import 'dart:async';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../data/repository.dart';
import '../data/models.dart';

final apiRepositoryProvider = Provider((ref) => ApiRepository());

class CategoryNotifier extends AsyncNotifier<List<Category>> {
  @override
  FutureOr<List<Category>> build() {
    return ref.watch(apiRepositoryProvider).getCategories();
  }

  Future<void> addCategory(String name, String? iconName) async {
    final newCategory = await ref.read(apiRepositoryProvider).addCategory(Category(id: 0, name: name, iconName: iconName));
    if (state.value != null) {
      state = AsyncValue.data([...state.value!, newCategory]);
    }
  }
}

final categoryProvider = AsyncNotifierProvider<CategoryNotifier, List<Category>>(() => CategoryNotifier());


class TransactionNotifier extends AsyncNotifier<List<Transaction>> {
  @override
  FutureOr<List<Transaction>> build() {
    return ref.watch(apiRepositoryProvider).getTransactions();
  }

  Future<void> addTransaction(Transaction transaction, {List<Map<String, String>>? base64Attachments}) async {
    final newTransaction = await ref.read(apiRepositoryProvider).addTransaction(transaction);
    
    // Upload attachments if any
    if (base64Attachments != null && base64Attachments.isNotEmpty) {
      for (var attachment in base64Attachments) {
        await ref.read(apiRepositoryProvider).addAttachment(
          newTransaction.id, 
          attachment['fileName']!, 
          attachment['contentType']!, 
          attachment['base64Content']!
        );
      }
    }

    if (state.value != null) {
      // Re-fetch transactions to get the fully populated transaction with attachments from backend
      ref.invalidateSelf();
    }
  }

  Future<void> updateTransaction(Transaction transaction, {List<Map<String, String>>? base64Attachments, List<int>? deletedAttachmentIds}) async {
    final updatedTransaction = await ref.read(apiRepositoryProvider).updateTransaction(transaction);
    
    if (base64Attachments != null && base64Attachments.isNotEmpty) {
      for (var attachment in base64Attachments) {
        await ref.read(apiRepositoryProvider).addAttachment(
          updatedTransaction.id, 
          attachment['fileName']!, 
          attachment['contentType']!, 
          attachment['base64Content']!
        );
      }
    }
    
    if (deletedAttachmentIds != null && deletedAttachmentIds.isNotEmpty) {
      for (var id in deletedAttachmentIds) {
        await ref.read(apiRepositoryProvider).deleteAttachment(id);
      }
    }

    ref.invalidate(walletProvider);
    ref.invalidateSelf();
  }

  Future<void> deleteTransaction(int id) async {
    await ref.read(apiRepositoryProvider).deleteTransaction(id);
    ref.invalidate(walletProvider);
    if (state.value != null) {
      state = AsyncValue.data(state.value!.where((t) => t.id != id).toList());
    }
  }

  Future<void> closeInvestment(int id, double maturityAmount, DateTime closingDate, int toWalletId) async {
    final updatedTransaction = await ref.read(apiRepositoryProvider).closeInvestment(id, maturityAmount, closingDate, toWalletId);
    if (state.value != null) {
      final updatedList = state.value!.map((t) => t.id == updatedTransaction.id ? updatedTransaction : t).toList();
      state = AsyncValue.data(updatedList);
    }
  }
}

final transactionProvider = AsyncNotifierProvider<TransactionNotifier, List<Transaction>>(() => TransactionNotifier());

class BudgetNotifier extends AsyncNotifier<List<Budget>> {
  @override
  FutureOr<List<Budget>> build() {
    return ref.watch(apiRepositoryProvider).getBudgets();
  }

  Future<void> addOrUpdateBudget(Budget budget) async {
    final updatedBudget = await ref.read(apiRepositoryProvider).addOrUpdateBudget(budget);
    if (state.value != null) {
      final list = List<Budget>.from(state.value!);
      final index = list.indexWhere((b) => 
        (b.categoryId != null && b.categoryId == budget.categoryId) || 
        (b.walletId != null && b.walletId == budget.walletId)
      );
      if (index >= 0) {
        list[index] = updatedBudget;
      } else {
        list.add(updatedBudget);
      }
      state = AsyncValue.data(list);
    }
  }
}

final budgetProvider = AsyncNotifierProvider<BudgetNotifier, List<Budget>>(() => BudgetNotifier());

class RecurringTransactionNotifier extends AsyncNotifier<List<RecurringTransaction>> {
  @override
  FutureOr<List<RecurringTransaction>> build() {
    return ref.watch(apiRepositoryProvider).getRecurringTransactions();
  }

  Future<void> addRecurringTransaction(RecurringTransaction rt) async {
    final newRt = await ref.read(apiRepositoryProvider).addRecurringTransaction(rt);
    if (state.value != null) {
      state = AsyncValue.data([newRt, ...state.value!]);
    }
  }
}

final recurringTransactionProvider = AsyncNotifierProvider<RecurringTransactionNotifier, List<RecurringTransaction>>(() => RecurringTransactionNotifier());

class WalletNotifier extends AsyncNotifier<List<Wallet>> {
  @override
  FutureOr<List<Wallet>> build() async {
    final wallets = await ref.watch(apiRepositoryProvider).getWallets();
    wallets.sort((a, b) => a.name.toLowerCase().compareTo(b.name.toLowerCase()));
    return wallets;
  }

  Future<Wallet> createWallet({
    required String name,
    String nature = 'CASH',
    double initialBalance = 0.0,
    DateTime? initialBalanceDate,
    String currency = 'INR',
    String? icon,
    String? color,
    String? subNature,
    double? creditLimit,
    double? fixedAmount,
    String? paymentCycle,
    int? cycleDate,
  }) async {
    final newWallet = await ref.read(apiRepositoryProvider).createWallet(
      name: name,
      nature: nature,
      initialBalance: initialBalance,
      initialBalanceDate: initialBalanceDate != null ? "${initialBalanceDate.year}-${initialBalanceDate.month.toString().padLeft(2, '0')}-${initialBalanceDate.day.toString().padLeft(2, '0')}" : null,
      currency: currency,
      icon: icon,
      color: color,
      subNature: subNature,
      creditLimit: creditLimit,
      fixedAmount: fixedAmount,
      paymentCycle: paymentCycle,
      cycleDate: cycleDate,
    );
    if (state.value != null) {
      final updated = [...state.value!, newWallet];
      updated.sort((a, b) => a.name.toLowerCase().compareTo(b.name.toLowerCase()));
      state = AsyncValue.data(updated);
    }
    return newWallet;
  }

  Future<void> inviteUser(int walletId, String email) async {
    await ref.read(apiRepositoryProvider).inviteUserToWallet(walletId, email);
  }

  Future<void> editWallet(int id, {String? name, String? nature, String? icon, String? color, double? initialBalance, DateTime? initialBalanceDate, String? subNature, double? creditLimit, double? fixedAmount, String? paymentCycle, int? cycleDate}) async {
    final updated = await ref.read(apiRepositoryProvider).editWallet(
      id: id,
      name: name,
      nature: nature,
      icon: icon,
      color: color,
      initialBalance: initialBalance,
      initialBalanceDate: initialBalanceDate != null ? "${initialBalanceDate.year}-${initialBalanceDate.month.toString().padLeft(2, '0')}-${initialBalanceDate.day.toString().padLeft(2, '0')}" : null,
      subNature: subNature,
      creditLimit: creditLimit,
      fixedAmount: fixedAmount,
      paymentCycle: paymentCycle,
      cycleDate: cycleDate,
    );
    if (state.value != null) {
      final updatedList = state.value!.map((w) => w.id == id ? updated : w).toList();
      updatedList.sort((a, b) => a.name.toLowerCase().compareTo(b.name.toLowerCase()));
      state = AsyncValue.data(updatedList);
    }
  }

  Future<void> deleteWallet(int id) async {
    await ref.read(apiRepositoryProvider).deleteWallet(id);
    if (state.value != null) {
      state = AsyncValue.data(
        state.value!.where((w) => w.id != id).toList(),
      );
    }
  }
}

class InvitationNotifier extends AsyncNotifier<List<WalletInvitation>> {
  @override
  Future<List<WalletInvitation>> build() async {
    return ref.read(apiRepositoryProvider).getInvitations();
  }

  Future<void> acceptInvitation(int invitationId) async {
    await ref.read(apiRepositoryProvider).acceptInvitation(invitationId);
    state = AsyncValue.data(state.value?.where((inv) => inv.id != invitationId).toList() ?? []);
    ref.invalidate(walletProvider); // Refresh wallets
  }

  Future<void> rejectInvitation(int invitationId) async {
    await ref.read(apiRepositoryProvider).rejectInvitation(invitationId);
    state = AsyncValue.data(state.value?.where((inv) => inv.id != invitationId).toList() ?? []);
  }
}

final walletProvider = AsyncNotifierProvider<WalletNotifier, List<Wallet>>(() => WalletNotifier());
final invitationProvider = AsyncNotifierProvider<InvitationNotifier, List<WalletInvitation>>(() => InvitationNotifier());