/*
 *
 * Copyright © 2002 Keith Packard, member of The XFree86 Project, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Keith Packard not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Keith Packard makes no
 * representations about the suitability of this software for any purpose.  It
 * is provided "as is" without express or implied warranty.
 *
 * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * Animated cursors for X.  Not specific to Render in any way, but
 * stuck there because Render has the other cool cursor extension.
 * Besides, everyone has Render.
 *
 * Implemented as a simple layer over the core cursor code; it
 * creates composite cursors out of a set of static cursors and
 * delta times between each image.
 */

#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif

#include <X11/X.h>
#include <X11/Xmd.h>
#include "servermd.h"
#include "scrnintstr.h"
#include "dixstruct.h"
#include "cursorstr.h"
#include "dixfontstr.h"
#include "opaque.h"
#include "picturestr.h"

typedef struct _AnimCurElt {
    CursorPtr pCursor;          /* cursor to show */
    CARD32 delay;               /* in ms */
} AnimCurElt;

typedef struct _AnimCur {
    int nelt;                   /* number of elements in the elts array */
    AnimCurElt *elts;           /* actually allocated right after the structure */
} AnimCurRec, *AnimCurPtr;

typedef struct _AnimScrPriv {
    CursorPtr pCursor;
    int elt;
    CARD32 time;

    CloseScreenProcPtr CloseScreen;

    ScreenBlockHandlerProcPtr BlockHandler;

    CursorLimitsProcPtr CursorLimits;
    DisplayCursorProcPtr DisplayCursor;
    SetCursorPositionProcPtr SetCursorPosition;
    RealizeCursorProcPtr RealizeCursor;
    UnrealizeCursorProcPtr UnrealizeCursor;
    RecolorCursorProcPtr RecolorCursor;
} AnimCurScreenRec, *AnimCurScreenPtr;

typedef struct _AnimCurState {
    CursorPtr pCursor;
    ScreenPtr pScreen;
    int elt;
    CARD32 time;
} AnimCurStateRec, *AnimCurStatePtr;

static AnimCurStateRec animCurState;

static unsigned char empty[4];

static CursorBits animCursorBits = {
    empty, empty, 2, 1, 1, 0, 0, 1
};

int AnimCurScreenPrivateIndex = -1;

int AnimCurGeneration;

#define IsAnimCur(c)	    ((c)->bits == &animCursorBits)
#define GetAnimCur(c)	    ((AnimCurPtr) ((c) + 1))
#define GetAnimCurScreen(s) ((AnimCurScreenPtr) ((s)->devPrivates[AnimCurScreenPrivateIndex].ptr))
#define GetAnimCurScreenIfSet(s) ((AnimCurScreenPrivateIndex != -1) ? GetAnimCurScreen(s) : NULL)
#define SetAnimCurScreen(s,p) ((s)->devPrivates[AnimCurScreenPrivateIndex].ptr = (pointer) (p))

#define Wrap(as,s,elt,func) (((as)->elt = (s)->elt), (s)->elt = func)
#define Unwrap(as,s,elt)    ((s)->elt = (as)->elt)

static Bool
 AnimCurDisplayCursor(ScreenPtr pScreen, CursorPtr pCursor);

static Bool
 AnimCurSetCursorPosition(ScreenPtr pScreen, int x, int y, Bool generateEvent);

static Bool
AnimCurCloseScreen(int index, ScreenPtr pScreen)
{
    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    Bool ret;

    Unwrap(as, pScreen, CloseScreen);

    Unwrap(as, pScreen, BlockHandler);

    Unwrap(as, pScreen, CursorLimits);
    Unwrap(as, pScreen, DisplayCursor);
    Unwrap(as, pScreen, SetCursorPosition);
    Unwrap(as, pScreen, RealizeCursor);
    Unwrap(as, pScreen, UnrealizeCursor);
    Unwrap(as, pScreen, RecolorCursor);
    SetAnimCurScreen(pScreen, 0);
    ret = (*pScreen->CloseScreen) (index, pScreen);
    free(as);
    if (index == 0)
        AnimCurScreenPrivateIndex = -1;
    return ret;
}

static void
AnimCurCursorLimits(ScreenPtr pScreen,
                    CursorPtr pCursor, BoxPtr pHotBox, BoxPtr pTopLeftBox)
{
    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    Unwrap(as, pScreen, CursorLimits);
    if (IsAnimCur(pCursor)) {
        AnimCurPtr ac = GetAnimCur(pCursor);

        (*pScreen->CursorLimits) (pScreen, ac->elts[0].pCursor, pHotBox,
                                  pTopLeftBox);
    }
    else {
        (*pScreen->CursorLimits) (pScreen, pCursor, pHotBox, pTopLeftBox);
    }
    Wrap(as, pScreen, CursorLimits, AnimCurCursorLimits);
}

/*
 * This has to be a screen block handler instead of a generic
 * block handler so that it is well ordered with respect to the DRI
 * block handler responsible for releasing the hardware to DRI clients
 */

static void
AnimCurScreenBlockHandler(int screenNum,
                          pointer blockData,
                          pointer pTimeout, pointer pReadmask)
{
    ScreenPtr pScreen = screenInfo.screens[screenNum];

    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    if (pScreen == animCurState.pScreen) {
        CARD32 now = GetTimeInMillis();

        if ((INT32) (now - animCurState.time) >= 0) {
            AnimCurPtr ac = GetAnimCur(animCurState.pCursor);

            int elt = (animCurState.elt + 1) % ac->nelt;

            DisplayCursorProcPtr DisplayCursor;

            /*
             * Not a simple Unwrap/Wrap as this
             * isn't called along the DisplayCursor
             * wrapper chain.
             */
            DisplayCursor = pScreen->DisplayCursor;
            pScreen->DisplayCursor = as->DisplayCursor;
            (void) (*pScreen->DisplayCursor) (pScreen, ac->elts[elt].pCursor);
            as->DisplayCursor = pScreen->DisplayCursor;
            pScreen->DisplayCursor = DisplayCursor;

            animCurState.elt = elt;
            animCurState.time = now + ac->elts[elt].delay;
        }
        AdjustWaitForDelay(pTimeout, animCurState.time - now);
    }
    Unwrap(as, pScreen, BlockHandler);
    (*pScreen->BlockHandler) (screenNum, blockData, pTimeout, pReadmask);
    Wrap(as, pScreen, BlockHandler, AnimCurScreenBlockHandler);
}

static Bool
AnimCurDisplayCursor(ScreenPtr pScreen, CursorPtr pCursor)
{
    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    Bool ret;

    Unwrap(as, pScreen, DisplayCursor);
    if (IsAnimCur(pCursor)) {
        if (pCursor != animCurState.pCursor) {
            AnimCurPtr ac = GetAnimCur(pCursor);

            ret = (*pScreen->DisplayCursor) (pScreen, ac->elts[0].pCursor);
            if (ret) {
                animCurState.elt = 0;
                animCurState.time = GetTimeInMillis() + ac->elts[0].delay;
                animCurState.pCursor = pCursor;
                animCurState.pScreen = pScreen;
            }
        }
        else
            ret = TRUE;
    }
    else {
        animCurState.pCursor = 0;
        animCurState.pScreen = 0;
        ret = (*pScreen->DisplayCursor) (pScreen, pCursor);
    }
    Wrap(as, pScreen, DisplayCursor, AnimCurDisplayCursor);
    return ret;
}

static Bool
AnimCurSetCursorPosition(ScreenPtr pScreen, int x, int y, Bool generateEvent)
{
    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    Bool ret;

    Unwrap(as, pScreen, SetCursorPosition);
    if (animCurState.pCursor)
        animCurState.pScreen = pScreen;
    ret = (*pScreen->SetCursorPosition) (pScreen, x, y, generateEvent);
    Wrap(as, pScreen, SetCursorPosition, AnimCurSetCursorPosition);
    return ret;
}

static Bool
AnimCurRealizeCursor(ScreenPtr pScreen, CursorPtr pCursor)
{
    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    Bool ret;

    Unwrap(as, pScreen, RealizeCursor);
    if (IsAnimCur(pCursor))
        ret = TRUE;
    else
        ret = (*pScreen->RealizeCursor) (pScreen, pCursor);
    Wrap(as, pScreen, RealizeCursor, AnimCurRealizeCursor);
    return ret;
}

static Bool
AnimCurUnrealizeCursor(ScreenPtr pScreen, CursorPtr pCursor)
{
    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    Bool ret;

    Unwrap(as, pScreen, UnrealizeCursor);
    if (IsAnimCur(pCursor)) {
        AnimCurPtr ac = GetAnimCur(pCursor);

        int i;

        if (pScreen->myNum == 0)
            for (i = 0; i < ac->nelt; i++)
                FreeCursor(ac->elts[i].pCursor, 0);
        ret = TRUE;
    }
    else
        ret = (*pScreen->UnrealizeCursor) (pScreen, pCursor);
    Wrap(as, pScreen, UnrealizeCursor, AnimCurUnrealizeCursor);
    return ret;
}

static void
AnimCurRecolorCursor(ScreenPtr pScreen, CursorPtr pCursor, Bool displayed)
{
    AnimCurScreenPtr as = GetAnimCurScreen(pScreen);

    Unwrap(as, pScreen, RecolorCursor);
    if (IsAnimCur(pCursor)) {
        AnimCurPtr ac = GetAnimCur(pCursor);

        int i;

        for (i = 0; i < ac->nelt; i++)
            (*pScreen->RecolorCursor) (pScreen, ac->elts[i].pCursor,
                                       displayed && animCurState.elt == i);
    }
    else
        (*pScreen->RecolorCursor) (pScreen, pCursor, displayed);
    Wrap(as, pScreen, RecolorCursor, AnimCurRecolorCursor);
}

Bool
AnimCurInit(ScreenPtr pScreen)
{
    AnimCurScreenPtr as;

    if (AnimCurGeneration != serverGeneration) {
        AnimCurScreenPrivateIndex = AllocateScreenPrivateIndex();
        if (AnimCurScreenPrivateIndex < 0)
            return FALSE;
        AnimCurGeneration = serverGeneration;
        animCurState.pCursor = 0;
        animCurState.pScreen = 0;
        animCurState.elt = 0;
        animCurState.time = 0;
    }
    as = malloc(sizeof(AnimCurScreenRec));
    if (!as)
        return FALSE;
    Wrap(as, pScreen, CloseScreen, AnimCurCloseScreen);

    Wrap(as, pScreen, BlockHandler, AnimCurScreenBlockHandler);

    Wrap(as, pScreen, CursorLimits, AnimCurCursorLimits);
    Wrap(as, pScreen, DisplayCursor, AnimCurDisplayCursor);
    Wrap(as, pScreen, SetCursorPosition, AnimCurSetCursorPosition);
    Wrap(as, pScreen, RealizeCursor, AnimCurRealizeCursor);
    Wrap(as, pScreen, UnrealizeCursor, AnimCurUnrealizeCursor);
    Wrap(as, pScreen, RecolorCursor, AnimCurRecolorCursor);
    SetAnimCurScreen(pScreen, as);
    return TRUE;
}

int
AnimCursorCreate(CursorPtr *cursors, CARD32 *deltas, int ncursor,
                 CursorPtr *ppCursor)
{
    CursorPtr pCursor;

    int i;

    AnimCurPtr ac;

    for (i = 0; i < screenInfo.numScreens; i++)
        if (!GetAnimCurScreenIfSet(screenInfo.screens[i]))
            return BadImplementation;

    for (i = 0; i < ncursor; i++)
        if (IsAnimCur(cursors[i]))
            return BadMatch;

    pCursor = malloc(sizeof(CursorRec) +
                                 sizeof(AnimCurRec) +
                                 ncursor * sizeof(AnimCurElt));
    if (!pCursor)
        return BadAlloc;
    pCursor->bits = &animCursorBits;
    animCursorBits.refcnt++;
    pCursor->refcnt = 1;

    pCursor->foreRed = cursors[0]->foreRed;
    pCursor->foreGreen = cursors[0]->foreGreen;
    pCursor->foreBlue = cursors[0]->foreBlue;

    pCursor->backRed = cursors[0]->backRed;
    pCursor->backGreen = cursors[0]->backGreen;
    pCursor->backBlue = cursors[0]->backBlue;

    /*
     * Fill in the AnimCurRec
     */
    ac = GetAnimCur(pCursor);
    ac->nelt = ncursor;
    ac->elts = (AnimCurElt *) (ac + 1);

    for (i = 0; i < ncursor; i++) {
        cursors[i]->refcnt++;
        ac->elts[i].pCursor = cursors[i];
        ac->elts[i].delay = deltas[i];
    }

    *ppCursor = pCursor;
    return Success;
}