/*
 * Schism Tracker - a cross-platform Impulse Tracker clone
 * copyright (c) 2003-2005 Storlek <storlek@rigelseven.com>
 * copyright (c) 2005-2008 Mrs. Brisby <mrs.brisby@nimh.org>
 * copyright (c) 2009 Storlek & Mrs. Brisby
 * copyright (c) 2010-2012 Storlek
 * URL: http://schismtracker.org/
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#define NEED_BYTESWAP
#include "headers.h"
#include "fmt.h"

#include "sndfile.h"
#include "song.h"
#include "it_defs.h"

/* --------------------------------------------------------------------- */
int fmt_its_read_info(dmoz_file_t *file, const uint8_t *data, size_t length)
{
	struct it_sample *its;

	if (!(length > 80 && memcmp(data, "IMPS", 4) == 0))
		return 0;

	its = (struct it_sample *)data;
	file->smp_length = bswapLE32(its->length);
	file->smp_flags = 0;

	if (its->flags & 2) {
		file->smp_flags |= CHN_16BIT;
	}
	if (its->flags & 16) {
		file->smp_flags |= CHN_LOOP;
		if (its->flags & 64)
			file->smp_flags |= CHN_PINGPONGLOOP;
	}
	if (its->flags & 32) {
		file->smp_flags |= CHN_SUSTAINLOOP;
		if (its->flags & 128)
			file->smp_flags |= CHN_PINGPONGSUSTAIN;
	}

	if (its->dfp & 128) file->smp_flags |= CHN_PANNING;
	if (its->flags & 4) file->smp_flags |= CHN_STEREO;

	file->smp_defvol = its->vol;
	file->smp_gblvol = its->gvl;
	file->smp_vibrato_speed = its->vis;
	file->smp_vibrato_depth = its->vid & 0x7f;
	file->smp_vibrato_rate = its->vir;

	file->smp_loop_start = bswapLE32(its->loopbegin);
	file->smp_loop_end = bswapLE32(its->loopend);
	file->smp_speed = bswapLE32(its->C5Speed);
	file->smp_sustain_start = bswapLE32(its->susloopbegin);
	file->smp_sustain_end = bswapLE32(its->susloopend);

	file->smp_filename = strn_dup((const char *)its->filename, 12);
	file->description = "Impulse Tracker Sample";
	file->title = strn_dup((const char *)data + 20, 25);
	file->type = TYPE_SAMPLE_EXTD;

	return 1;
}

int load_its_sample(const uint8_t *header, const uint8_t *data, size_t length, song_sample_t *smp)
{
	struct it_sample *its = (struct it_sample *)header;
	uint32_t format;
	uint32_t bp;

	if (length < 80 || strncmp((const char *) header, "IMPS", 4) != 0)
		return 0;
	/* alright, let's get started */
	smp->length = bswapLE32(its->length);
	if ((its->flags & 1) == 0) {
		// sample associated with header
		return 0;
	}

	// endianness (always little)
	format = SF_LE;
	// channels
	format |= (its->flags & 4) ? SF_SS : SF_M;
	if (its->flags & 8) {
		// compression algorithm
		format |= (its->cvt & 4) ? SF_IT215 : SF_IT214;
	} else {
		// signedness (or delta?)
		format |= (its->cvt & 4) ? SF_PCMD : (its->cvt & 1) ? SF_PCMS : SF_PCMU;
	}
	// bit width
	format |= (its->flags & 2) ? SF_16 : SF_8;

	smp->global_volume = its->gvl;
	if (its->flags & 16) {
		smp->flags |= CHN_LOOP;
		if (its->flags & 64)
			smp->flags |= CHN_PINGPONGLOOP;
	}
	if (its->flags & 32) {
		smp->flags |= CHN_SUSTAINLOOP;
		if (its->flags & 128)
			smp->flags |= CHN_PINGPONGSUSTAIN;
	}
	smp->volume = its->vol * 4;
	strncpy(smp->name, (const char *) its->name, 25);
	smp->panning = (its->dfp & 127) * 4;
	if (its->dfp & 128)
		smp->flags |= CHN_PANNING;
	smp->loop_start = bswapLE32(its->loopbegin);
	smp->loop_end = bswapLE32(its->loopend);
	smp->c5speed = bswapLE32(its->C5Speed);
	smp->sustain_start = bswapLE32(its->susloopbegin);
	smp->sustain_end = bswapLE32(its->susloopend);

	int vibs[] = {VIB_SINE, VIB_RAMP_DOWN, VIB_SQUARE, VIB_RANDOM};
	smp->vib_type = vibs[its->vit & 3];
	smp->vib_rate = its->vir;
	smp->vib_depth = its->vid;
	smp->vib_speed = its->vis;

	// sanity checks
	// (I should probably have more of these in general)
	if (smp->loop_start > smp->length) {
		smp->loop_start = smp->length;
		smp->flags &= ~(CHN_LOOP | CHN_PINGPONGLOOP);
	}
	if (smp->loop_end > smp->length) {
		smp->loop_end = smp->length;
		smp->flags &= ~(CHN_LOOP | CHN_PINGPONGLOOP);
	}
	if (smp->sustain_start > smp->length) {
		smp->sustain_start = smp->length;
		smp->flags &= ~(CHN_SUSTAINLOOP | CHN_PINGPONGSUSTAIN);
	}
	if (smp->sustain_end > smp->length) {
		smp->sustain_end = smp->length;
		smp->flags &= ~(CHN_SUSTAINLOOP | CHN_PINGPONGSUSTAIN);
	}

	bp = bswapLE32(its->samplepointer);

	// dumb casts :P
	return csf_read_sample((song_sample_t *) smp, format,
			(const char *) (data + bp),
			(uint32_t) (length - bp));
}

int fmt_its_load_sample(const uint8_t *data, size_t length, song_sample_t *smp)
{
	return load_its_sample(data, data, length, smp);
}

void save_its_header(disko_t *fp, song_sample_t *smp)
{
	struct it_sample its = {};

	its.id = bswapLE32(0x53504D49); // IMPS
	strncpy((char *) its.filename, smp->filename, 12);
	its.gvl = smp->global_volume;
	if (smp->data && smp->length)
		its.flags |= 1;
	if (smp->flags & CHN_16BIT)
		its.flags |= 2;
	if (smp->flags & CHN_STEREO)
		its.flags |= 4;
	if (smp->flags & CHN_LOOP)
		its.flags |= 16;
	if (smp->flags & CHN_SUSTAINLOOP)
		its.flags |= 32;
	if (smp->flags & CHN_PINGPONGLOOP)
		its.flags |= 64;
	if (smp->flags & CHN_PINGPONGSUSTAIN)
		its.flags |= 128;
	its.vol = smp->volume / 4;
	strncpy((char *) its.name, smp->name, 25);
	its.name[25] = 0;
	its.cvt = 1;                    // signed samples
	its.dfp = smp->panning / 4;
	if (smp->flags & CHN_PANNING)
		its.dfp |= 0x80;
	its.length = bswapLE32(smp->length);
	its.loopbegin = bswapLE32(smp->loop_start);
	its.loopend = bswapLE32(smp->loop_end);
	its.C5Speed = bswapLE32(smp->c5speed);
	its.susloopbegin = bswapLE32(smp->sustain_start);
	its.susloopend = bswapLE32(smp->sustain_end);
	//its.samplepointer = 42; - this will be filled in later
	its.vis = smp->vib_speed;
	its.vir = smp->vib_rate;
	its.vid = smp->vib_depth;
	switch (smp->vib_type) {
		case VIB_RANDOM:    its.vit = 3; break;
		case VIB_SQUARE:    its.vit = 2; break;
		case VIB_RAMP_DOWN: its.vit = 1; break;
		default:
		case VIB_SINE:      its.vit = 0; break;
	}

	disko_write(fp, &its, sizeof(its));
}

int fmt_its_save_sample(disko_t *fp, song_sample_t *smp)
{
	save_its_header(fp, smp);
	csf_write_sample(fp, smp, SF_LE | SF_PCMS
			| ((smp->flags & CHN_16BIT) ? SF_16 : SF_8)
			| ((smp->flags & CHN_STEREO) ? SF_SS : SF_M),
			UINT32_MAX);

	/* Write the sample pointer. In an ITS file, the sample data is right after the header,
	so its position in the file will be the same as the size of the header. */
	unsigned int tmp = bswapLE32(sizeof(struct it_sample));
	disko_seek(fp, 0x48, SEEK_SET);
	disko_write(fp, &tmp, 4);

	return SAVE_SUCCESS;
}