#include "WINGsP.h"

#define XDND_SOURCE_VERSION(dragInfo) dragInfo->protocolVersion
#define XDND_DEST_INFO(dragInfo) dragInfo->destInfo
#define XDND_DEST_VIEW(dragInfo) dragInfo->destInfo->destView

static Bool _WindowExists;

Atom W_OperationToAction(WMScreen * scr, WMDragOperationType operation)
{
	switch (operation) {
	case WDOperationNone:
		return None;

	case WDOperationCopy:
		return scr->xdndActionCopy;

	case WDOperationMove:
		return scr->xdndActionMove;

	case WDOperationLink:
		return scr->xdndActionLink;

	case WDOperationAsk:
		return scr->xdndActionAsk;

	case WDOperationPrivate:
		return scr->xdndActionPrivate;

	default:
		return None;
	}
}

WMDragOperationType W_ActionToOperation(WMScreen * scr, Atom action)
{
	if (action == scr->xdndActionCopy) {
		return WDOperationCopy;

	} else if (action == scr->xdndActionMove) {
		return WDOperationMove;

	} else if (action == scr->xdndActionLink) {
		return WDOperationLink;

	} else if (action == scr->xdndActionAsk) {
		return WDOperationAsk;

	} else if (action == scr->xdndActionPrivate) {
		return WDOperationPrivate;

	} else if (action == None) {

		return WDOperationNone;
	} else {
		char *tmp = XGetAtomName(scr->display, action);

		wwarning("unknown XDND action %s ", tmp);
		XFree(tmp);

		return WDOperationCopy;
	}
}

static void freeDragOperationItem(void *item)
{
	wfree(item);
}

WMArray *WMCreateDragOperationArray(int initialSize)
{
	return WMCreateArrayWithDestructor(initialSize, freeDragOperationItem);
}

WMDragOperationItem *WMCreateDragOperationItem(WMDragOperationType type, char *text)
{
	W_DragOperationItem *result = wmalloc(sizeof(W_DragOperationItem));

	result->type = type;
	result->text = text;

	return (WMDragOperationItem *) result;
}

WMDragOperationType WMGetDragOperationItemType(WMDragOperationItem * item)
{
	return ((W_DragOperationItem *) item)->type;
}

char *WMGetDragOperationItemText(WMDragOperationItem * item)
{
	return ((W_DragOperationItem *) item)->text;
}

static int handleNoWindowXError(Display * dpy, XErrorEvent * errEvt)
{
	/* Parameter not used, but tell the compiler that it is ok */
	(void) dpy;

	if (errEvt->error_code == BadWindow || errEvt->error_code == BadDrawable) {
		_WindowExists = False;
		return Success;
	}

	return errEvt->error_code;
}

static Bool windowExists(Display * dpy, Window win)
{
	void *previousErrorHandler;
	XWindowAttributes attr;

	XSynchronize(dpy, True);
	previousErrorHandler = XSetErrorHandler(handleNoWindowXError);
	_WindowExists = True;

	/* can generate BadDrawable or BadWindow */
	XGetWindowAttributes(dpy, win, &attr);

	XSetErrorHandler(previousErrorHandler);
	XSynchronize(dpy, False);
	return _WindowExists;
}

Bool
W_SendDnDClientMessage(Display * dpy, Window win, Atom message,
		       unsigned long data0,
		       unsigned long data1, unsigned long data2, unsigned long data3, unsigned long data4)
{
	XEvent ev;

#ifdef XDND_DEBUG
	char *msgName = XGetAtomName(dpy, message);

	printf("sending message %s ... ", msgName);
	XFree(msgName);
#endif

	if (!windowExists(dpy, win)) {
		wwarning("xdnd message target %lu does no longer exist.", win);
		return False;	/* message not sent */
	}

	ev.type = ClientMessage;
	ev.xclient.message_type = message;
	ev.xclient.format = 32;
	ev.xclient.window = win;
	ev.xclient.data.l[0] = data0;
	ev.xclient.data.l[1] = data1;
	ev.xclient.data.l[2] = data2;
	ev.xclient.data.l[3] = data3;
	ev.xclient.data.l[4] = data4;

	XSendEvent(dpy, win, False, 0, &ev);
	XFlush(dpy);

#ifdef XDND_DEBUG
	printf("sent\n");
#endif
	return True;		/* message sent */
}

static void handleLeaveMessage(WMDraggingInfo * info)
{
	if (XDND_DEST_INFO(info) != NULL) {
		/* XDND_DEST_VIEW is never NULL (it's the xdnd aware view) */
		wassertr(XDND_DEST_VIEW(info) != NULL);
		if (XDND_DEST_VIEW(info)->dragDestinationProcs != NULL) {
			XDND_DEST_VIEW(info)->dragDestinationProcs->concludeDragOperation(XDND_DEST_VIEW(info));
		}
		W_DragDestinationInfoClear(info);
	}
}

void W_HandleDNDClientMessage(WMView * toplevel, XClientMessageEvent * event)
{
	WMScreen *scr = W_VIEW_SCREEN(toplevel);
	WMDraggingInfo *info = &scr->dragInfo;
	Atom messageType = event->message_type;

#ifdef XDND_DEBUG
	{
		char *msgTypeName = XGetAtomName(scr->display, messageType);

		if (msgTypeName != NULL)
			printf("event type = %s\n", msgTypeName);
		else
			printf("pb with event type !\n");
	}
#endif

	/* Messages from destination to source */
	if (messageType == scr->xdndStatusAtom || messageType == scr->xdndFinishedAtom) {
		W_DragSourceStopTimer();
		W_DragSourceStateHandler(info, event);
		return;
	}

	/* Messages from source to destination */
	if (messageType == scr->xdndEnterAtom) {
		Bool positionSent = (XDND_DEST_INFO(info) != NULL);

		W_DragDestinationStopTimer();
		W_DragDestinationStoreEnterMsgInfo(info, toplevel, event);

		/* Xdnd version 3 and up are not compatible with version 1 or 2 */
		if (XDND_SOURCE_VERSION(info) > 2) {

			if (positionSent) {
				/* xdndPosition previously received on xdnd aware view */
				W_DragDestinationStateHandler(info, event);
				return;
			} else {
				W_DragDestinationStartTimer(info);
				return;
			}
		} else {
			wwarning("received dnd enter msg with unsupported version %i", XDND_SOURCE_VERSION(info));
			W_DragDestinationCancelDropOnEnter(toplevel, info);
			return;
		}
	}

	if (messageType == scr->xdndPositionAtom) {
		W_DragDestinationStopTimer();
		W_DragDestinationStorePositionMsgInfo(info, toplevel, event);
		W_DragDestinationStateHandler(info, event);
		return;
	}

	if (messageType == scr->xdndSelectionAtom || messageType == scr->xdndDropAtom) {
		W_DragDestinationStopTimer();
		W_DragDestinationStateHandler(info, event);
		return;
	}

	if (messageType == scr->xdndLeaveAtom) {
		/* conclude drop operation, and clear dragging info */
		W_DragDestinationStopTimer();
		handleLeaveMessage(info);
	}
}

/* called in destroyView (wview.c) */
void W_FreeViewXdndPart(WMView * view)
{
	WMUnregisterViewDraggedTypes(view);

	if (view->dragSourceProcs)
		wfree(view->dragSourceProcs);

	if (view->dragDestinationProcs)
		wfree(view->dragDestinationProcs);

	if (view->dragImage)
		WMReleasePixmap(view->dragImage);
}