import 'dart:convert';

import 'package:shelf/shelf.dart';
import 'package:shelf_router/shelf_router.dart';

import '../../middleware/error_handler.dart';
import '../../shared/api_response.dart';
import 'auth_service.dart';

/// Auth module routes: register, login, refresh, logout, delete account.
class AuthRoutes {
  final AuthService _authService;

  AuthRoutes(this._authService);

  Router get router {
    final router = Router();

    router.post('/register', _register);
    router.post('/login', _login);
    router.post('/refresh', _refresh);
    router.post('/logout', _logout);
    router.delete('/account', _deleteAccount);

    return router;
  }

  // ── Handlers ────────────────────────────────────────────────────────

  Future<Response> _register(Request request) async {
    final body = jsonDecode(await request.readAsString()) as Map<String, dynamic>;

    final email = body['email'] as String?;
    final password = body['password'] as String?;
    final displayName = body['display_name'] as String?;

    if (email == null || password == null || displayName == null) {
      throw ApiException.badRequest(
        'Missing required fields: email, password, display_name',
      );
    }

    if (password.length < 8) {
      throw ApiException.badRequest('Password must be at least 8 characters');
    }

    final tokens = await _authService.register(
      email: email,
      password: password,
      displayName: displayName,
    );

    return ApiResponse.created(tokens, message: 'Account created');
  }

  Future<Response> _login(Request request) async {
    final body = jsonDecode(await request.readAsString()) as Map<String, dynamic>;

    final email = body['email'] as String?;
    final password = body['password'] as String?;

    if (email == null || password == null) {
      throw ApiException.badRequest('Missing required fields: email, password');
    }

    final tokens = await _authService.login(
      email: email,
      password: password,
    );

    return ApiResponse.success(tokens, message: 'Login successful');
  }

  Future<Response> _refresh(Request request) async {
    final body = jsonDecode(await request.readAsString()) as Map<String, dynamic>;

    final refreshToken = body['refresh_token'] as String?;
    if (refreshToken == null) {
      throw ApiException.badRequest('Missing required field: refresh_token');
    }

    final tokens = await _authService.refresh(refreshToken);
    return ApiResponse.success(tokens);
  }

  Future<Response> _logout(Request request) async {
    final body = jsonDecode(await request.readAsString()) as Map<String, dynamic>;

    final refreshToken = body['refresh_token'] as String?;
    if (refreshToken == null) {
      throw ApiException.badRequest('Missing required field: refresh_token');
    }

    await _authService.logout(refreshToken);
    return ApiResponse.success(null, message: 'Logged out successfully');
  }

  Future<Response> _deleteAccount(Request request) async {
    final userId = request.context['userId'] as String;
    await _authService.deleteAccount(userId);
    return ApiResponse.success(null, message: 'Account deleted');
  }
}