Add MedMind recovery and Steam authentication

Services/UserService.cs

@@ -3,6 +3,8 @@ using System.Threading.Tasks;
 using GameAuthApi.Models;
 using Microsoft.Extensions.Configuration;
 using MongoDB.Driver;
+using System;
+using System.Linq;
 
 namespace GameAuthApi.Services;
 
@@ -20,6 +22,19 @@ public class UserService
     public virtual async Task<User> GetByUsernameAsync(string username) =>
         await _users.Find(u => u.Username == username).FirstOrDefaultAsync();
 
+    public virtual async Task<User> GetByLoginAsync(string login)
+    {
+        var normalized = Normalize(login);
+        return await _users.Find(u =>
+            u.NormalizedUsername == normalized ||
+            u.NormalizedEmail == normalized ||
+            u.Username == login ||
+            u.Email == login).FirstOrDefaultAsync();
+    }
+
+    public virtual async Task<User> GetByIdAsync(string id) =>
+        await _users.Find(u => u.Id == id).FirstOrDefaultAsync();
+
     public virtual async Task<List<User>> GetAllAsync() =>
         await _users.Find(_ => true).ToListAsync();
 
@@ -29,9 +44,52 @@ public class UserService
         return result.DeletedCount > 0;
     }
 
-    public virtual async Task CreateAsync(User user) =>
+    public virtual async Task CreateAsync(User user)
+    {
+        ApplyNormalizedFields(user);
         await _users.InsertOneAsync(user);
+    }
 
-    public virtual async Task UpdateAsync(User user) =>
+    public virtual async Task UpdateAsync(User user)
+    {
+        ApplyNormalizedFields(user);
         await _users.ReplaceOneAsync(u => u.Id == user.Id, user);
-}
+    }
+
+    public virtual async Task EnsureIndexesAsync()
+    {
+        var username = new CreateIndexModel<User>(
+            Builders<User>.IndexKeys.Ascending(u => u.NormalizedUsername),
+            new CreateIndexOptions { Unique = true, Sparse = true, Name = "normalized_username_unique" });
+        var email = new CreateIndexModel<User>(
+            Builders<User>.IndexKeys.Ascending(u => u.NormalizedEmail),
+            new CreateIndexOptions { Unique = true, Sparse = true, Name = "normalized_email_unique" });
+        await _users.Indexes.CreateManyAsync(new[] { username, email });
+    }
+
+    public virtual async Task BackfillNormalizedFieldsAsync()
+    {
+        var users = await _users.Find(_ => true).ToListAsync();
+        var duplicateUsername = users.GroupBy(u => Normalize(u.Username)).FirstOrDefault(g => g.Key != string.Empty && g.Count() > 1);
+        var duplicateEmail = users.Where(u => !string.IsNullOrWhiteSpace(u.Email)).GroupBy(u => Normalize(u.Email)).FirstOrDefault(g => g.Count() > 1);
+        if (duplicateUsername != null || duplicateEmail != null)
+            throw new InvalidOperationException("Duplicate normalized usernames or emails must be resolved before starting the authentication service.");
+        foreach (var user in users)
+        {
+            var normalizedUsername = Normalize(user.Username);
+            var normalizedEmail = string.IsNullOrWhiteSpace(user.Email) ? null : Normalize(user.Email);
+            if (user.NormalizedUsername == normalizedUsername && user.NormalizedEmail == normalizedEmail) continue;
+            user.NormalizedUsername = normalizedUsername;
+            user.NormalizedEmail = normalizedEmail;
+            await _users.ReplaceOneAsync(u => u.Id == user.Id, user);
+        }
+    }
+
+    public static string Normalize(string value) => value?.Trim().ToUpperInvariant() ?? string.Empty;
+
+    private static void ApplyNormalizedFields(User user)
+    {
+        user.NormalizedUsername = Normalize(user.Username);
+        user.NormalizedEmail = string.IsNullOrWhiteSpace(user.Email) ? null : Normalize(user.Email);
+    }
+}