Add ReceiverService and enhance DocumentService

Added `ReceiverService` to the dependency injection container in `Program.cs` and implemented its functionality for fetching receiver email suggestions via API.

Enhanced `DocumentService` with a new method `GetSenderDocumentDetailsByEnvelopeIdAsync` to fetch sender document details by envelope ID. Introduced JSON handling improvements with `JsonSerializerOptions`.

These changes improve support for receiver-related operations and extend document-related capabilities.

EnvelopeGenerator.Server/EnvelopeGenerator.Server.Client/Program.cs

@@ -42,6 +42,7 @@ builder.Services.AddScoped<SignatureCacheService>();
 builder.Services.AddSingleton<AppVersionService>();
 builder.Services.AddScoped<EnvelopeService>();
 builder.Services.AddScoped<LocalizationService>();
+builder.Services.AddScoped<ReceiverService>();
 
 // UI Preferences & Theme
 builder.Services.AddScoped<UserPreferencesService>();

EnvelopeGenerator.Server/EnvelopeGenerator.Server.Client/Services/DocumentService.cs

@@ -1,10 +1,14 @@
 using System.Net;
 using System.Net.Http;
+using System.Net.Http.Json;
+using System.Text.Json;
+using EnvelopeGenerator.Application.Common.Dto;
 
 namespace EnvelopeGenerator.Server.Client.Services;
 
 public class DocumentService(IHttpClientFactory httpClientFactory)
 {
+    private static readonly JsonSerializerOptions _jsonOptions = new(JsonSerializerDefaults.Web);
 
     /// <summary>
     /// Fetches the PDF bytes for the given envelope key from the API.
@@ -29,4 +33,26 @@ public class DocumentService(IHttpClientFactory httpClientFactory)
         var bytes = await response.Content.ReadAsByteArrayAsync(cancel);
         return bytes;
     }
+
+    /// <summary>
+    /// Fetches sender document details (including signature elements) by envelope id.
+    /// Uses GET /api/Document?EnvelopeId={envelopeId}.
+    /// </summary>
+    public async Task<DocumentDto?> GetSenderDocumentDetailsByEnvelopeIdAsync(int envelopeId, CancellationToken cancel = default)
+    {
+        using var http = httpClientFactory.CreateClient("EnvelopeGenerator.Server");
+        var response = await http.GetAsync($"/api/Document?EnvelopeId={envelopeId}", cancel);
+
+        if (!response.IsSuccessStatusCode)
+        {
+            var statusCode = (int)response.StatusCode;
+            var reasonPhrase = response.ReasonPhrase ?? "Unknown error";
+            throw new HttpRequestException(
+                $"Failed to load sender document details. Status: {statusCode} ({reasonPhrase})",
+                null,
+                response.StatusCode);
+        }
+
+        return await response.Content.ReadFromJsonAsync<DocumentDto>(_jsonOptions, cancel);
+    }
 }

EnvelopeGenerator.Server/EnvelopeGenerator.Server.Client/Services/ReceiverService.cs

@@ -0,0 +1,29 @@
+using System.Net.Http.Json;
+using System.Text.Json;
+
+namespace EnvelopeGenerator.Server.Client.Services;
+
+public class ReceiverService(IHttpClientFactory httpClientFactory)
+{
+    private static readonly JsonSerializerOptions JsonOptions = new(JsonSerializerDefaults.Web);
+
+    /// <summary>
+    /// Fetches receiver email suggestions from sender-authorized API.
+    /// Calls GET /api/Receiver?EmailAddressSearch={term}&onlyEmailAddress=true.
+    /// </summary>
+    public async Task<IReadOnlyList<string>> SearchReceiverEmailsAsync(string searchTerm, CancellationToken cancel = default)
+    {
+        if (string.IsNullOrWhiteSpace(searchTerm))
+            return [];
+
+        using var http = httpClientFactory.CreateClient("EnvelopeGenerator.Server");
+        var url = $"/api/Receiver?EmailAddressSearch={Uri.EscapeDataString(searchTerm)}&onlyEmailAddress=true";
+        var response = await http.GetAsync(url, cancel);
+
+        if (!response.IsSuccessStatusCode)
+            return [];
+
+        var emails = await response.Content.ReadFromJsonAsync<List<string>>(JsonOptions, cancel);
+        return emails ?? [];
+    }
+}

EnvelopeGenerator.Server/EnvelopeGenerator.Server/Program.cs

@@ -341,6 +341,7 @@ try
     builder.Services.AddScoped<EnvelopeGenerator.Server.Client.Services.ThemeService>();
     builder.Services.AddScoped<EnvelopeGenerator.Server.Client.Services.CustomImagesService>();
     builder.Services.AddScoped<EnvelopeGenerator.Server.Client.Services.LocalizationService>();
+    builder.Services.AddScoped<EnvelopeGenerator.Server.Client.Services.ReceiverService>();
 
     // Business Services (Server specific)
     builder.Services.AddScoped<DocumentService>();