/*
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * Give credit where credit is due, keep the authors message below.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors:
 *   - Diogo Ferreira (playerX) <diogo@beryl-project.org>
 *   - Danny Baumann <maniac@beryl-project.org>
 *
 *
 * Copyright (c) 2007 Diogo "playerX" Ferreira
 *
 * This wouldn't have been possible without:
 *   - Ideas from the compiz community (mainly throughnothing's)
 *   - David Reveman's work
 *
 * */

#include <stdlib.h>
#include <string.h>

#include <compiz.h>
#include "showdesktop_options.h"

#include <math.h>

#define WIN_X(w) ((w)->attrib.x - (w)->input.left)
#define WIN_Y(w) ((w)->attrib.y - (w)->input.top)
#define WIN_W(w) ((w)->width + (w)->input.left + (w)->input.right)
#define WIN_H(w) ((w)->height + (w)->input.top + (w)->input.bottom)

#define OFF_LEFT(w) ((w)->width + (w)->input.right)
#define OFF_RIGHT(w) ((w)->input.left)
#define OFF_TOP(w) ((w)->height + (w)->input.bottom)
#define OFF_BOTTOM(w) ((w)->input.top)

#define MOVE_LEFT(w) ((WIN_X(w) + (WIN_W(w)/2)) < ((w)->screen->width/2))
#define MOVE_UP(w) ((WIN_Y(w) + (WIN_H(w)/2)) < ((w)->screen->height/2))

#define SD_STATE_OFF          0
#define SD_STATE_ACTIVATING   1
#define SD_STATE_ON           2
#define SD_STATE_DEACTIVATING 3

/* necessary plugin structs */
typedef struct _ShowdesktopPlacer
{
    int placed;
    int onScreenX, onScreenY;
    int offScreenX, offScreenY;
    int origViewportX;
    int origViewportY;
} ShowdesktopPlacer;

typedef struct _ShowdesktopDisplay
{
    int screenPrivateIndex;

    HandleEventProc handleEvent;
} ShowdesktopDisplay;

typedef struct _ShowdesktopScreen
{
    int windowPrivateIndex;

    PreparePaintScreenProc         preparePaintScreen;
    PaintOutputProc                paintOutput;
    DonePaintScreenProc            donePaintScreen;
    PaintWindowProc                paintWindow;
    EnterShowDesktopModeProc       enterShowDesktopMode;
    LeaveShowDesktopModeProc       leaveShowDesktopMode;
    GetAllowedActionsForWindowProc getAllowedActionsForWindow;
    FocusWindowProc                focusWindow;

    int state;
    int moreAdjust;
} ShowdesktopScreen;

typedef struct _ShowdesktopWindow
{
    int sid;
    int distance;

    ShowdesktopPlacer *placer;

    GLfloat xVelocity, yVelocity;
    GLfloat tx, ty;

    unsigned int notAllowedMask;
    unsigned int stateMask;
    Bool         showdesktoped;
    Bool         wasManaged;

    float delta;
    Bool adjust;
} ShowdesktopWindow;

/* shortcut macros, usually named X_DISPLAY, X_SCREEN and X_WINDOW
 * these might seem overly complicated but they are shortcuts so we don't have to access the privates arrays all the time
 * */
#define GET_SHOWDESKTOP_DISPLAY(d)				     \
    ((ShowdesktopDisplay *) (d)->privates[displayPrivateIndex].ptr)

#define SD_DISPLAY(d)			   \
    ShowdesktopDisplay *sd = GET_SHOWDESKTOP_DISPLAY (d)

#define GET_SHOWDESKTOP_SCREEN(s, sd)					 \
    ((ShowdesktopScreen *) (s)->privates[(sd)->screenPrivateIndex].ptr)

#define SD_SCREEN(s)							\
    ShowdesktopScreen *ss = GET_SHOWDESKTOP_SCREEN (s, GET_SHOWDESKTOP_DISPLAY (s->display))

#define GET_SHOWDESKTOP_WINDOW(w, ss)					  \
    ((ShowdesktopWindow *) (w)->privates[(ss)->windowPrivateIndex].ptr)

#define SD_WINDOW(w)					       \
    ShowdesktopWindow *sw = GET_SHOWDESKTOP_WINDOW  (w,		       \
			    GET_SHOWDESKTOP_SCREEN  (w->screen,        \
                            GET_SHOWDESKTOP_DISPLAY (w->screen->display)))

/* plugin private index */
static int displayPrivateIndex;

/* non interfacing code, aka the logic of the plugin */
static Bool
isSDWin (CompWindow *w)
{
    if (!(*w->screen->focusWindow) (w))
	return FALSE;

    if (!matchEval (showdesktopGetWindowMatch (w->screen), w))
	return FALSE;

    if (w->state & CompWindowStateSkipPagerMask)
	return FALSE;

    return TRUE;
}

static void
setSDWindowHints (CompWindow *w,
		  Bool       enterSDMode)
{
    unsigned int state = w->state;

    SD_WINDOW (w);

    sw->showdesktoped = enterSDMode;

    if (enterSDMode)
    {
	sw->stateMask = state & CompWindowStateSkipPagerMask;
	state |= CompWindowStateSkipPagerMask;
	sw->notAllowedMask = CompWindowActionMoveMask |
	                     CompWindowActionResizeMask;
    }
    else
    {
	state &= ~CompWindowStateSkipPagerMask;
	state |= (sw->stateMask & CompWindowStateSkipPagerMask);
	sw->notAllowedMask = 0;
    }

    changeWindowState (w, state);
    recalcWindowActions (w);

    if (enterSDMode)
    {
	sw->wasManaged = w->managed;
	w->managed = FALSE;
    }
    else
	w->managed = sw->wasManaged;
}

static void
repositionSDPlacer (CompWindow *w, 
		    int        oldState)
{
    CompScreen *s = w->screen;

    SD_WINDOW (w);

    if (!sw->placer)
	return;

    if (oldState == SD_STATE_OFF)
    {
	sw->placer->onScreenX = w->attrib.x;
	sw->placer->onScreenY = w->attrib.y;
	sw->placer->origViewportX = s->x;
	sw->placer->origViewportY = s->y;
    }

    switch (showdesktopGetDirection (w->screen))
    {
    case DirectionUp:
	sw->placer->offScreenX = w->attrib.x;
	sw->placer->offScreenY = s->workArea.y - OFF_TOP (w) +
	                         showdesktopGetWindowPartSize (s);
	break;
    case DirectionDown:
	sw->placer->offScreenX = w->attrib.x;
	sw->placer->offScreenY = s->workArea.y + 
	                         s->workArea.height + OFF_BOTTOM (w) - 
				 showdesktopGetWindowPartSize (s);
	break;
    case DirectionLeft:
	sw->placer->offScreenX = s->workArea.x - OFF_LEFT (w) +
	                         showdesktopGetWindowPartSize (s);
	sw->placer->offScreenY = w->attrib.y;
	break;
    case DirectionRight:
	sw->placer->offScreenX = s->workArea.x +
	                         s->workArea.width + OFF_RIGHT (w) -
				 showdesktopGetWindowPartSize (s);
	sw->placer->offScreenY = w->attrib.y;
	break;
    case DirectionUpDown:
	sw->placer->offScreenX = w->attrib.x;
	if (MOVE_UP (w))
    	    sw->placer->offScreenY = s->workArea.y - OFF_TOP (w) +
		                     showdesktopGetWindowPartSize (s);
	else
	    sw->placer->offScreenY = s->workArea.y +
		                     s->workArea.height + OFF_BOTTOM (w) -
				     showdesktopGetWindowPartSize (s);
	break;
    case DirectionLeftRight:
	sw->placer->offScreenY = w->attrib.y;
	if (MOVE_LEFT (w))
    	    sw->placer->offScreenX = s->workArea.x - OFF_LEFT (w) +
		                     showdesktopGetWindowPartSize (s);
	else
	    sw->placer->offScreenX = s->workArea.x +
		                     s->workArea.width + OFF_RIGHT (w) -
				     showdesktopGetWindowPartSize (s);
	break;
    case DirectionToCorners:
	if (MOVE_LEFT (w))
	    sw->placer->offScreenX = s->workArea.x - OFF_LEFT (w) +
		                     showdesktopGetWindowPartSize (s);
	else
	    sw->placer->offScreenX = s->workArea.x +
		                     s->workArea.width + OFF_RIGHT (w) -
				     showdesktopGetWindowPartSize (s);
	if (MOVE_UP(w))
	    sw->placer->offScreenY = s->workArea.y - OFF_TOP (w) +
		                     showdesktopGetWindowPartSize (s);
	else
	    sw->placer->offScreenY = s->workArea.y +
		                     s->workArea.height + OFF_BOTTOM (w) -
		     		     showdesktopGetWindowPartSize (s);
	break;
    default:
	break;
    }
}

static int
prepareSDWindows (CompScreen *s,
		  int        oldState)
{
    CompWindow *w;
    int        count = 0;

    for (w = s->windows; w; w = w->next)
    {
	SD_WINDOW (w);

	if (!isSDWin (w))
	    continue;

	if (!sw->placer)
	    sw->placer = malloc (sizeof (ShowdesktopPlacer));

	if (!sw->placer)
	    continue;

	repositionSDPlacer (w, oldState);

	sw->placer->placed   = TRUE;
	sw->adjust           = TRUE;
	w->inShowDesktopMode = TRUE;

	setSDWindowHints (w, TRUE);

	if (sw->tx)
	    sw->tx -= (sw->placer->onScreenX - sw->placer->offScreenX);
	if (sw->ty)
	    sw->ty -= (sw->placer->onScreenY - sw->placer->offScreenY);

	moveWindow (w,
		    sw->placer->offScreenX - w->attrib.x,
		    sw->placer->offScreenY - w->attrib.y,
		    TRUE, TRUE);
	syncWindowPosition (w);

	count++;
    }

    return count;
}

/* plugin initialization */

static Bool
showdesktopInit (CompPlugin *p)
{
    displayPrivateIndex = allocateDisplayPrivateIndex ();

    if (displayPrivateIndex < 0)
	return FALSE;

    return TRUE;
}

/* plugin finalization */
static void
showdesktopFini (CompPlugin *p)
{
    freeDisplayPrivateIndex (displayPrivateIndex);
}

/* adjust velocity for each animation step (adapted from the scale plugin) */
static int
adjustSDVelocity (CompWindow *w)
{
    float dx, dy, adjust, amount;
    float x1, y1;
    float baseX, baseY;

    SD_WINDOW (w);
    SD_SCREEN (w->screen);

    x1 = y1 = 0.0;

    if (ss->state == SD_STATE_ACTIVATING)
    {
	x1 = sw->placer->offScreenX;
	y1 = sw->placer->offScreenY;
	baseX = sw->placer->onScreenX;
	baseY = sw->placer->onScreenY;
    }
    else
    {
	x1 = sw->placer->onScreenX;
	y1 = sw->placer->onScreenY;
	baseX = sw->placer->offScreenX;
	baseY = sw->placer->offScreenY;
    }

    dx = x1 - (baseX + sw->tx);

    adjust = dx * 0.15f;
    amount = fabs (dx) * 1.5f;
    if (amount < 0.5f)
	amount = 0.5f;
    else if (amount > 5.0f)
	amount = 5.0f;

    sw->xVelocity = (amount * sw->xVelocity + adjust) / (amount + 1.0f);

    dy = y1 - (baseY + sw->ty);

    adjust = dy * 0.15f;
    amount = fabs (dy) * 1.5f;
    if (amount < 0.5f)
	amount = 0.5f;
    else if (amount > 5.0f)
	amount = 5.0f;

    sw->yVelocity = (amount * sw->yVelocity + adjust) / (amount + 1.0f);

    if (fabs (dx) < 0.1f && fabs (sw->xVelocity) < 0.2f &&
	fabs (dy) < 0.1f && fabs (sw->yVelocity) < 0.2f)
    {
	sw->xVelocity = sw->yVelocity = 0.0f;
	sw->tx = x1 - baseX;
	sw->ty = y1 - baseY;

	return 0;
    }
    return 1;
}

/* this function gets called periodically (about every 15ms on this machine),
 * animation takes place here */
static void
showdesktopPreparePaintScreen (CompScreen *s,
			       int        msSinceLastPaint)
{
    SD_SCREEN (s);

    UNWRAP (ss, s, preparePaintScreen);
    (*s->preparePaintScreen) (s, msSinceLastPaint);
    WRAP (ss, s, preparePaintScreen, showdesktopPreparePaintScreen);

    if ((ss->state == SD_STATE_ACTIVATING) ||
	(ss->state == SD_STATE_DEACTIVATING))
    {
	CompWindow *w;
	int        steps;
	float      amount, chunk;

	amount = msSinceLastPaint * 0.05f * showdesktopGetSpeed (s);
	steps = amount / (0.5f * showdesktopGetTimestep (s));
	if (!steps)
    	    steps = 1;
	chunk = amount / (float)steps;

	while (steps--)
	{
	    ss->moreAdjust = 0;

	    for (w = s->windows; w; w = w->next)
	    {
		SD_WINDOW (w);

		if (sw->adjust)
		{
		    sw->adjust = adjustSDVelocity (w);

		    ss->moreAdjust |= sw->adjust;

    		    sw->tx += sw->xVelocity * chunk;
		    sw->ty += sw->yVelocity * chunk;
		}
	    }
	    if (!ss->moreAdjust)
		break;
	}
    }
}

static Bool
showdesktopPaintOutput (CompScreen              *s,
			const ScreenPaintAttrib *sAttrib,
			const CompTransform     *transform,
			Region                  region,
			CompOutput              *output,
			unsigned int            mask)
{
    Bool status;

    SD_SCREEN (s);

    if ((ss->state == SD_STATE_ACTIVATING) ||
	(ss->state == SD_STATE_DEACTIVATING))
    {
	mask |= PAINT_SCREEN_WITH_TRANSFORMED_WINDOWS_MASK;
    }

    UNWRAP (ss, s, paintOutput);
    status = (*s->paintOutput) (s, sAttrib, transform, region, output, mask);
    WRAP (ss, s, paintOutput, showdesktopPaintOutput);

    return status;
}

/* this one gets called after the one above and periodically,
 * here the plugin checks if windows reached the end */
static void
showdesktopDonePaintScreen (CompScreen *s)
{
    SD_SCREEN (s);

    if (ss->moreAdjust)
    {
	damageScreen (s);
    }
    else
    {
	if ((ss->state == SD_STATE_ACTIVATING) ||
	    (ss->state == SD_STATE_DEACTIVATING))
	{
	    CompWindow *w;
	    if (ss->state == SD_STATE_ACTIVATING)
	    {
		ss->state = SD_STATE_ON;
	    }
	    else
    	    {
		Bool inSDMode = FALSE;

		for (w = s->windows; w; w = w->next)
		{
		    if (w->inShowDesktopMode)
			inSDMode = TRUE;
		    else
		    {
			SD_WINDOW (w);
			if (sw->placer)
			{
			    free (sw->placer);
			    sw->placer = NULL;
			}
		    }
		}

		if (inSDMode)
		    ss->state = SD_STATE_ON;
		else
		    ss->state = SD_STATE_OFF;
	    }

	    damageScreen (s);
	}
    }

    UNWRAP (ss, s, donePaintScreen);
    (*s->donePaintScreen) (s);
    WRAP (ss, s, donePaintScreen, showdesktopDonePaintScreen);
}

static Bool
showdesktopPaintWindow (CompWindow              *w,
			const WindowPaintAttrib *attrib,
			const CompTransform     *transform,
			Region                  region,
			unsigned int            mask)
{
    CompScreen *s = w->screen;
    Bool       status;

    SD_SCREEN (s);

    if ((ss->state == SD_STATE_ACTIVATING) ||
	(ss->state == SD_STATE_DEACTIVATING))
    {
	SD_WINDOW (w);

	CompTransform     wTransform = *transform;
	WindowPaintAttrib wAttrib    = *attrib;

	if (sw->adjust)
	{
	    float offsetX, offsetY;

	    offsetX = (ss->state == SD_STATE_DEACTIVATING) ?
		      (sw->placer->offScreenX - sw->placer->onScreenX) :
		      (sw->placer->onScreenX - sw->placer->offScreenX);
	    offsetY = (ss->state == SD_STATE_DEACTIVATING) ?
		      (sw->placer->offScreenY - sw->placer->onScreenY) :
		      (sw->placer->onScreenY - sw->placer->offScreenY);

	    mask |= PAINT_WINDOW_TRANSFORMED_MASK;

	    matrixTranslate (&wTransform, w->attrib.x, w->attrib.y, 0.0f);
	    matrixScale (&wTransform, 1.0f, 1.0f, 1.0f);
	    matrixTranslate (&wTransform,
			     sw->tx + offsetX - w->attrib.x,
			     sw->ty + offsetY - w->attrib.y, 0.0f);
	}

	UNWRAP (ss, s, paintWindow);
	status = (*s->paintWindow) (w, &wAttrib, &wTransform, region, mask);
	WRAP (ss, s, paintWindow, showdesktopPaintWindow);
    }
    else if (ss->state == SD_STATE_ON)
    {
	WindowPaintAttrib wAttrib = *attrib;

	if (w->inShowDesktopMode)
	    wAttrib.opacity = wAttrib.opacity *
		              showdesktopGetWindowOpacity (s);

	UNWRAP (ss, s, paintWindow);
	status = (*s->paintWindow) (w, &wAttrib, transform, region, mask);
	WRAP (ss, s, paintWindow, showdesktopPaintWindow);
    }
    else
    {
	UNWRAP (ss, s, paintWindow);
	status = (*s->paintWindow) (w, attrib, transform, region, mask);
	WRAP (ss, s, paintWindow, showdesktopPaintWindow);
    }

    return status;
}

static void
showdesktopHandleEvent (CompDisplay *d,
			XEvent      *event)
{
    SD_DISPLAY (d);

    switch (event->type)
    {
    case PropertyNotify:
	if (event->xproperty.atom == d->desktopViewportAtom)
	{
	    CompScreen *s = findScreenAtDisplay (d, event->xproperty.window);
	    if (s)
	    {
		SD_SCREEN (s);

		if ((ss->state == SD_STATE_ON) ||
		    (ss->state == SD_STATE_ACTIVATING))
		{
		    (*s->leaveShowDesktopMode)(s, NULL);
		}
	    }
	}
	break;
    }

    UNWRAP (sd, d, handleEvent);
    (*d->handleEvent) (d, event);
    WRAP (sd, d, handleEvent, showdesktopHandleEvent);
}

static void
showdesktopGetAllowedActionsForWindow (CompWindow   *w,
				       unsigned int *setActions,
				       unsigned int *clearActions)
{
    CompScreen   *s = w->screen;

    SD_SCREEN (s);
    SD_WINDOW (w);

    UNWRAP (ss, s, getAllowedActionsForWindow);
    (*s->getAllowedActionsForWindow) (w, setActions, clearActions);
    WRAP (ss, s, getAllowedActionsForWindow,
	  showdesktopGetAllowedActionsForWindow);

    *clearActions |= sw->notAllowedMask;
}

static void
showdesktopEnterShowDesktopMode (CompScreen *s)
{
    int count = 0;

    SD_SCREEN (s);

    if (ss->state == SD_STATE_OFF || ss->state == SD_STATE_DEACTIVATING)
    {
	count = prepareSDWindows (s, ss->state);
	if (count > 0)
	{
	    XSetInputFocus (s->display->display, s->root,
			    RevertToPointerRoot, CurrentTime);
	    ss->state = SD_STATE_ACTIVATING;
	    damageScreen (s);
	}
    }

    UNWRAP (ss, s, enterShowDesktopMode);
    (*s->enterShowDesktopMode) (s);
    WRAP (ss, s, enterShowDesktopMode, showdesktopEnterShowDesktopMode);
}

static void
showdesktopLeaveShowDesktopMode (CompScreen *s,
				 CompWindow *w)
{
    SD_SCREEN (s);

    if (ss->state != SD_STATE_OFF)
    {
	CompWindow *cw;

	for (cw = s->windows; cw; cw = cw->next)
	{
	    SD_WINDOW (cw);

    	    if (w && (w->id != cw->id))
		continue;

	    if (sw->placer && sw->placer->placed)
	    {
		sw->adjust         = TRUE;
		sw->placer->placed = FALSE;

		/* adjust onscreen position to handle viewport changes  */
		sw->tx += (sw->placer->onScreenX - sw->placer->offScreenX);
		sw->ty += (sw->placer->onScreenY - sw->placer->offScreenY);

		sw->placer->onScreenX += (sw->placer->origViewportX -
					  cw->screen->x) * cw->screen->width;
		sw->placer->onScreenY += (sw->placer->origViewportY -
					  cw->screen->y) * cw->screen->height;

		moveWindow (cw,
			    sw->placer->onScreenX - cw->attrib.x,
			    sw->placer->onScreenY - cw->attrib.y, 
			    TRUE, TRUE);
		syncWindowPosition (cw);
		
		setSDWindowHints (cw, FALSE);
		cw->inShowDesktopMode = FALSE;
	    }
	}
	ss->state = SD_STATE_DEACTIVATING;
	damageScreen (s);
    }

    UNWRAP (ss, s, leaveShowDesktopMode);
    (*s->leaveShowDesktopMode) (s, w);
    WRAP (ss, s, leaveShowDesktopMode, showdesktopLeaveShowDesktopMode);
}

static Bool
showdesktopFocusWindow (CompWindow *w)
{
    CompScreen *s = w->screen;
    Bool       ret;

    SD_SCREEN (s);
    SD_WINDOW (w);

    if (sw->showdesktoped)
	w->managed = sw->wasManaged;

    UNWRAP (ss, s, focusWindow);
    ret = (*s->focusWindow) (w);
    WRAP (ss, s, focusWindow, showdesktopFocusWindow);

    if (sw->showdesktoped)
	w->managed = FALSE;

    return ret;
}

/* display initialization */

static Bool
showdesktopInitDisplay (CompPlugin  *p,
			CompDisplay *d)
{
    ShowdesktopDisplay *sd;

    sd = malloc (sizeof (ShowdesktopDisplay));
    if (!sd)
	return FALSE;

    sd->screenPrivateIndex = allocateScreenPrivateIndex (d);
    if (sd->screenPrivateIndex < 0)
    {
	free (sd);
	return FALSE;
    }

    WRAP (sd, d, handleEvent, showdesktopHandleEvent);

    d->privates[displayPrivateIndex].ptr = sd;

    return TRUE;
}

static void
showdesktopFiniDisplay (CompPlugin  *p,
			CompDisplay *d)
{
    SD_DISPLAY (d);

    freeScreenPrivateIndex (d, sd->screenPrivateIndex);

    UNWRAP (sd, d, handleEvent);

    free (sd);
}

static Bool
showdesktopInitScreen (CompPlugin *p,
		       CompScreen *s)
{
    ShowdesktopScreen *ss;

    SD_DISPLAY (s->display);

    ss = malloc (sizeof (ShowdesktopScreen));
    if (!ss)
	return FALSE;

    ss->windowPrivateIndex = allocateWindowPrivateIndex (s);
    if (ss->windowPrivateIndex < 0)
    {
	free (ss);
	return FALSE;
    }

    ss->state = SD_STATE_OFF;
    ss->moreAdjust = 0;

    WRAP (ss, s, preparePaintScreen, showdesktopPreparePaintScreen);
    WRAP (ss, s, paintOutput, showdesktopPaintOutput);
    WRAP (ss, s, donePaintScreen, showdesktopDonePaintScreen);
    WRAP (ss, s, paintWindow, showdesktopPaintWindow);
    WRAP (ss, s, enterShowDesktopMode, showdesktopEnterShowDesktopMode);
    WRAP (ss, s, leaveShowDesktopMode, showdesktopLeaveShowDesktopMode);
    WRAP (ss, s, focusWindow, showdesktopFocusWindow);
    WRAP (ss, s, getAllowedActionsForWindow,
	  showdesktopGetAllowedActionsForWindow);

    s->privates[sd->screenPrivateIndex].ptr = ss;

    return TRUE;
}

/* Free screen resources */
static void
showdesktopFiniScreen (CompPlugin *p,
		       CompScreen *s)
{
    SD_SCREEN (s);

    UNWRAP (ss, s, preparePaintScreen);
    UNWRAP (ss, s, paintOutput);
    UNWRAP (ss, s, donePaintScreen);
    UNWRAP (ss, s, paintWindow);
    UNWRAP (ss, s, enterShowDesktopMode);
    UNWRAP (ss, s, leaveShowDesktopMode);
    UNWRAP (ss, s, focusWindow);
    UNWRAP (ss, s, getAllowedActionsForWindow);

    freeWindowPrivateIndex (s, ss->windowPrivateIndex);

    free (ss);
}

/* window init */
static Bool
showdesktopInitWindow (CompPlugin *p,
		       CompWindow *w)
{
    ShowdesktopWindow *sw;

    SD_SCREEN (w->screen);

    sw = malloc (sizeof (ShowdesktopWindow));
    if (!sw)
	return FALSE;

    sw->showdesktoped = FALSE;
    sw->adjust = FALSE;
    sw->delta  = 1.0f;
    sw->placer = NULL;

    sw->tx = sw->ty = 0.0f;
    sw->xVelocity = sw->yVelocity = 0.0f;

    sw->stateMask      = 0;
    sw->notAllowedMask = 0;

    w->privates[ss->windowPrivateIndex].ptr = sw;

    return TRUE;
}

/* Free window resources */
static void
showdesktopFiniWindow (CompPlugin *p,
		       CompWindow *w)
{
    SD_WINDOW (w);

    free (sw);
}

static int
showdesktopGetVersion (CompPlugin *plugin,
		       int        version)
{
    return ABIVERSION;
}

/* plugin vtable */
static CompPluginVTable showdesktopVTable = {
    "showdesktop",
    showdesktopGetVersion,
    0,
    showdesktopInit,
    showdesktopFini,
    showdesktopInitDisplay,
    showdesktopFiniDisplay,
    showdesktopInitScreen,
    showdesktopFiniScreen,
    showdesktopInitWindow,
    showdesktopFiniWindow,
    NULL,
    NULL,
    NULL,
    NULL
};

/* send plugin info */
CompPluginVTable *
getCompPluginInfo (void)
{
    return &showdesktopVTable;
}


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