/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Lesser General Public

    License as published by the Free Software Foundation; either

    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public

    License along with this library; if not, write to the Free Software

    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga

    slouken@libsdl.org

*/

#include "SDL_config.h"

#ifdef SDL_CDROM_MACOSX

#include "SDL_syscdrom_c.h"

#pragma mark -- Globals --

static FSRef**         tracks;

static FSVolumeRefNum* volumes;

static CDstatus        status;

static int             nextTrackFrame;

static int             nextTrackFramesRemaining;

static int             fakeCD;

static int             currentTrack;

static int             didReadTOC;

static int             cacheTOCNumTracks;

static int             currentDrive; /* Only allow 1 drive in use at a time */

#pragma mark -- Prototypes --

static const char *SDL_SYS_CDName   (int drive);

static int         SDL_SYS_CDOpen   (int drive);

static int         SDL_SYS_CDGetTOC (SDL_CD *cdrom);

static CDstatus    SDL_SYS_CDStatus (SDL_CD *cdrom, int *position);

static int         SDL_SYS_CDPlay   (SDL_CD *cdrom, int start, int length);

static int         SDL_SYS_CDPause  (SDL_CD *cdrom);

static int         SDL_SYS_CDResume (SDL_CD *cdrom);

static int         SDL_SYS_CDStop   (SDL_CD *cdrom);

static int         SDL_SYS_CDEject  (SDL_CD *cdrom);

static void        SDL_SYS_CDClose  (SDL_CD *cdrom);

#pragma mark -- Helper Functions --

/* Read a list of tracks from the volume */

static int LoadTracks (SDL_CD *cdrom)

{

    /* Check if tracks are already loaded */

    if  ( tracks[cdrom->id] != NULL )

        return 0;

    /* Allocate memory for tracks */

    tracks[cdrom->id] = (FSRef*) SDL_calloc (1, sizeof(**tracks) * cdrom->numtracks);

    if (tracks[cdrom->id] == NULL) {

        SDL_OutOfMemory ();

        return -1;

    }

    /* Load tracks */

    if (ListTrackFiles (volumes[cdrom->id], tracks[cdrom->id], cdrom->numtracks) < 0)

        return -1;

    return 0;

}

/* Find a file for a given start frame and length */

static FSRef* GetFileForOffset (SDL_CD *cdrom, int start, int length,  int *outStartFrame, int *outStopFrame)

{

    int i;

    for (i = 0; i < cdrom->numtracks; i++) {

        if (cdrom->track[i].offset <= start &&

            start < (cdrom->track[i].offset + cdrom->track[i].length))

            break;

    }

    if (i == cdrom->numtracks)

        return NULL;

    currentTrack = i;

    *outStartFrame = start - cdrom->track[i].offset;

    if ((*outStartFrame + length) < cdrom->track[i].length) {

        *outStopFrame = *outStartFrame + length;

        length = 0;

        nextTrackFrame = -1;

        nextTrackFramesRemaining = -1;

    }

    else {

        *outStopFrame = -1;

        length -= cdrom->track[i].length - *outStartFrame;

        nextTrackFrame = cdrom->track[i+1].offset;

        nextTrackFramesRemaining = length;

    }

    return &tracks[cdrom->id][i];

}

/* Setup another file for playback, or stop playback (called from another thread) */

static void CompletionProc (SDL_CD *cdrom)

{

    Lock ();

    if (nextTrackFrame > 0 && nextTrackFramesRemaining > 0) {

        /* Load the next file to play */

        int startFrame, stopFrame;

        FSRef *file;

        PauseFile ();

        ReleaseFile ();

        file = GetFileForOffset (cdrom, nextTrackFrame, 

            nextTrackFramesRemaining, &startFrame, &stopFrame);

        if (file == NULL) {

            status = CD_STOPPED;

            Unlock ();

            return;

        }

        LoadFile (file, startFrame, stopFrame);

        SetCompletionProc (CompletionProc, cdrom);

        PlayFile ();

    }

    else {

        /* Release the current file */

        PauseFile ();

        ReleaseFile ();

        status = CD_STOPPED;

    }

    Unlock ();

}

#pragma mark -- Driver Functions --

/* Initialize */

int SDL_SYS_CDInit (void) 

{

    /* Initialize globals */

    volumes = NULL;

    tracks  = NULL;

    status  = CD_STOPPED;

    nextTrackFrame = -1;

    nextTrackFramesRemaining = -1;

    fakeCD  = SDL_FALSE;

    currentTrack = -1;

    didReadTOC = SDL_FALSE;

    cacheTOCNumTracks = -1;

    currentDrive = -1;

    /* Fill in function pointers */

    SDL_CDcaps.Name   = SDL_SYS_CDName;

    SDL_CDcaps.Open   = SDL_SYS_CDOpen;

    SDL_CDcaps.GetTOC = SDL_SYS_CDGetTOC;

    SDL_CDcaps.Status = SDL_SYS_CDStatus;

    SDL_CDcaps.Play   = SDL_SYS_CDPlay;

    SDL_CDcaps.Pause  = SDL_SYS_CDPause;

    SDL_CDcaps.Resume = SDL_SYS_CDResume;

    SDL_CDcaps.Stop   = SDL_SYS_CDStop;

    SDL_CDcaps.Eject  = SDL_SYS_CDEject;

    SDL_CDcaps.Close  = SDL_SYS_CDClose;

    /* 

        Read the list of "drives"

        This is currently a hack that infers drives from

        mounted audio CD volumes, rather than

        actual CD-ROM devices - which means it may not

        act as expected sometimes.

    */

    /* Find out how many cd volumes are mounted */

    SDL_numcds = DetectAudioCDVolumes (NULL, 0);

    /*

        If there are no volumes, fake a cd device

        so tray empty can be reported.

    */

    if (SDL_numcds == 0) {

        fakeCD = SDL_TRUE;

        SDL_numcds = 1;

        status = CD_TRAYEMPTY;

        return 0;

    }

    /* Allocate space for volumes */

    volumes = (FSVolumeRefNum*) SDL_calloc (1, sizeof(*volumes) * SDL_numcds);

    if (volumes == NULL) {

        SDL_OutOfMemory ();

        return -1;

    }

    /* Allocate space for tracks */

    tracks = (FSRef**) SDL_calloc (1, sizeof(*tracks) * (SDL_numcds + 1));

    if (tracks == NULL) {

        SDL_OutOfMemory ();

        return -1;

    }

    /* Mark the end of the tracks array */

    tracks[ SDL_numcds ] = (FSRef*)-1;

    /* 

        Redetect, now save all volumes for later

        Update SDL_numcds just in case it changed

    */

    {

        int numVolumes = SDL_numcds;

        SDL_numcds = DetectAudioCDVolumes (volumes, numVolumes);

        /* If more cds suddenly show up, ignore them */

        if (SDL_numcds > numVolumes) {

            SDL_SetError ("Some CD's were added but they will be ignored");

            SDL_numcds = numVolumes;

        }

    }

    return 0;

}

/* Shutdown and cleanup */

void SDL_SYS_CDQuit(void)

{

    ReleaseFile();

    if (volumes != NULL)

        free (volumes);

    if (tracks != NULL) {

        FSRef **ptr;

        for (ptr = tracks; *ptr != (FSRef*)-1; ptr++)

            if (*ptr != NULL)

                free (*ptr);

        free (tracks);

    }

}

/* Get the Unix disk name of the volume */

static const char *SDL_SYS_CDName (int drive)

{

    OSStatus     err = noErr;

    HParamBlockRec  pb;

    GetVolParmsInfoBuffer   volParmsInfo;

    if (fakeCD)

        return "Fake CD-ROM Device";

    pb.ioParam.ioNamePtr = NULL;

    pb.ioParam.ioVRefNum = volumes[drive];

    pb.ioParam.ioBuffer = (Ptr)&volParmsInfo;

    pb.ioParam.ioReqCount = (SInt32)sizeof(volParmsInfo);

    err = PBHGetVolParmsSync(&pb);

    if (err != noErr) {

        SDL_SetError ("PBHGetVolParmsSync returned %d", err);

        return NULL;

    }

    return volParmsInfo.vMDeviceID;

}

/* Open the "device" */

static int SDL_SYS_CDOpen (int drive)

{

    /* Only allow 1 device to be open */

    if (currentDrive >= 0) {

        SDL_SetError ("Only one cdrom is supported");

        return -1;

    }

    else

        currentDrive = drive;

    return drive;

}

/* Get the table of contents */

static int SDL_SYS_CDGetTOC (SDL_CD *cdrom)

{

    if (fakeCD) {

        SDL_SetError (kErrorFakeDevice);

        return -1;

    }

    if (didReadTOC) {

        cdrom->numtracks = cacheTOCNumTracks;

        return 0;

    }

    ReadTOCData (volumes[cdrom->id], cdrom);

    didReadTOC = SDL_TRUE;

    cacheTOCNumTracks = cdrom->numtracks;

    return 0;

}

/* Get CD-ROM status */

static CDstatus SDL_SYS_CDStatus (SDL_CD *cdrom, int *position)

{

    if (position) {

        int trackFrame;

        Lock ();

        trackFrame = GetCurrentFrame ();

        Unlock ();

        *position = cdrom->track[currentTrack].offset + trackFrame;

    }

    return status;

}

/* Start playback */

static int SDL_SYS_CDPlay(SDL_CD *cdrom, int start, int length)

{

    int startFrame, stopFrame;

    FSRef *ref;

    if (fakeCD) {

        SDL_SetError (kErrorFakeDevice);

        return -1;

    }

    Lock();

    if (LoadTracks (cdrom) < 0)

        return -2;

    if (PauseFile () < 0)

        return -3;

    if (ReleaseFile () < 0)

        return -4;

    ref = GetFileForOffset (cdrom, start, length, &startFrame, &stopFrame);

    if (ref == NULL) {

        SDL_SetError ("SDL_SYS_CDPlay: No file for start=%d, length=%d", start, length);

        return -5;

    }

    if (LoadFile (ref, startFrame, stopFrame) < 0)

        return -6;

    SetCompletionProc (CompletionProc, cdrom);

    if (PlayFile () < 0)

        return -7;

    status = CD_PLAYING;

    Unlock();

    return 0;

}

/* Pause playback */

static int SDL_SYS_CDPause(SDL_CD *cdrom)

{

    if (fakeCD) {

        SDL_SetError (kErrorFakeDevice);

        return -1;

    }

    Lock ();

    if (PauseFile () < 0) {

        Unlock ();

        return -2;

    }

    status = CD_PAUSED;

    Unlock ();

    return 0;

}

/* Resume playback */

static int SDL_SYS_CDResume(SDL_CD *cdrom)

{

    if (fakeCD) {

        SDL_SetError (kErrorFakeDevice);

        return -1;

    }

    Lock ();

    if (PlayFile () < 0) {

        Unlock ();

        return -2;

    }

    status = CD_PLAYING;

    Unlock ();

    return 0;

}

/* Stop playback */

static int SDL_SYS_CDStop(SDL_CD *cdrom)

{

    if (fakeCD) {

        SDL_SetError (kErrorFakeDevice);

        return -1;

    }

    Lock ();

    if (PauseFile () < 0) {

        Unlock ();

        return -2;

    }

    if (ReleaseFile () < 0) {

        Unlock ();

        return -3;

    }

    status = CD_STOPPED;

    Unlock ();

    return 0;

}

/* Eject the CD-ROM (Unmount the volume) */

static int SDL_SYS_CDEject(SDL_CD *cdrom)

{

    OSStatus err;

    if (fakeCD) {

        SDL_SetError (kErrorFakeDevice);

        return -1;

    }

    Lock ();

    if (PauseFile () < 0) {

        Unlock ();

        return -2;

    }

    if (ReleaseFile () < 0) {

        Unlock ();

        return -3;

    }

    status = CD_STOPPED;

	/* Eject the volume */

	if (err != noErr) {

        Unlock ();

		SDL_SetError ("PBUnmountVol returned %d", err);

		return -4;

	}

    status = CD_TRAYEMPTY;

    /* Invalidate volume and track info */

    volumes[cdrom->id] = 0;

    free (tracks[cdrom->id]);

    tracks[cdrom->id] = NULL;

    Unlock ();

    return 0;

}

/* Close the CD-ROM */

static void SDL_SYS_CDClose(SDL_CD *cdrom)

{

    currentDrive = -1;

    return;

}

#endif /* SDL_CDROM_MACOSX */