package org.eclipse.swt.widgets;

/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved
 */
 
import org.eclipse.swt.internal.motif.*;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.events.*;

/**
 * Instances of the receiver represent a selectable user interface object
 * that allows the user to drag a rubber banded outline of the sash within
 * the parent control.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd> HORIZONTAL, VERTICAL</dd>
 * <dt><b>Events:</b></dt>
 * <dd>Selection</dd>
 * </dl>
 * <p>
 * IMPORTANT: This class is intended to be subclassed <em>only</em>
 * within the SWT implementation.
 * </p>
 */

public /*final*/ class Sash extends Control {
	boolean dragging;
	int startX, startY, lastX, lastY;
	int cursor;
/**
 * 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
 * for all SWT widget classes should include a comment which
 * describes the style constants which are applicable to the class.
 * </p>
 *
 * @param parent a composite control which will be the parent of the new instance (cannot be null)
 * @param style the style of control 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>
 *
 * @see SWT
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public Sash (Composite parent, int style) {
	super (parent, checkStyle (style));
}
/**
 * Adds the listener to the collection of listeners who will
 * be notified when the control is selected, by sending
 * it one of the messages defined in the <code>SelectionListener</code>
 * interface.
 * <p>
 * When <code>widgetSelected</code> is called, the x, y, width, and height fields of the event object are valid.
 * If the reciever is being dragged, the event object detail field contains the value <code>SWT.DRAG</code>.
 * <code>widgetDefaultSelected</code> is not called.
 * </p>
 *
 * @param listener the listener which should be notified
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 *
 * @see SelectionListener
 * @see #removeSelectionListener
 * @see SelectionEvent
 */
public void addSelectionListener(SelectionListener listener) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener(listener);
	addListener(SWT.Selection,typedListener);
	addListener(SWT.DefaultSelection,typedListener);
}
static int checkStyle (int style) {
	return checkBits (style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0);
}
public Point computeSize (int wHint, int hHint, boolean changed) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	int border = getBorderWidth ();
	int width = border * 2, height = border * 2;
	if ((style & SWT.HORIZONTAL) != 0) {
		width += DEFAULT_WIDTH;  height += 3;
	} else {
		width += 3; height += DEFAULT_HEIGHT;
	}
	if (wHint != SWT.DEFAULT) width = wHint + (border * 2);
	if (hHint != SWT.DEFAULT) height = hHint + (border * 2);
	return new Point (width, height);
}
void createHandle (int index) {
	state |= HANDLE;
	int border = (style & SWT.BORDER) != 0 ? 1 : 0;
	int [] argList = {
		OS.XmNborderWidth, border,
		OS.XmNmarginWidth, 0,
		OS.XmNmarginHeight, 0,
		OS.XmNresizePolicy, OS.XmRESIZE_NONE,
		OS.XmNancestorSensitive, 1,
	};
	int parentHandle = parent.handle;
	handle = OS.XmCreateDrawingArea (parentHandle, null, argList, argList.length / 2);
}
void drawBand (int x, int y, int width, int height) {
	int display = OS.XtDisplay (parent.handle);
	if (display == 0) return;
	int window = OS.XtWindow (parent.handle);
	if (window == 0) return;
	int [] argList = {OS.XmNforeground, 0, OS.XmNbackground, 0};
	OS.XtGetValues (parent.handle, argList, argList.length / 2);
	int color = argList [1] ^ argList [3];
	byte [] bits = {-86, 0, 85, 0, -86, 0, 85, 0, -86, 0, 85, 0, -86, 0, 85, 0};
	int stipplePixmap = OS.XCreateBitmapFromData (display, window, bits, 8, 8);
	int gc = OS.XCreateGC (display, window, 0, null);
	OS.XSetForeground (display, gc, color);
	OS.XSetStipple (display, gc, stipplePixmap);
	OS.XSetSubwindowMode (display, gc, OS.IncludeInferiors);
	OS.XSetFillStyle (display, gc, OS.FillStippled);
	OS.XSetFunction (display, gc, OS.GXxor);
	OS.XFillRectangle (display, window, gc, x, y, width, height);
	OS.XFreePixmap (display, stipplePixmap);
	OS.XFreeGC (display, gc);
}
int processMouseDown (int callData) {
	super.processMouseDown (callData);
	XButtonEvent xEvent = new XButtonEvent ();
	OS.memmove (xEvent, callData, XButtonEvent.sizeof);
	if (xEvent.button != 1) return 0;
	startX = xEvent.x;  startY = xEvent.y;
	int [] argList = {OS.XmNx, 0, OS.XmNy, 0, OS.XmNwidth, 0, OS.XmNheight, 0, OS.XmNborderWidth, 0};
	OS.XtGetValues (handle, argList, argList.length / 2);
	int border = argList [9], width = argList [5] + (border * 2), height = argList [7] + (border * 2);
	lastX = ((short) argList [1]) - border;  lastY = ((short) argList [3]) - border;
	Event event = new Event ();
	event.detail = SWT.DRAG;
	event.time = xEvent.time;
	event.x = lastX;  event.y = lastY;
	event.width = width;  event.height = height;
	sendEvent (SWT.Selection, event);
	if (event.doit) {
		dragging = true;
		OS.XmUpdateDisplay (handle);
		drawBand (lastX = event.x, lastY = event.y, width, height);
	}
	return 0;
}
int processMouseMove (int callData) {
	super.processMouseMove (callData);
	XMotionEvent xEvent = new XMotionEvent ();
	OS.memmove (xEvent, callData, XMotionEvent.sizeof);
	if (!dragging || (xEvent.state & OS.Button1Mask) == 0) return 0;
	int [] argList1 = {OS.XmNx, 0, OS.XmNy, 0, OS.XmNwidth, 0, OS.XmNheight, 0, OS.XmNborderWidth, 0};
	OS.XtGetValues (handle, argList1, argList1.length / 2);
	int border = argList1 [9], x = ((short) argList1 [1]) - border, y = ((short) argList1 [3]) - border;
	int width = argList1 [5] + (border * 2), height = argList1 [7] + (border * 2);
	int [] argList2 = {OS.XmNwidth, 0, OS.XmNheight, 0, OS.XmNborderWidth, 0};
	OS.XtGetValues (parent.handle, argList2, argList2.length / 2);
	int parentBorder = argList2 [5];
	int parentWidth = argList2 [1] + (parentBorder * 2);
	int parentHeight = argList2 [3] + (parentBorder * 2);
	int newX = lastX, newY = lastY;
	if ((style & SWT.VERTICAL) != 0) {
		newX = Math.min (Math.max (0, xEvent.x + x - startX - parentBorder), parentWidth - width);
	} else {
		newY = Math.min (Math.max (0, xEvent.y + y - startY - parentBorder), parentHeight - height);
	}
	if (newX == lastX && newY == lastY) return 0;
	drawBand (lastX, lastY, width, height);
	Event event = new Event ();
	event.detail = SWT.DRAG;
	event.time = xEvent.time;
	event.x = newX;  event.y = newY;
	event.width = width;  event.height = height;
	sendEvent (SWT.Selection, event);
	if (event.doit) {
		lastX = event.x;  lastY = event.y;
		OS.XmUpdateDisplay (handle);
		drawBand (lastX, lastY, width, height);
	}
	return 0;
}
int processMouseUp (int callData) {
	super.processMouseUp (callData);
	XButtonEvent xEvent = new XButtonEvent ();
	OS.memmove (xEvent, callData, XButtonEvent.sizeof);
	if (xEvent.button != 1) return 0;
	if (!dragging) return 0;
	dragging = false;
	int [] argList = {OS.XmNwidth, 0, OS.XmNheight, 0, OS.XmNborderWidth, 0};
	OS.XtGetValues (handle, argList, argList.length / 2);
	int border = argList [5];
	int width = argList [1] + (border * 2), height = argList [3] + (border * 2);
	Event event = new Event ();
	event.time = xEvent.time;
	event.x = lastX;  event.y = lastY;
	event.width = width;  event.height = height;
	drawBand (lastX, lastY, width, height);
	sendEvent (SWT.Selection, event);
	return 0;
}
void realizeChildren () {
	super.realizeChildren ();
	int window = OS.XtWindow (handle);
	if (window == 0) return;
	int display = OS.XtDisplay (handle);
	if (display == 0) return;
	if ((style & SWT.HORIZONTAL) != 0) {
		cursor = OS.XCreateFontCursor (display, OS.XC_sb_v_double_arrow);
	} else {
		cursor = OS.XCreateFontCursor (display, OS.XC_sb_h_double_arrow);
	}
	OS.XDefineCursor (display, window, cursor);
}
void releaseWidget () {
	super.releaseWidget ();
	if (cursor != 0) {
		int display = OS.XtDisplay (handle);
		if (display != 0) OS.XFreeCursor (display, cursor);
	}
	cursor = 0;
}
/**
 * Removes the listener from the collection of listeners who will
 * be notified when the control is selected.
 *
 * @param listener the listener which should be notified
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 *
 * @see SelectionListener
 * @see #addSelectionListener
 */
public void removeSelectionListener(SelectionListener listener) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook(SWT.Selection, listener);
	eventTable.unhook(SWT.DefaultSelection,listener);	
}
}