Initial and done prolly

lib/db/crud/user_crud.dart

@@ -0,0 +1,84 @@
+part of '../database.dart';
+
+extension UserCrud on AppDatabase {
+  String hashPassword(String password) {
+    final passwordBytes = utf8.encode(password);
+    final hashedPassword = sha512224.convert(passwordBytes);
+    return hashedPassword.toString();
+  }
+
+  Future<UserData?> addUser({
+    required String login,
+    required String password,
+  }) async {
+    return await managers.user.createReturningOrNull((c) => c(
+          login: login,
+          password: hashPassword(password),
+        ));
+  }
+
+  Future<List<UserData>> getUsers() async {
+    return await managers.user.get();
+  }
+
+  Future<bool> anyUserExists() async {
+    return await managers.user.exists();
+  }
+
+  Future<UserData?> findUser({
+    required String login,
+    required String password,
+  }) async {
+    return await managers.user
+        .filter((f) => f.login(login))
+        .filter((f) => f.password(hashPassword(password)))
+        .getSingleOrNull();
+  }
+
+  Future<UserData> getUser(UserData user) async {
+    return await managers.user.filter((f) => f.id(user.id)).getSingle();
+  }
+
+  Future<bool> updateUser(
+    UserData currentUser,
+    UserData updatedUser, {
+    String? login,
+    String? password,
+  }) async {
+    if (currentUser.id == updatedUser.id) {
+      return false;
+    }
+
+    await managers.user.filter((f) => f.id(updatedUser.id)).update((u) => u(
+          login: Value.absentIfNull(login),
+          password: Value.absentIfNull(
+              password != null ? hashPassword(password) : null),
+        ));
+
+    return true;
+  }
+
+  Future<bool> updateUserPassword(
+    UserData user, {
+    required String password,
+  }) async {
+    await managers.user.filter((f) => f.id(user.id)).update((u) => u(
+          password: Value(hashPassword(password)),
+        ));
+
+    return true;
+  }
+
+  Future<bool> deleteUser(UserData user) async {
+    final usersCount = await managers.user.count();
+    if (usersCount == 0) {
+      return false;
+    }
+    final deletedCount = await managers.user
+        .filter(
+          (f) => f.id(user.id),
+        )
+        .delete();
+    return deletedCount != 0;
+  }
+}