/*
 *  Copyright (C) 2002-2021  The DOSBox Team
 *
 *  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.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */


// include guard
#ifndef DOSBOX_DIRECTSERIAL_WIN32_H
#define DOSBOX_DIRECTSERIAL_WIN32_H

#include "dosbox.h"

#if C_DIRECTSERIAL

#define DIRECTSERIAL_AVAILIBLE
#include "serialport.h"

#include "libserial.h"

class CDirectSerial : public CSerial {
public:
	CDirectSerial(Bitu id, CommandLine* cmd);
	~CDirectSerial();

	void updatePortConfig(uint16_t divider, uint8_t lcr) override;
	void updateMSR() override;
	void transmitByte(uint8_t val, bool first) override;
	void setBreak(bool value) override;
	
	void setRTSDTR(bool rts, bool dtr) override;
	void setRTS(bool val) override;
	void setDTR(bool val) override;
	void handleUpperEvent(uint16_t type) override;

private:
	COMPORT comport;

	Bitu rx_state = 0;
#define D_RX_IDLE		0
#define D_RX_WAIT		1
#define D_RX_BLOCKED	2
#define D_RX_FASTWAIT	3

	Bitu rx_retry;		// counter of retries (every millisecond)
	Bitu rx_retry_max;	// how many POLL_EVENTS to wait before causing
						// an overrun error.
	// Host-port receive polling tick in milliseconds (default 1.0).
	// Latency-critical hardware (VWE RIO cockpit board: drops comms when an
	// ACK is late by a few ms) needs incoming bytes discovered faster than
	// the stock 1ms tick; configurable via "rxpollus:<microseconds>".
	float rx_poll_ms = 1.0f;
	// Burst-delivery divisor ("rxburst:<n>"). Stock DOSBox re-serializes
	// received bytes at emulated wire speed (bytetime per byte) even though
	// they already paid their wire time on the physical cable and are
	// sitting in the host buffer. n>1 delivers buffered bytes n times
	// faster, cutting multi-byte reply latency (RIO analog packets).
	float rx_burst_div = 1.0f;
	// RIO_TAP=<path> (host env): wire-level byte log ("<host-us> <emu-ms>
	// T|R <hex>") to verify whether RIO requests reach the wire and when
	// replies come back. NULL when disabled.
	FILE *tap_fp = nullptr;
	double tap_t0_us = 0.0;
	void tapLine(char dir, unsigned val, unsigned err);
	bool doReceive();

#if SERIAL_DEBUG
	bool dbgmsg_poll_block = false;
	bool dbgmsg_rx_block = false;
#endif

};

#endif	// C_DIRECTSERIAL
#endif	// include guard