BudgetTime.java

import java.io.IOException;
import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * Class to take Budget input and store it
 *
 * @author Sam
 */

public class BudgetTime {

	/**
	 * Set recurring budget over a time period
	 *
	 * @throws IOException Handled in main along with other IO exceptions to reduce
	 *                     error handling code
	 */
	private void addBudget() throws IOException {
		int numberOfDays = timeInput(); // Gets time input from user and converts to days
		if (numberOfDays == 0) {
			return; // Quit if time input failed
		}

		System.out.println("Please enter a budget (£) for the selected time period");
		String amountString = App.userIn.readLine();
		double budgetAmount;
		if(!Validation.isDouble(amountString) || (budgetAmount = Double.parseDouble(amountString)) <= 0) {
			System.out.println("Invalid amount given\n\n");
			return;
		}

		if (amountString.contains(".")) {
			int decimalPos = amountString.indexOf('.');
			if ((amountString.length() - 1) - decimalPos > 2) {
				System.out.println("Invalid number, too precise\n\n");
				return;
			}
		}

		// Write SQL statement here then pass to method

		// Allow for option to select category
		System.out.println("Do you wish to set this budget for an existent category? (Y)es/(N)o");
		String option = App.userIn.readLine();
		String category = "Unknown";

		if(option.toLowerCase().equals("y")){
			displayCategories();
			System.out.println("Enter the name of the category: ");
			category = App.userIn.readLine();
			while (!exists(category)){
				System.out.println("This category does not exist, please enter an existent one: ");
				category = App.userIn.readLine();
			}
		}

		RetrieveAndStore.sqlExecute("INSERT INTO tblBudget (BudgetAmount, NumberOfDays, Category) VALUES ("
				+ budgetAmount + ", " + numberOfDays + ", '" + category + "')");
		System.out.println("Success a budget has been set for £" + budgetAmount + " every " + numberOfDays +
				" days in " + category + "!");
		RetrieveAndStore.rowNumberUpdater("tblBudget","BudgetID");
	}

	/**
	 * List all categories existent to let the user choose
	 */
	private void displayCategories(){
		ResultSet rs = RetrieveAndStore.readAllRecords("tblCategory");
		try{
			System.out.println("Please choose a category from the following: ");
			while (rs.next()){
				System.out.println(rs.getString("CategoryName"));
			}
		}catch (SQLException e){
			e.printStackTrace();
		}
	}

	/**
	 * Checks if the category typed by the user exists
	 * @param categoryName String representing category name
	 * @return true if category exists
	 * 			false otherwise
	 */
	private boolean exists(String categoryName){
		ResultSet rs = RetrieveAndStore.readAllRecords("tblCategory");
		try{
			while(rs.next()){
				if(rs.getString("CategoryName").equals(categoryName)) return true;
			}
			return false;
		} catch (SQLException e){
			e.printStackTrace();
			return false;
		}
	}

	/**
	 * Print the budgets from the database to the user
	 */
	private void printBudgets() {
		ResultSet rs = RetrieveAndStore.readAllRecords("tblBudget");
		try {
			while (rs.next()) // Loop through the resultset
			{
				// Store each budget record to print
				int id = rs.getInt("BudgetID");
				int budget = rs.getInt("BudgetAmount");
				int days = rs.getInt("NumberOfDays");
				String category = rs.getString("Category");

				// print the results
				System.out.format("%s. Budget amount = £%s, Number of days = %s, Category = %s\n", id, budget, days, category);
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	/**
	 * Delete a stored budget
	 *
	 * @throws IOException Handled in main along with other IO exceptions to reduce
	 *                     error handling code
	 */
	private void deleteBudget() throws IOException {
		printBudgets(); // Print all budgets to the console
		System.out.println("Please enter a record number to delete");
		String input = App.userIn.readLine();
		if (!Validation.isInteger(input)) {
			return;
		}
		if (!Validation.isRangeValid(1, RetrieveAndStore.maxID("tblBudget", "BudgetID"), Integer.parseInt(input))) {
			return;
		}
		RetrieveAndStore.sqlExecute("DELETE FROM tblBudget WHERE BudgetID = '" + input + "'"); // Call method to execute
																							   // deletion
		System.out.format("Record %s deleted successfully\n", input); // Tell the user record has been removed
	}

	/**
	 * Amend a stored budget
	 *
	 * @throws IOException Handled in main along with other IO exceptions to reduce
	 *                     error handling code
	 */
	private void amendBudget() throws IOException {
		printBudgets(); // Print all budgets to the console
		System.out.println("Please enter a record number to amend");
		String input = App.userIn.readLine();
		if (!Validation.isInteger(input)) { // Recordnumber input validated
			return;
		}
		int recordNumber = Integer.parseInt(input);
		if (!Validation.isRangeValid(1, RetrieveAndStore.maxID("tblBudget", "BudgetID"), recordNumber)) {
			return;
		}
		System.out.println("Would you like to change:\n 1.budget\n 2.time frame?\n 3.category"); // Find out what the user wants to
																					// amend
		input = App.userIn.readLine();
		switch (input) {
		case "1": // Switch statement to deal with both cases of amendments
			System.out.println("Please enter an amount (£)");
			String amountString = App.userIn.readLine();
			double amount;
			if(!Validation.isDouble(amountString) || (amount = Double.parseDouble(amountString)) <= 0) {
				System.out.println("Invalid amount given\n\n");
				return;
			}

			if (amountString.contains(".")) {
				int decimalPos = amountString.indexOf('.');
				if ((amountString.length() - 1) - decimalPos > 2) {
					System.out.println("Invalid number, too precise\n\n");
					return;
				}
			}
			RetrieveAndStore
					.sqlExecute("UPDATE tblBudget SET BudgetAmount = " + amount + " WHERE BudgetID = " + recordNumber);
			break;
		case "2":
			int days = timeInput();
			RetrieveAndStore
					.sqlExecute("UPDATE tblBudget SET NumberOfDays = " + days + " WHERE BudgetID = " + recordNumber);
			break;
		case "3":
			displayCategories();
			String category = App.userIn.readLine();
			while (!exists(category)){
				System.out.println("Category does not exist, please enter an existent one.");
				category = App.userIn.readLine();
			}
			RetrieveAndStore
					.sqlExecute("UPDATE tblBudget SET Category = '" + category + "' WHERE BudgetID = " + recordNumber);
			break;
		default:
			System.out.println("Not an option, try again"); // Filters out invalid input
		}
	}

	/**
	 * Take input of time period and convert to days
	 *
	 * @return time period for goal in days
	 * @throws IOException Handled in main along with other IO exceptions to reduce
	 *                     error handling code
	 */
	private int timeInput() throws IOException {
		int timePeriod = 0;
		int lengthTime = 0;
		String input; // To hold input from user via console

		System.out.println("Would you like to input your budget in: \n 1.Days \n 2.Calendar Months \n 3.Years");
		input = App.userIn.readLine();
		if (!Validation.isInteger(input)) {
			return 0;
		}
		timePeriod = Integer.parseInt(input);
		if (!Validation.isRangeValid(1, 3, timePeriod)) {
			return 0;
		}

		System.out.println("Please enter the number of days/months/years you would like this goal for");
		input = App.userIn.readLine();
		if (!Validation.isInteger(input)) {
			return 0;
		}
		lengthTime = Integer.parseInt(input);

		// if statement to normalise input to number of days ready to be stored
		if (timePeriod == 1) {
			return lengthTime;
		} else if (timePeriod == 2) {
			lengthTime *= 28;
			return lengthTime;
		} else if (timePeriod == 3) {
			lengthTime *= 365;
			return lengthTime;
		}
		return 0;
	}

	/**
	 * Called from the main program to give user budget options Handles all
	 * IOExceptions thrown at other points in class
	 *
	 * @throws IOException
	 */
	public void mainMenu() throws IOException {
		boolean loop = true;
		while (loop) {
			System.out.println(
					"Would you like to:\n 1. Add a budget\n 2. Remove a budget\n 3. Amend a budget\n 4. View all budgets\n 5. Quit to main menu");
			String input = App.userIn.readLine();

			switch (input) { // Use user input to decide which action to complete
			case "1":
				addBudget();
				break;
			case "2":
				deleteBudget();
				break;
			case "3":
				amendBudget();
				break;
			case "4":
				printBudgets();
				break;
			case "5":
				loop = false;
			default: // Filter out invalid inputs
				System.out.println("Not an option, try again");
			}
		}

	}

}