/*******************************************************************************
 * Copyright (c) 2000, 2007 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
 *******************************************************************************/
module dwt.graphics.Device;

import dwt.graphics.Color;
import dwt.graphics.Font;
import dwt.graphics.Drawable;
import dwt.graphics.DeviceData;
import dwt.graphics.Rectangle;
import dwt.graphics.FontData;
import dwt.graphics.Font;
import dwt.graphics.GCData;
import dwt.dwthelper.Runnable;
import dwt.SWT;
import dwt.SWTError;
import dwt.internal.Compatibility;
import dwt.internal.gtk.OS;

import tango.core.Exception;
import tango.stdc.stringz;
import tango.io.Stdout;

/**
 * This class is the abstract superclass of all device objects,
 * such as the Display device and the Printer device. Devices
 * can have a graphics context (GC) created for them, and they
 * can be drawn on by sending messages to the associated GC.
 */
public abstract class Device : Drawable {
	/**
	 * the handle to the X Display
	 * (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 protected 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>
	 */
	protected void* xDisplay;
	GtkWidget* shellHandle;

	/* Debugging */
	public static bool DEBUG;
	bool debugging;
	bool tracking;
	TracedException [] errors;
	Object [] objects;

	/* Colormap and reference count */
	GdkColor *[] gdkColors;
	int [] colorRefCount;

	/* Disposed flag */
	bool disposed;

	/* Warning and Error Handlers */
	//int /*long*/ logProcFld;
	//GLogFunc logCallback;
	//NOT DONE - get list of valid names
	char[] [] log_domains = ["GLib-GObject"[], "GLib", "GObject", "Pango", "ATK", "GdkPixbuf", "Gdk", "Gtk", "GnomeVFS"];
	int [] handler_ids;// = new int [log_domains.length];
	int warningLevel;

	/* X Warning and Error Handlers */
    static extern(C) int function(void *) mXIOErrorHandler;
    static extern(C) int function(void *, XErrorEvent *) mXErrorHandler;
	//static int mXErrorCallback, mXIOErrorCallback;

	static int /*long*/ XErrorProc, XIOErrorProc, XNullErrorProc, XNullIOErrorProc;
	static Device[] Devices;

	/*
	* The following colors are listed in the Windows
	* Programmer's Reference as the colors in the default
	* palette.
	*/
	Color COLOR_BLACK, COLOR_DARK_RED, COLOR_DARK_GREEN, COLOR_DARK_YELLOW, COLOR_DARK_BLUE;
	Color COLOR_DARK_MAGENTA, COLOR_DARK_CYAN, COLOR_GRAY, COLOR_DARK_GRAY, COLOR_RED;
	Color COLOR_GREEN, COLOR_YELLOW, COLOR_BLUE, COLOR_MAGENTA, COLOR_CYAN, COLOR_WHITE;

	/* System Font */
	Font systemFont;

	PangoTabArray* emptyTab;

	bool useXRender;

	static bool CAIRO_LOADED;

	static Object CREATE_LOCK;

	/*
	* TEMPORARY CODE. When a graphics object is
	* created and the device parameter is null,
	* the current Display is used. This presents
	* a problem because SWT graphics does not
	* reference classes in SWT widgets. The correct
	* fix is to remove this feature. Unfortunately,
	* too many application programs rely on this
	* feature.
	*
	* This code will be removed in the future.
	*/
	protected static Device CurrentDevice;
	protected static Runnable DeviceFinder;

synchronized static void static_this(){
    CREATE_LOCK = new Object();
    Devices = new Device[4];
}
/*
* TEMPORARY CODE.
*/
static synchronized Device getDevice () {
	if (DeviceFinder !is null) DeviceFinder.run();
	Device device = CurrentDevice;
	CurrentDevice = null;
	return device;
}

/**
 * Constructs a new instance of this class.
 * <p>
 * You must dispose the device when it is no longer required.
 * </p>
 *
 * @see #create
 * @see #init
 *
 * @since 3.1
 */
public this() {
	this(null);
}

/**
 * Constructs a new instance of this class.
 * <p>
 * You must dispose the device when it is no longer required.
 * </p>
 *
 * @param data the DeviceData which describes the receiver
 *
 * @see #create
 * @see #init
 * @see DeviceData
 */
public this(DeviceData data) {
    handler_ids = new int [log_domains.length];
    debugging = DEBUG;
    tracking = DEBUG;

	synchronized (CREATE_LOCK) {
		if (data !is null) {
			debugging = data.debugging;
			tracking = data.tracking;
		}
		if (tracking) {
			errors = new TracedException [128];
			objects = new Object [128];
		}
		create (data);
		init ();
		register (this);

		/* Initialize the system font slot */
		systemFont = getSystemFont ();
	}
}

void checkCairo() {
}

/**
 * Throws an <code>SWTException</code> if the receiver can not
 * be accessed by the caller. This may include both checks on
 * the state of the receiver and more generally on the entire
 * execution context. This method <em>should</em> be called by
 * device implementors to enforce the standard SWT invariants.
 * <p>
 * Currently, it is an error to invoke any method (other than
 * <code>isDisposed()</code> and <code>dispose()</code>) on a
 * device that has had its <code>dispose()</code> method called.
 * </p><p>
 * In future releases of SWT, there may be more or fewer error
 * checks and exceptions may be thrown for different reasons.
 * <p>
 *
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
protected void checkDevice () {
	if (disposed) SWT.error(SWT.ERROR_DEVICE_DISPOSED);
}

/**
 * Creates the device in the operating system.  If the device
 * does not have a handle, this method may do nothing depending
 * on the device.
 * <p>
 * This method is called before <code>init</code>.
 * </p><p>
 * Subclasses are supposed to reimplement this method and not
 * call the <code>super</code> implementation.
 * </p>
 *
 * @param data the DeviceData which describes the receiver
 *
 * @see #init
 */
protected void create (DeviceData data) {
}

/**
 * Disposes of the operating system resources associated with
 * the receiver. After this method has been invoked, the receiver
 * will answer <code>true</code> when sent the message
 * <code>isDisposed()</code>.
 *
 * @see #release
 * @see #destroy
 * @see #checkDevice
 */
public void dispose () {
	if (isDisposed()) return;
	checkDevice ();
	release ();
	destroy ();
	deregister (this);
	xDisplay = null;
	disposed = true;
	if (tracking) {
		objects = null;
		errors = null;
	}
}

void dispose_Object (Object object) {
	for (int i=0; i<objects.length; i++) {
		if (objects [i] is object) {
			objects [i] = null;
			errors [i] = null;
			return;
		}
	}
}

static synchronized Device findDevice (void* xDisplay) {
	for (int i=0; i<Devices.length; i++) {
		Device device = Devices [i];
		if (device !is null && device.xDisplay is xDisplay) {
			return device;
		}
	}
	return null;
}

synchronized static void deregister (Device device) {
	for (int i=0; i<Devices.length; i++) {
		if (device is Devices [i]) Devices [i] = null;
	}
}

/**
 * Destroys the device in the operating system and releases
 * the device's handle.  If the device does not have a handle,
 * this method may do nothing depending on the device.
 * <p>
 * This method is called after <code>release</code>.
 * </p><p>
 * Subclasses are supposed to reimplement this method and not
 * call the <code>super</code> implementation.
 * </p>
 *
 * @see #dispose
 * @see #release
 */
protected void destroy () {
}

/**
 * Returns a rectangle describing the receiver's size and location.
 *
 * @return the bounding rectangle
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public Rectangle getBounds () {
	checkDevice ();
	return new Rectangle(0, 0, 0, 0);
}

/**
 * Returns a <code>DeviceData</code> based on the receiver.
 * Modifications made to this <code>DeviceData</code> will not
 * affect the receiver.
 *
 * @return a <code>DeviceData</code> containing the device's data and attributes
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 *
 * @see DeviceData
 */
public DeviceData getDeviceData () {
	checkDevice();
	DeviceData data = new DeviceData ();
	data.debugging = debugging;
	data.tracking = tracking;
	int count = 0, length = 0;
	if (tracking) length = objects.length;
	for (int i=0; i<length; i++) {
		if (objects [i] !is null) count++;
	}
	int index = 0;
	data.objects = new Object [count];
	data.errors = new TracedException [count];
	for (int i=0; i<length; i++) {
		if (objects [i] !is null) {
			data.objects [index] = objects [i];
			data.errors [index] = errors [i];
			index++;
		}
	}
	return data;
}

/**
 * Returns a rectangle which describes the area of the
 * receiver which is capable of displaying data.
 *
 * @return the client area
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 *
 * @see #getBounds
 */
public Rectangle getClientArea () {
	checkDevice ();
	return getBounds ();
}

/**
 * Returns the bit depth of the screen, which is the number of
 * bits it takes to represent the number of unique colors that
 * the screen is currently capable of displaying. This number
 * will typically be one of 1, 8, 15, 16, 24 or 32.
 *
 * @return the depth of the screen
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public int getDepth () {
	checkDevice ();
	return 0;
}

/**
 * Returns a point whose x coordinate is the horizontal
 * dots per inch of the display, and whose y coordinate
 * is the vertical dots per inch of the display.
 *
 * @return the horizontal and vertical DPI
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public Point getDPI () {
	checkDevice ();
	return new Point (72, 72);
}

/**
 * Returns <code>FontData</code> objects which describe
 * the fonts that match the given arguments. If the
 * <code>faceName</code> is null, all fonts will be returned.
 *
 * @param faceName the name of the font to look for, or null
 * @param scalable if true only scalable fonts are returned, otherwise only non-scalable fonts are returned.
 * @return the matching font data
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public FontData[] getFontList (char[] faceName, bool scalable) {
	checkDevice ();
	if (!scalable) return new FontData[0];
	PangoFontFamily* family;
	PangoFontFace * face;
	PangoFontFamily** families;
	int n_families;
	PangoFontFace ** faces;
	int n_faces;
	auto context = OS.gdk_pango_context_get();
	OS.pango_context_list_families(context, &families, &n_families);
	int nFds = 0;
	FontData[] fds = new FontData[faceName !is null ? 4 : n_families];
	for (int i=0; i<n_families; i++) {
		family = families[i];
		bool match = true;
		if (faceName !is null) {
			auto familyName = OS.pango_font_family_get_name(family);
			match = Compatibility.equalsIgnoreCase(faceName, fromUtf8z( familyName ));
		}
		if (match) {
		    OS.pango_font_family_list_faces(family, &faces, &n_faces);
		    for (int j=0; j<n_faces; j++) {
		        face = faces[j];
		        auto fontDesc = OS.pango_font_face_describe(face);
		        Font font = Font.gtk_new(this, fontDesc);
		        FontData data = font.getFontData()[0];
				if (nFds is fds.length) {
                    FontData[] newFds = new FontData[fds.length + n_families];
                    System.arraycopy(fds, 0, newFds, 0, nFds);
                    fds = newFds;
				}
				fds[nFds++] = data;
				OS.pango_font_description_free(fontDesc);
		    }
		    OS.g_free(faces[0]);
		    if (faceName !is null) break;
		}
	}
	OS.g_free(families);
	OS.g_object_unref(context);
	if (nFds is fds.length) return fds;
    FontData[] result = new FontData[nFds];
    System.arraycopy(fds, 0, result, 0, nFds);
    return result;
}

/**
 * Returns the matching standard color for the given
 * constant, which should be one of the color constants
 * specified in class <code>SWT</code>. Any value other
 * than one of the SWT color constants which is passed
 * in will result in the color black. This color should
 * not be freed because it was allocated by the system,
 * not the application.
 *
 * @param id the color constant
 * @return the matching color
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 *
 * @see SWT
 */
public Color getSystemColor (int id) {
	checkDevice ();
	switch (id) {
		case SWT.COLOR_BLACK: 				return COLOR_BLACK;
		case SWT.COLOR_DARK_RED: 			return COLOR_DARK_RED;
		case SWT.COLOR_DARK_GREEN:	 		return COLOR_DARK_GREEN;
		case SWT.COLOR_DARK_YELLOW: 		return COLOR_DARK_YELLOW;
		case SWT.COLOR_DARK_BLUE: 			return COLOR_DARK_BLUE;
		case SWT.COLOR_DARK_MAGENTA: 		return COLOR_DARK_MAGENTA;
		case SWT.COLOR_DARK_CYAN: 			return COLOR_DARK_CYAN;
		case SWT.COLOR_GRAY: 				return COLOR_GRAY;
		case SWT.COLOR_DARK_GRAY: 			return COLOR_DARK_GRAY;
		case SWT.COLOR_RED: 				return COLOR_RED;
		case SWT.COLOR_GREEN: 				return COLOR_GREEN;
		case SWT.COLOR_YELLOW: 				return COLOR_YELLOW;
		case SWT.COLOR_BLUE: 				return COLOR_BLUE;
		case SWT.COLOR_MAGENTA: 			return COLOR_MAGENTA;
		case SWT.COLOR_CYAN: 				return COLOR_CYAN;
		case SWT.COLOR_WHITE: 				return COLOR_WHITE;
	}
	return COLOR_BLACK;
}

/**
 * Returns a reasonable font for applications to use.
 * On some platforms, this will match the "default font"
 * or "system font" if such can be found.  This font
 * should not be freed because it was allocated by the
 * system, not the application.
 * <p>
 * Typically, applications which want the default look
 * should simply not set the font on the widgets they
 * create. Widgets are always created with the correct
 * default font for the class of user-interface component
 * they represent.
 * </p>
 *
 * @return a font
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public Font getSystemFont () {
	checkDevice ();
	return systemFont;
}

/**
 * Returns <code>true</code> if the underlying window system prints out
 * warning messages on the console, and <code>setWarnings</code>
 * had previously been called with <code>true</code>.
 *
 * @return <code>true</code>if warnings are being handled, and <code>false</code> otherwise
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public bool getWarnings () {
	checkDevice ();
	return warningLevel is 0;
}

/**
 * Initializes any internal resources needed by the
 * device.
 * <p>
 * This method is called after <code>create</code>.
 * </p><p>
 * If subclasses reimplement this method, they must
 * call the <code>super</code> implementation.
 * </p>
 *
 * @see #create
 */
protected void init () {
	if (xDisplay !is null) {
		int event_basep, error_basep;
		if (OS.XRenderQueryExtension (xDisplay, &event_basep, &error_basep)) {
			int major_version, minor_version;
			OS.XRenderQueryVersion (xDisplay, &major_version, &minor_version);
			useXRender = major_version > 0 || (major_version is 0 && minor_version >= 8);
		}
	}

	if (debugging) {
		if (xDisplay !is null) {
			/* Create the warning and error callbacks */
			synchronized (CREATE_LOCK) {
				int index = 0;
				while (index < Devices.length) {
					if (Devices [index] !is null) break;
					index++;
				}
				if (index is Devices.length) {
					OS.XSetErrorHandler ( & XErrorProcFunc );
					OS.XSetIOErrorHandler ( & XIOErrorProcFunc );
				}
			}
			OS.XSynchronize (xDisplay, true);
		}
	}

	/* Create GTK warnings and error callbacks */
	if (xDisplay !is null) {
		/* Set GTK warning and error handlers */
		if (debugging) {
			int flags = OS.G_LOG_LEVEL_MASK | OS.G_LOG_FLAG_FATAL | OS.G_LOG_FLAG_RECURSION;
			for (int i=0; i<log_domains.length; i++) {
				handler_ids [i] = OS.g_log_set_handler (toStringz(log_domains [i]), flags, & logFunction, cast(void*)this);
			}
		}
	}

    /* Create the standard colors */
	COLOR_BLACK = new Color (this, 0,0,0);
	COLOR_DARK_RED = new Color (this, 0x80,0,0);
	COLOR_DARK_GREEN = new Color (this, 0,0x80,0);
	COLOR_DARK_YELLOW = new Color (this, 0x80,0x80,0);
	COLOR_DARK_BLUE = new Color (this, 0,0,0x80);
	COLOR_DARK_MAGENTA = new Color (this, 0x80,0,0x80);
	COLOR_DARK_CYAN = new Color (this, 0,0x80,0x80);
	COLOR_GRAY = new Color (this, 0xC0,0xC0,0xC0);
	COLOR_DARK_GRAY = new Color (this, 0x80,0x80,0x80);
	COLOR_RED = new Color (this, 0xFF,0,0);
	COLOR_GREEN = new Color (this, 0,0xFF,0);
	COLOR_YELLOW = new Color (this, 0xFF,0xFF,0);
	COLOR_BLUE = new Color (this, 0,0,0xFF);
	COLOR_MAGENTA = new Color (this, 0xFF,0,0xFF);
	COLOR_CYAN = new Color (this, 0,0xFF,0xFF);
	COLOR_WHITE = new Color (this, 0xFF,0xFF,0xFF);

	emptyTab = OS.pango_tab_array_new(1, false);
	if (emptyTab is null) SWT.error(SWT.ERROR_NO_HANDLES);
	OS.pango_tab_array_set_tab(emptyTab, 0, OS.PANGO_TAB_LEFT, 1);

	shellHandle = OS.gtk_window_new(OS.GTK_WINDOW_TOPLEVEL);
	if (shellHandle is null) SWT.error(SWT.ERROR_NO_HANDLES);
	OS.gtk_widget_realize(shellHandle);
}

/**
 * Invokes platform specific functionality to allocate a new GC handle.
 * <p>
 * <b>IMPORTANT:</b> This method is <em>not</em> part of the public
 * API for <code>Device</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 data the platform specific GC data
 * @return the platform specific GC handle
 */
public abstract GdkGC* internal_new_GC (GCData data);

/**
 * Invokes platform specific functionality to dispose a GC handle.
 * <p>
 * <b>IMPORTANT:</b> This method is <em>not</em> part of the public
 * API for <code>Device</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 hDC the platform specific GC handle
 * @param data the platform specific GC data
 */
public abstract void internal_dispose_GC (GdkGC* handle, GCData data);

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

/**
 * Loads the font specified by a file.  The font will be
 * present in the list of fonts available to the application.
 *
 * @param path the font file path
 * @return whether the font was successfully loaded
 *
 * @exception SWTException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if path is null</li>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 *
 * @see Font
 *
 * @since 3.3
 */
public bool loadFont (char[] path) {
	checkDevice();
	if (path is null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
	return cast(bool) OS.FcConfigAppFontAddFile (null, toStringz(path));
}

private static extern(C) void logFunction (char* log_domain, int log_level, char* message, void* user_data) {
    Device dev = cast(Device)user_data;
	if (dev.warningLevel is 0) {
		if (DEBUG || dev.debugging) {
            foreach( msg; new TracedException ("") ){
                Stderr.formatln( "trc {}", msg );
            }
		}
		OS.g_log_default_handler (log_domain, log_level, message, user_data);
	}
	return 0;
}

void new_Object (Object object) {
	for (int i=0; i<objects.length; i++) {
		if (objects [i] is null) {
			objects [i] = object;
			errors [i] = new TracedException ("");
			return;
		}
	}
    Object [] newObjects = new Object [objects.length + 128];
    System.arraycopy (objects, 0, newObjects, 0, objects.length);
    newObjects [objects.length] = object;
    objects = newObjects;
    TracedException [] newErrors = new TracedException [errors.length + 128];
    System.arraycopy (errors, 0, newErrors, 0, errors.length);
    newErrors [errors.length] = new TracedException ("");
    errors = newErrors;
}

static synchronized void register (Device device) {
	for (int i=0; i<Devices.length; i++) {
		if (Devices [i] is null) {
			Devices [i] = device;
			return;
		}
	}
    Device [] newDevices = new Device [Devices.length + 4];
    System.arraycopy (Devices, 0, newDevices, 0, Devices.length);
    newDevices [Devices.length] = device;
    Devices = newDevices;
}

/**
 * Releases any internal resources back to the operating
 * system and clears all fields except the device handle.
 * <p>
 * When a device is destroyed, resources that were acquired
 * on behalf of the programmer need to be returned to the
 * operating system.  For example, if the device allocated a
 * font to be used as the system font, this font would be
 * freed in <code>release</code>.  Also,to assist the garbage
 * collector and minimize the amount of memory that is not
 * reclaimed when the programmer keeps a reference to a
 * disposed device, all fields except the handle are zero'd.
 * The handle is needed by <code>destroy</code>.
 * </p>
 * This method is called before <code>destroy</code>.
 * </p><p>
 * If subclasses reimplement this method, they must
 * call the <code>super</code> implementation.
 * </p>
 *
 * @see #dispose
 * @see #destroy
 */
protected void release () {
	if (shellHandle !is null) OS.gtk_widget_destroy(shellHandle);
	shellHandle = null;

	if (gdkColors !is null) {
		auto colormap = OS.gdk_colormap_get_system();
		for (int i = 0; i < gdkColors.length; i++) {
			GdkColor* color = gdkColors [i];
			if (color !is null) {
				while (colorRefCount [i] > 0) {
					OS.gdk_colormap_free_colors(colormap, color, 1);
					--colorRefCount [i];
				}
			}
		}
	}
	gdkColors = null;
	colorRefCount = null;
	COLOR_BLACK = COLOR_DARK_RED = COLOR_DARK_GREEN = COLOR_DARK_YELLOW = COLOR_DARK_BLUE =
	COLOR_DARK_MAGENTA = COLOR_DARK_CYAN = COLOR_GRAY = COLOR_DARK_GRAY = COLOR_RED =
	COLOR_GREEN = COLOR_YELLOW = COLOR_BLUE = COLOR_MAGENTA = COLOR_CYAN = COLOR_WHITE = null;

	if (emptyTab !is null ) OS.pango_tab_array_free(emptyTab);
	emptyTab = null;

	/* Free the GTK error and warning handler */
	if (xDisplay !is null) {
		for (int i=0; i<handler_ids.length; i++) {
			if (handler_ids [i] !is 0 ) {
				OS.g_log_remove_handler (toStringz(log_domains [i]), handler_ids [i]);
				handler_ids [i] = 0;
			}
		}
		//logCallback.dispose ();  logCallback = null;
		handler_ids = null;  log_domains = null;
		//logProcFld = 0;
	}
}

/**
 * If the underlying window system supports printing warning messages
 * to the console, setting warnings to <code>false</code> prevents these
 * messages from being printed. If the argument is <code>true</code> then
 * message printing is not blocked.
 *
 * @param warnings <code>true</code>if warnings should be printed, and <code>false</code> otherwise
 *
 * @exception SWTException <ul>
 *    <li>ERROR_DEVICE_DISPOSED - if the receiver has been disposed</li>
 * </ul>
 */
public void setWarnings (bool warnings) {
	checkDevice ();
	if (warnings) {
		if (--warningLevel is 0) {
			if (debugging) return;
            for (int i=0; i<handler_ids.length; i++) {
                if (handler_ids [i] !is 0) {
                    OS.g_log_remove_handler (toStringz(log_domains [i]), handler_ids [i]);
                    handler_ids [i] = 0;
                }
            }
		}
	} else {
		if (warningLevel++ is 0) {
			if (debugging) return;
            int flags = OS.G_LOG_LEVEL_MASK | OS.G_LOG_FLAG_FATAL | OS.G_LOG_FLAG_RECURSION;
            for (int i=0; i<log_domains.length; i++) {
                handler_ids [i] = OS.g_log_set_handler (toStringz(log_domains [i]), flags, & logFunction, cast(void*)this );
            }
		}
	}
}

private static extern(C) int /*long*/ XErrorProcFunc (void* xDisplay, dwt.internal.gtk.OS.XErrorEvent* xErrorEvent) {
	Device device = findDevice (xDisplay);
	if (device !is null) {
		if (device.warningLevel is 0) {
			if (DEBUG || device.debugging) {
                foreach( msg; new TracedException ("") ){
                    Stderr.formatln( "trc {}", msg );
                }
			}
            //PORTING_FIXME ??
			//OS.Call (XErrorProc, xDisplay, xErrorEvent);
		}
	} else {
		if (DEBUG) (new SWTError ()).printStackTrace ();
        //PORTING_FIXME ??
		//OS.Call (XErrorProc, xDisplay, xErrorEvent);
	}
	return 0;
}

private static extern(C)  int /*long*/ XIOErrorProcFunc (void* xDisplay) {
	Device device = findDevice (xDisplay);
	if (device !is null) {
		if (DEBUG || device.debugging) {
            foreach( msg; new TracedException ("") ){
                Stderr.formatln( "trc {}", msg );
            }
		}
	} else {
		if (DEBUG) {
            foreach( msg; new TracedException ("") ){
                Stderr.formatln( "trc {}", msg );
            }
        }
	}
    //PORTING_FIXME ??
	//OS.Call (XIOErrorProc, xDisplay, 0);
	return 0;
}

}