/*******************************************************************************
 * Copyright (c) 2000, 2008 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.graphics.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.motif.*;
import org.eclipse.swt.*;

/**
 * Instances of this class allow the user to navigate
 * the file system and select a directory.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>(none)</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * IMPORTANT: This class is intended to be subclassed <em>only</em>
 * within the SWT implementation.
 * </p>
 * 
 * @see <a href="http://www.eclipse.org/swt/snippets/#directorydialog">DirectoryDialog snippets</a>
 * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample, Dialog tab</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 * @noextend This class is not intended to be subclassed by clients.
 */
public class DirectoryDialog extends Dialog {
	String filterPath = ""; //$NON-NLS-1$
	boolean cancel = true;
	String message = ""; //$NON-NLS-1$
	static final String SEPARATOR = System.getProperty ("file.separator"); //$NON-NLS-1$
	
/**
 * 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 DirectoryDialog (Shell parent) {
	this (parent, 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.
 * </p>
 *
 * @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 DirectoryDialog (Shell parent, int style) {
	super (parent, checkStyle (parent, style));
	checkSubclass ();
}
int activate (int widget, int client, int call) {
	cancel = client == OS.XmDIALOG_CANCEL_BUTTON;
	OS.XtUnmanageChild (widget);
	return 0;
}
/**
 * Returns the path which the dialog will use to filter
 * the directories it shows.
 *
 * @return the filter path
 * 
 * @see #setFilterPath
 */
public String getFilterPath () {
	return filterPath;
}
/**
 * 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;
}
/**
 * Makes the dialog visible and brings it to the front
 * of the display.
 *
 * @return a string describing the absolute path of the selected directory,
 *         or null if the dialog was cancelled or an error occurred
 *
 * @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 String open () {
	/* Compute the dialog title */	
	/*
	* Feature in Motif.  It is not possible to set a shell
	* title to an empty string.  The fix is to set the title
	* to be a single space.
	*/
	String string = title;
	if (string.length () == 0) string = " "; //$NON-NLS-1$

	/* Use the character encoding for the default locale */
	byte [] buffer1 = Converter.wcsToMbcs (null, string, true);
	int xmStringPtr1 = OS.XmStringParseText (
		buffer1,
		0,
		OS.XmFONTLIST_DEFAULT_TAG, 
		OS.XmCHARSET_TEXT, 
		null,
		0,
		0);

	/* Compute the filter */
	/* Use the character encoding for the default locale */
	byte [] buffer2 = Converter.wcsToMbcs (null, "*", true); //$NON-NLS-1$
	int xmStringPtr2 = OS.XmStringParseText (
		buffer2,
		0,
		OS.XmFONTLIST_DEFAULT_TAG, 
		OS.XmCHARSET_TEXT, 
		null,
		0,
		0);

	/* Compute the filter path */
	if (filterPath == null) filterPath = ""; //$NON-NLS-1$
	/* Use the character encoding for the default locale */
	byte [] buffer3 = Converter.wcsToMbcs (null, filterPath, true);
	int xmStringPtr3 = OS.XmStringParseText (
		buffer3,
		0,
		OS.XmFONTLIST_DEFAULT_TAG, 
		OS.XmCHARSET_TEXT, 
		null,
		0,
		0);

	/* Use the character encoding for the default locale */
	byte [] buffer7 = Converter.wcsToMbcs (null, SWT.getMessage ("SWT_Selection"), true);
	int xmStringPtr4 = OS.XmStringParseText (
		buffer7,
		0,
		OS.XmFONTLIST_DEFAULT_TAG, 
		OS.XmCHARSET_TEXT, 
		null,
		0,
		0);

	/* Create the dialog */
	boolean defaultPos = parent.isVisible ();
	Display display = parent.display;
	int [] argList1 = {
		OS.XmNresizePolicy, OS.XmRESIZE_NONE,
		OS.XmNdialogStyle, OS.XmDIALOG_PRIMARY_APPLICATION_MODAL,
		OS.XmNwidth, OS.XDisplayWidth (display.xDisplay, OS.XDefaultScreen (display.xDisplay)) * 4 / 9,
		OS.XmNdialogTitle, xmStringPtr1,
		OS.XmNpattern, xmStringPtr2,
		OS.XmNdirectory, xmStringPtr3,
		OS.XmNpathMode, OS.XmPATH_MODE_FULL,
		OS.XmNfilterLabelString, xmStringPtr4,
		OS.XmNdefaultPosition, defaultPos ? 1 : 0,
	};

	/*
	* Bug in AIX. The dialog does not respond to input, if the parent
	* is not realized.  The fix is to realize the parent.  
	*/
	if (OS.IsAIX) parent.realizeWidget ();
	int parentHandle = parent.shellHandle;
	/*
	* Feature in Linux.  For some reason, the XmCreateFileSelectionDialog()
	* will not accept NULL for the widget name.  This works fine on the other
	* Motif platforms and in the other XmCreate calls on Linux.  The fix is
	* to pass in a NULL terminated string, not a NULL pointer.
	*/
	byte [] name = new byte [] {0};
	int dialog = OS.XmCreateFileSelectionDialog (parentHandle, name, argList1, argList1.length / 2);
	int child = OS.XmFileSelectionBoxGetChild (dialog, OS.XmDIALOG_HELP_BUTTON);
	if (child != 0) OS.XtUnmanageChild (child);
	child = OS.XmFileSelectionBoxGetChild (dialog, OS.XmDIALOG_LIST);
	if (child != 0) {
		int parent2 = OS.XtParent(child);
		if (parent2 !=0) OS.XtUnmanageChild (parent2);
	}
	child = OS.XmFileSelectionBoxGetChild (dialog, OS.XmDIALOG_LIST_LABEL);
	if (child != 0) OS.XtUnmanageChild (child);
	child = OS.XmFileSelectionBoxGetChild (dialog, OS.XmDIALOG_TEXT);
	if (child != 0) OS.XtUnmanageChild (child);
	child = OS.XmFileSelectionBoxGetChild (dialog, OS.XmDIALOG_SELECTION_LABEL);
	if (child != 0) OS.XtUnmanageChild (child);
	OS.XmStringFree (xmStringPtr1);
	OS.XmStringFree (xmStringPtr2);
	OS.XmStringFree (xmStringPtr3);
	OS.XmStringFree (xmStringPtr4);

	/* Add label widget for message text. */
	/* Use the character encoding for the default locale */
	byte [] buffer4 = Converter.wcsToMbcs (null, message, true);
	int xmString1 = OS.XmStringGenerate(buffer4, null, OS.XmCHARSET_TEXT, null);
	int [] argList2 = {
		OS.XmNlabelType, OS.XmSTRING,
		OS.XmNlabelString, xmString1
	};
	int textArea = OS.XmCreateLabel(dialog, name, argList2, argList2.length/2);
	OS.XtManageChild(textArea);
	OS.XmStringFree (xmString1);

	/* Hook the callbacks. */
	Callback callback = new Callback (this, "activate", 3); //$NON-NLS-1$
	int address = callback.getAddress ();
	if (address == 0) SWT.error (SWT.ERROR_NO_MORE_CALLBACKS);
	OS.XtAddCallback (dialog, OS.XmNokCallback, address, OS.XmDIALOG_OK_BUTTON);
	OS.XtAddCallback (dialog, OS.XmNcancelCallback, address, OS.XmDIALOG_CANCEL_BUTTON);

	/* Open the dialog and dispatch events. */
	cancel = true;
	if (!defaultPos) {
		OS.XtRealizeWidget (dialog);
		int[] argList3 = new int[] {
			OS.XmNwidth, 0,
			OS.XmNheight, 0,
		};
		OS.XtGetValues (dialog, argList3, argList3.length / 2);
		Monitor monitor = parent.getMonitor ();
		Rectangle bounds = monitor.getBounds ();
		int x = bounds.x + (bounds.width - argList3 [1]) / 2;
		int y = bounds.y + (bounds.height - argList3 [3]) / 2;
		int[] argList4 = new int[] {
			OS.XmNx, x,
			OS.XmNy, y,
		};
		OS.XtSetValues (dialog, argList4, argList4.length / 2);
	}
	OS.XtManageChild (dialog);

	/* Should be a pure OS message loop (no SWT AppContext) */
	while (OS.XtIsRealized (dialog) && OS.XtIsManaged (dialog))
		if (!display.readAndDispatch ()) display.sleep ();

	/* Set the new path, file name and filter. */
	String directoryPath=""; //$NON-NLS-1$
	if (!cancel) {
		int [] argList5 = {OS.XmNdirMask, 0};
		OS.XtGetValues (dialog, argList5, argList5.length / 2);
		int xmString3 = argList5 [1];
		int [] table = new int [] {display.tabMapping, display.crMapping};
		int ptr = OS.XmStringUnparse (
			xmString3,
			null,
			OS.XmCHARSET_TEXT,
			OS.XmCHARSET_TEXT,
			table,
			table.length,
			OS.XmOUTPUT_ALL);
		if (ptr != 0) {
			int length = OS.strlen (ptr);
			byte [] buffer = new byte [length];
			OS.memmove (buffer, ptr, length);
			OS.XtFree (ptr);
			/* Use the character encoding for the default locale */
			directoryPath = new String (Converter.mbcsToWcs (null, buffer));
		}
		OS.XmStringFree (xmString3);
		int length = directoryPath.length ();
		if (directoryPath.charAt (length - 1) == '*') {
			directoryPath = directoryPath.substring (0, length - 1);
			length--;
		}
		if (directoryPath.endsWith (SEPARATOR) && !directoryPath.equals (SEPARATOR)) {
			directoryPath = directoryPath.substring (0, length - 1);
		}
		filterPath = directoryPath;
	}

	/* Destroy the dialog and update the display. */
	if (OS.XtIsRealized (dialog)) OS.XtDestroyWidget (dialog);
	callback.dispose ();
	
	if (cancel) return null;
	return directoryPath;
}
/**
 * Sets the path that the dialog will use to filter
 * the directories it shows to the argument, which may
 * be null. If the string is null, then the operating
 * system's default filter path will be used.
 * <p>
 * Note that the path string is platform dependent.
 * For convenience, either '/' or '\' can be used
 * as a path separator.
 * </p>
 *
 * @param string the filter path
 */
public void setFilterPath (String string) {
	filterPath = string;
}
/**
 * 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;
}
}