/*

    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"

/* This is the CD-audio control API for Simple DirectMedia Layer */

#include "SDL_cdrom.h"

#include "SDL_syscdrom.h"

#if !defined(__MACOS__)

#define CLIP_FRAMES	10	/* Some CD-ROMs won't go all the way */

#endif

static int SDL_cdinitted = 0;

static SDL_CD *default_cdrom;

/* The system level CD-ROM control functions */

struct CDcaps SDL_CDcaps = {

	NULL,					/* Name */

	NULL,					/* Open */

	NULL,					/* GetTOC */

	NULL,					/* Status */

	NULL,					/* Play */

	NULL,					/* Pause */

	NULL,					/* Resume */

	NULL,					/* Stop */

	NULL,					/* Eject */

	NULL,					/* Close */

};

int SDL_numcds;

int SDL_CDROMInit(void)

{

	int retval;

	SDL_numcds = 0;

	retval = SDL_SYS_CDInit();

	if ( retval == 0 ) {

		SDL_cdinitted = 1;

	}

	default_cdrom = NULL;

	return(retval);

}

/* Check to see if the CD-ROM subsystem has been initialized */

static int CheckInit(int check_cdrom, SDL_CD **cdrom)

{

	int okay;

	okay = SDL_cdinitted;

	if ( check_cdrom && (*cdrom == NULL) ) {

		*cdrom = default_cdrom;

		if ( *cdrom == NULL ) {

			SDL_SetError("CD-ROM not opened");

			okay = 0;

		}

	}

	if ( ! SDL_cdinitted ) {

		SDL_SetError("CD-ROM subsystem not initialized");

	}

	return(okay);

}

int SDL_CDNumDrives(void)

{

	if ( ! CheckInit(0, NULL) ) {

		return(-1);

	}

	return(SDL_numcds);

}

const char *SDL_CDName(int drive)

{

	if ( ! CheckInit(0, NULL) ) {

		return(NULL);

	}

	if ( drive >= SDL_numcds ) {

		SDL_SetError("Invalid CD-ROM drive index");

		return(NULL);

	}

	if ( SDL_CDcaps.Name ) {

		return(SDL_CDcaps.Name(drive));

	} else {

		return("");

	}

}

SDL_CD *SDL_CDOpen(int drive)

{

	struct SDL_CD *cdrom;

	if ( ! CheckInit(0, NULL) ) {

		return(NULL);

	}

	if ( drive >= SDL_numcds ) {

		SDL_SetError("Invalid CD-ROM drive index");

		return(NULL);

	}

	cdrom = (SDL_CD *)SDL_malloc(sizeof(*cdrom));

	if ( cdrom == NULL ) {

		SDL_OutOfMemory();

		return(NULL);

	}

	SDL_memset(cdrom, 0, sizeof(*cdrom));

	cdrom->id = SDL_CDcaps.Open(drive);

	if ( cdrom->id < 0 ) {

		SDL_free(cdrom);

		return(NULL);

	}

	default_cdrom = cdrom;

	return(cdrom);

}

CDstatus SDL_CDStatus(SDL_CD *cdrom)

{

	CDstatus status;

	int i;

	Uint32 position;

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return(CD_ERROR);

	}

	/* Get the current status of the drive */

	cdrom->numtracks = 0;

	cdrom->cur_track = 0;

	cdrom->cur_frame = 0;

	status = SDL_CDcaps.Status(cdrom, &i);

	position = (Uint32)i;

	cdrom->status = status;

	/* Get the table of contents, if there's a CD available */

	if ( CD_INDRIVE(status) ) {

		if ( SDL_CDcaps.GetTOC(cdrom) < 0 ) {

			status = CD_ERROR;

		}

		/* If the drive is playing, get current play position */

		if ( (status == CD_PLAYING) || (status == CD_PAUSED) ) {

			for ( i=1; cdrom->track[i].offset <= position; ++i ) {

				/* Keep looking */;

			}

#ifdef DEBUG_CDROM

  fprintf(stderr, "Current position: %d, track = %d (offset is %d)\n",

				position, i-1, cdrom->track[i-1].offset);

#endif

			cdrom->cur_track = i-1;

			position -= cdrom->track[cdrom->cur_track].offset;

			cdrom->cur_frame = position;

		}

	}

	return(status);

}

int SDL_CDPlayTracks(SDL_CD *cdrom,

			int strack, int sframe, int ntracks, int nframes)

{

	int etrack, eframe;

	int start, length;

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return(CD_ERROR);

	}

	/* Determine the starting and ending tracks */

	if ( (strack < 0) || (strack >= cdrom->numtracks) ) {

		SDL_SetError("Invalid starting track");

		return(CD_ERROR);

	}

	if ( ! ntracks && ! nframes ) {

		etrack = cdrom->numtracks;

		eframe = 0;

	} else {

		etrack = strack+ntracks;

		if ( etrack == strack ) {

			eframe = sframe + nframes;

		} else {

			eframe = nframes;

		}

	}

	if ( etrack > cdrom->numtracks ) {

		SDL_SetError("Invalid play length");

		return(CD_ERROR);

	}

	/* Skip data tracks and verify frame offsets */

	while ( (strack <= etrack) &&

			(cdrom->track[strack].type == SDL_DATA_TRACK) ) {

		++strack;

	}

	if ( sframe >= (int)cdrom->track[strack].length ) {

		SDL_SetError("Invalid starting frame for track %d", strack);

		return(CD_ERROR);

	}

	while ( (etrack > strack) &&

			(cdrom->track[etrack-1].type == SDL_DATA_TRACK) ) {

		--etrack;

	}

	if ( eframe > (int)cdrom->track[etrack].length ) {

		SDL_SetError("Invalid ending frame for track %d", etrack);

		return(CD_ERROR);

	}

	/* Determine start frame and play length */

	start = (cdrom->track[strack].offset+sframe);

	length = (cdrom->track[etrack].offset+eframe)-start;

#ifdef CLIP_FRAMES

	/* I've never seen this necessary, but xmcd does it.. */

	length -= CLIP_FRAMES;	/* CLIP_FRAMES == 10 */

#endif

	if ( length < 0 ) {

		return(0);

	}

	/* Play! */

#ifdef DEBUG_CDROM

  fprintf(stderr, "Playing %d frames at offset %d\n", length, start);

#endif

	return(SDL_CDcaps.Play(cdrom, start, length));

}

int SDL_CDPlay(SDL_CD *cdrom, int sframe, int length)

{

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return(CD_ERROR);

	}

	return(SDL_CDcaps.Play(cdrom, sframe, length));

}

int SDL_CDPause(SDL_CD *cdrom)

{

	CDstatus status;

	int retval;

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return(CD_ERROR);

	}

	status = SDL_CDcaps.Status(cdrom, NULL);

	switch (status) {

		case CD_PLAYING:

			retval = SDL_CDcaps.Pause(cdrom);

			break;

		default:

			retval = 0;

			break;

	}

	return(retval);

}

int SDL_CDResume(SDL_CD *cdrom)

{

	CDstatus status;

	int retval;

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return(CD_ERROR);

	}

	status = SDL_CDcaps.Status(cdrom, NULL);

	switch (status) {

		case CD_PAUSED:

			retval = SDL_CDcaps.Resume(cdrom);

		default:

			retval = 0;

			break;

	}

	return(retval);

}

int SDL_CDStop(SDL_CD *cdrom)

{

	CDstatus status;

	int retval;

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return(CD_ERROR);

	}

	status = SDL_CDcaps.Status(cdrom, NULL);

	switch (status) {

		case CD_PLAYING:

		case CD_PAUSED:

			retval = SDL_CDcaps.Stop(cdrom);

		default:

			retval = 0;

			break;

	}

	return(retval);

}

int SDL_CDEject(SDL_CD *cdrom)

{

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return(CD_ERROR);

	}

	return(SDL_CDcaps.Eject(cdrom));

}

void SDL_CDClose(SDL_CD *cdrom)

{

	/* Check if the CD-ROM subsystem has been initialized */

	if ( ! CheckInit(1, &cdrom) ) {

		return;

	}

	SDL_CDcaps.Close(cdrom);

	SDL_free(cdrom);

	default_cdrom = NULL;

}

void SDL_CDROMQuit(void)

{

	SDL_SYS_CDQuit();

	SDL_cdinitted = 0;

}