import 'dart:async';
import 'dart:developer';

import 'package:app_links/app_links.dart';
import 'package:easy_localization/easy_localization.dart';
import 'package:mc_common_app/config/routes.dart';
import 'package:mc_common_app/generated/locale_keys.g.dart';
import 'package:mc_common_app/utils/navigator.dart';
import 'package:mc_common_app/utils/utils.dart';
import 'package:mc_common_app/view_models/ad_view_model.dart';
import 'package:provider/provider.dart';

/// Handles opening the ad detail screen directly when the app is launched or
/// resumed via a shared ad link, for Android App Links / iOS Universal Links
/// (https://ms.hmg.com/ad/1541) AND the custom-scheme fallback used by that
/// same web page when App Links verification isn't active
/// (mowatercustomer://ad/1541, mowaterprovider://ad/1541).
class AdDeepLinkService {
  static final AppLinks _appLinks = AppLinks();
  static StreamSubscription<Uri>? _subscription;

  /// Call once, after the app's first frame (so [navigatorKey] is attached to a Navigator).
  static Future<void> init() async {
    try {
      final Uri? initialUri = await _appLinks.getInitialLink();
      if (initialUri != null) {
        _handleUri(initialUri);
      }
    } catch (e) {
      log("AdDeepLinkService: failed to read initial link - $e");
    }

    _subscription?.cancel();
    _subscription = _appLinks.uriLinkStream.listen(
      _handleUri,
      onError: (Object e) => log("AdDeepLinkService: stream error - $e"),
    );
  }

  static void _handleUri(Uri uri) {
    log("AdDeepLinkService: received $uri");

    // https://ms.hmg.com/ad/1541 -> host="ms.hmg.com", pathSegments=["ad", "1541"]
    // mowatercustomer://ad/1541  -> host="ad" (Dart treats it as the authority), pathSegments=["1541"]
    int? adId;
    if (uri.scheme == 'https') {
      final segments = uri.pathSegments;
      if (segments.length >= 2 && segments[0] == 'ad') {
        adId = int.tryParse(segments[1]);
      }
    } else if (uri.host == 'ad' && uri.pathSegments.isNotEmpty) {
      adId = int.tryParse(uri.pathSegments.first);
    }

    if (adId == null) return;
    _openAd(adId);
  }

  static Future<void> _openAd(int adId) async {
    final context = navigatorKey.currentContext;
    if (context == null) return;

    Utils.showLoading(context);
    final adDetails = await context.read<AdVM>().getAdDetailsById(adId);
    Utils.hideLoading(context);

    if (adDetails == null) {
      Utils.showToast(LocaleKeys.somethingWrong.tr());
      return;
    }

    navigateWithName(context, AppRoutes.adsDetailView, arguments: adDetails);
  }
}