import 'dart:io';

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

  print('Welcome to the Budget Management Application!');
  print('Please choose an option:');
  print('1. Add income');
  print('2. Add expense');
  print('3. View summary');
  print('4. Exit\n');

  bool running = true;
  while (running) {
    stdout.write('Enter your choice: ');
    String? choice = stdin.readLineSync();

    if (choice == '1') {
      stdout.write('Enter income description: ');
      String? description = stdin.readLineSync();

      if (description == null || description.trim().isEmpty) {
        print('Invalid description!\n');
      } else {
        stdout.write('Enter income amount: ');
        String? amountInput = stdin.readLineSync();

        if (amountInput != null && amountInput.trim().isNotEmpty) {
          try {
            double amount = double.parse(amountInput.trim());

            if (amount < 0) {
              print('Amount cannot be negative!\n');
            } else {
              incomeList.add({
                'description': description.trim(),
                'amount': amount,
              });
              print('Income added!\n');
            }
          } catch (e) {
            print('Invalid amount!\n');
          }
        } else {
          print('Invalid amount!\n');
        }
      }
    } else if (choice == '2') {
      stdout.write('Enter expense description: ');
      String? description = stdin.readLineSync();

      if (description == null || description.trim().isEmpty) {
        print('Invalid description!\n');
      } else {
        stdout.write('Enter expense amount: ');
        String? amountInput = stdin.readLineSync();

        if (amountInput != null && amountInput.trim().isNotEmpty) {
          try {
            double amount = double.parse(amountInput.trim());

            if (amount < 0) {
              print('Amount cannot be negative!\n');
            } else {
              expenseList.add({
                'description': description.trim(),
                'amount': amount,
              });
              print('Expense added!\n');
            }
          } catch (e) {
            print('Invalid amount!\n');
          }
        } else {
          print('Invalid amount!\n');
        }
      }
    } else if (choice == '3') {
      print('Summary:');

      double totalIncome = 0.0;
      for (var income in incomeList) {
        totalIncome += income['amount'];
      }

      double totalExpenses = 0.0;
      for (var expense in expenseList) {
        totalExpenses += expense['amount'];
      }

      print('Total income: \$${totalIncome.toStringAsFixed(0)}');
      print('Total expenses: \$${totalExpenses.toStringAsFixed(0)}');

      double netAmount = totalIncome - totalExpenses;

      if (netAmount > 0) {
        print('Net profit: \$${netAmount.toStringAsFixed(0)}');
        double tax = netAmount * 0.15;
        print('Tax to be paid: \$${tax.toStringAsFixed(0)}\n');
      } else if (netAmount < 0) {
        print('Net loss: \$${(-netAmount).toStringAsFixed(0)}\n');
      } else {
        print('Net profit: \$0\n');
      }
    } else if (choice == '4') {
      print('Exiting the application. Goodbye!');
      running = false;
    } else {
      print('Invalid choice.\n');
    }
  }
}