import 'package:flutter/material.dart';
import 'package:razorpay_flutter/razorpay_flutter.dart';
import 'package:marco/helpers/services/payment_service.dart';
import 'package:marco/helpers/services/tenant_service.dart';
import 'package:marco/helpers/services/app_logger.dart';
import 'package:get/get.dart';

class PaymentController with ChangeNotifier {
  Razorpay? _razorpay;
  final PaymentService _paymentService = PaymentService();
  final TenantService _tenantService = TenantService();

  bool isProcessing = false;

  // Pending values to use after payment verification
  String? _pendingTenantEnquireId;
  String? _pendingPlanId;

  /// ==============================
  /// START PAYMENT (Safe init)
  /// ==============================
  Future<void> startPayment({
    required double amount,
    required String description,
    required BuildContext context,
    String? tenantEnquireId,
    String? planId,
  }) async {
    try {
      isProcessing = true;
      notifyListeners();

      // Save pending ids for post-payment subscription call
      _pendingTenantEnquireId = tenantEnquireId;
      _pendingPlanId = planId;

      // Step 1: Create payment order
      final result = await _paymentService.createOrder(amount);
      logSafe("🧩 Raw response in PaymentController: $result");

      // Step 2: Validate result before accessing keys
      if (result == null) {
        _showError("Failed to create order. Server returned null response.");
        isProcessing = false;
        notifyListeners();
        return;
      }

      // Step 3: Handle both wrapped and unwrapped formats
      final data = result['data'] ?? result;
      final orderId = data?['orderId'];
      final key = data?['key'];

      if (orderId == null || key == null) {
        _showError("Invalid response from server. Missing orderId or key.");
        logSafe("💥 Invalid response structure: $result");
        isProcessing = false;
        notifyListeners();
        return;
      }

      // Step 4: Initialize Razorpay if needed
      _razorpay ??= Razorpay();
      _razorpay!.on(Razorpay.EVENT_PAYMENT_SUCCESS, _handlePaymentSuccess);
      _razorpay!.on(Razorpay.EVENT_PAYMENT_ERROR, _handlePaymentError);
      _razorpay!.on(Razorpay.EVENT_EXTERNAL_WALLET, _handleExternalWallet);

      // Step 5: Open Razorpay checkout
      final options = {
        'key': key,
        'amount': (amount * 100).toInt(), // Razorpay expects amount in paise
        'name': 'Marco',
        'description': description,
        'order_id': orderId,
        'prefill': {'contact': '9999999999', 'email': 'test@marco.com'},
      };

      logSafe("🟠 Opening Razorpay checkout with options: $options");
      _razorpay!.open(options);
    } catch (e, s) {
      _showError("Payment initialization failed. Please try again.");
      logSafe("💥 Exception in startPayment: $e\n$s");
    } finally {
      isProcessing = false;
      notifyListeners();
    }
  }

  /// ==============================
  /// EVENT HANDLERS
  /// ==============================
  void _handlePaymentSuccess(PaymentSuccessResponse response) async {
    logSafe("✅ Payment Success: ${response.paymentId}");
    isProcessing = true;
    notifyListeners();

    Map<String, dynamic>? verificationResult;

    try {
      logSafe("🟢 Verifying payment via backend...");
      verificationResult = await _paymentService
          .verifyPayment(
            paymentId: response.paymentId!,
            orderId: response.orderId!,
            signature: response.signature!,
          )
          .timeout(const Duration(seconds: 15));
      logSafe("🧩 Verification result: $verificationResult");
    } catch (e) {
      logSafe("⏱️ Verification timeout/error: $e", level: LogLevel.error);
    }

    isProcessing = false;
    notifyListeners();

    // Handle backend verification response properly
    if (verificationResult != null) {
      final isVerified = verificationResult['verified'] == true;
      final msg = verificationResult['message'] ?? '';

      if (isVerified) {
        // If we have pending tenant and plan IDs, call subscription API
        await _maybeSubscribeTenantAfterPayment(
          verificationResult: verificationResult,
          razorpayResponse: response,
        );

        _showDialog(
          title: "Payment Successful 🎉",
          message: msg.isNotEmpty ? msg : "Your payment was verified successfully.",
          success: true,
        );
      } else {
        _showDialog(
          title: "Verification Failed ❌",
          message: msg.isNotEmpty ? msg : "Payment completed but verification failed.",
          success: false,
        );
      }
    } else {
      _showDialog(
        title: "Verification Failed ❌",
        message: "Payment completed but backend verification returned null.",
        success: false,
      );
    }

    _cleanup();
  }

  Future<void> _maybeSubscribeTenantAfterPayment({
    required Map<String, dynamic> verificationResult,
    required PaymentSuccessResponse razorpayResponse,
  }) async {
    if (_pendingTenantEnquireId == null || _pendingPlanId == null) {
      logSafe("ℹ️ No pending tenant/plan id to subscribe.");
      return;
    }

    // Determine paymentDetailId — prefer backend value if provided
    final paymentDetailId = verificationResult['paymentDetailId'] ?? verificationResult['paymentId'] ?? razorpayResponse.paymentId;

    final subscribePayload = {
      "tenantEnquireId": _pendingTenantEnquireId,
      "paymentDetailId": paymentDetailId,
      "planId": _pendingPlanId,
    };

    logSafe("🟢 Subscribing tenant automatically: $subscribePayload");

    final subResp = await   _tenantService.subscribeTenant(subscribePayload);

    // Clear pending values immediately to avoid double-invoke
    _pendingTenantEnquireId = null;
    _pendingPlanId = null;

    if (subResp == null) {
      logSafe("❌ subscribeTenant returned null");
      _showDialog(
        title: "Subscription Failed",
        message: "Failed to call subscription API. Please contact support.",
        success: false,
      );
      return;
    }

    final data = subResp['data'] ?? subResp;
    // backend success flag might be in different places; check robustly
    final bool success = (data is Map && (data['success'] == true || subResp['success'] == true)) || (subResp['statusCode'] == 200);

    if (success) {
      _showDialog(
        title: "Subscription Active ✅",
        message: data['message'] ?? "Tenant subscribed successfully.",
        success: true,
      );
    } else {
      _showDialog(
        title: "Subscription Failed",
        message: data['message'] ?? "Subscription API did not confirm success.",
        success: false,
      );
    }
  }

  void _handlePaymentError(PaymentFailureResponse response) {
    logSafe("❌ Payment Failed: ${response.message}");
    isProcessing = false;
    notifyListeners();

    _showDialog(
      title: "Payment Failed ❌",
      message: "Reason: ${response.message ?? 'Unknown error'}",
      success: false,
    );

    _cleanup();
  }

  void _handleExternalWallet(ExternalWalletResponse response) {
    logSafe("ℹ️ External Wallet Used: ${response.walletName}");
  }

  /// ==============================
  /// CLEANUP / DISPOSE
  /// ==============================
  void _cleanup() {
    try {
      _razorpay?.clear();
    } catch (_) {}
    _razorpay = null;
    logSafe("🧹 Razorpay instance cleaned up.");
  }

  @override
  void dispose() {
    _cleanup();
    super.dispose();
  }

  void disposeController() => _cleanup();

  /// ==============================
  /// HELPER UI FUNCTIONS
  /// ==============================
  void _showDialog({
    required String title,
    required String message,
    required bool success,
  }) {
    if (Get.isDialogOpen == true) Get.back(); // Close any existing dialogs

    Get.defaultDialog(
      title: title,
      middleText: message,
      confirm: ElevatedButton(
        onPressed: () {
          Get.back(); // close dialog
          Get.snackbar(
            success ? "Payment Successful 🎉" : "Payment Failed ❌",
            success
                ? "Payment verified successfully!"
                : "Payment failed or could not be verified.",
            backgroundColor: success ? Colors.green : Colors.red,
            colorText: Colors.white,
            snackPosition: SnackPosition.BOTTOM,
          );
        },
        child: const Text("OK"),
      ),
    );
  }

  void _showError(String message) {
    if (Get.isDialogOpen == true) Get.back(); // Close any open dialog
    Get.snackbar(
      "Payment Error",
      message,
      backgroundColor: Colors.red,
      colorText: Colors.white,
      snackPosition: SnackPosition.BOTTOM,
    );
  }
}