import 'dart:convert';

import 'package:http/http.dart' as http;

import '../../config/api_config.dart';
import '../../models/user_profile.dart';
import '../../services/auth_service.dart';
import 'profile_api_exception.dart';

/// HTTP client for Postgres-backed profile API.
class UserProfileRemoteStore {
  UserProfileRemoteStore({http.Client? client}) : _client = client ?? http.Client();

  final http.Client _client;

  Future<UserProfile?> fetchProfile() async {
    final String? token = await AuthService.instance.getIdToken();
    if (token == null) {
      return null;
    }

    final http.Response response = await _client.get(
      Uri.parse('$apiBaseUrl/v1/me/profile'),
      headers: _authHeaders(token),
    );

    if (response.statusCode == 404) {
      return null;
    }
    if (response.statusCode != 200) {
      throw ProfileApiException(response.statusCode, response.body);
    }

    return _profileFromApi(
      jsonDecode(response.body) as Map<String, dynamic>,
    );
  }

  Future<UserProfile> pushProfile(UserProfile profile) async {
    final String? token = await AuthService.instance.getIdToken();
    if (token == null) {
      throw StateError('Not signed in');
    }

    final http.Response response = await _client.put(
      Uri.parse('$apiBaseUrl/v1/me/profile'),
      headers: _authHeaders(token),
      body: jsonEncode(profile.toApiJson()),
    );

    if (response.statusCode == 409) {
      final Map<String, dynamic> body =
          jsonDecode(response.body) as Map<String, dynamic>;
      throw ProfileConflictException(
        _profileFromApi(body['profile'] as Map<String, dynamic>),
      );
    }
    if (response.statusCode != 200) {
      throw ProfileApiException(response.statusCode, response.body);
    }

    return _profileFromApi(
      jsonDecode(response.body) as Map<String, dynamic>,
    );
  }

  Map<String, String> _authHeaders(String token) {
    return <String, String>{
      'Authorization': 'Bearer $token',
      'Content-Type': 'application/json',
      'Accept': 'application/json',
    };
  }

  UserProfile _profileFromApi(Map<String, dynamic> json) {
    return UserProfile(
      firebaseUid: json['firebaseUid'] as String,
      email: json['email'] as String?,
      displayName: json['displayName'] as String?,
      photoUrl: json['photoUrl'] as String?,
      locale: json['locale'] as String? ?? 'en',
      timezone: json['timezone'] as String?,
      onboardingCompleted: json['onboardingCompleted'] as bool? ?? false,
      revision: (json['revision'] as num).toInt(),
      updatedAt: DateTime.parse(json['updatedAt'] as String).toUtc(),
      lastSyncedAt: DateTime.now().toUtc(),
      dirty: false,
    );
  }
}