import 'dart:io';

void main() {
  List<Map<String, double>> incomes = [];
  List<Map<String, double>> expenses = [];

  while (true) {
    print('\nWelcome 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');

    stdout.write('\nEnter your choice: ');
    String? choice = stdin.readLineSync();

    switch (choice) {
      case '1':
        // إضافة دخل
        stdout.write('Enter income description: ');
        String? incomeDesc = stdin.readLineSync();

        stdout.write('Enter income amount: ');
        String? incomeAmountInput = stdin.readLineSync();
        double? incomeAmount = double.tryParse(incomeAmountInput ?? '');

        if (incomeAmount == null || incomeAmount < 0) {
          print('Invalid amount! Please enter a positive number.');
        } else {
          incomes.add({incomeDesc ?? 'Unknown': incomeAmount});
          print('Income added!');
        }
        break;

      case '2':
        // إضافة مصروف
        stdout.write('Enter expense description: ');
        String? expenseDesc = stdin.readLineSync();

        stdout.write('Enter expense amount: ');
        String? expenseAmountInput = stdin.readLineSync();
        double? expenseAmount = double.tryParse(expenseAmountInput ?? '');

        if (expenseAmount == null || expenseAmount < 0) {
          print('Invalid amount! Please enter a positive number.');
        } else {
          expenses.add({expenseDesc ?? 'Unknown': expenseAmount});
          print('Expense added!');
        }
        break;

      case '3':
        // عرض الملخص
        double totalIncome = 0;
        double totalExpense = 0;

        for (var inc in incomes) {
          totalIncome += inc.values.first;
        }

        for (var exp in expenses) {
          totalExpense += exp.values.first;
        }

        double netProfit = totalIncome - totalExpense;

        print('\nSummary:');
        print('Total income: \$${totalIncome.toStringAsFixed(2)}');
        print('Total expenses: \$${totalExpense.toStringAsFixed(2)}');

        if (netProfit > 0) {
          double tax = netProfit * 0.15;
          print('Net profit: \$${netProfit.toStringAsFixed(2)}');
          print('Tax to be paid: \$${tax.toStringAsFixed(2)}');
        } else if (netProfit < 0) {
          print('Net loss: \$${netProfit.abs().toStringAsFixed(2)}');
          print('No tax to be paid.');
        } else {
          print('Break-even: No profit or loss.');
        }
        break;

      case '4':
        print('Exiting the application. Goodbye!');
        return;

      default:
        print('Invalid choice! Please try again.');
    }
  }
}


القوائم (Lists):
	•	incomes لتخزين الدخل.
	•	expenses لتخزين المصروفات.
	•	المدخلات: المستخدم يكتب الوصف والمبلغ لكل دخل أو مصروف.
	•	الحسابات:
	•	totalIncome و totalExpense تجمع القيم.
	•	netProfit = totalIncome - totalExpense
	•	الضريبة:
يتم حساب 15٪ من الربح فقط إذا كان هناك ربح (باستخدام المشغل الثلاثي ? :).


import 'dart:io';

void main() {
  List<Map<String, double>> incomes = [];
  List<Map<String, double>> expenses = [];

  while (true) {
    print('\nWelcome 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');

    stdout.write('\nEnter your choice: ');
    String? choice = stdin.readLineSync();

    switch (choice) {
      case '1':
        // إضافة دخل
        stdout.write('Enter income description: ');
        String? incomeDesc = stdin.readLineSync();

        stdout.write('Enter income amount: ');
        String? incomeAmountInput = stdin.readLineSync();
        double? incomeAmount = double.tryParse(incomeAmountInput ?? '');

        if (incomeAmount == null || incomeAmount < 0) {
          print('Invalid amount! Please enter a positive number.');
        } else {
          incomes.add({incomeDesc ?? 'Unknown': incomeAmount});
          print('Income added!');
        }
        break;

      case '2':
        // إضافة مصروف
        stdout.write('Enter expense description: ');
        String? expenseDesc = stdin.readLineSync();

        stdout.write('Enter expense amount: ');
        String? expenseAmountInput = stdin.readLineSync();
        double? expenseAmount = double.tryParse(expenseAmountInput ?? '');

        if (expenseAmount == null || expenseAmount < 0) {
          print('Invalid amount! Please enter a positive number.');
        } else {
          expenses.add({expenseDesc ?? 'Unknown': expenseAmount});
          print('Expense added!');
        }
        break;

      case '3':
        // عرض الملخص
        double totalIncome = 0;
        double totalExpense = 0;

        print('\n========== Income Details ==========');
        if (incomes.isEmpty) {
          print('No income added yet.');
        } else {
          for (var inc in incomes) {
            print('- ${inc.keys.first}: \$${inc.values.first.toStringAsFixed(2)}');
            totalIncome += inc.values.first;
          }
        }

        print('\n========== Expense Details ==========');
        if (expenses.isEmpty) {
          print('No expenses added yet.');
        } else {
          for (var exp in expenses) {
            print('- ${exp.keys.first}: \$${exp.values.first.toStringAsFixed(2)}');
            totalExpense += exp.values.first;
          }
        }

        double netProfit = totalIncome - totalExpense;

        print('\n========== Summary ==========');
        print('Total income: \$${totalIncome.toStringAsFixed(2)}');
        print('Total expenses: \$${totalExpense.toStringAsFixed(2)}');

        if (netProfit > 0) {
          double tax = netProfit * 0.15;
          print('Net profit: \$${netProfit.toStringAsFixed(2)}');
          print('Tax to be paid: \$${tax.toStringAsFixed(2)}');
        } else if (netProfit < 0) {
          print('Net loss: \$${netProfit.abs().toStringAsFixed(2)}');
          print('No tax to be paid.');
        } else {
          print('Break-even: No profit or loss.');
        }
        break;

      case '4':
        print('Exiting the application. Goodbye!');
        return;

      default:
        print('Invalid choice! Please try again.');
    }
  }
}

الآن عند اختيار الخيار رقم 3 (View summary):

سيظهر الناتج بهذا الشكل


========== Income Details ==========
- Sales: $10000.00
- Investment: $2000.00

========== Expense Details ==========
- Rent: $3000.00
- Salaries: $1500.00

========== Summary ==========
Total income: $12000.00
Total expenses: $4500.00
Net profit: $7500.00
Tax to be paid: $1125.00