import { useState, useEffect, useCallback } from 'react';
import AsyncStorage from '@react-native-async-storage/async-storage';
import { Transaction } from '../types';

const STORAGE_KEY = '@finance_transactions';

export const useTransactions = () => {
  const [transactions, setTransactions] = useState<Transaction[]>([]);
  const [loading, setLoading] = useState(true);

  const loadTransactions = useCallback(async () => {
    try {
      setLoading(true);
      const stored = await AsyncStorage.getItem(STORAGE_KEY);
      if (stored) {
        setTransactions(JSON.parse(stored));
      }
    } catch (error) {
      console.error('Error loading transactions:', error);
    } finally {
      setLoading(false);
    }
  }, []);

  useEffect(() => {
    loadTransactions();
  }, [loadTransactions]);

  const addTransaction = useCallback((transaction: Transaction) => {
    setTransactions((prev) => {
      const updated = [transaction, ...prev];
      AsyncStorage.setItem(STORAGE_KEY, JSON.stringify(updated));
      return updated;
    });
  }, []);

  const deleteTransaction = useCallback((id: string) => {
    setTransactions((prev) => {
      const updated = prev.filter((t) => t.id !== id);
      AsyncStorage.setItem(STORAGE_KEY, JSON.stringify(updated));
      return updated;
    });
  }, []);

  return {
    transactions,
    loading,
    addTransaction,
    deleteTransaction,
    refresh: loadTransactions,
  };
};