import 'package:flutter/material.dart';

import 'package:provider/provider.dart';

import 'package:pshared/controllers/balance_mask/wallets.dart';
import 'package:pshared/provider/ledger.dart';
import 'package:pshared/models/payment/wallet.dart';

import 'package:pweb/pages/dashboard/buttons/balance/carousel.dart';
import 'package:pweb/pages/dashboard/buttons/balance/controller.dart';
import 'package:pweb/pages/dashboard/buttons/balance/balance_item.dart';

import 'package:pweb/generated/i18n/app_localizations.dart';


class BalanceWidget extends StatelessWidget {
  final ValueChanged<Wallet> onTopUp;

  const BalanceWidget({super.key, required this.onTopUp});

  @override
  Widget build(BuildContext context) => _BalanceWidgetBody(onTopUp: onTopUp);
}

class _BalanceWidgetBody extends StatefulWidget {
  final ValueChanged<Wallet> onTopUp;

  const _BalanceWidgetBody({required this.onTopUp});

  @override
  State<_BalanceWidgetBody> createState() => _BalanceWidgetBodyState();
}

class _BalanceWidgetBodyState extends State<_BalanceWidgetBody> {
  WalletsController? _walletsController;
  LedgerAccountsProvider? _ledgerProvider;
  CarouselIndexController? _carouselController;

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    final nextWallets = context.read<WalletsController>();
    final nextLedger = context.read<LedgerAccountsProvider>();
    final nextCarousel = context.read<CarouselIndexController>();

    if (!identical(_walletsController, nextWallets)) {
      _walletsController?.removeListener(_syncSelection);
      _walletsController = nextWallets;
      _walletsController?.addListener(_syncSelection);
    }

    if (!identical(_ledgerProvider, nextLedger)) {
      _ledgerProvider?.removeListener(_syncSelection);
      _ledgerProvider = nextLedger;
      _ledgerProvider?.addListener(_syncSelection);
    }

    if (!identical(_carouselController, nextCarousel)) {
      _carouselController?.removeListener(_syncSelection);
      _carouselController = nextCarousel;
      _carouselController?.addListener(_syncSelection);
    }

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

  @override
  void dispose() {
    _walletsController?.removeListener(_syncSelection);
    _ledgerProvider?.removeListener(_syncSelection);
    _carouselController?.removeListener(_syncSelection);
    super.dispose();
  }

  void _syncSelection() {
    final walletsController = _walletsController;
    final carousel = _carouselController;
    final ledgerProvider = _ledgerProvider;
    if (walletsController == null ||
        carousel == null ||
        ledgerProvider == null) {
      return;
    }

    final items = <BalanceItem>[
      ...walletsController.wallets.map(BalanceItem.wallet),
      ...ledgerProvider.accounts.map(BalanceItem.ledger),
      const BalanceItem.addAction(),
    ];
    if (items.isEmpty) return;

    final safeIndex = carousel.index.clamp(0, items.length - 1);
    if (safeIndex != carousel.index) {
      carousel.setIndex(safeIndex, items.length);
      return;
    }

    final current = items[safeIndex];
    if (!current.isWallet) return;
    final wallet = current.wallet!;
    if (walletsController.selectedWallet?.id != wallet.id) {
      walletsController.selectWallet(wallet);
    }
  }

  @override
  Widget build(BuildContext context) {
    final walletsController = context.watch<WalletsController>();
    final ledgerProvider = context.watch<LedgerAccountsProvider>();
    final carousel = context.watch<CarouselIndexController>();
    final loc = AppLocalizations.of(context)!;

    final wallets = walletsController.wallets;
    final accounts = ledgerProvider.accounts;
    final isLoading =
        walletsController.isLoading &&
        ledgerProvider.isLoading &&
        wallets.isEmpty &&
        accounts.isEmpty;

    if (isLoading) {
      return const Center(child: CircularProgressIndicator());
    }

    final items = [
      ...wallets.map(BalanceItem.wallet),
      ...accounts.map(BalanceItem.ledger),
      const BalanceItem.addAction(),
    ];

    if (items.isEmpty) {
      return const SizedBox.shrink();
    }

    final index = carousel.index.clamp(0, items.length - 1);

    final carouselWidget = BalanceCarousel(
      items: items,
      currentIndex: index,
      onIndexChanged: (i) {
        carousel.setIndex(i, items.length);
        final next = items[carousel.index];
        if (next.isWallet) {
          walletsController.selectWallet(next.wallet!);
        }
      },
      onTopUp: widget.onTopUp,
    );

    if (wallets.isEmpty && accounts.isEmpty) {
      return Column(
        mainAxisSize: MainAxisSize.min,
        children: [
          Center(child: Text(loc.noWalletsAvailable)),
          const SizedBox(height: 12),
          carouselWidget,
        ],
      );
    }

    return carouselWidget;
  }
}