/**

 * $Id$

 *

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

 * disc drivers. (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 lxdream_gddriver_H

#define lxdream_gddriver_H 1

#include <stdio.h>

#include "lxdream.h"

#include "gdrom/gdrom.h"

#include <glib/gstrfuncs.h>

#ifdef __cplusplus

extern "C" {

#endif

#define MAX_SECTOR_SIZE 2352

#define CD_MSF_START 150 /* MSF numbering starts after the initial pregap */

#define CD_FRAMES_PER_SECOND 75

#define CD_SECONDS_PER_MINUTE 60

#define CD_FRAMES_PER_MINUTE (CD_FRAMES_PER_SECOND*CD_SECONDS_PER_MINUTE)

#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;           /* Per-track file handle (if any) */

} *gdrom_track_t;

struct gdrom_disc {

    int disc_type;     /* One of the IDE_DISC_* flags */

    const gchar *name; /* Device name / Image filename (owned) */

    const gchar *display_name; /* User-friendly device name, if any (owned) */

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

    char title[129]; /* Disc title (if any) from bootstrap */

    int track_count;

    struct gdrom_track track[99];

    FILE *file;       /* Image file / device handle */

    void *impl_data; /* Implementation private data */

	/* Check for media change. If the media cannot change (ie image file)

	 * or is notified asynchonously, this should be a no-op. In the event of

	 * a change, this function should update the structure according to the

	 * new media (including TOC), and return TRUE.

	 * @return TRUE if the media has changed since the last check, otherwise

	 * FALSE.

	 */

	gboolean (*check_status)( struct gdrom_disc *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 );

    /**

     * 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);

	/**

	 * Stop audio playback

	 */

	gdrom_error_t (*stop_audio)(struct gdrom_disc *disc);

    /**

     * 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 );

	/**

	 * Release all memory and system resources, including the gdrom_disc itself.

	 * (implicitly calls close() if not already closed. 

	 * @param disc The disc to destroy

	 * @param close_fh if TRUE, close the main file/device, otherwise leave open.

	 * This is mainly used when the handle will be immediately reused.

	 */

    void (*destroy)( struct gdrom_disc *disc, gboolean close_fh );

};

/**

 * Low-level SCSI transport provided to the main SCSI/MMC driver. When used

 * this will be set as the disc->impl_data field.

 * Note: For symmetry there should be a packet_write variant, but we don't

 * currently need it for anything. YAGNI, etc.

 */

typedef struct gdrom_scsi_transport {

	/* Execute a read command (ie a command that returns a block of data in

	 * response, not necessarily a CD read). 

	 * @param scsi The disc to execute the command

	 * @param cmd  The 12-byte command packet

	 * @param buf  The buffer to receive the read results

	 * @param length On entry, the size of buf. Modified on exit to the number

	 *        of bytes actually read.

	 * @return PKT_ERR_OK on success, otherwise the host error code.

	 */

	gdrom_error_t (*packet_read)( struct gdrom_disc *disc,

	                              char *cmd, unsigned char *buf,

	                              unsigned int *length );

	/* Execute a generic command that does not write or return any data.

	 * (eg play audio).

	 * @param scsi The disc to execute the command

	 * @param cmd  The 12-byte command packet

	 * @return PKT_ERR_OK on success, otherwise the host error code.

	 */

	gdrom_error_t (*packet_cmd)( struct gdrom_disc *disc,

	                             char *cmd );

	/* Return TRUE if the media has changed since the last call, otherwise

	 * FALSE. This method is used to implement the disc-level check_status

	 * and should have no side-effects.

	 */

	gboolean (*media_changed)( struct gdrom_disc *disc );

} *gdrom_scsi_transport_t;

/**

 * Allocate a new gdrom_disc_t and initialize the filename and file fields.

 * The disc is otherwise uninitialized - this is an internal method for use 

 * by the concrete implementations.

 */

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

/**

 * Construct a new SCSI/MMC disc using the supplied transport implementation.

 */

gdrom_disc_t gdrom_scsi_disc_new(const gchar *filename, FILE *f, gdrom_scsi_transport_t transport);

/**

 * Construct a new image file using the default methods.

 */

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

#define SCSI_TRANSPORT(disc)  ((gdrom_scsi_transport_t)disc->impl_data)

/**

 *

 */

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;

/**

 * Determine the track number containing the specified sector by lba.

 */

int gdrom_disc_get_track_by_lba( gdrom_disc_t image, uint32_t lba );

/**

 * Default disc destroy method, for chaining from subclasses

 */

void gdrom_disc_destroy( gdrom_disc_t disc, gboolean close_fh );

gdrom_device_t gdrom_device_new( const gchar *name, const gchar *dev_name );

void gdrom_device_destroy( gdrom_device_t dev );

/************* Host-native support functions ***************/

/**

 * Given a raw (2352 byte) data sector, extract the requested components into the 

 * target buffer. length will also be updated with the length of the copied

 * data

 */

void gdrom_extract_raw_data_sector( char *sector_data, int mode, unsigned char *buf, uint32_t *length );

/**

 * Check the disc for a useable DC bootstrap, and update the disc

 * with the title accordingly.

 * @return TRUE if we found a bootstrap, otherwise FALSE.

 */

gboolean gdrom_disc_read_title( gdrom_disc_t disc ); 

/** 

 * Parse a TOC mode-2 result buffer into the gdrom_disc_t data structure

 */

void mmc_parse_toc2( gdrom_disc_t disc, unsigned char *buf );

/**

 * Set the disc type flag based on the track contents

 */

void gdrom_set_disc_type( gdrom_disc_t disc );

#endif /* !lxdream_gddriver_H */