/*******************************************************************************

 * Copyright (c) 2000, 2007 IBM Corporation and others.

 * Portion Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies).

 * 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

 *     Nokia Corporation - Qt implementation

 *******************************************************************************/

package org.eclipse.swt.widgets;

import org.eclipse.swt.SWT;

import org.eclipse.swt.SWTException;

import org.eclipse.swt.events.DisposeEvent;

import org.eclipse.swt.events.DisposeListener;

import org.eclipse.swt.internal.qt.OS;

/**

 * Instances of this class allow the user to navigate the file system and select

 * or enter a file name.

 * <dl>

 * <dt><b>Styles:</b></dt>

 * <dd>SAVE, OPEN, MULTI</dd>

 * <dt><b>Events:</b></dt>

 * <dd>(none)</dd>

 * </dl>

 * <p>

 * Note: Only one of the styles SAVE and OPEN may be specified.

 * </p>

 * <p>

 * IMPORTANT: This class is intended to be subclassed <em>only</em> within the

 * SWT implementation.

 * </p>

 */

public class FileDialog extends Dialog {

	String[] filterNames;

	String[] filterExtensions;

	String filterPath = "";

	String fileName;

	String[] fileNames = new String[] {};

	int filterIndex = -1;

	static final String EXTENSION_SEPARATOR = ";;";

	String dialogID;

	static int dialogCount;

	/**

	 * 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 FileDialog(Shell parent) {

		this(parent, SWT.NULL);

	}

	/**

	 * 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 FileDialog(Shell parent, int style) {

		super(parent, checkStyle(parent, style));

		checkSubclass();

		dialogCount++;

		dialogID = toString() + String.valueOf(dialogCount);

	}

	static int checkStyle(Shell parent, int style) {

		style &= ~SWT.MIRRORED;

		if ((style & SWT.RIGHT_TO_LEFT) == 0) {

			if (parent != null) {

				if ((parent.style & SWT.RIGHT_TO_LEFT) != 0)

					style |= SWT.RIGHT_TO_LEFT;

			}

		}

		if ((style & SWT.OPEN) != 0 && (style & SWT.SAVE) != 0) {

			style &= ~SWT.OPEN;

		}

		if ((style & SWT.SAVE) != 0 && (style & SWT.MULTI) != 0) {

			style &= ~SWT.MULTI;

		}

		if ((style & SWT.LEFT_TO_RIGHT) != 0

				&& (style & SWT.RIGHT_TO_LEFT) != 0) {

			style &= ~SWT.LEFT_TO_RIGHT;

		}

		return style;

	}

	/**

	 * Returns the path of the first file that was selected in the dialog

	 * relative to the filter path, or an empty string if no such file has been

	 * selected.

	 *

	 * @return the relative path of the file

	 */

	public String getFileName() {

		return fileName;

	}

	/**

	 * Returns a (possibly empty) array with the paths of all files that were

	 * selected in the dialog relative to the filter path.

	 *

	 * @return the relative paths of the files

	 */

	public String[] getFileNames() {

		return fileNames;

	}

	/**

	 * Returns the file extensions which the dialog will use to filter the files

	 * it shows.

	 *

	 * @return the file extensions filter

	 */

	public String[] getFilterExtensions() {

		return filterExtensions;

	}

	/**

	 * Get the 0-based index of the file extension filter which was selected by

	 * the user, or -1 if no filter was selected.

	 * <p>

	 * This is an index into the FilterExtensions array and the FilterNames

	 * array.

	 * </p>

	 *

	 * @return index the file extension filter index

	 *

	 * @see #getFilterExtensions

	 * @see #getFilterNames

	 *

	 * @since 3.4

	 */

	public int getFilterIndex() {

		return filterIndex;

	}

	/**

	 * Returns the names that describe the filter extensions which the dialog

	 * will use to filter the files it shows.

	 *

	 * @return the list of filter names

	 */

	public String[] getFilterNames() {

		return filterNames;

	}

	/**

	 * Returns the directory path that the dialog will use, or an empty string

	 * if this is not set. File names in this path will appear in the dialog,

	 * filtered according to the filter extensions.

	 *

	 * @return the directory path string

	 *

	 * @see #setFilterExtensions

	 */

	public String getFilterPath() {

		return filterPath;

	}

	/**

	 * Makes the dialog visible and brings it to the front of the display.

	 *

	 * @return a string describing the absolute path of the first selected file,

	 *         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() {

		checkDialog();

		/*

		 * put filters and filter names into single string

		 */

		String filter = "";

		int filterCount = filterExtensions != null ? filterExtensions.length

				: -1;

		int filterNameCount = filterNames != null ? filterNames.length : -1;

		if (filterCount > 0) {

			filter += (filterNameCount > 0 ? filterNames[0] + " " : "") + "("

					+ filterExtensions[0] + ")";

			for (int i = 1; i < filterCount; i++) {

				filter += EXTENSION_SEPARATOR

						+ (i < filterNameCount ? filterNames[i] + " " : "")

						+ "(" + filterExtensions[i] + ")";

			}

		}

		/*

		 * get selected filter

		 */

		String selectedFilter = filterIndex > -1 && filterIndex < filterCount ? filterExtensions[filterIndex]

				: "";

		/*

		 * form full path

		 */

		int filterPathLength = filterPath != null ? filterPath.length() : 0;

		String fullPath = filterPathLength > 0 ? filterPath : "";

		int fileNameLength = fileName != null ? fileName.length() : 0;

		if (filterPathLength > 0 && fileNameLength > 0

				&& filterPath.charAt(filterPathLength - 1) != SEPARATOR) {

			/*

			 * adding a separator between filterPath and file name

			 */

			fullPath += SEPARATOR;

		}

		if (fileNameLength > 0) {

			fullPath += fileName;

		}

		DisposeListener listener = new DisposeListener() {

			public void widgetDisposed(DisposeEvent e) {

				if (e.widget == parent) {

					/*

					 * close dialogs which opened on top of parent

					 */

					OS.QDialog_swt_closeDialogs(parent.handle,

							dialogID);

				}

			}

		};

		/*

		 * listen to parent dispose event

		 */

		parent.addDisposeListener(listener);

		/*

		 * open dialog

		 */

		int qtLayoutDirection = (style & SWT.RIGHT_TO_LEFT) != 0 ? OS.QT_RIGHTTOLEFT

				: OS.QT_LEFTTORIGHT;

		String[] resultStrings;

		if ((style & SWT.SAVE) != 0) {

			resultStrings = OS.QFileDialog_swt_getSaveFileName(parent.handle,

					title, fullPath, filter, selectedFilter, dialogID,

					qtLayoutDirection);

		} else {

			if ((style & SWT.MULTI) != 0) {

				resultStrings = OS.QFileDialog_swt_getOpenFileNames(

						parent.handle, title, fullPath, filter, selectedFilter,

						dialogID, qtLayoutDirection);

			} else {

				resultStrings = OS.QFileDialog_swt_getOpenFileName(

						parent.handle, title, fullPath, filter, selectedFilter,

						dialogID, qtLayoutDirection);

			}

		}

		if (parent != null && !parent.isDisposed()) {

			parent.removeDisposeListener(listener);

		}

		parseResult(resultStrings);

		return resultStrings != null && resultStrings.length > 0 ? resultStrings[0]

				: null;

	}

	/*

	 * Array Parameter 'result' stores full paths of selected files with the

	 * last one in the array storing the selected filter

	 */

	private void parseResult(String[] result) {

		filterPath = null;

		fileNames = null;

		fileName = null;

		filterIndex = -1;

		if (result == null) {

			return;

		}

		int count = result.length;

		if (count < 1) {

			return;

		}

		/*

		 * get the first file name and filter path from dialog result

		 */

		fileNames = new String[count - 1];

		String fullPath = result[0];

		int separatorPos = -1;

		if (fullPath != null && fullPath.length() > 0) {

			separatorPos = fullPath.lastIndexOf(SEPARATOR);

			fileName = fullPath.substring(separatorPos + 1);

			fileNames[0] = fileName;

			filterPath = fullPath.substring(0, separatorPos);

		}

		/*

		 * get rest file names from dialog result

		 */

		for (int i = 1; i < count - 1; i++) {

			fullPath = result[i];

			if (fullPath != null && fullPath.length() > 0) {

				separatorPos = fullPath.lastIndexOf(SEPARATOR);

				fileNames[i] = fullPath.substring(separatorPos + 1);

			} else {

				fileNames[i] = null;

			}

		}

		/*

		 * get filter index

		 */

		int filterCount = filterExtensions==null ? 0 : filterExtensions.length;

		String selectedFilter = result[count - 1];

		filterIndex = -1;

		if (filterCount > 0 && selectedFilter != null) {

			selectedFilter = selectedFilter.substring(selectedFilter

					.indexOf('(') + 1);

			selectedFilter = selectedFilter.substring(0, selectedFilter

					.indexOf(')'));

			for (int i = 0; i < filterCount; i++) {

				if (filterExtensions[i].equals(selectedFilter)) {

					filterIndex = i;

					break;

				}

			}

		}

	}

	/**

	 * Set the initial filename which the dialog will select by default when

	 * opened to the argument, which may be null. The name will be prefixed with

	 * the filter path when one is supplied.

	 *

	 * @param string

	 *            the file name

	 */

	public void setFileName(String string) {

		fileName = string;

	}

	/**

	 * Set the file extensions which the dialog will use to filter the files it

	 * shows to the argument, which may be null.

	 * <p>

	 * The strings are platform specific. For example, on Windows, an extension

	 * filter string is typically of the form "*.extension", where "*.*" matches

	 * all files.

	 * </p>

	 *

	 * @param extensions

	 *            the file extension filter

	 *

	 * @see #setFilterNames to specify the user-friendly names corresponding to

	 *      the extensions

	 */

	public void setFilterExtensions(String[] extensions) {

		filterExtensions = extensions;

	}

	/**

	 * Set the 0-based index of the file extension filter which the dialog will

	 * use initially to filter the files it shows to the argument.

	 * <p>

	 * This is an index into the FilterExtensions array and the FilterNames

	 * array.

	 * </p>

	 *

	 * @param index

	 *            the file extension filter index

	 *

	 * @see #setFilterExtensions

	 * @see #setFilterNames

	 *

	 * @since 3.4

	 */

	public void setFilterIndex(int index) {

		filterIndex = index;

	}

	/**

	 * Sets the the names that describe the filter extensions which the dialog

	 * will use to filter the files it shows to the argument, which may be null.

	 * <p>

	 * Each name is a user-friendly short description shown for its

	 * corresponding filter. The <code>names</code> array must be the same

	 * length as the <code>extensions</code> array.

	 * </p>

	 *

	 * @param names

	 *            the list of filter names, or null for no filter names

	 *

	 * @see #setFilterExtensions

	 */

	public void setFilterNames(String[] names) {

		filterNames = names;

	}

	/**

	 * Sets the directory path that the dialog will use to the argument, which

	 * may be null. File names in this path will appear in the dialog, filtered

	 * according to the filter extensions. 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 directory path

	 *

	 * @see #setFilterExtensions

	 */

	public void setFilterPath(String string) {

		filterPath = string;

	}

	void checkDialog() {

		if (parent == null)

			error(SWT.ERROR_WIDGET_DISPOSED);

		if (parent.isDisposed())

			error(SWT.ERROR_WIDGET_DISPOSED);

		Display display = parent.display;

		if (display == null)

			error(SWT.ERROR_WIDGET_DISPOSED);

		if (display.thread != Thread.currentThread())

			error(SWT.ERROR_THREAD_INVALID_ACCESS);

	}

}