package org.openslx.dozmod.gui.wizard;

import java.awt.Color;
import java.awt.Dialog;

import javax.swing.Icon;
import javax.swing.JPanel;
import javax.swing.UIManager;

@SuppressWarnings("serial")
public abstract class WizardPage extends JPanel {

	private static final Color WARNING_COLOR = new Color(200, 100, 0);

	private final String title;

	private String description = null;

	private String message = null;

	private boolean isError = false;

	private boolean isComplete = false;

	protected final Wizard wizard;

	/**
	 * Whether the user is allowed to go back to this page once they clicked
	 * next.
	 */
	protected boolean canComeBack = true;

	public WizardPage(Wizard wizard, String title) {
		if (wizard == null)
			throw new NullPointerException("WizardPage needs a Wizard");
		this.wizard = wizard;
		this.title = title;
	}

	public String getTitle() {
		return this.title;
	}

	public String getMessage() {
		if (this.message != null)
			return this.message;
		return this.description;
	}

	private void updateHeader() {
		if (this.wizard != null)
			this.wizard.updateHeader(this);
	}

	protected Dialog getDialog() {
		return wizard;
	}

	public boolean isComplete() {
		return this.isComplete;
	}

	/*
	 * Feedback from the pages
	 */

	/**
	 * Called when the user wants to advance to the next page. You have the
	 * chance to run some sanity checks and return false if you want to prevent
	 * the user from switching the page, but in general it is recommended to
	 * disable the next button as long as there are errors in the current page.
	 * 
	 * @return true allows to flip the page, false cancels
	 */
	protected boolean wantNextOrFinish() {
		return isComplete;
	}

	/**
	 * Called when the page is being shown. This can be caused by three possible
	 * events:
	 * 1) The wizard opens and this is the fist page
	 * 2) The user clicked "Previous" and this is the previous page
	 * 3) The user clicked "Next" and this is the next page
	 */
	protected void onPageEnter() {
	}

	/**
	 * Called when the page is being hidden. This can be caused by three
	 * possible events:
	 * 1) The user clicked finish and this is the page currently displayed
	 * 2) The user clicked "Previous" and this is the current page
	 * 3) The user clicked "Next" and this is the current page
	 */
	protected void onPageLeave() {
	}

	/*
	 * Setters from derived classes
	 */

	protected void setPageComplete(boolean b) {
		if (isComplete == b)
			return;
		isComplete = b;
		if (wizard != null)
			wizard.updateButtons(this);
	}

	protected void setDescription(String description) {
		this.message = null;
		this.description = description;
		this.updateHeader();
	}

	protected void setErrorMessage(String message) {
		this.message = message;
		this.isError = true;
		this.updateHeader();
	}

	protected void setWarningMessage(String message) {
		this.message = message;
		this.isError = false;
		this.updateHeader();
	}

	protected Icon getMessageIcon() {
		if (message == null)
			return null;
		if (isError)
			return UIManager.getIcon("OptionPane.errorIcon");
		return UIManager.getIcon("OptionPane.warningIcon");
	}

	public Color getMessageColor() {
		if (message == null)
			return Color.BLACK;
		if (isError)
			return Color.RED;
		return WARNING_COLOR;
	}

}