#ifndef MIDI_MIDIFILE_H
#define MIDI_MIDIFILE_H

/*
    MIDI Files definitions
    ---- ----- -----------

    This is based on the MIDI Files spec 1.0 from IMA.
*/

#ifndef EXEC_TYPES_H
#include <exec/types.h>
#endif


/* chunks */

#define MFCK_NULL 0L
#define MFCK_MThd (ULONG)'MThd'
#define MFCK_MTrk (ULONG)'MTrk'

struct ckhdr {	    /* always at the beginning of a chunk */
    ULONG id;	    /* id byte */
    LONG len;	    /* length of chunk in bytes (bytes after this header) */
};


/* header */

struct mfheader {   /* MIDI File header chunk */
    UWORD format;   /* format id */
    UWORD ntracks;  /* number of tracks */
    WORD division;  /* division if >0 is # of divisions per notated qtr note, <0 is SMPTE division (see spec) */
};

#define MFFMT_ONETRACK	 0	/* single track */
#define MFFMT_SIMTRACKS  1	/* multiple simultaneous tracks */
#define MFFMT_INDTRACKS  2	/* multiple temporally indepent single-track patterns */


/* track */

/*
    tracks consist of one or more events:

	<channel msg> | <sysex msg> | <meta event>

    <channel msg> uses running status so there may or may not be a
    status byte here

    <sysex msg>:  F0 len data
		  F7 len data
		  F7 len data F7
    where len is a variable length value.

    <meta event>:  FF type len data

    (see spec for more info)
*/


    /* special track event status bytes */
#define MS_ESCAPE    0xF7	/* either a sys/ex continuation or an "escape" sequence, tell apart using running status */
#define MS_META      0xFF	/* meta event */

    /* meta event types */
#define MFMETA_SEQNUM	  0x00	/* FF 00 02 ssss: ssss is a sequence number */
#define MFMETA_TEXT	  0x01	/* FF 01 len text: as are types 01 - 0F */
#define MFMETA_COPYRIGHT  0x02
#define MFMETA_TRACKNAME  0x03
#define MFMETA_INSTRNAME  0x04
#define MFMETA_LYRIC	  0x05
#define MFMETA_MARKER	  0x06
#define MFMETA_CUEPOINT   0x07
#define MFMETA_CHANPREFIX 0x20	/* FF 20 01 cc: Identifies channel for subsequent sys/ex and meta-events for track association */
#define MFMETA_TRACKEND   0x2f	/* FF 2F 00: denote the end of a track and is mandatory */
#define MFMETA_TEMPO	  0x51	/* FF 51 03 tttttt: set tempo in microseconds per MIDI qtr-note */
#define MFMETA_SMPTEOFFSET 0x54 /* FF 54 05 hr mn se fr ff: SMPTE offset */
#define MFMETA_TIMESIG	  0x58	/* FF 58 04 nn dd cc bb: uses struct timesig below */
#define MFMETA_KEYSIG	  0x59	/* FF 59 02 sf mi: key signature */
#define MFMETA_SEQSPEC	  0x7f	/* FF 7f len data: sequencer-specific meta-event */


struct mftimesig {	/* MIDI File time signature */
    UBYTE numerator;	/* numerator */
    UBYTE denompower;	/* negative power of two of denominator */
    UBYTE metronome;	/* number of midi clocks per metronome click */
    UBYTE division;	/* number of notated 32nd-notes per midi qtr note */
};

#define TEMPOLEN 3	/* current length of tempo change */

#endif