/*******************************************************************************
 * Copyright (c) 2000, 2014 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.graphics;


import org.eclipse.swt.*;
import org.eclipse.swt.internal.win32.*;

/**
 * Instances of this class manage operating system resources that
 * specify the appearance of the on-screen pointer. To create a
 * cursor you specify the device and either a simple cursor style
 * describing one of the standard operating system provided cursors
 * or the image and mask data for the desired appearance.
 * <p>
 * Application code must explicitly invoke the <code>Cursor.dispose()</code>
 * method to release the operating system resources managed by each instance
 * when those instances are no longer required.
 * </p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>
 *   CURSOR_ARROW, CURSOR_WAIT, CURSOR_CROSS, CURSOR_APPSTARTING, CURSOR_HELP,
 *   CURSOR_SIZEALL, CURSOR_SIZENESW, CURSOR_SIZENS, CURSOR_SIZENWSE, CURSOR_SIZEWE,
 *   CURSOR_SIZEN, CURSOR_SIZES, CURSOR_SIZEE, CURSOR_SIZEW, CURSOR_SIZENE, CURSOR_SIZESE,
 *   CURSOR_SIZESW, CURSOR_SIZENW, CURSOR_UPARROW, CURSOR_IBEAM, CURSOR_NO, CURSOR_HAND
 * </dd>
 * </dl>
 * <p>
 * Note: Only one of the above styles may be specified.
 * </p>
 *
 * @see <a href="http://www.eclipse.org/swt/snippets/#cursor">Cursor snippets</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 */
public final class Cursor extends Resource {

	/**
	 * the handle to the OS cursor resource
	 * (Warning: This field is platform dependent)
	 * <p>
	 * <b>IMPORTANT:</b> This field is <em>not</em> part of the SWT
	 * public API. It is marked public only so that it can be shared
	 * within the packages provided by SWT. It is not available on all
	 * platforms and should never be accessed from application code.
	 * </p>
	 *
	 * @noreference This field is not intended to be referenced by clients.
	 */
	public long /*int*/ handle;

	boolean isIcon;

/**
 * Prevents uninitialized instances from being created outside the package.
 */
Cursor(Device device) {
	super(device);
}

/**
 * Constructs a new cursor given a device and a style
 * constant describing the desired cursor appearance.
 * <p>
 * You must dispose the cursor when it is no longer required.
 * </p>
 * NOTE:
 * It is recommended to use {@link org.eclipse.swt.widgets.Display#getSystemCursor(int)}
 * instead of using this constructor. This way you can avoid the
 * overhead of disposing the Cursor resource.
 *
 * @param device the device on which to allocate the cursor
 * @param style the style of cursor to allocate
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if device is null and there is no current device</li>
 *    <li>ERROR_INVALID_ARGUMENT - when an unknown style is specified</li>
 * </ul>
 * @exception SWTError <ul>
 *    <li>ERROR_NO_HANDLES - if a handle could not be obtained for cursor creation</li>
 * </ul>
 *
 * @see SWT#CURSOR_ARROW
 * @see SWT#CURSOR_WAIT
 * @see SWT#CURSOR_CROSS
 * @see SWT#CURSOR_APPSTARTING
 * @see SWT#CURSOR_HELP
 * @see SWT#CURSOR_SIZEALL
 * @see SWT#CURSOR_SIZENESW
 * @see SWT#CURSOR_SIZENS
 * @see SWT#CURSOR_SIZENWSE
 * @see SWT#CURSOR_SIZEWE
 * @see SWT#CURSOR_SIZEN
 * @see SWT#CURSOR_SIZES
 * @see SWT#CURSOR_SIZEE
 * @see SWT#CURSOR_SIZEW
 * @see SWT#CURSOR_SIZENE
 * @see SWT#CURSOR_SIZESE
 * @see SWT#CURSOR_SIZESW
 * @see SWT#CURSOR_SIZENW
 * @see SWT#CURSOR_UPARROW
 * @see SWT#CURSOR_IBEAM
 * @see SWT#CURSOR_NO
 * @see SWT#CURSOR_HAND
 * @see #dispose()
 */
public Cursor(Device device, int style) {
	super(device);
	long /*int*/ lpCursorName = 0;
	switch (style) {
		case SWT.CURSOR_HAND: 		lpCursorName = OS.IDC_HAND; break;
		case SWT.CURSOR_ARROW: 		lpCursorName = OS.IDC_ARROW; break;
		case SWT.CURSOR_WAIT: 		lpCursorName = OS.IDC_WAIT; break;
		case SWT.CURSOR_CROSS: 		lpCursorName = OS.IDC_CROSS; break;
		case SWT.CURSOR_APPSTARTING: 	lpCursorName = OS.IDC_APPSTARTING; break;
		case SWT.CURSOR_HELP: 		lpCursorName = OS.IDC_HELP; break;
		case SWT.CURSOR_SIZEALL: 	lpCursorName = OS.IDC_SIZEALL; break;
		case SWT.CURSOR_SIZENESW: 	lpCursorName = OS.IDC_SIZENESW; break;
		case SWT.CURSOR_SIZENS: 	lpCursorName = OS.IDC_SIZENS; break;
		case SWT.CURSOR_SIZENWSE: 	lpCursorName = OS.IDC_SIZENWSE; break;
		case SWT.CURSOR_SIZEWE: 	lpCursorName = OS.IDC_SIZEWE; break;
		case SWT.CURSOR_SIZEN: 		lpCursorName = OS.IDC_SIZENS; break;
		case SWT.CURSOR_SIZES: 		lpCursorName = OS.IDC_SIZENS; break;
		case SWT.CURSOR_SIZEE: 		lpCursorName = OS.IDC_SIZEWE; break;
		case SWT.CURSOR_SIZEW: 		lpCursorName = OS.IDC_SIZEWE; break;
		case SWT.CURSOR_SIZENE: 	lpCursorName = OS.IDC_SIZENESW; break;
		case SWT.CURSOR_SIZESE: 	lpCursorName = OS.IDC_SIZENWSE; break;
		case SWT.CURSOR_SIZESW: 	lpCursorName = OS.IDC_SIZENESW; break;
		case SWT.CURSOR_SIZENW: 	lpCursorName = OS.IDC_SIZENWSE; break;
		case SWT.CURSOR_UPARROW: 	lpCursorName = OS.IDC_UPARROW; break;
		case SWT.CURSOR_IBEAM: 		lpCursorName = OS.IDC_IBEAM; break;
		case SWT.CURSOR_NO: 		lpCursorName = OS.IDC_NO; break;
		default:
			SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	}
	handle = OS.LoadCursor(0, lpCursorName);
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	init();
}

/**
 * Constructs a new cursor given a device, image and mask
 * data describing the desired cursor appearance, and the x
 * and y coordinates of the <em>hotspot</em> (that is, the point
 * within the area covered by the cursor which is considered
 * to be where the on-screen pointer is "pointing").
 * <p>
 * The mask data is allowed to be null, but in this case the source
 * must be an ImageData representing an icon that specifies both
 * color data and mask data.
 * <p>
 * You must dispose the cursor when it is no longer required.
 * </p>
 *
 * @param device the device on which to allocate the cursor
 * @param source the color data for the cursor
 * @param mask the mask data for the cursor (or null)
 * @param hotspotX the x coordinate of the cursor's hotspot
 * @param hotspotY the y coordinate of the cursor's hotspot
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if device is null and there is no current device</li>
 *    <li>ERROR_NULL_ARGUMENT - if the source is null</li>
 *    <li>ERROR_NULL_ARGUMENT - if the mask is null and the source does not have a mask</li>
 *    <li>ERROR_INVALID_ARGUMENT - if the source and the mask are not the same
 *          size, or if the hotspot is outside the bounds of the image</li>
 * </ul>
 * @exception SWTError <ul>
 *    <li>ERROR_NO_HANDLES - if a handle could not be obtained for cursor creation</li>
 * </ul>
 *
 * @see #dispose()
 */
public Cursor(Device device, ImageData source, ImageData mask, int hotspotX, int hotspotY) {
	super(device);
	if (source == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (mask == null) {
		if (source.getTransparencyType() != SWT.TRANSPARENCY_MASK) {
			SWT.error(SWT.ERROR_NULL_ARGUMENT);
		}
		mask = source.getTransparencyMask();
	}
	/* Check the bounds. Mask must be the same size as source */
	if (mask.width != source.width || mask.height != source.height) {
		SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	}
	/* Check the hotspots */
	if (hotspotX >= source.width || hotspotX < 0 ||
		hotspotY >= source.height || hotspotY < 0) {
		SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	}
	/* Convert depth to 1 */
	mask = ImageData.convertMask(mask);
	source = ImageData.convertMask(source);

	/* Make sure source and mask scanline pad is 2 */
	byte[] sourceData = ImageData.convertPad(source.data, source.width, source.height, source.depth, source.scanlinePad, 2);
	byte[] maskData = ImageData.convertPad(mask.data, mask.width, mask.height, mask.depth, mask.scanlinePad, 2);

	/* Create the cursor */
	long /*int*/ hInst = OS.GetModuleHandle(null);
	handle = OS.CreateCursor(hInst, hotspotX, hotspotY, source.width, source.height, sourceData, maskData);
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	init();
}

/**
 * Constructs a new cursor given a device, image data describing
 * the desired cursor appearance, and the x and y coordinates of
 * the <em>hotspot</em> (that is, the point within the area
 * covered by the cursor which is considered to be where the
 * on-screen pointer is "pointing").
 * <p>
 * You must dispose the cursor when it is no longer required.
 * </p>
 *
 * @param device the device on which to allocate the cursor
 * @param source the image data for the cursor
 * @param hotspotX the x coordinate of the cursor's hotspot
 * @param hotspotY the y coordinate of the cursor's hotspot
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if device is null and there is no current device</li>
 *    <li>ERROR_NULL_ARGUMENT - if the image is null</li>
 *    <li>ERROR_INVALID_ARGUMENT - if the hotspot is outside the bounds of the
 * 		 image</li>
 * </ul>
 * @exception SWTError <ul>
 *    <li>ERROR_NO_HANDLES - if a handle could not be obtained for cursor creation</li>
 * </ul>
 *
 * @see #dispose()
 *
 * @since 3.0
 */
public Cursor(Device device, ImageData source, int hotspotX, int hotspotY) {
	super(device);
	if (source == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	/* Check the hotspots */
	if (hotspotX >= source.width || hotspotX < 0 ||
		hotspotY >= source.height || hotspotY < 0) {
		SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	}
	long /*int*/ hBitmap = 0;
	long /*int*/ hMask = 0;
	if (source.maskData == null && source.transparentPixel == -1 && (source.alpha != -1 || source.alphaData != null)) {
		PaletteData palette = source.palette;
		PaletteData newPalette = new PaletteData(0xFF00, 0xFF0000, 0xFF000000);
		ImageData img = new ImageData(source.width, source.height, 32, newPalette);
		if (palette.isDirect) {
			ImageData.blit(ImageData.BLIT_SRC,
				source.data, source.depth, source.bytesPerLine, source.getByteOrder(), 0, 0, source.width, source.height, palette.redMask, palette.greenMask, palette.blueMask,
				ImageData.ALPHA_OPAQUE, null, 0, 0, 0,
				img.data, img.depth, img.bytesPerLine, img.getByteOrder(), 0, 0, img.width, img.height, newPalette.redMask, newPalette.greenMask, newPalette.blueMask,
				false, false);
		} else {
			RGB[] rgbs = palette.getRGBs();
			int length = rgbs.length;
			byte[] srcReds = new byte[length];
			byte[] srcGreens = new byte[length];
			byte[] srcBlues = new byte[length];
			for (int i = 0; i < rgbs.length; i++) {
				RGB rgb = rgbs[i];
				if (rgb == null) continue;
				srcReds[i] = (byte)rgb.red;
				srcGreens[i] = (byte)rgb.green;
				srcBlues[i] = (byte)rgb.blue;
			}
			ImageData.blit(ImageData.BLIT_SRC,
				source.data, source.depth, source.bytesPerLine, source.getByteOrder(), 0, 0, source.width, source.height, srcReds, srcGreens, srcBlues,
				ImageData.ALPHA_OPAQUE, null, 0, 0, 0,
				img.data, img.depth, img.bytesPerLine, img.getByteOrder(), 0, 0, img.width, img.height, newPalette.redMask, newPalette.greenMask, newPalette.blueMask,
				false, false);
		}
		hBitmap = Image.createDIB(source.width, source.height, 32);
		if (hBitmap == 0) SWT.error(SWT.ERROR_NO_HANDLES);
		BITMAP dibBM = new BITMAP();
		OS.GetObject(hBitmap, BITMAP.sizeof, dibBM);
		byte[] srcData = img.data;
		if (source.alpha != -1) {
			for (int i = 3; i < srcData.length; i+=4) {
				srcData[i] = (byte)source.alpha;
			}
		} else if (source.alphaData != null) {
			for (int sp = 3, ap=0; sp < srcData.length; sp+=4, ap++) {
				srcData[sp] = source.alphaData[ap];
			}
		}
		OS.MoveMemory(dibBM.bmBits, srcData, srcData.length);
		hMask = OS.CreateBitmap(source.width, source.height, 1, 1, new byte[(((source.width + 7) / 8) + 3) / 4 * 4 * source.height]);
		if (hMask == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	} else {
		ImageData mask = source.getTransparencyMask();
		long /*int*/ [] result = Image.init(this.device, null, source, mask);
		hBitmap = result[0];
		hMask = result[1];
	}
	/* Create the icon */
	ICONINFO info = new ICONINFO();
	info.fIcon = false;
	info.hbmColor = hBitmap;
	info.hbmMask = hMask;
	info.xHotspot = hotspotX;
	info.yHotspot = hotspotY;
	handle = OS.CreateIconIndirect(info);
	OS.DeleteObject(hBitmap);
	OS.DeleteObject(hMask);
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	isIcon = true;
	init();
}

@Override
void destroy () {
	/*
	* It is an error in Windows to destroy the current
	* cursor.  Check that the cursor that is about to
	* be destroyed is the current cursor.  If so, set
	* the current cursor to be IDC_ARROW.  Note that
	* Windows shares predefined cursors so the call to
	* LoadCursor() does not leak.
	*/
	// TEMPORARY CODE
//	if (OS.GetCursor() == handle) {
//		OS.SetCursor(OS.LoadCursor(0, OS.IDC_ARROW));
//	}

	if (isIcon) {
		OS.DestroyIcon(handle);
	} else {
		/*
	 	* The MSDN states that one should not destroy a shared
	 	* cursor, that is, one obtained from LoadCursor.
	 	* However, it does not appear to do any harm, so rather
	 	* than keep track of how a cursor was created, we just
	 	* destroy them all. If this causes problems in the future,
	 	* put the flag back in.
		*/
		OS.DestroyCursor(handle);
	}
	handle = 0;
}

/**
 * Compares the argument to the receiver, and returns true
 * if they represent the <em>same</em> object using a class
 * specific comparison.
 *
 * @param object the object to compare with this object
 * @return <code>true</code> if the object is the same as this object and <code>false</code> otherwise
 *
 * @see #hashCode
 */
@Override
public boolean equals (Object object) {
	if (object == this) return true;
	if (!(object instanceof Cursor)) return false;
	Cursor cursor = (Cursor) object;
	return device == cursor.device && handle == cursor.handle;
}

/**
 * Returns an integer hash code for the receiver. Any two
 * objects that return <code>true</code> when passed to
 * <code>equals</code> must return the same value for this
 * method.
 *
 * @return the receiver's hash
 *
 * @see #equals
 */
@Override
public int hashCode () {
	return (int)/*64*/handle;
}

/**
 * Returns <code>true</code> if the cursor has been disposed,
 * and <code>false</code> otherwise.
 * <p>
 * This method gets the dispose state for the cursor.
 * When a cursor has been disposed, it is an error to
 * invoke any other method (except {@link #dispose()}) using the cursor.
 *
 * @return <code>true</code> when the cursor is disposed and <code>false</code> otherwise
 */
@Override
public boolean isDisposed() {
	return handle == 0;
}

/**
 * Returns a string containing a concise, human-readable
 * description of the receiver.
 *
 * @return a string representation of the receiver
 */
@Override
public String toString () {
	if (isDisposed()) return "Cursor {*DISPOSED*}";
	return "Cursor {" + handle + "}";
}

/**
 * Invokes platform specific functionality to allocate a new cursor.
 * <p>
 * <b>IMPORTANT:</b> This method is <em>not</em> part of the public
 * API for <code>Cursor</code>. It is marked public only so that it
 * can be shared within the packages provided by SWT. It is not
 * available on all platforms, and should never be called from
 * application code.
 * </p>
 *
 * @param device the device on which to allocate the color
 * @param handle the handle for the cursor
 * @return a new cursor object containing the specified device and handle
 *
 * @noreference This method is not intended to be referenced by clients.
 */
public static Cursor win32_new(Device device, int handle) {
	Cursor cursor = new Cursor(device);
	cursor.handle = handle;
	return cursor;
}

}
