import 'dart:html' as html;

import 'package:flutter/material.dart';
import 'package:manager_api_new/api.dart';
import 'package:manager_app/Components/common_loader.dart';
import 'package:manager_app/Components/message_notification.dart';
import 'package:manager_app/Components/rounded_button.dart';
import 'package:manager_app/Models/managerContext.dart';
import 'package:manager_app/app_context.dart';
import 'package:manager_app/constants.dart';
import 'package:manager_app/l10n/app_localizations.dart';
import 'package:provider/provider.dart';

/// Subscription screen for the Essentiel plan only — Pro/Premium/Enterprise
/// remain fully manual (contact commercial), so they have no self-service
/// screen here. Shows trial status + what's included, and lets the user
/// convert to a paid subscription via a Stripe-hosted Checkout Session.
///
/// The "Add-ons" section below is intentionally a placeholder for now — it's
/// the future home of the paid AI request quota add-on, not implemented yet.
class SubscriptionScreen extends StatefulWidget {
  const SubscriptionScreen({Key? key}) : super(key: key);

  @override
  _SubscriptionScreenState createState() => _SubscriptionScreenState();
}

class _SubscriptionScreenState extends State<SubscriptionScreen> {
  bool isRedirecting = false;

  List<String> _includedFeatures(AppLocalizations l) => [
    l.subscriptionFeatureWebApp,
    l.subscriptionFeatureUnlimited,
    l.subscriptionFeatureMultilang,
    l.subscriptionFeatureBranding,
  ];

  Future<void> _startCheckout(ManagerAppContext ctx) async {
    setState(() => isRedirecting = true);
    try {
      final url = await ctx.clientAPI!.onboardingApi!.onboardingCreateCheckoutSession();
      html.window.open(url, '_blank');
    } catch (e) {
      showNotification(kError, kWhite, AppLocalizations.of(context)!.subscriptionCheckoutError, context, null);
    } finally {
      if (mounted) setState(() => isRedirecting = false);
    }
  }

  /// Portail Stripe : changer de carte, relire ses factures, résilier. Stripe héberge la page.
  ///
  /// ⚠️ Le 409 n'est pas une erreur à afficher comme telle : il dit que l'instance n'a pas de
  /// client Stripe — le cas de **tous les clients venus de la migration Mongo**, qui n'ont
  /// jamais souscrit en ligne. Leur montrer « réessayez plus tard » les ferait attendre
  /// quelque chose qui n'arrivera pas ; le message dit que leur facturation passe par nous.
  Future<void> _openBillingPortal(ManagerAppContext ctx) async {
    setState(() => isRedirecting = true);
    try {
      final url = await ctx.clientAPI!.onboardingApi!.onboardingCreateBillingPortalSession();
      html.window.open(url, '_blank');
    } on ApiException catch (e) {
      if (!mounted) return;
      final l = AppLocalizations.of(context)!;
      final message = e.code == 409 ? l.subscriptionPortalNoCustomer : l.subscriptionPortalError;
      showNotification(kError, kWhite, message, context, null);
    } catch (e) {
      if (mounted) {
        showNotification(kError, kWhite, AppLocalizations.of(context)!.subscriptionPortalError, context, null);
      }
    } finally {
      if (mounted) setState(() => isRedirecting = false);
    }
  }

  String _formatDate(DateTime date) {
    final d = date.toLocal();
    return "${d.day.toString().padLeft(2, '0')}/${d.month.toString().padLeft(2, '0')}/${d.year}";
  }

  @override
  Widget build(BuildContext context) {
    final l = AppLocalizations.of(context)!;
    final managerCtx = Provider.of<AppContext>(context).getContext() as ManagerAppContext;
    final instance = managerCtx.instanceDTO;
    final isTrialActive = instance?.isTrialActive == true;
    final trialEndsAt = instance?.trialEndsAt;

    return SingleChildScrollView(
      padding: const EdgeInsets.all(8.0),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(l.subscriptionTitle, style: TextStyle(fontSize: 24, fontWeight: FontWeight.w600, color: kPrimaryColor)),
          const SizedBox(height: 16),
          Card(
            elevation: 0,
            color: isTrialActive ? kPrimaryColor.withValues(alpha: 0.06) : kSuccess.withValues(alpha: 0.08),
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(12),
              side: BorderSide(color: (isTrialActive ? kPrimaryColor : kSuccess).withValues(alpha: 0.25)),
            ),
            child: Padding(
              padding: const EdgeInsets.all(20),
              child: Row(
                children: [
                  Icon(
                    isTrialActive ? Icons.hourglass_top_rounded : Icons.check_circle_outline,
                    color: isTrialActive ? kPrimaryColor : kSuccess,
                    size: 32,
                  ),
                  const SizedBox(width: 16),
                  Expanded(
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Text(
                          isTrialActive ? l.subscriptionTrialActive : l.subscriptionPlanActive,
                          style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w600),
                        ),
                        const SizedBox(height: 4),
                        Text(
                          isTrialActive
                              ? (trialEndsAt != null
                                  ? l.subscriptionTrialEndsAt(_formatDate(trialEndsAt))
                                  : l.subscriptionTrialNoDate)
                              : l.subscriptionPlanActiveDesc,
                          style: TextStyle(fontSize: 13, color: Colors.grey[700]),
                        ),
                      ],
                    ),
                  ),
                ],
              ),
            ),
          ),
          const SizedBox(height: 24),
          Text(l.subscriptionIncludedTitle, style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w600)),
          const SizedBox(height: 12),
          ..._includedFeatures(l).map((feature) => Padding(
                padding: const EdgeInsets.only(bottom: 8),
                child: Row(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Icon(Icons.check, color: kSuccess, size: 18),
                    const SizedBox(width: 8),
                    Expanded(child: Text(feature, style: const TextStyle(fontSize: 14))),
                  ],
                ),
              )),
          const SizedBox(height: 16),
          if (isRedirecting)
            const CommonLoader(iconSize: 32)
          else if (isTrialActive)
            RoundedButton(
              text: l.subscriptionUpgradeBtn,
              fontSize: 15,
              vertical: 14,
              horizontal: 24,
              press: () => _startCheckout(managerCtx),
            )
          else ...[
            // Hors essai, l'abonnement est en cours : ce qu'on peut encore vouloir faire ici,
            // c'est corriger une carte ou relire une facture — pas souscrire une seconde fois.
            Text(l.subscriptionManageDesc, style: TextStyle(fontSize: 13, color: Colors.grey[700])),
            const SizedBox(height: 12),
            RoundedButton(
              text: l.subscriptionManageBtn,
              fontSize: 15,
              vertical: 14,
              horizontal: 24,
              press: () => _openBillingPortal(managerCtx),
            ),
          ],
          const SizedBox(height: 32),
          Text(l.subscriptionAddonsTitle, style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w600)),
          const SizedBox(height: 8),
          Text(
            l.subscriptionAddonsComingSoon,
            style: TextStyle(fontSize: 13, color: Colors.grey[600]),
          ),
        ],
      ),
    );
  }
}