/* Copyright (c) 2011, Peter Barrett  
**  
** Permission to use, copy, modify, and/or distribute this software for  
** any purpose with or without fee is hereby granted, provided that the  
** above copyright notice and this permission notice appear in all copies.  
** 
** THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL  
** WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED  
** WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR  
** BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES  
** OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,  
** WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,  
** ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS  
** SOFTWARE.  
*/

#include "Platform.h"
#include "USBAPI.h"
#include <avr/wdt.h>

#if defined(USBCON)
#ifdef CDC_ENABLED

/*
#if (RAMEND < 1000)
#define SERIAL_BUFFER_SIZE 16
#else
#define SERIAL_BUFFER_SIZE 64
#endif

struct ring_buffer
{
	unsigned char buffer[SERIAL_BUFFER_SIZE];
	volatile int head;
	volatile int tail;
};

ring_buffer cdc_rx_buffer = { { 0 }, 0, 0};

// -- deplace dans le .h

typedef struct
{
	u32	dwDTERate;
	u8	bCharFormat;
	u8 	bParityType;
	u8 	bDataBits;
	u8	lineState;
} LineInfo;
*/
LineInfo _usbLineInfo = { 57600, 0x00, 0x00, 0x00, 0x00 };

#define WEAK __attribute__ ((weak))

extern const CDCDescriptor _cdcInterface PROGMEM;
const CDCDescriptor _cdcInterface =
{
	D_IAD(0,2,CDC_COMMUNICATION_INTERFACE_CLASS,CDC_ABSTRACT_CONTROL_MODEL,1),

	//	CDC communication interface
	D_INTERFACE(CDC_ACM_INTERFACE,1,CDC_COMMUNICATION_INTERFACE_CLASS,CDC_ABSTRACT_CONTROL_MODEL,0),
	D_CDCCS(CDC_HEADER,0x10,0x01),								// Header (1.10 bcd)
	D_CDCCS(CDC_CALL_MANAGEMENT,1,1),							// Device handles call management (not)
	D_CDCCS4(CDC_ABSTRACT_CONTROL_MANAGEMENT,6),				// SET_LINE_CODING, GET_LINE_CODING, SET_CONTROL_LINE_STATE supported
	D_CDCCS(CDC_UNION,CDC_ACM_INTERFACE,CDC_DATA_INTERFACE),	// Communication interface is master, data interface is slave 0
	D_ENDPOINT(USB_ENDPOINT_IN (CDC_ENDPOINT_ACM),USB_ENDPOINT_TYPE_INTERRUPT,0x10,0x40),

	//	CDC data interface
	D_INTERFACE(CDC_DATA_INTERFACE,2,CDC_DATA_INTERFACE_CLASS,0,0),
	D_ENDPOINT(USB_ENDPOINT_OUT(CDC_ENDPOINT_OUT),USB_ENDPOINT_TYPE_BULK,0x40,0),
	D_ENDPOINT(USB_ENDPOINT_IN (CDC_ENDPOINT_IN ),USB_ENDPOINT_TYPE_BULK,0x40,0)
};

int WEAK CDC_GetInterface(u8* interfaceNum)
{
	interfaceNum[0] += 2;	// uses 2
	return USB_SendControl(TRANSFER_PGM,&_cdcInterface,sizeof(_cdcInterface));
}

bool WEAK CDC_Setup(Setup& setup)
{
	u8 r = setup.bRequest;
	u8 requestType = setup.bmRequestType;

	if (REQUEST_DEVICETOHOST_CLASS_INTERFACE == requestType)
	{
		if (CDC_GET_LINE_CODING == r)
		{
			USB_SendControl(0,(void*)&_usbLineInfo,7);
			return true;
		}
	}

	if (REQUEST_HOSTTODEVICE_CLASS_INTERFACE == requestType)
	{
		if (CDC_SET_LINE_CODING == r)
		{
			USB_RecvControl((void*)&_usbLineInfo,7);
			return true;
		}

		if (CDC_SET_CONTROL_LINE_STATE == r)
		{
			_usbLineInfo.lineState = setup.wValueL;

			// auto-reset into the bootloader is triggered when the port, already 
			// open at 1200 bps, is closed.  this is the signal to start the watchdog
			// with a relatively long period so it can finish housekeeping tasks
			// like servicing endpoints before the sketch ends
			if (1200 == _usbLineInfo.dwDTERate) {
				// We check DTR state to determine if host port is open (bit 0 of lineState).
				if ((_usbLineInfo.lineState & 0x01) == 0) {
					*(uint16_t *)0x0800 = 0x7777;
					wdt_enable(WDTO_120MS);
				} else {
					// Most OSs do some intermediate steps when configuring ports and DTR can
					// twiggle more than once before stabilizing.
					// To avoid spurious resets we set the watchdog to 250ms and eventually
					// cancel if DTR goes back high.
	
					wdt_disable();
					wdt_reset();
					*(uint16_t *)0x0800 = 0x0;
				}
			}
			return true;
		}
	}
	return false;
}

/*
int _serialPeek = -1;
void Serial_::begin(uint16_t baud_count)
{
}

void Serial_::end(void)
{
}

void WEAK CDC_accept(void)
{
	Serial.accept();
}

void Serial_::accept(void) 
{
	ring_buffer *buffer = &cdc_rx_buffer;
	int c = USB_Recv(CDC_RX); 
	int i = (unsigned int)(buffer->head+1) % SERIAL_BUFFER_SIZE;
	
	// if we should be storing the received character into the location
	// just before the tail (meaning that the head would advance to the
	// current location of the tail), we're about to overflow the buffer
	// and so we don't write the character or advance the head.
	if (i != buffer->tail) {
		buffer->buffer[buffer->head] = c;
		buffer->head = i;
	}
}

int Serial_::available(void)
{
	ring_buffer *buffer = &cdc_rx_buffer;
	return (unsigned int)(SERIAL_BUFFER_SIZE + buffer->head - buffer->tail) % SERIAL_BUFFER_SIZE;
}

int Serial_::peek(void)
{
	ring_buffer *buffer = &cdc_rx_buffer;
	if (buffer->head == buffer->tail) {
		return -1;
	} else {
		return buffer->buffer[buffer->tail];
	}
}

int Serial_::read(void)
{
	ring_buffer *buffer = &cdc_rx_buffer;
	// if the head isn't ahead of the tail, we don't have any characters
	if (buffer->head == buffer->tail) {
		return -1;
	} else {
		unsigned char c = buffer->buffer[buffer->tail];
		buffer->tail = (unsigned int)(buffer->tail + 1) % SERIAL_BUFFER_SIZE;
		return c;
	}	
}

void Serial_::flush(void)
{
	USB_Flush(CDC_TX);
}

size_t Serial_::write(uint8_t c)
{

	
	// TODO - ZE - check behavior on different OSes and test what happens if an
	// open connection isn't broken cleanly (cable is yanked out, host dies
	// or locks up, or host virtual serial port hangs)
	if (_usbLineInfo.lineState > 0)	{
		int r = USB_Send(CDC_TX,&c,1);
		if (r > 0) {
			return r;
		} else {
			setWriteError();
			return 0;
		}
	}
	setWriteError();
	return 0;
}

// This operator is a convenient way for a sketch to check whether the
// port has actually been configured and opened by the host (as opposed
// to just being connected to the host).  It can be used, for example, in 
// setup() before printing to ensure that an application on the host is
// actually ready to receive and display the data.
// We add a short delay before returning to fix a bug observed by Federico
// where the port is configured (lineState != 0) but not quite opened.
Serial_::operator bool() {
	bool result = false;
	if (_usbLineInfo.lineState > 0) 
		result = true;
	delay(10);
	return result;
}

Serial_ Serial;
*/
#endif
#endif /* if defined(USBCON) */