//
// Copyright (C) 2013-2016 Alexey Khokholov (Nuke.YKT)
//
// 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.
//
//
//  Nuked OPL3 emulator.
//  Thanks:
//      MAME Development Team(Jarek Burczynski, Tatsuyuki Satoh):
//          Feedback and Rhythm part calculation information.
//      forums.submarine.org.uk(carbon14, opl3):
//          Tremolo and phase generator calculation information.
//      OPLx decapsulated(Matthew Gambrell, Olli Niemitalo):
//          OPL2 ROMs.
//
// version: 1.7.1
//

#include <stdint.h>

typedef uint8_t Bit8u;
typedef int8_t Bit8s;
typedef uint16_t Bit16u;
typedef int16_t Bit16s;
typedef uint32_t Bit32u;
typedef int32_t Bit32s;
typedef uint64_t Bit64u;
typedef int64_t Bit64s;

typedef struct _opl3_slot opl3_slot;
typedef struct _opl3_channel opl3_channel;
typedef struct _opl3_chip opl3_chip;

struct _opl3_slot {
	opl3_channel *channel;
	opl3_chip *chip;
	Bit16s out;
	Bit16s fbmod;
	Bit16s *mod;
	Bit16s prout;
	Bit16s eg_rout;
	Bit16s eg_out;
	Bit8u eg_inc;
	Bit8u eg_gen;
	Bit8u eg_rate;
	Bit8u eg_ksl;
	Bit8u *trem;
	Bit8u reg_vib;
	Bit8u reg_type;
	Bit8u reg_ksr;
	Bit8u reg_mult;
	Bit8u reg_ksl;
	Bit8u reg_tl;
	Bit8u reg_ar;
	Bit8u reg_dr;
	Bit8u reg_sl;
	Bit8u reg_rr;
	Bit8u reg_wf;
	Bit8u key;
	Bit32u pg_phase;
	Bit32u timer;
};

struct _opl3_channel {
	opl3_slot *slots[2];
	opl3_channel *pair;
	opl3_chip *chip;
	Bit16s *out[4];
	Bit8u chtype;
	Bit16u f_num;
	Bit8u block;
	Bit8u fb;
	Bit8u con;
	Bit8u alg;
	Bit8u ksv;
	Bit16u cha, chb;
};

struct _opl3_chip {
	opl3_channel channel[18];
	opl3_slot slot[36];
	Bit16u timer;
	Bit8u newm;
	Bit8u extp;
	Bit8u panch;
	Bit8u nts;
	Bit8u rhy;
	Bit8u vibpos;
	Bit8u vibshift;
	Bit8u tremolo;
	Bit8u tremolopos;
	Bit8u tremoloshift;
	Bit32u noise;
	Bit16s zeromod;
	Bit32s mixbuff[2];
	// OPL3L
	Bit32s rateratio;
	Bit32s samplecnt;
	Bit16s oldsamples[2];
	Bit16s samples[2];
};

void OPL3_Generate(opl3_chip *chip, Bit16s *buf);
void OPL3_GenerateResampled(opl3_chip *chip, Bit16s *buf);
void OPL3_Reset(opl3_chip *chip, Bit32u samplerate);
void OPL3_WriteReg(opl3_chip *chip, Bit16u reg, Bit8u v);
