feat: перелопатил синхронизацию преподавателей

backend/UniVerse.Infrastructure/ExternalServices/MicrosoftAuthClient.cs

@@ -0,0 +1,52 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Identity.Client;
+using UniVerse.Application.Interfaces;
+using UniVerse.Domain.Exceptions;
+
+namespace UniVerse.Infrastructure.ExternalServices;
+
+public class MicrosoftAuthClient : IMicrosoftAuthClient
+{
+    private readonly IConfiguration _config;
+
+    public MicrosoftAuthClient(IConfiguration config)
+    {
+        _config = config;
+    }
+
+    public async Task<MicrosoftTokenResult> ExchangeAuthorizationCodeAsync(
+        string authorizationCode,
+        string redirectUri,
+        CancellationToken cancellationToken = default)
+    {
+        var tenantId = _config["AzureAd:TenantId"];
+        var clientId = _config["AzureAd:ClientId"];
+        var clientSecret = _config["AzureAd:ClientSecret"];
+        var instance = _config["AzureAd:Instance"] ?? "https://login.microsoftonline.com/";
+
+        if (string.IsNullOrWhiteSpace(tenantId)
+            || string.IsNullOrWhiteSpace(clientId)
+            || string.IsNullOrWhiteSpace(clientSecret))
+            throw new UnauthorizedException("Аутентификация Microsoft не настроена (AzureAd:TenantId/ClientId/ClientSecret).");
+
+        var authority = $"{instance.TrimEnd('/')}/{tenantId}";
+
+        var app = ConfidentialClientApplicationBuilder.Create(clientId)
+            .WithClientSecret(clientSecret)
+            .WithAuthority(new Uri(authority))
+            .WithRedirectUri(redirectUri)
+            .Build();
+
+        try
+        {
+            var result = await app.AcquireTokenByAuthorizationCode(["User.Read"], authorizationCode)
+                .ExecuteAsync(cancellationToken);
+
+            return new MicrosoftTokenResult(result.IdToken);
+        }
+        catch (MsalException ex)
+        {
+            throw new UnauthorizedException($"Ошибка аутентификации Microsoft: {ex.Message}");
+        }
+    }
+}