import 'package:flutter/material.dart';

import 'package:collection/collection.dart';

import 'package:provider/provider.dart';

import 'package:pshared/models/payment/methods/data.dart';
import 'package:pshared/models/payment/methods/type.dart';
import 'package:pshared/models/payment/type.dart';
import 'package:pshared/models/recipient/recipient.dart';
import 'package:pshared/provider/recipient/pmethods.dart';
import 'package:pshared/provider/recipient/provider.dart';

import 'package:pweb/models/wallet.dart';
import 'package:pweb/providers/payment_flow.dart';
import 'package:pweb/pages/payment_methods/payment_page/body.dart';
import 'package:pweb/providers/wallets.dart';
import 'package:pweb/widgets/sidebar/destinations.dart';


class PaymentPage extends StatefulWidget {
  final ValueChanged<Recipient?>? onBack;
  final PaymentType? initialPaymentType;
  final PayoutDestination fallbackDestination;

  const PaymentPage({
    super.key,
    this.onBack,
    this.initialPaymentType,
    this.fallbackDestination = PayoutDestination.dashboard,
  });

  @override
  State<PaymentPage> createState() => _PaymentPageState();
}

class _PaymentPageState extends State<PaymentPage> {
  late final TextEditingController _searchController;
  late final FocusNode _searchFocusNode;
  late final PaymentFlowProvider _flowProvider;

  @override
  void initState() {
    super.initState();
    _searchController = TextEditingController();
    _searchFocusNode = FocusNode();
    _flowProvider = PaymentFlowProvider(
      initialType: widget.initialPaymentType ?? PaymentType.bankAccount,
    );

    WidgetsBinding.instance.addPostFrameCallback((_) => _initializePaymentPage());
  }

  @override
  void dispose() {
    _searchController.dispose();
    _searchFocusNode.dispose();
    _flowProvider.dispose();
    super.dispose();
  }

  void _initializePaymentPage() {
    final methodsProvider = context.read<PaymentMethodsProvider>();
    _handleWalletAutoSelection(methodsProvider);

    final recipient = context.read<RecipientsProvider>().currentObject;
    _syncFlowProvider(
      recipient: recipient,
      methodsProvider: methodsProvider,
      preferredType: widget.initialPaymentType,
    );
  }

  void _handleSearchChanged(String query) {
    context.read<RecipientsProvider>().setQuery(query);
  }

  void _handleRecipientSelected(Recipient recipient) {
    final recipientProvider = context.read<RecipientsProvider>();
    final methodsProvider = context.read<PaymentMethodsProvider>();

    recipientProvider.setCurrentObject(recipient.id);
    _flowProvider.reset(
      recipient: recipient,
      availableTypes: _availablePaymentTypes(recipient, methodsProvider),
      preferredType: widget.initialPaymentType,
    );
    _clearSearchField();
  }

  void _handleRecipientCleared() {
    final recipientProvider = context.read<RecipientsProvider>();
    final methodsProvider = context.read<PaymentMethodsProvider>();

    recipientProvider.setCurrentObject(null);
    _flowProvider.reset(
      recipient: null,
      availableTypes: _availablePaymentTypes(null, methodsProvider),
      preferredType: widget.initialPaymentType,
    );
    _clearSearchField();
  }

  void _clearSearchField() {
    _searchController.clear();
    _searchFocusNode.unfocus();
    context.read<RecipientsProvider>().setQuery('');
  }

  void _handleSendPayment() {
    // TODO: Handle Payment logic
    // AmplitudeService.paymentInitiated();
  }

  @override
  Widget build(BuildContext context) {
    final methodsProvider = context.watch<PaymentMethodsProvider>();
    final recipientProvider = context.watch<RecipientsProvider>();
    final recipient = recipientProvider.currentObject;
    final availableTypes = _availablePaymentTypes(recipient, methodsProvider);

    _syncFlowProvider(
      recipient: recipient,
      methodsProvider: methodsProvider,
      preferredType: recipient != null ? widget.initialPaymentType : null,
    );

    return ChangeNotifierProvider.value(
      value: _flowProvider,
      child: PaymentPageBody(
        onBack: widget.onBack,
        fallbackDestination: widget.fallbackDestination,
        recipient: recipient,
        recipientProvider: recipientProvider,
        methodsProvider: methodsProvider,
        availablePaymentTypes: availableTypes,
        searchController: _searchController,
        searchFocusNode: _searchFocusNode,
        onSearchChanged: _handleSearchChanged,
        onRecipientSelected: _handleRecipientSelected,
        onRecipientCleared: _handleRecipientCleared,
        onSend: _handleSendPayment,
      ),
    );
  }

  void _handleWalletAutoSelection(PaymentMethodsProvider methodsProvider) {
    final wallet = context.read<WalletsProvider>().selectedWallet;
    if (wallet == null) return;

    final matchingMethod = _getPaymentMethodForWallet(wallet, methodsProvider);
    if (matchingMethod != null) {
      methodsProvider.setCurrentObject(matchingMethod.id);
    }
  }

  void _syncFlowProvider({
    required Recipient? recipient,
    required PaymentMethodsProvider methodsProvider,
    PaymentType? preferredType,
  }) {
    _flowProvider.sync(
      recipient: recipient,
      availableTypes: _availablePaymentTypes(recipient, methodsProvider),
      preferredType: preferredType,
    );
  }

  MethodMap _availablePaymentTypes(
    Recipient? recipient,
    PaymentMethodsProvider methodsProvider,
  ) {
    if (recipient == null || !methodsProvider.isReady) return {};

    final methodsForRecipient = methodsProvider.methods.where(
      (method) => !method.isArchived && method.recipientRef == recipient.id,
    );

    return {
      for (final method in methodsForRecipient) method.type: method.data,
    };
  }

  PaymentMethod? _getPaymentMethodForWallet(
    Wallet wallet,
    PaymentMethodsProvider methodsProvider,
  ) {
    if (methodsProvider.methods.isEmpty) {
      return null;
    }

    return methodsProvider.methods.firstWhereOrNull(
      (method) =>
          method.type == PaymentType.wallet &&
          (method.description?.contains(wallet.walletUserID) ?? false),
    );
  }
}