/**

 * $Id: gdrom.h,v 1.10 2007-01-31 10:58:42 nkeynes Exp $

 *

 * This file defines the structures and functions used by the GD-Rom

 * disc driver. (ie, the modules that supply a CD image to be used by the

 * system).

 *

 * 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.

 */

#ifndef dream_gdrom_H

#define dream_gdrom_H 1

#include "dream.h"

#define MAX_SECTOR_SIZE 2352

typedef uint16_t gdrom_error_t;

struct gdrom_toc {

    uint32_t track[99];

    uint32_t first, last, leadout;

};

#define GDROM_PREGAP 150  /* Sectors */

extern uint32_t gdrom_sector_size[];

#define GDROM_SECTOR_SIZE(x) gdrom_sector_size[x]

typedef enum {

    GDROM_MODE1,

    GDROM_MODE2,

    GDROM_MODE2_XA1,

    GDROM_MODE2_XA2,

    GDROM_CDDA,

    GDROM_GD,

    GDROM_RAW

} gdrom_track_mode_t;

/* The disc register indicates the current contents of the drive. When open

 * contains 0x06.

 */

#define IDE_DISC_AUDIO 0x00

#define IDE_DISC_NONE  0x06

#define IDE_DISC_CDROM 0x20

#define IDE_DISC_GDROM 0x80

#define IDE_DISC_READY 0x01 /* ored with above */

#define IDE_DISC_IDLE  0x02 /* ie spun-down */

#define TRACK_PRE_EMPHASIS   0x10

#define TRACK_COPY_PERMITTED 0x20

#define TRACK_DATA           0x40

#define TRACK_FOUR_CHANNEL   0x80

typedef struct gdrom_track {

    gdrom_track_mode_t mode;

    uint8_t flags;        /* Track flags */

    int      session;     /* session # containing this track */

    uint32_t lba;         /* start sector address */

    uint32_t sector_size; /* For convenience, determined by mode */

    uint32_t sector_count;

    uint32_t offset; /* File offset of start of track - image files only */

} *gdrom_track_t;

typedef struct gdrom_disc {

    /**

     * Read a single sector from the disc at the specified logical address.

     * @param disc pointer to the disc structure

     * @param lba logical address to read from

     * @param mode mode field from the read command

     * @param buf buffer to receive data (at least MAX_SECTOR_SIZE bytes)

     * @param length unsigned int to receive the number of bytes actually read.

     * @return PKT_ERR_OK on success, or another PKT_ERR_* code on failure.

     */

    gdrom_error_t (*read_sector)( struct gdrom_disc *disc,

				  uint32_t lba, int mode, 

				  char *buf, uint32_t *length );

    /**

     * Read the TOC from the disc and write it into the specified buffer.

     * The method is responsible for returning the data in gd-rom

     * format.

     * @param disc pointer to the disc structure

     * @param buf buffer to receive data (0x198 bytes long)

     */

    gdrom_error_t (*read_toc)(struct gdrom_disc *disc, char *buf);

    /**

     * Read the information for the specified sector and return it in the

     * supplied buffer. 

     * @param disc pointer to the disc structure

     * @param session of interest. If 0, return end of disc information.

     * @param buf buffer to receive data (6 bytes)

     */

    gdrom_error_t (*read_session)(struct gdrom_disc *disc, int session, char *buf);

    /**

     * Read the position information (subchannel) for the specified sector

     * and return it in the supplied buffer. This method does not need to

     * write the first 4 bytes of the buffer.

     * @param disc pointer to the disc structure

     * @param lba sector to get position information for

     * @param buf buffer to receive data (14 bytes)

     */

    gdrom_error_t (*read_position)(struct gdrom_disc *disc, uint32_t lba, char *buf);

    /**

     * Return the current disc status, expressed as a combination of the 

     * IDE_DISC_* flags above.

     * @param disc pointer to the disc structure

     * @return an integer status value.

     */

    int (*drive_status)(struct gdrom_disc *disc);

    /**

     * Begin playing audio from the given lba address on the disc.

     */

    gdrom_error_t (*play_audio)(struct gdrom_disc *disc, uint32_t lba);

    /**

     * Executed once per time slice to perform house-keeping operations 

     * (checking disc status, media changed, etc).

     */

    uint32_t (*run_time_slice)( struct gdrom_disc *disc, uint32_t nanosecs );

    /**

     * Close the disc and release any storage or resources allocated including

     * the disc structure itself.

     */

    void (*close)( struct gdrom_disc *disc );

} *gdrom_disc_t;

typedef struct gdrom_image {

    struct gdrom_disc disc;

    int disc_type;

    int track_count;

    struct gdrom_track track[99];

    gchar mcn[14]; /* Media catalogue number */

    const gchar *filename; /* Image filename */

    FILE *file; /* Open file stream */

} *gdrom_image_t;

/**

 *

 */

typedef struct gdrom_image_class {

    const gchar *name;

    const gchar *extension;

    gboolean (*is_valid_file)(FILE *f);

    gdrom_disc_t (*open_image_file)(const gchar *filename, FILE *f);

} *gdrom_image_class_t;

extern struct gdrom_image_class nrg_image_class;

extern struct gdrom_image_class cdi_image_class;

extern struct gdrom_image_class linux_device_class;

/**

 * Construct a new image file using the default methods.

 */

gdrom_disc_t gdrom_image_new( FILE *file );

/**

 * Open an image file

 */

gdrom_disc_t gdrom_image_open( const gchar *filename );

/**

 * Retrieve the disc table of contents, and write it into the buffer in the 

 * format expected by the DC.

 * @return 0 on success, error code on failure (eg no disc mounted)

 */

gdrom_error_t gdrom_get_toc( char *buf );

/**

 * Retrieve the short (6-byte) session info, and write it into the buffer.

 * @return 0 on success, error code on failure.

 */

gdrom_error_t gdrom_get_info( char *buf, int session );

gdrom_track_t gdrom_get_track( int track_no );

uint8_t gdrom_get_track_no_by_lba( uint32_t lba );

/**

 * Shortcut to open and mount an image file

 */

gdrom_disc_t gdrom_mount_image( const gchar *filename );

void gdrom_mount_disc( gdrom_disc_t disc );

void gdrom_unmount_disc( void );

gboolean gdrom_is_mounted( void );

uint32_t gdrom_read_sectors( uint32_t sector, uint32_t sector_count,

			     int mode, char *buf, uint32_t *length );

#endif