/* Extended Module Player
 * Copyright (C) 1996-1999 Claudio Matsuoka and Hipolito Carraro Jr
 *
 * This file is part of the Extended Module Player and is distributed
 * under the terms of the GNU General Public License. See doc/COPYING
 * for more information.
 */

/* Based on the format description by FreeJack of The Elven Nation
 *
 * The loader recognizes four subformats:
 * - MAS_UTrack_V001: Ultra Tracker version < 1.4
 * - MAS_UTrack_V002: Ultra Tracker version 1.4
 * - MAS_UTrack_V003: Ultra Tracker version 1.5
 * - MAS_UTrack_V004: Ultra Tracker version 1.6
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "period.h"
#include "load.h"

#define KEEP_TONEPORTA 32	/* Rows to keep portamento effect */

struct ult_header {
    uint8 magic[15];		/* 'MAS_UTrack_V00x' */
    uint8 name[32];		/* Song name */
    uint8 msgsize;		/* ver < 1.4: zero */
} PACKED;

struct ult_header2 {
    uint8 order[256];		/* Orders */
    uint8 channels;		/* Number of channels - 1 */
    uint8 patterns;		/* Number of patterns - 1 */
} PACKED;

struct ult_instrument {
    uint8 name[32];		/* Instrument name */
    uint8 dosname[12];		/* DOS file name */
    uint32 loop_start;		/* Loop start */
    uint32 loopend;		/* Loop end */
    uint32 sizestart;		/* Sample size is sizeend - sizestart */
    uint32 sizeend;
    uint8 volume;		/* Volume (log; ver >= 1.4 linear) */
    uint8 bidiloop;		/* Sample loop flags */
    uint16 finetune;		/* Finetune */
    uint16 c2spd;		/* C2 frequency */
} PACKED;

struct ult_event {
    /* uint8 note; */
    uint8 ins;
    uint8 fxt;			/* MSN = fxt, LSN = f2t */
    uint8 f2p;			/* Secondary comes first -- little endian! */
    uint8 fxp;
} PACKED;


int ult_load (FILE * f)
{
    int i, j, k, ver, cnt;
    struct xxm_event *event;
    struct ult_header ufh;
    struct ult_header2 ufh2;
    struct ult_instrument uih;
    struct ult_event ue;
    int keep_porta1 = 0, keep_porta2 = 0;
    uint8 x8;

    LOAD_INIT ();

    fread (&ufh, 1, sizeof (ufh), f);
    if (strncmp ((char *) ufh.magic, "MAS_UTrack_V000", 14))
	return -1;

    ver = ufh.magic[14] - '0';
    strncpy (xmp_ctl->name, ufh.name, 32);
    ufh.name[0] = 0;
    sprintf (xmp_ctl->type, "Ultra Tracker V%04d", ver);

    MODULE_INFO ();

    fseek (f, ufh.msgsize * 32, SEEK_CUR);

    fread (&x8, 1, 1, f);
    xxh->ins = xxh->smp = x8;
    /* xxh->flg |= XXM_FLG_LINEAR; */

    /* Read and convert instruments */

    INSTRUMENT_INIT ();

    if (V (1))
	report ("Instruments    : %d ", xxh->ins);

    for (i = 0; i < xxh->ins; i++) {
	xxi[i] = calloc (sizeof (struct xxm_instrument), 1);
	uih.c2spd = 0;
	fread (&uih, 1, sizeof (uih) - 2 * (ver < 4), f);
	L_ENDIAN32 (uih.loop_start);
	L_ENDIAN32 (uih.loopend);
	L_ENDIAN32 (uih.sizestart);
	L_ENDIAN32 (uih.sizeend);
	L_ENDIAN32 (uih.finetune);
	L_ENDIAN32 (uih.c2spd);
	if (ver > 3) {			/* Incorrect in ult_form.txt */
	    uih.c2spd ^= uih.finetune;
	    uih.finetune ^= uih.c2spd;
	    uih.c2spd ^= uih.finetune;
	}
	xxih[i].nsm = !!(xxs[i].len = uih.sizeend - uih.sizestart);
	xxs[i].lps = uih.loop_start;
	xxs[i].lpe = uih.loopend;

	/* Claudio's note: I'm ignoring reverse playback for samples */
	switch (uih.bidiloop) {
	case 4:
	    xxs[i].flg = WAVE_16_BITS;
	    xxs[i].len <<= 1;
	    break;
	case 8:
	case 24:
	    xxs[i].flg = WAVE_LOOPING;
	    break;
	case 12:
	case 28:
	    xxs[i].flg = WAVE_16_BITS | WAVE_LOOPING;
	    xxs[i].len <<= 1;
	    break;
	}

/* TODO: Add logarithmic volume support */
	xxi[i][0].vol = uih.volume;
	xxi[i][0].pan = 0x80;
	xxi[i][0].sid = i;
	strncpy ((char *) xxih[i].name, uih.name, 24);
	uih.dosname[0] = 0;
	str_adj ((char *) uih.name);
	if ((V (1)) && (strlen ((char *) uih.name) || xxs[i].len)) {
	    report ("\n[%2X] %-32.32s %05x%c%05x %05x %c V%02x F%04x %5d",
		i, uih.name, xxs[i].len,
		xxs[i].flg & WAVE_16_BITS ? '+' : ' ',
		xxs[i].lps, xxs[i].lpe,
		xxs[i].flg & WAVE_LOOPING ? 'L' : ' ',
		xxi[i][0].vol, uih.finetune, uih.c2spd);
	}

	if (ver > 3)
	    c2spd_to_note (uih.c2spd, &xxi[i][0].xpo, &xxi[i][0].fin);
    }

    if (V (1))
	report ("\n");

    fread (&ufh2, 1, sizeof (ufh2), f);
    for (i = 0; i < 256; i++) {
	if (ufh2.order[i] == 0xff)
	    break;
	xxo[i] = ufh2.order[i];
    }
    xxh->len = i;
    xxh->chn = ufh2.channels + 1;
    xxh->pat = ufh2.patterns + 1;
    xxh->tpo = 6;
    xxh->bpm = 125;
    xxh->trk = xxh->chn * xxh->pat;

    for (i = 0; i < xxh->chn; i++) {
	if (ver >= 3) {
	    fread (&x8, 1, 1, f);
	    xxc[i].pan = 255 * x8 / 15;
	} else {
	    xxc[i].pan = (((i + 1) / 2) % 2) * 0xff;	/* ??? */
	}
    }

    PATTERN_INIT ();

    /* Read and convert patterns */

    if (V (0))
	report ("Stored patterns: %d ", xxh->pat);

    /* Events are stored by channel */
    for (i = 0; i < xxh->pat; i++) {
	PATTERN_ALLOC (i);
	xxp[i]->rows = 64;
	TRACK_ALLOC (i);
    }

    for (i = 0; i < xxh->chn; i++) {
	for (j = 0; j < 64 * xxh->pat; ) {
	    cnt = 1;
	    fread (&x8, 1, 1, f);	/* Read note or repeat code (0xfc) */
	    if (x8 == 0xfc) {
		fread (&x8, 1, 1, f);		/* Read repeat count */
		cnt = x8;
		fread (&x8, 1, 1, f);		/* Read note */
	    }
	    fread (&ue, 4, 1, f);		/* Read rest of the event */

	    if (cnt == 0)
		cnt++;

	    for (k = 0; k < cnt; k++, j++) {
		event = &EVENT (j >> 6, i , j & 0x3f);
		memset (event, 0, sizeof (struct xxm_event));
		if (x8)
		    event->note = x8 + 24;
		event->ins = ue.ins;
		event->fxt = MSN (ue.fxt);
		event->f2t = LSN (ue.fxt);
		event->fxp = ue.fxp;
		event->f2p = ue.f2p;

		switch (event->fxt) {
		case 0x00:		/* <mumble> */
		    if (event->fxp)
			keep_porta1 = 0;
		    if (keep_porta1) {
			event->fxt = 0x03;
			keep_porta1--;
		    }
		    break;
		case 0x03:		/* Portamento kludge */
		    keep_porta1 = KEEP_TONEPORTA;
		    break;
		case 0x05:		/* 'Special' effect */
		case 0x06:		/* Reserved */
		    event->fxt = event->fxp = 0;
		    break;
		case 0x0b:		/* Pan */
		    event->fxt = FX_SETPAN;
		    event->fxp <<= 4;
		    break;
		case 0x09:		/* Sample offset */
/* TODO: fine sample offset */
		    event->fxp <<= 2;
		    break;
		}

		switch (event->f2t) {
		case 0x00:		/* <mumble> */
		    if (event->f2p)
			keep_porta2 = 0;
		    if (keep_porta2) {
			event->f2t = 0x03;
			keep_porta2--;
		    }
		    break;
		case 0x03:		/* Portamento kludge */
		    keep_porta2 = KEEP_TONEPORTA;
		    break;
		case 0x05:		/* 'Special' effect */
		case 0x06:		/* Reserved */
		    event->f2t = event->f2p = 0;
		    break;
		case 0x0b:		/* Pan */
		    event->f2t = FX_SETPAN;
		    event->f2p <<= 4;
		    break;
		case 0x09:		/* Sample offset */
/* TODO: fine sample offset */
		    event->f2p <<= 2;
		    break;
		}

	    }
	    if (V (0) && (j % (64 * xxh->chn) == 0))
		report (".");
	}
    }

    if (V (0))
	report ("\nStored samples : %d ", xxh->smp);

    for (i = 0; i < xxh->ins; i++) {
	if (!xxs[i].len)
	    continue;
	xmp_drv_loadpatch (f, xxi[i][0].sid, xmp_ctl->c4rate, 0, &xxs[i], NULL);
	if (V (0))
	    report (".");
    }
    if (V (0))
	report ("\n");

    xmp_ctl->volbase = 0x100;

    return 0;
}