/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.widgets;


import org.eclipse.swt.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.gtk.*;

/**
 * Instances of this class are used used to inform or warn the user.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>ICON_ERROR, ICON_INFORMATION, ICON_QUESTION, ICON_WARNING, ICON_WORKING</dd>
 * <dd>OK, OK | CANCEL</dd>
 * <dd>YES | NO, YES | NO | CANCEL</dd>
 * <dd>RETRY | CANCEL</dd>
 * <dd>ABORT | RETRY | IGNORE</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * Note: Only one of the styles ICON_ERROR, ICON_INFORMATION, ICON_QUESTION,
 * ICON_WARNING and ICON_WORKING may be specified.
 * </p><p>
 * IMPORTANT: This class is intended to be subclassed <em>only</em>
 * within the SWT implementation.
 * </p>
 */
public class MessageBox extends Dialog {

	String message = "";
	int /*long*/ handle;
/**
 * Constructs a new instance of this class given only its parent.
 *
 * @param parent a shell which will be the parent of the new instance
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
 *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
 * </ul>
 */
public MessageBox (Shell parent) {
	this (parent, SWT.OK | SWT.ICON_INFORMATION | SWT.APPLICATION_MODAL);
}

/**
 * Constructs a new instance of this class given its parent
 * and a style value describing its behavior and appearance.
 * <p>
 * The style value is either one of the style constants defined in
 * class <code>SWT</code> which is applicable to instances of this
 * class, or must be built by <em>bitwise OR</em>'ing together 
 * (that is, using the <code>int</code> "|" operator) two or more
 * of those <code>SWT</code> style constants. The class description
 * lists the style constants that are applicable to the class.
 * Style bits are also inherited from superclasses.
 *
 * @param parent a shell which will be the parent of the new instance
 * @param style the style of dialog to construct
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
 *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
 * </ul>
 */
public MessageBox (Shell parent, int style) {
	super(parent, checkStyle(style));
	checkSubclass ();
}

/**
 * Returns the dialog's message, which is a description of
 * the purpose for which it was opened. This message will be
 * visible on the dialog while it is open.
 *
 * @return the message
 */
public String getMessage () {
	return message;
}

/**
 * Sets the dialog's message, which is a description of
 * the purpose for which it was opened. This message will be
 * visible on the dialog while it is open.
 *
 * @param string the message
 * 
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the string is null</li>
 * </ul>
 */
public void setMessage (String string) {
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	message = string;
}

/**
 * Makes the dialog visible and brings it to the front
 * of the display.
 *
 * @return the ID of the button that was selected to dismiss the
 *         message box (e.g. SWT.OK, SWT.CANCEL, etc...)
 *
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the dialog has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the dialog</li>
 * </ul>
 */
public int open () {
	int /*long*/ parentHandle = (parent != null) ? parent.topHandle() : 0;
	int dialogFlags = OS.GTK_DIALOG_DESTROY_WITH_PARENT;
	if ((style & (SWT.PRIMARY_MODAL | SWT.APPLICATION_MODAL | SWT.SYSTEM_MODAL)) != 0) {
		dialogFlags |= OS.GTK_DIALOG_MODAL;
	}
	int messageType = OS.GTK_MESSAGE_INFO;
	if ((style & (SWT.ICON_WARNING)) != 0)  messageType = OS.GTK_MESSAGE_WARNING;
	if ((style & (SWT.ICON_QUESTION)) != 0) messageType = OS.GTK_MESSAGE_QUESTION;
	if ((style & (SWT.ICON_ERROR)) != 0)    messageType = OS.GTK_MESSAGE_ERROR;
	
	byte [] buffer = Converter.wcsToMbcs (null, fixPercent (message), true);
	handle = OS.gtk_message_dialog_new(parentHandle, dialogFlags, messageType, 0, buffer);
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	createButtons();
	buffer = Converter.wcsToMbcs(null, title, true);
	OS.gtk_window_set_title(handle,buffer);
	int result = OS.gtk_dialog_run(handle);
	OS.gtk_widget_destroy(handle);
	return result;
}

private void createButtons() {
	if ((style & SWT.OK) != 0) OS.gtk_dialog_add_button(handle, Converter.wcsToMbcs (null, "gtk-ok", true), SWT.OK);
	if ((style & SWT.CANCEL) != 0) OS.gtk_dialog_add_button(handle, Converter.wcsToMbcs (null, "gtk-cancel", true), SWT.CANCEL);
	if ((style & SWT.YES) != 0) OS.gtk_dialog_add_button(handle, Converter.wcsToMbcs (null, "gtk-yes", true), SWT.YES);
	if ((style & SWT.NO) != 0) OS.gtk_dialog_add_button(handle, Converter.wcsToMbcs (null, "gtk-no", true), SWT.NO);
	if ((style & SWT.ABORT) != 0) OS.gtk_dialog_add_button(handle, Converter.wcsToMbcs (null, SWT.getMessage("SWT_Abort"), true), SWT.ABORT);
	if ((style & SWT.RETRY) != 0) OS.gtk_dialog_add_button(handle, Converter.wcsToMbcs (null, SWT.getMessage("SWT_Retry"), true), SWT.RETRY);
	if ((style & SWT.IGNORE) != 0) OS.gtk_dialog_add_button(handle, Converter.wcsToMbcs (null, SWT.getMessage("SWT_Ignore"), true), SWT.IGNORE);
}

private static int checkStyle (int style) {
	int mask = (SWT.YES | SWT.NO | SWT.OK | SWT.CANCEL | SWT.ABORT | SWT.RETRY | SWT.IGNORE);
	int bits = style & mask;
	if (bits == SWT.OK || bits == SWT.CANCEL || bits == (SWT.OK | SWT.CANCEL)) return style;
	if (bits == SWT.YES || bits == SWT.NO || bits == (SWT.YES | SWT.NO) || bits == (SWT.YES | SWT.NO | SWT.CANCEL)) return style;
	if (bits == (SWT.RETRY | SWT.CANCEL) || bits == (SWT.ABORT | SWT.RETRY | SWT.IGNORE)) return style;
	style = (style & ~mask) | SWT.OK;
	return style;
}

char[] fixPercent (String string) {
	int length = string.length ();
	char [] text = new char [length];
	string.getChars (0, length, text, 0);
	int i = 0, j = 0;
	char [] result = new char [length * 2];
	while (i < length) {
		switch (text [i]) {
			case '%':
				result [j++] = '%';
				break;
		}
		result [j++] = text [i++];
	}
	return result;    
}
}
