/**

 * $Id$

 *

 * Nero (NRG) CD file format. File information stolen shamelessly from

 * libcdio.

 *

 * Copyright (c) 2005 Nathan Keynes.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 */

#include <assert.h>

#include <stdio.h>

#include <errno.h>

#include <glib/gtypes.h>

#include "gdrom/gddriver.h"

#include "dream.h"

static gboolean nrg_image_is_valid( FILE *f );

static gdrom_disc_t nrg_image_open( const gchar *filename, FILE *f );

struct gdrom_image_class nrg_image_class = { "Nero", "nrg", 

        nrg_image_is_valid, nrg_image_open };

#define NERO_V55_ID  0x4e455235 

#define NERO_V50_ID  0x4e45524f 

/* Courtesy of libcdio */

/* 5.0 or earlier */

#define NERO_ID  0x4e45524f  /* Nero pre 5.5.x */

#define CUES_ID  0x43554553  /* Nero pre version 5.5.x-6.x */

#define DAOI_ID  0x44414f49

#define ETNF_ID  0x45544e46

#define SINF_ID  0x53494e46  /* Session information */

#define END_ID  0x454e4421

/* 5.5+ only */

#define NER5_ID  0x4e455235  /* Nero version 5.5.x */

#define CDTX_ID  0x43445458  /* CD TEXT */

#define CUEX_ID  0x43554558  /* Nero version 5.5.x-6.x */

#define DAOX_ID  0x44414f58  /* Nero version 5.5.x-6.x */

#define ETN2_ID  0x45544e32

#define MTYP_ID  0x4d545950  /* Disc Media type? */

union nrg_footer {

    struct nrg_footer_v50 {

        uint32_t dummy;

        uint32_t id;

        uint32_t offset;

    } v50;

    struct nrg_footer_v55 {

        uint32_t id;

        uint64_t offset;

    } v55;

};

struct nrg_chunk {

    uint32_t id;

    uint32_t length;

};

struct nrg_etnf {

    uint32_t offset;

    uint32_t length;

    uint32_t mode;

    uint32_t lba;

    uint32_t padding;

};

struct nrg_etn2 {

    uint64_t offset;

    uint64_t length;

    uint32_t mode;

    uint32_t lba;

    uint64_t padding;

};

struct nrg_cues {

    uint8_t type;

    uint8_t track;

    uint8_t control;

    uint8_t pad;

    uint32_t addr;

};

struct nrg_daoi {

    uint32_t length;

    char mcn[14];

    uint8_t disc_mode;

    uint8_t unknown[2]; /* always 01 01? */

    uint8_t track_count;

    struct nrg_daoi_track {

        char unknown[10];

        uint32_t sector_size __attribute__((packed)); /* Always 0? */

        uint8_t mode;

        uint8_t unknown2[3]; /* Always 00 00 01? */

        uint32_t pregap __attribute__((packed));

        uint32_t offset __attribute__((packed));

        uint32_t end __attribute__((packed));

    } track[0];

} __attribute__((packed));

struct nrg_daox {

    uint32_t length;

    char mcn[14];

    uint8_t disc_mode;

    uint8_t unknown[2]; /* always 01 01? */

    uint8_t track_count;

    struct nrg_daox_track {

        char unknown[10];

        uint32_t sector_size __attribute__((packed)); /* Always 0? */

        uint8_t mode;

        uint8_t unknown2[3]; /* Always 00 00 01? */

        uint64_t pregap __attribute__((packed));

        uint64_t offset __attribute__((packed));

        uint64_t end __attribute__((packed));

    } track[0];

} __attribute__((packed));

/**

 * Convert an 8-bit BCD number to normal integer form. 

 * Eg, 0x79 => 79

 */

uint8_t static bcd_to_uint8( uint8_t bcd )

{

    return (bcd & 0x0F) + (((bcd & 0xF0)>>4)*10);

}

/**

 * Convert a 32 bit MSF address (BCD coded) to the

 * equivalent LBA form. 

 * Eg, 0x

 */

uint32_t static msf_to_lba( uint32_t msf )

{

    msf = GUINT32_FROM_BE(msf);

    int f = bcd_to_uint8(msf);

    int s = bcd_to_uint8(msf>>8);

    int m = bcd_to_uint8(msf>>16);

    return (m * 60 + s) * 75 + f;

}

uint32_t static nrg_track_mode( uint8_t mode )

{

    switch( mode ) {

    case 0: return GDROM_MODE1;

    case 2: return GDROM_MODE2_FORM1;

    case 3: return GDROM_SEMIRAW_MODE2;

    case 7: return GDROM_CDDA;

    default: 

        ERROR( "Unrecognized track mode %d in Nero image", mode );

        return -1;

    }

}

static gboolean nrg_image_is_valid( FILE *f )

{

    union nrg_footer footer;

    fseek( f, -12, SEEK_END );

    fread( &footer, sizeof(footer), 1, f );

    if( GUINT32_FROM_BE(footer.v50.id) == NERO_V50_ID ||

            GUINT32_FROM_BE(footer.v55.id) == NERO_V55_ID ) {

        return TRUE;

    } else {

        return FALSE;

    }

}

static gdrom_disc_t nrg_image_open( const gchar *filename, FILE *f )

{

    union nrg_footer footer;

    struct nrg_chunk chunk;

    struct nrg_daoi *dao;

    struct nrg_daox *daox;

    struct nrg_etnf *etnf;

    struct nrg_etn2 *etn2;

    gdrom_disc_t disc;

    gdrom_image_t image;

    gboolean end = FALSE;

    uint32_t chunk_id;

    int session_id = 0;

    int session_track_id = 0;

    int track_id = 0;

    int cue_track_id = 0, cue_track_count = 0;

    int i, count;

    fseek( f, -12, SEEK_END );

    fread( &footer, sizeof(footer), 1, f );

    if( GUINT32_FROM_BE(footer.v50.id) == NERO_V50_ID ) {

        INFO( "Loading Nero 5.0 image" );

        fseek( f, GUINT32_FROM_BE(footer.v50.offset), SEEK_SET );

    } else if( GUINT32_FROM_BE(footer.v55.id) == NERO_V55_ID ) {

        INFO( "Loading Nero 5.5+ image" );

        fseek( f, (uint32_t)GUINT64_FROM_BE(footer.v55.offset), SEEK_SET );

    } else {

        /* Not a (recognized) Nero image */

        return NULL;

    }

    disc = gdrom_image_new(filename, f);

    if( disc == NULL ) {

        ERROR("Unable to allocate memory!");

        return NULL;

    }

    image = (gdrom_image_t)disc;

    do {

        fread( &chunk, sizeof(chunk), 1, f );

        chunk.length = GUINT32_FROM_BE(chunk.length);

        char data[chunk.length];

        fread( data, chunk.length, 1, f );

        chunk_id = GUINT32_FROM_BE(chunk.id);

        switch( chunk_id ) {

        case CUES_ID:

        case CUEX_ID:

            cue_track_id = track_id;

            cue_track_count = ((chunk.length / sizeof(struct nrg_cues)) >> 1) - 1;

            track_id += cue_track_count;

            for( i=0; i<chunk.length; i+= sizeof(struct nrg_cues) ) {

                struct nrg_cues *cue = (struct nrg_cues *)(data+i);

                int track = 0;

                uint32_t lba;

                if( chunk_id == CUEX_ID ) {

                    lba = GUINT32_FROM_BE( cue->addr ) + GDROM_PREGAP;

                } else {

                    lba = msf_to_lba( cue->addr );

                }

                if( cue->track == 0 )

                    continue; /* Track 0. Leadin? always 0? */

                if( cue->track == 0xAA ) { /* end of disc */

                    image->track[track_id-1].sector_count =

                        lba - image->track[track_id-1].lba;

                } else {

                    track = bcd_to_uint8(cue->track) - 1;

                    if( (cue->control & 0x01) == 0 ) { 

                        /* Pre-gap address. */

                        if( track != 0 ) {

                            image->track[track-1].sector_count = 

                                lba - image->track[track-1].lba;

                        }

                    } else { /* Track-start address */

                        image->track[track].lba = lba;

                        image->track[track].flags = cue->type;

                    }

                }

            }

            break;

        case DAOI_ID:

            dao = (struct nrg_daoi *)data;

            memcpy( image->mcn, dao->mcn, 13 );

            image->mcn[13] = '\0';

            assert( (dao->track_count - cue_track_id) * 30 + 22 == chunk.length );

            assert( dao->track_count == track_id );

            for( i=0; i<(dao->track_count-cue_track_id); i++ ) {

                image->track[cue_track_id].sector_size = GUINT32_FROM_BE(dao->track[i].sector_size);

                image->track[cue_track_id].offset = GUINT32_FROM_BE(dao->track[i].offset);

                image->track[cue_track_id].mode = nrg_track_mode( dao->track[i].mode );

                image->track[cue_track_id].sector_count =

                    (GUINT32_FROM_BE(dao->track[i].end) - GUINT32_FROM_BE(dao->track[i].offset))/

                    GUINT32_FROM_BE(dao->track[i].sector_size);

                cue_track_id++;

            }

            break;

        case DAOX_ID:

            daox = (struct nrg_daox *)data;

            memcpy( image->mcn, daox->mcn, 13 );

            image->mcn[13] = '\0';

            assert( (daox->track_count - cue_track_id) * 42 + 22 == chunk.length );

            assert( daox->track_count == track_id );

            for( i=0; i<(daox->track_count-cue_track_id); i++ ) {

                image->track[cue_track_id].sector_size = GUINT32_FROM_BE(daox->track[i].sector_size);

                image->track[cue_track_id].offset = GUINT64_FROM_BE(daox->track[i].offset);

                image->track[cue_track_id].mode = nrg_track_mode( daox->track[i].mode );

                image->track[cue_track_id].sector_count =

                    (GUINT64_FROM_BE(daox->track[i].end) - GUINT64_FROM_BE(daox->track[i].offset))/

                    GUINT32_FROM_BE(daox->track[i].sector_size);

                cue_track_id++;

            }

            break;

        case SINF_ID: 

            /* Data is a single 32-bit number representing number of tracks in session */

            i = GUINT32_FROM_BE( *(uint32_t *)data );

            while( i-- > 0 )

                image->track[session_track_id++].session = session_id;

            session_id++;

            break;

        case ETNF_ID:

            etnf = (struct nrg_etnf *)data;

            count = chunk.length / sizeof(struct nrg_etnf);

            for( i=0; i < count; i++, etnf++ ) {

                image->track[track_id].offset = GUINT32_FROM_BE(etnf->offset);

                image->track[track_id].lba = GUINT32_FROM_BE(etnf->lba) + (i+1)*GDROM_PREGAP;

                image->track[track_id].mode = nrg_track_mode( GUINT32_FROM_BE(etnf->mode) );

                if( image->track[track_id].mode == -1 ) {

                    gdrom_image_destroy_no_close(disc);

                    return NULL;

                }

                if( image->track[track_id].mode == GDROM_CDDA )

                    image->track[track_id].flags = 0x01;

                else

                    image->track[track_id].flags = 0x01 | TRACK_DATA;

                image->track[track_id].sector_size = GDROM_SECTOR_SIZE(image->track[track_id].mode);

                image->track[track_id].sector_count = GUINT32_FROM_BE(etnf->length) / 

                image->track[track_id].sector_size;

                track_id++;

            }

            break;

        case ETN2_ID:

            etn2 = (struct nrg_etn2 *)data;

            count = chunk.length / sizeof(struct nrg_etn2);

            for( i=0; i < count; i++, etn2++ ) {

                image->track[track_id].offset = (uint32_t)GUINT64_FROM_BE(etn2->offset);

                image->track[track_id].lba = GUINT32_FROM_BE(etn2->lba) + (i+1)*GDROM_PREGAP;

                image->track[track_id].mode = nrg_track_mode( GUINT32_FROM_BE(etn2->mode) );

                if( image->track[track_id].mode == -1 ) {

                    gdrom_image_destroy_no_close(disc);

                    return NULL;

                }

                if( image->track[track_id].mode == GDROM_CDDA )

                    image->track[track_id].flags = 0x01;

                else

                    image->track[track_id].flags = 0x01 | TRACK_DATA;

                image->track[track_id].sector_size = GDROM_SECTOR_SIZE(image->track[track_id].mode);

                image->track[track_id].sector_count = (uint32_t)(GUINT64_FROM_BE(etn2->length) / 

                        image->track[track_id].sector_size);

                track_id++;

            }

            break;

        case END_ID:

            end = TRUE;

            break;

        }

    } while( !end );

    image->track_count = track_id;

    return disc;

}