// Budget Management CLI - Dart
// Save this file as question2.txt

import 'dart:io';

void main() {
  List<Map<String, dynamic>> incomeList = [];
  List<Map<String, dynamic>> expenseList = [];

  print('Welcome to Budget Management CLI');

  while (true) {
    print('\nMenu:');
    print('1. Add Income');
    print('2. Add Expense');
    print('3. View Summary');
    print('4. Exit');

    stdout.write('Enter choice (1-4): ');
    String? choice = stdin.readLineSync();
    if (choice == null) continue;

    if (choice == '4') {
      print('Exiting Budget Management CLI. Goodbye!');
      break;
    }

    if (choice == '1') {
      stdout.write('Enter income description: ');
      String? desc = stdin.readLineSync();
      if (desc == null || desc.trim().isEmpty) {
        print('Description cannot be empty.');
        continue;
      }
      stdout.write('Enter income amount (positive number): ');
      String? amtStr = stdin.readLineSync();
      double? amt = double.tryParse(amtStr ?? '');
      if (amt == null || amt < 0) {
        print('Invalid amount. Please enter a non-negative number.');
        continue;
      }
      incomeList.add({'desc': desc.trim(), 'amount': amt});
      print('Income added: ${desc.trim()} - \$${amt.toStringAsFixed(2)}');
    } else if (choice == '2') {
      stdout.write('Enter expense description: ');
      String? desc = stdin.readLineSync();
      if (desc == null || desc.trim().isEmpty) {
        print('Description cannot be empty.');
        continue;
      }
      stdout.write('Enter expense amount (positive number): ');
      String? amtStr = stdin.readLineSync();
      double? amt = double.tryParse(amtStr ?? '');
      if (amt == null || amt < 0) {
        print('Invalid amount. Please enter a non-negative number.');
        continue;
      }
      expenseList.add({'desc': desc.trim(), 'amount': amt});
      print('Expense added: ${desc.trim()} - \$${amt.toStringAsFixed(2)}');
    } else if (choice == '3') {
      double totalIncome = 0.0;
      double totalExpenses = 0.0;

      if (incomeList.isEmpty && expenseList.isEmpty) {
        print('No income or expense records yet.');
      } else {
        print('\n--- Income ---');
        for (var item in incomeList) {
          totalIncome += (item['amount'] as double);
          print('${item['desc']} : \$${(item['amount'] as double).toStringAsFixed(2)}');
        }

        print('\n--- Expenses ---');
        for (var item in expenseList) {
          totalExpenses += (item['amount'] as double);
          print('${item['desc']} : \$${(item['amount'] as double).toStringAsFixed(2)}');
        }

        double net = totalIncome - totalExpenses;
        if (net >= 0) {
          print('\nYour net profit is \$${net.toStringAsFixed(2)}');
        } else {
          print('\nYour net loss is \$${net.abs().toStringAsFixed(2)}');
        }

        double tax = net > 0 ? net * 0.15 : 0.0;
        if (tax > 0) {
          print('Tax to pay (15% of profit): \$${tax.toStringAsFixed(2)}');
        } else {
          print('No tax (no profit).');
        }
      }
    } else {
      print('Invalid choice. Please select 1-4.');
    }
  }
}