/**

  * $Id$

  *

  * 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"

 #include <glib.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]

 /**

  * Track data type enumeration for cd images and devices. This somewhat

  * conflates the real track mode with the format of the image file, but

  * it manages to make sense so far.

  */

 typedef enum {

     GDROM_MODE0,          // Mode 0 - should never actually see this

 /* Data-only modes (image file contains only the user data) */

     GDROM_MODE1,          // Standard CD-Rom Mode 1 data track

     GDROM_MODE2_FORMLESS, // Mode 2 data track with no sub-structure (rare)

     GDROM_MODE2_FORM1,    // Mode 2/Form 1 data track (standard for multisession)

     GDROM_MODE2_FORM2,    // Mode 2/Form 2 data track (also fairly uncommon).

     GDROM_CDDA,           // Standard audio track

 /* This one is somewhat special - the image file contains the 2336 bytes of

  * "extended user data", which in turn contains either a form 1 or form 2

  * sector. In other words it's a raw mode2 XA sector without the 16-byte header.

  */

     GDROM_SEMIRAW_MODE2,

 /* Raw modes (image contains the full 2352-byte sector). Split into XA/Non-XA

  * here for convenience, although it's really a session level flag. */

     GDROM_RAW_XA,

     GDROM_RAW_NONXA,

 } gdrom_track_mode_t;

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

  * contains 0x06.

  */

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

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

 #define IDE_DISC_NONE  0x06

 #define IDE_DISC_AUDIO   0x00

 #define IDE_DISC_CDROM   0x10

 #define IDE_DISC_CDROMXA 0x20

 #define IDE_DISC_GDROM   0x80

 #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 */

     FILE *file;

 } *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, 

 				  unsigned 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, unsigned 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, unsigned 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, unsigned 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, uint32_t endlba);

     /**

      * 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 );

     const gchar *name; /* Device name / Image filename */

 } *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 */

     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 gdi_image_class;

 extern struct gdrom_image_class cdrom_device_class;

 /**

  * Construct a new image file using the default methods.

  */

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

 /**

  * Open an image file

  */

 gdrom_disc_t gdrom_image_open( const gchar *filename );

 /**

  * Dump image info

  */

 void gdrom_image_dump_info( gdrom_disc_t d );

 /**

  * Destroy an image data structure without closing the file

  * (Intended for use from image loaders only)

  */

 void gdrom_image_destroy_no_close( gdrom_disc_t d );

 /**

  * 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( unsigned 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( unsigned 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

  * @return true on success

  */

 gboolean gdrom_mount_image( const gchar *filename );

 void gdrom_mount_disc( gdrom_disc_t disc );

 void gdrom_unmount_disc( void );

 gboolean gdrom_is_mounted( void );

 gdrom_disc_t gdrom_get_current_disc();

 GList *gdrom_get_native_devices();

 uint32_t gdrom_read_sectors( uint32_t sector, uint32_t sector_count,

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

 /**

  * Given a base filename (eg for a .cue file), generate the path for the given

  * find_name relative to the original file. 

  * @return a newly allocated string.

  */

 gchar *gdrom_get_relative_filename( const gchar *base_name, const gchar *find_name );

 #endif