// license:BSD-3-Clause
// copyright-holders:R. Belmont, Olivier Galibert
/*********************************************************************

    formats/esq8_dsk.c

    Formats for 8-bit Ensoniq synthesizers and samplers

    Disk is PC MFM, 40 tracks, single (Mirage) or double (SQ-80) sided,
    with 6 sectors per track.
    Sectors 0-4 are 1024 bytes, sector 5 is 512 bytes

*********************************************************************/

#include "esq8_dsk.h"

#include "ioprocs.h"

#include "osdcore.h" // osd_printf_*


const floppy_image_format_t::desc_e esq8img_format::esq_6_desc[] = {
	{ MFM, 0x4e, 80 },
	{ MFM, 0x00, 12 },
	{ RAW, 0x5224, 3 },
	{ MFM, 0xfc, 1 },
	{ MFM, 0x4e, 50 },
	{ MFM, 0x00, 12 },
	{ SECTOR_LOOP_START, 0, 5 },
	{   CRC_CCITT_START, 1 },
	{     RAW, 0x4489, 3 },
	{     MFM, 0xfe, 1 },
	{     TRACK_ID },
	{     HEAD_ID },
	{     SECTOR_ID },
	{     SIZE_ID },
	{   CRC_END, 1 },
	{   CRC, 1 },
	{   MFM, 0x4e, 22 },
	{   MFM, 0x00, 12 },
	{   CRC_CCITT_START, 2 },
	{     RAW, 0x4489, 3 },
	{     MFM, 0xfb, 1 },
	{     SECTOR_DATA, -1 },
	{   CRC_END, 2 },
	{   CRC, 2 },
	{   MFM, 0x4e, 84 },
	{   MFM, 0x00, 12 },
	{ SECTOR_LOOP_END },
	{ MFM, 0x4e, 170 },
	{ END }
};

esq8img_format::esq8img_format()
{
}

const char *esq8img_format::name() const
{
	return "esq8";
}

const char *esq8img_format::description() const
{
	return "Ensoniq Mirage/SQ-80 floppy disk image";
}

const char *esq8img_format::extensions() const
{
	return "img";
}

bool esq8img_format::supports_save() const
{
	return true;
}

void esq8img_format::find_size(util::random_read &io, int &track_count, int &head_count, int &sector_count)
{
	uint64_t size;
	if(!io.length(size))
	{
		track_count = 80;
		head_count = 1;
		sector_count = 6;

		if(size == 5632 * 80)
		{
			return;
		}
	}
	track_count = head_count = sector_count = 0;
}

int esq8img_format::identify(util::random_read &io, uint32_t form_factor, const std::vector<uint32_t> &variants)
{
	int track_count, head_count, sector_count;
	find_size(io, track_count, head_count, sector_count);

	if(track_count)
		return 50;

	return 0;
}

bool esq8img_format::load(util::random_read &io, uint32_t form_factor, const std::vector<uint32_t> &variants, floppy_image *image)
{
	int track_count, head_count, sector_count;
	find_size(io, track_count, head_count, sector_count);

	uint8_t sectdata[(5*1024) + 512];
	desc_s sectors[6];
	for(int i=0; i<sector_count; i++)
	{
		if(i < 5)
		{
			sectors[i].data = sectdata + (1024*i);  // 5 1024 byte sectors
			sectors[i].size = 1024;
			sectors[i].sector_id = i;
		}
		else
		{
			sectors[i].data = sectdata + (5*1024);  // 1 512 byte sector
			sectors[i].size = 512;
			sectors[i].sector_id = i;
		}
	}

	int track_size = (5*1024) + 512;

	for(int track=0; track < track_count; track++)
	{
		for(int head=0; head < head_count; head++)
		{
			size_t actual;
			io.read_at((track*head_count + head)*track_size, sectdata, track_size, actual);
			generate_track(esq_6_desc, track, head, sectors, sector_count, 109376, image);
		}
	}

	image->set_variant(floppy_image::DSDD);

	return true;
}

bool esq8img_format::save(util::random_read_write &io, const std::vector<uint32_t> &variants, floppy_image *image)
{
	uint64_t file_offset = 0;
	int track_count, head_count, sector_count;
	get_geometry_mfm_pc(image, 2000, track_count, head_count, sector_count);

	if(track_count != 80)
		track_count = 80;

	// Happens for a fully unformatted floppy
	if(!head_count)
		head_count = 1;

	if(sector_count != 6)
		sector_count = 6;

	for(int track=0; track < track_count; track++)
	{
		for(int head=0; head < head_count; head++)
		{
			auto bitstream = generate_bitstream_from_track(track, head, 2000, image);
			auto sectors = extract_sectors_from_bitstream_mfm_pc(bitstream);
			int sector_expected_size;

			for(int sector = 0; sector < sector_count; sector++)
			{
				if(sector < 5)
					sector_expected_size = 1024;
				else
					sector_expected_size = 512;

				if(sectors[sector].size() != sector_expected_size)
				{
					osd_printf_error("esq8img_format: track %d, sector %d invalid size: %d\n", track, sector, sectors[sector].size());
					return false;
				}

				size_t actual;
				io.write_at(file_offset, sectors[sector].data(), sector_expected_size, actual);
				file_offset += sector_expected_size;
			}
		}
	}

	return true;
}

const floppy_format_type FLOPPY_ESQ8IMG_FORMAT = &floppy_image_format_creator<esq8img_format>;
