package chapter01;

import javax.swing.*;

/**
 * This class is an implementation of PDUserInterface that uses JOptionPane to
 * display the menu of command choices.
 * 
 * @author Koffman & Wolfgang
 */

public class PDGUI implements PDUserInterface {

	/**
	 * A reference to the PhoneDirectory object to be processed. Globally
	 * available to the command-processing methods.
	 */
	private PhoneDirectory theDirectory = null;

	// Methods
	/**
	 * Method to display the command choices and process user commands. pre: The
	 * directory exists and has been loaded with data. post: The directory is
	 * updated based on user commands.
	 * 
	 * @param thePhoneDirectory
	 *            A reference to the PhoneDirectory to be processed
	 */
	public void processCommands(PhoneDirectory thePhoneDirectory) {

		String[] commands = { "Add/Change Entry", "Look Up Entry",
				"Remove Entry", "Save Directory", "Exit" };

		theDirectory = thePhoneDirectory;
		int choice;

		do {
			choice = JOptionPane.showOptionDialog(null, // No parent
					"Select a Command", // Prompt message
					"PhoneDirectory", // Window title
					JOptionPane.YES_NO_CANCEL_OPTION, // Option type
					JOptionPane.QUESTION_MESSAGE, // Message type
					null, // Icon
					commands, // List of commands
					commands[commands.length - 1]); // Default choice
			switch (choice) {
			case 0:
				doAddChangeEntry();
				break;
			case 1:
				doLookupEntry();
				break;
			case 2:
				doRemoveEntry();
				break;
			case 3:
			case 4:
				doSave();
				break;
			default: // Do nothing.
			}
		} while (choice != commands.length - 1);
		// System.exit(0);
	}

	/**
	 * Method to add or change an entry. pre: The directory exists and has been
	 * loaded with data. post: A new name is added, or the value for the name is
	 * changed, modified is set to true.
	 */
	private void doAddChangeEntry() {
		// Request the name
		String newName = JOptionPane.showInputDialog("Enter name");
		if (newName == null) {
			return; // Dialog was cancelled.
		}
		// Request the number
		String newNumber = JOptionPane.showInputDialog("Enter number");
		if (newNumber == null) {
			return; // Dialog was cancelled.
		}
		// Insert/change name-number
		String oldNumber = theDirectory.addOrChangeEntry(newName, newNumber);
		String message = null;
		if (oldNumber == null) { // New entry.
			message = newName + " was added to the directory"
					+ "\nNew number: " + newNumber;
		} else { // Changed entry.
			message = "Number for " + newName + " was changed "
					+ "\nOld number: " + oldNumber + "\nNew number: "
					+ newNumber;
		}
		// Display confirmation message.
		JOptionPane.showMessageDialog(null, message);
	}

	/**
	 * Method to look up an entry. pre: The directory has been loaded with data.
	 * post: No changes made to the directory.
	 */
	private void doLookupEntry() {
		// Request the name.
		String theName = JOptionPane.showInputDialog("Enter name");
		if (theName == null) {
			return; // Dialog was cancelled.
		}
		// Look up the name.
		String theNumber = theDirectory.lookupEntry(theName);
		String message = null;
		if (theNumber != null) { // Name was found.
			message = "The number for " + theName + " is " + theNumber;
		} else { // Name was not found.
			message = theName + " is not listed in the directory";
		}
		// Display the result.
		JOptionPane.showMessageDialog(null, message);
	}

	/**
	 * Method to remove an entry Pre: The directory has been loaded with data.
	 * Post: The requested name is removed, modifed is set true
	 */
	private void doRemoveEntry() {
		/** ** BEGIN EXERCISE *** */
		// Request the name
		String theName = JOptionPane.showInputDialog("Enter name");
		if (theName == null) {
			return; // Dialog was canceled
		}
		// Remove the entry
		String result = theDirectory.removeEntry(theName);
		// Display confirmation message
		if (result != null) {
			JOptionPane.showMessageDialog(null, theName
					+ " has been removed from" + " the directory");
		} else {
			JOptionPane.showMessageDialog(null, theName
					+ " is not in the directory");
		}
		/** ** END EXERCISE *** */
	}

	/**
	 * Method to save the directory to the data file. pre: The directory has
	 * been loaded with data. post: The current contents of the directory have
	 * been saved to the data file.
	 */
	private void doSave() {
		theDirectory.save();
	}

}