 0 })
+            {
+                _errorMessage = "Dokumentdaten konnten nicht geladen werden.";
+                _isLoading = false;
+                return;
+            }
+
+            _report = BuildReport(documentBytes);
+
+            try
+            {
+                var historyResult = await HistoryService.RecordAsync((int)_readOnly.EnvelopeId, _readOnly.AddedWho, EnvelopeStatus.EnvelopeViewed);
+                if (historyResult.IsFailed)
+                    Logger.LogWarning("Failed to record EnvelopeViewed history for read-only key {ReadOnlyKey}", ReadOnlyKey);
+            }
+            catch (Exception ex)
+            {
+                Logger.LogWarning(ex, "Failed to record read-only history for {ReadOnlyKey}", ReadOnlyKey);
+            }
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError(ex, "Unexpected error in read-only page for {ReadOnlyKey}", ReadOnlyKey);
+            _errorMessage = "Beim Laden ist ein unerwarteter Fehler aufgetreten.";
+        }
+
+        _isLoading = false;
+    }
+
+    static XtraReport BuildReport(byte[] pdfBytes)
+    {
+        var report = new XtraReport
+        {
+            PaperKind = DevExpress.Drawing.Printing.DXPaperKind.A4,
+            Landscape = false,
+            Margins = new System.Drawing.Printing.Margins(0, 0, 0, 0)
+        };
+
+        var detail = new DetailBand { HeightF = 0f };
+        report.Bands.Add(detail);
+
+        detail.Controls.Add(new XRPdfContent
+        {
+            Source = pdfBytes,
+            GenerateOwnPages = true
+        });
+
+        return report;
+    }
+
+    public void Dispose()
+    {
+        _report?.Dispose();
+    }
+}

EnvelopeGenerator.Server/EnvelopeGenerator.Server/Controllers/EnvelopeKeyRedirectController.cs

@@ -0,0 +1,18 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace EnvelopeGenerator.Server.Controllers;
+
+/// <summary>
+/// Redirects legacy envelope key links to Blazor routes.
+/// </summary>
+[ApiExplorerSettings(IgnoreApi = true)]
+[Route("EnvelopeKey")]
+public class EnvelopeKeyRedirectController : Controller
+{
+    /// <summary>
+    /// Redirects /EnvelopeKey/{*path} links to /envelope/{path}.
+    /// </summary>
+    [HttpGet("{*path}")]
+    public IActionResult RedirectToEnvelopePath([FromRoute] string path)
+        => Redirect($"/envelope/{path}");
+}

EnvelopeGenerator.Server/EnvelopeGenerator.Server/Controllers/ReadOnlyController.cs

@@ -1,8 +1,10 @@
 using DigitalData.Core.Abstraction.Application.DTO;
 using EnvelopeGenerator.Application.Common.Dto.EnvelopeReceiverReadOnly;
 using EnvelopeGenerator.Application.Common.Interfaces.Services;
+using EnvelopeGenerator.Application.EnvelopeReceivers.Queries;
 using EnvelopeGenerator.Domain.Constants;
-using EnvelopeGenerator.Server.Extensions;
+using MediatR;
+using System.Security.Claims;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using Newtonsoft.Json;
@@ -33,24 +35,36 @@ public class ReadOnlyController : ControllerBase
     }
 
     /// <summary>
-    /// Creates a new read-only receiver for the current envelope.
+    /// Creates a new read-only receiver for an envelope.
     /// </summary>
+    /// <param name="envelopeKey">Envelope key (uuid+signature encoded).</param>
     /// <param name="createDto">Creation payload.</param>
-    [HttpPost]
+    [HttpPost("{envelopeKey}")]
-    [Authorize(Policy = AuthPolicy.Receiver)]
+    [Authorize(Policy = AuthPolicy.SenderOrReceiver)]
     [Obsolete("Use MediatR")]
-    public async Task<IActionResult> CreateAsync([FromBody] EnvelopeReceiverReadOnlyCreateDto createDto)
+    public async Task<IActionResult> CreateAsync(
+        [FromRoute] string envelopeKey,
+        [FromBody] EnvelopeReceiverReadOnlyCreateDto createDto,
+        [FromServices] IMediator mediator,
+        CancellationToken cancel)
     {
-        var authReceiverMail = User.ReceiverMail();
+        var envelopeReceiver = await mediator.Send(new ReadEnvelopeReceiverQuery { Key = envelopeKey }, cancel);
-        if (authReceiverMail is null)
+        var authEnvelopeReceiver = envelopeReceiver.FirstOrDefault();
+
+        if (authEnvelopeReceiver?.Envelope is null)
+            return NotFound();
+
+        var addedWho = User.FindFirstValue(ClaimTypes.Email)
+            ?? authEnvelopeReceiver.Receiver?.EmailAddress;
+        if (string.IsNullOrWhiteSpace(addedWho))
         {
-            _logger.LogError("EmailAddress claim is not found in envelope-receiver-read-only creation process. Create DTO is:\n {dto}", JsonConvert.SerializeObject(createDto));
+            _logger.LogError("Receiver e-mail is missing in envelope-receiver-read-only creation process. Create DTO is:\n {dto}", JsonConvert.SerializeObject(createDto));
-            return Unauthorized();
+            return StatusCode(StatusCodes.Status500InternalServerError);
         }
 
-        var envelopeId = User.EnvelopeId();
+        var envelopeId = authEnvelopeReceiver.EnvelopeId;
 
-        createDto.AddedWho = authReceiverMail;
+        createDto.AddedWho = addedWho;
         createDto.EnvelopeId = envelopeId;
 
         var creationRes = await _readOnlyService.CreateAsync(createDto: createDto);

EnvelopeGenerator.Server/EnvelopeGenerator.Server/EnvelopeGenerator.Server.csproj

@@ -10,9 +10,9 @@
     <Authors>Digital Data GmbH</Authors>
     <Company>Digital Data GmbH</Company>
     <Product>EnvelopeGenerator.Server</Product>
-    <Version>1.2.0-beta</Version>
+    <Version>1.4.0-beta</Version>
-    <FileVersion>1.2.0.0</FileVersion>
+    <FileVersion>1.4.0.0</FileVersion>
-    <AssemblyVersion>1.2.0.0</AssemblyVersion>
+    <AssemblyVersion>1.4.0.0</AssemblyVersion>
     <Copyright>Copyright © 2026 Digital Data GmbH. All rights reserved.</Copyright>
 	<DocumentationFile>bin\$(Configuration)\$(TargetFramework)\$(AssemblyName).xml</DocumentationFile>
   </PropertyGroup>