Add self-service account management commands (delete, update username/email/password/profile)

web/backend/Features/Features.Auth/Commands/UpdateProfile/UpdateProfileHandler.cs

@@ -0,0 +1,38 @@
+using Domain.Exceptions;
+using Features.Auth.Dtos;
+using Features.Auth.Identity;
+using MediatR;
+using Microsoft.AspNetCore.Identity;
+
+namespace Features.Auth.Commands.UpdateProfile;
+
+/// <summary>
+///     Handles <see cref="UpdateProfileCommand" /> via <see cref="UserManager{TUser}" />. First/last name
+///     and date of birth aren't tracked by any Identity-specific store interface, so the mutated
+///     <see cref="ApplicationUser" /> is saved directly through <see cref="UserManager{TUser}.UpdateAsync" />.
+/// </summary>
+public class UpdateProfileHandler(UserManager<ApplicationUser> userManager)
+    : IRequestHandler<UpdateProfileCommand, UpdateProfilePayload>
+{
+    /// <exception cref="NotFoundException">Thrown when the account does not exist.</exception>
+    /// <exception cref="ConflictException">Thrown when the update otherwise fails.</exception>
+    public async Task<UpdateProfilePayload> Handle(
+        UpdateProfileCommand request,
+        CancellationToken cancellationToken
+    )
+    {
+        ApplicationUser user =
+            await userManager.FindByIdAsync(request.UserAccountId.ToString())
+            ?? throw new NotFoundException("User account not found");
+
+        user.FirstName = request.FirstName;
+        user.LastName = request.LastName;
+        user.DateOfBirth = request.DateOfBirth;
+
+        IdentityResult result = await userManager.UpdateAsync(user);
+        if (!result.Succeeded)
+            throw new ConflictException(string.Join("; ", result.Errors.Select(e => e.Description)));
+
+        return new UpdateProfilePayload(user.Id, user.FirstName, user.LastName, user.DateOfBirth);
+    }
+}