// license:GPL-2.0+
// copyright-holders:Jarek Burczynski
#ifndef MAME_SOUND_YMDELTAT_H
#define MAME_SOUND_YMDELTAT_H

#pragma once
#include "emu.h"

typedef uint8_t (*FM_READBYTE)(device_t *device, offs_t offset);
typedef void (*FM_WRITEBYTE)(device_t *device, offs_t offset, uint8_t data);
typedef void (*STATUS_CHANGE_HANDLER)(void *chip, uint8_t status_bits);


/* DELTA-T (adpcm type B) struct */
struct YM_DELTAT {/* AT: rearranged and tightened structure */
	enum
	{
		EMULATION_MODE_NORMAL = 0,
		EMULATION_MODE_YM2610 = 1
	};

	FM_READBYTE read_byte;
	FM_WRITEBYTE write_byte;
	int32_t   *output_pointer;/* pointer of output pointers   */
	int32_t   *pan;           /* pan : &output_pointer[pan]   */
	double  freqbase;
#if 0
	double  write_time;     /* Y8950: 10 cycles of main clock; YM2608: 20 cycles of main clock */
	double  read_time;      /* Y8950: 8 cycles of main clock;  YM2608: 18 cycles of main clock */
#endif
	uint32_t  memory_size;
	int     output_range;
	uint32_t  now_addr;       /* current address      */
	uint32_t  now_step;       /* correct step         */
	uint32_t  step;           /* step                 */
	uint32_t  start;          /* start address        */
	uint32_t  limit;          /* limit address        */
	uint32_t  end;            /* end address          */
	uint32_t  delta;          /* delta scale          */
	int32_t   volume;         /* current volume       */
	int32_t   acc;            /* shift Measurement value*/
	int32_t   adpcmd;         /* next Forecast        */
	int32_t   adpcml;         /* current value        */
	int32_t   prev_acc;       /* leveling value       */
	uint8_t   now_data;       /* current rom data     */
	uint8_t   CPU_data;       /* current data from reg 08 */
	uint8_t   portstate;      /* port status          */
	uint8_t   control2;       /* control reg: SAMPLE, DA/AD, RAM TYPE (x8bit / x1bit), ROM/RAM */
	uint8_t   portshift;      /* address bits shift-left:
	                        ** 8 for YM2610,
	                        ** 5 for Y8950 and YM2608 */

	uint8_t   DRAMportshift;  /* address bits shift-right:
	                        ** 0 for ROM and x8bit DRAMs,
	                        ** 3 for x1 DRAMs */

	uint8_t   memread;        /* needed for reading/writing external memory */

	/* handlers and parameters for the status flags support */
	STATUS_CHANGE_HANDLER   status_set_handler;
	STATUS_CHANGE_HANDLER   status_reset_handler;

	/* note that different chips have these flags on different
	** bits of the status register
	*/
	void *  status_change_which_chip;   /* this chip id */
	uint8_t   status_change_EOS_bit;      /* 1 on End Of Sample (record/playback/cycle time of AD/DA converting has passed)*/
	uint8_t   status_change_BRDY_bit;     /* 1 after recording 2 datas (2x4bits) or after reading/writing 1 data */
	uint8_t   status_change_ZERO_bit;     /* 1 if silence lasts for more than 290 milliseconds on ADPCM recording */

	/* neither Y8950 nor YM2608 can generate IRQ when PCMBSY bit changes, so instead of above,
	** the statusflag gets ORed with PCM_BSY (below) (on each read of statusflag of Y8950 and YM2608)
	*/
	uint8_t   PCM_BSY;        /* 1 when ADPCM is playing; Y8950/YM2608 only */

	uint8_t   reg[16];        /* adpcm registers      */
	uint8_t   emulation_mode; /* which chip we're emulating */
	device_t *device;

	/*void BRDY_callback();*/

	uint8_t ADPCM_Read();
	void ADPCM_Write(int r, int v);
	void ADPCM_Reset(int panidx, int mode, device_t *dev);
	void ADPCM_CALC();

	void postload(uint8_t *regs);
	void savestate(device_t *device);
};

#endif // MAME_SOUND_YMDELTAT_H