/*
 * TwoWire.h - TWI/I2C library for Arduino Due
 * Copyright (c) 2011 Cristian Maglie <c.maglie@bug.st>.
 * All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifndef TwoWire_h
#define TwoWire_h

//#include <include/twi.h>

#include "Stream.h"
#include "variant.h"

#include "SERCOM.h"
#include "RingBuffer.h"

#define BUFFER_LENGTH 32


class TwoWire : public Stream
{
	public:
		TwoWire(SERCOM *s);
		void begin();
		void begin(uint8_t);

		void beginTransmission(uint8_t);
		uint8_t endTransmission(bool stopBit);
		uint8_t endTransmission(void);

		uint8_t requestFrom(uint8_t address, size_t quantity, bool stopBit);
		uint8_t requestFrom(uint8_t address, size_t quantity);

		size_t write(uint8_t data);
		size_t write(const uint8_t * data, size_t quantity);

		virtual int available(void);
		virtual int read(void);
		virtual int peek(void);
		virtual void flush(void);
		void onReceive(void(*)(int));
		void onRequest(void(*)(void));

		using Print::write;

		void onService(void);

	private:
		SERCOM * sercom;
		bool transmissionBegun;

		// RX Buffer
		RingBuffer rxBuffer;

		//TX buffer
		RingBuffer txBuffer;
		uint8_t txAddress;


		// Service buffer
		//uint8_t srvBuffer[BUFFER_LENGTH];
		//uint8_t srvBufferIndex;
		//uint8_t srvBufferLength;

		// Callback user functions
		void (*onRequestCallback)(void);
		void (*onReceiveCallback)(int);

		// TWI state
		//enum TwoWireStatus
    //{
		//	UNINITIALIZED,
		//	MASTER_IDLE,
		//	MASTER_SEND,
		//	MASTER_RECV,
		//	SLAVE_IDLE,
		//	SLAVE_RECV,
		//	SLAVE_SEND
		//};
		//TwoWireStatus status;

		// TWI clock frequency
		static const uint32_t TWI_CLOCK = 100000;

		// Timeouts
		//static const uint32_t RECV_TIMEOUT = 100000;
		//static const uint32_t XMIT_TIMEOUT = 100000;
};

extern TwoWire Wire;

#endif