switch_case

import java.util.Scanner;

public class switch_case {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        // TODO: SECTION 1 - Basic Switch Statements

        // Example 1: Day of the week
        System.out.print("Enter a day number (1-7): ");
        int dayNumber = scanner.nextInt();

        String dayName;
        switch (dayNumber) {
            case 1:
                dayName = "Monday";
                break;
            case 2:
                dayName = "Tuesday";
                break;
            case 3:
                dayName = "Wednesday";
                break;
            case 4:
                dayName = "Thursday";
                break;
            case 5:
                dayName = "Friday";
                break;
            case 6:
                dayName = "Saturday";
                break;
            case 7:
                dayName = "Sunday";
                break;
            default:
                dayName = "Invalid day number! Please enter 1-7.";
        }
        System.out.println("Day: " + dayName);

        // Example 2: Simple calculator
        System.out.print("\nEnter first number: ");
        double num1 = scanner.nextDouble();
        System.out.print("Enter operator (+, -, *, /): ");
        char operator = scanner.next().charAt(0);
        System.out.print("Enter second number: ");
        double num2 = scanner.nextDouble();

        double result = 0.0;
        boolean validOperation = true;

        switch (operator) {
            case '+':
                result = num1 + num2;
                break;
            case '-':
                result = num1 - num2;
                break;
            case '*':
                result = num1 * num2;
                break;
            case '/':
                if (num2 != 0) {
                    result = num1 / num2;
                } else {
                    System.out.println("Error: Division by zero!");
                    validOperation = false;
                }
                break;
            default:
                System.out.println("Error: Invalid operator!");
                validOperation = false;
        }

        if (validOperation) {
            System.out.println("Result: " + num1 + " " + operator + " " + num2 + " = " + result);
        }

        // TODO: SECTION 2 - Switch with Multiple Labels

        // Example 1: Month categorization by season
        System.out.print("\nEnter a month number (1-12): ");
        int month = scanner.nextInt();

        String season;
        switch (month) {
            case 12, 1, 2:
                season = "Winter";
                break;
            case 3, 4, 5:
                season = "Spring";
                break;
            case 6, 7, 8:
                season = "Summer";
                break;
            case 9, 10, 11:
                season = "Fall";
                break;
            default:
                season = "Invalid month! Please enter 1-12.";
        }
        System.out.println("Season: " + season);

        // Example 2: Working days vs weekend
        System.out.print("Enter day number (1-7) to check if it's a working day: ");
        int day = scanner.nextInt();

        String dayType;
        switch (day) {
            case 1, 2, 3, 4, 5:
                dayType = "Working Day";
                break;
            case 6, 7:
                dayType = "Weekend";
                break;
            default:
                dayType = "Invalid day number!";
        }
        System.out.println(dayType);

        // TODO: SECTION 3 - Practical Applications
        System.out.println("\n=== Practical Applications ===\n");

        // Example 1: Restaurant Menu Ordering System
        System.out.println("--- Restaurant Menu ---");
        System.out.println("1. Burger - $8.99");
        System.out.println("2. Pizza - $12.99");
        System.out.println("3. Pasta - $10.99");
        System.out.println("4. Salad - $6.99");
        System.out.println("5. Steak - $18.99");
        System.out.print("Enter your choice (1-5): ");
        int menuChoice = scanner.nextInt();

        String itemName = "";
        double itemPrice = 0.0;
        int prepTime = 0; // in minutes

        switch (menuChoice) {
            case 1:
                itemName = "Burger";
                itemPrice = 8.99;
                prepTime = 10;
                break;
            case 2:
                itemName = "Pizza";
                itemPrice = 12.99;
                prepTime = 15;
                break;
            case 3:
                itemName = "Pasta";
                itemPrice = 10.99;
                prepTime = 12;
                break;
            case 4:
                itemName = "Salad";
                itemPrice = 6.99;
                prepTime = 5;
                break;
            case 5:
                itemName = "Steak";
                itemPrice = 18.99;
                prepTime = 20;
                break;
            default:
                System.out.println("Invalid choice! Please select 1-5.");
                scanner.close();
                return;
        }

        System.out.print("Enter quantity: ");
        int quantity = scanner.nextInt();
        double subtotal = itemPrice * quantity;
        double tax = subtotal * 0.08; // 8% tax
        double total = subtotal + tax;

        System.out.println("\n--- Order Summary ---");
        System.out.println("Item: " + itemName);
        System.out.println("Quantity: " + quantity);
        System.out.println("Price per item: $" + itemPrice);
        System.out.println("Subtotal: $" + subtotal);
        System.out.println("Tax (8%): $" + tax);
        System.out.println("Total: $" + total);
        System.out.println("Estimated prep time: " + (prepTime * quantity) + " minutes");

        // Example 2: University Grade System with Credits
        System.out.println("\n--- University Grade Calculator ---");
        System.out.print("Enter letter grade (A/B/C/D/F): ");
        char grade = scanner.next().charAt(0);
        System.out.print("Enter credit hours: ");
        int creditHours = scanner.nextInt();

        double gradePoints = 0.0;
        String gradeDescription = "";

        switch (grade) {
            case 'A':
                gradePoints = 4.0;
                gradeDescription = "Excellent";
                break;
            case 'B':
                gradePoints = 3.0;
                gradeDescription = "Good";
                break;
            case 'C':
                gradePoints = 2.0;
                gradeDescription = "Satisfactory";
                break;
            case 'D':
                gradePoints = 1.0;
                gradeDescription = "Poor";
                break;
            case 'F':
                gradePoints = 0.0;
                gradeDescription = "Fail";
                break;
            default:
                System.out.println("Invalid grade! Please enter A, B, C, D, or F.");
                scanner.close();
                return;
        }

        double qualityPoints = gradePoints * creditHours;

        System.out.println("\nGrade: " + grade + " (" + gradeDescription + ")");
        System.out.println("Grade Points: " + gradePoints);
        System.out.println("Credit Hours: " + creditHours);
        System.out.println("Quality Points: " + qualityPoints);

        // Example 3: ATM Machine Simulation
        System.out.println("\n--- ATM Machine ---");
        double accountBalance = 1000.00;
        System.out.println("Current Balance: $" + accountBalance);
        System.out.println("1. Deposit");
        System.out.println("2. Withdraw");
        System.out.println("3. Check Balance");
        System.out.println("4. Transfer");
        System.out.print("Select operation (1-4): ");
        int atmChoice = scanner.nextInt();

        String transactionMessage = "";
        boolean transactionSuccess = false;

        switch (atmChoice) {
            case 1: // Deposit
                System.out.print("Enter deposit amount: $");
                double depositAmount = scanner.nextDouble();
                if (depositAmount > 0 && depositAmount <= 10000) {
                    accountBalance += depositAmount;
                    transactionMessage = "Successfully deposited $" + depositAmount;
                    transactionSuccess = true;
                } else if (depositAmount <= 0) {
                    transactionMessage = "Invalid amount! Must be greater than $0.";
                } else {
                    transactionMessage = "Deposit limit exceeded! Maximum: $10,000.";
                }
                break;

            case 2: // Withdraw
                System.out.print("Enter withdrawal amount: $");
                double withdrawAmount = scanner.nextDouble();
                if (withdrawAmount > 0 && withdrawAmount <= accountBalance) {
                    if (withdrawAmount <= 500) {
                        accountBalance -= withdrawAmount;
                        transactionMessage = "Successfully withdrew $" + withdrawAmount;
                        transactionSuccess = true;
                    } else {
                        transactionMessage = "Daily withdrawal limit: $500.";
                    }
                } else if (withdrawAmount <= 0) {
                    transactionMessage = "Invalid amount!";
                } else {
                    transactionMessage = "Insufficient funds!";
                }
                break;

            case 3: // Check Balance
                transactionMessage = "Your current balance is $" + accountBalance;
                transactionSuccess = true;
                break;

            case 4: // Transfer
                System.out.print("Enter transfer amount: $");
                double transferAmount = scanner.nextDouble();
                System.out.print("Enter recipient account number: ");
                int recipientAccount = scanner.nextInt();

                if (transferAmount > 0 && transferAmount <= accountBalance) {
                    if (transferAmount <= 1000) {
                        accountBalance -= transferAmount;
                        transactionMessage = "Successfully transferred $" + transferAmount +
                                " to account #" + recipientAccount;
                        transactionSuccess = true;
                    } else {
                        transactionMessage = "Transfer limit exceeded! Maximum: $1,000.";
                    }
                } else if (transferAmount <= 0) {
                    transactionMessage = "Invalid transfer amount!";
                } else {
                    transactionMessage = "Insufficient funds for transfer!";
                }
                break;

            default:
                transactionMessage = "Invalid operation! Please select 1-4.";
        }

        System.out.println(transactionMessage);
        if (transactionSuccess && atmChoice != 3) {
            System.out.println("New Balance: $" + accountBalance);
        }

        scanner.close();
        System.out.println("\n=== Program Complete ===");
    }
}