import 'package:collection/collection.dart';

import 'package:flutter/foundation.dart';

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


class WalletsController with ChangeNotifier {
  late WalletsProvider _wallets;

  // If you want per-org isolation, we reset when org changes.
  String? _orgRef;

  // Visibility is UI-only: store hidden wallet ids here.
  final Set<String> _hiddenWalletIds = <String>{};

  String? _selectedWalletId;

  bool get isLoading => _wallets.isLoading;

  Exception? get error => _wallets.error;

  /// Inject / update dependency (use ProxyProvider).
  void update(WalletsProvider wallets) {
    _wallets = wallets;

    final nextOrgRef = wallets.organizationId;
    final orgChanged = nextOrgRef != _orgRef;
    if (orgChanged) {
      _orgRef = nextOrgRef;
      _hiddenWalletIds.clear();
      _selectedWalletId = null;
    }

    // Prune hidden ids for wallets that no longer exist.
    final ids = wallets.wallets.map((w) => w.id).toSet();
    final beforeHiddenLen = _hiddenWalletIds.length;
    _hiddenWalletIds.removeWhere((id) => !ids.contains(id));

    // Ensure selection is valid.
    final beforeSelected = _selectedWalletId;
    _selectedWalletId = _resolveSelectedId(
      currentId: _selectedWalletId,
      wallets: wallets.wallets,
      hiddenIds: _hiddenWalletIds,
    );

    final selectionChanged = beforeSelected != _selectedWalletId;
    final hiddenChanged = beforeHiddenLen != _hiddenWalletIds.length;

    if (orgChanged || selectionChanged || hiddenChanged) {
      notifyListeners();
    }
  }

  List<Wallet> get wallets => _wallets.wallets;

  bool isHidden(String walletId) => _hiddenWalletIds.contains(walletId);

  List<Wallet> get visibleWallets =>
      wallets.where((w) => !_hiddenWalletIds.contains(w.id)).toList(growable: false);

  Wallet? get selectedWallet {
    final id = _selectedWalletId;
    if (id == null) return null;
    return wallets.firstWhereOrNull((w) => w.id == id);
  }

  String? get selectedWalletId => _selectedWalletId;

  void selectWallet(Wallet wallet) => selectWalletId(wallet.id);

  void selectWalletId(String walletId) {
    if (_selectedWalletId == walletId) return;

    // Allow selecting hidden wallet if you want; if not, block it:
    // if (isHidden(walletId)) return;

    _selectedWalletId = walletId;
    notifyListeners();
  }

  void toggleVisibility(String walletId) {
    final existed = _hiddenWalletIds.remove(walletId);
    if (!existed) _hiddenWalletIds.add(walletId);

    // If we hid the selected wallet, move selection to next visible.
    _selectedWalletId = _resolveSelectedId(
      currentId: _selectedWalletId,
      wallets: wallets,
      hiddenIds: _hiddenWalletIds,
    );

    notifyListeners();
  }

  void showAll() {
    if (_hiddenWalletIds.isEmpty) return;
    _hiddenWalletIds.clear();
    _selectedWalletId = _resolveSelectedId(
      currentId: _selectedWalletId,
      wallets: wallets,
      hiddenIds: _hiddenWalletIds,
    );
    notifyListeners();
  }

  String? _resolveSelectedId({
    required String? currentId,
    required List<Wallet> wallets,
    required Set<String> hiddenIds,
  }) {
    if (wallets.isEmpty) return null;

    // Keep current if exists and is not hidden.
    if (currentId != null) {
      final exists = wallets.any((w) => w.id == currentId);
      if (exists && !hiddenIds.contains(currentId)) return currentId;
    }

    // Pick first visible.
    final firstVisible = wallets.firstWhereOrNull((w) => !hiddenIds.contains(w.id));
    if (firstVisible != null) return firstVisible.id;

    // All hidden: fall back to first wallet id (or return null if you prefer).
    return wallets.first.id;
  }
}