/*
    FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd.
    All rights reserved

    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

    This file is part of the FreeRTOS distribution.

    FreeRTOS is free software; you can redistribute it and/or modify it under
    the terms of the GNU General Public License (version 2) as published by the
    Free Software Foundation >>>> AND MODIFIED BY <<<< the FreeRTOS exception.

    ***************************************************************************
    >>!   NOTE: The modification to the GPL is included to allow you to     !<<
    >>!   distribute a combined work that includes FreeRTOS without being   !<<
    >>!   obliged to provide the source code for proprietary components     !<<
    >>!   outside of the FreeRTOS kernel.                                   !<<
    ***************************************************************************

    FreeRTOS 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.  Full license text is available on the following
    link: http://www.freertos.org/a00114.html

    ***************************************************************************
     *                                                                       *
     *    FreeRTOS provides completely free yet professionally developed,    *
     *    robust, strictly quality controlled, supported, and cross          *
     *    platform software that is more than just the market leader, it     *
     *    is the industry's de facto standard.                               *
     *                                                                       *
     *    Help yourself get started quickly while simultaneously helping     *
     *    to support the FreeRTOS project by purchasing a FreeRTOS           *
     *    tutorial book, reference manual, or both:                          *
     *    http://www.FreeRTOS.org/Documentation                              *
     *                                                                       *
    ***************************************************************************

    http://www.FreeRTOS.org/FAQHelp.html - Having a problem?  Start by reading
    the FAQ page "My application does not run, what could be wrong?".  Have you
    defined configASSERT()?

    http://www.FreeRTOS.org/support - In return for receiving this top quality
    embedded software for free we request you assist our global community by
    participating in the support forum.

    http://www.FreeRTOS.org/training - Investing in training allows your team to
    be as productive as possible as early as possible.  Now you can receive
    FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
    Ltd, and the world's leading authority on the world's leading RTOS.

    http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
    including FreeRTOS+Trace - an indispensable productivity tool, a DOS
    compatible FAT file system, and our tiny thread aware UDP/IP stack.

    http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
    Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.

    http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
    Integrity Systems ltd. to sell under the OpenRTOS brand.  Low cost OpenRTOS
    licenses offer ticketed support, indemnification and commercial middleware.

    http://www.SafeRTOS.com - High Integrity Systems also provide a safety
    engineered and independently SIL3 certified version for use in safety and
    mission critical applications that require provable dependability.

    1 tab == 4 spaces!
*/

#pragma comment( lib, "ws2_32.lib" )

/* Win32 includes. */
#include <WinSock2.h>
#include <stdio.h>

/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"

/* FreeRTOS+CLI includes. */
#include "FreeRTOS_CLI.h"

/* Dimensions the buffer into which input characters are placed. */
#define cmdMAX_INPUT_SIZE	60

/* Dimensions the buffer into which string outputs can be placed. */
#define cmdMAX_OUTPUT_SIZE	1024

/* Dimensions the buffer passed to the recvfrom() call. */
#define cmdSOCKET_INPUT_BUFFER_SIZE 60

/*
 * Open and configure the UDP socket.
 */
static SOCKET prvOpenUDPSocket( void );

/*-----------------------------------------------------------*/

/*
 * Task that provides the input and output for the FreeRTOS+CLI command
 * interpreter.  In this case a UDP port is used.  See the URL in the comments
 * within main.c for the location of the online documentation.
 */
void vUDPCommandInterpreterTask( void *pvParameters )
{
long lBytes, lByte;
signed char cInChar, cInputIndex = 0;
static signed char cInputString[ cmdMAX_INPUT_SIZE ], cOutputString[ cmdMAX_OUTPUT_SIZE ], cLocalBuffer[ cmdSOCKET_INPUT_BUFFER_SIZE ];
BaseType_t xMoreDataToFollow;
volatile int iErrorCode = 0;
struct sockaddr_in xClient;
int xClientAddressLength = sizeof( struct sockaddr_in );
SOCKET xSocket;

	/* Just to prevent compiler warnings. */
	( void ) pvParameters;

	/* Attempt to open the socket. */
	xSocket = prvOpenUDPSocket();

	if( xSocket != INVALID_SOCKET )
	{
		for( ;; )
		{
			/* Wait for incoming data on the opened socket. */
			lBytes = recvfrom( xSocket, cLocalBuffer, sizeof( cLocalBuffer ), 0, ( struct sockaddr * ) &xClient, &xClientAddressLength );

			if( lBytes == SOCKET_ERROR )
			{
				/* Something went wrong, but it is not handled by this simple
				example. */
				iErrorCode = WSAGetLastError();
			}
			else
			{
				/* Process each received byte in turn. */
				lByte = 0;
				while( lByte < lBytes )
				{
					/* The next character in the input buffer. */
					cInChar = cLocalBuffer[ lByte ];
					lByte++;

					/* Newline characters are taken as the end of the command
					string. */
					if( cInChar == '\n' )
					{
						/* Process the input string received prior to the
						newline. */
						do
						{
							/* Pass the string to FreeRTOS+CLI. */
							xMoreDataToFollow = FreeRTOS_CLIProcessCommand( cInputString, cOutputString, cmdMAX_OUTPUT_SIZE );

							/* Send the output generated by the command's
							implementation. */
							sendto( xSocket, cOutputString,  strlen( cOutputString ), 0, ( SOCKADDR * ) &xClient, xClientAddressLength );

						} while( xMoreDataToFollow != pdFALSE ); /* Until the command does not generate any more output. */

						/* All the strings generated by the command processing
						have been sent.  Clear the input string ready to receive
						the next command. */
						cInputIndex = 0;
						memset( cInputString, 0x00, cmdMAX_INPUT_SIZE );

						/* Transmit a spacer, just to make the command console
						easier to read. */
						sendto( xSocket, "\r\n",  strlen( "\r\n" ), 0, ( SOCKADDR * ) &xClient, xClientAddressLength );
					}
					else
					{
						if( cInChar == '\r' )
						{
							/* Ignore the character.  Newlines are used to
							detect the end of the input string. */
						}
						else if( cInChar == '\b' )
						{
							/* Backspace was pressed.  Erase the last character
							in the string - if any. */
							if( cInputIndex > 0 )
							{
								cInputIndex--;
								cInputString[ cInputIndex ] = '\0';
							}
						}
						else
						{
							/* A character was entered.  Add it to the string
							entered so far.  When a \n is entered the complete
							string will be passed to the command interpreter. */
							if( cInputIndex < cmdMAX_INPUT_SIZE )
							{
								cInputString[ cInputIndex ] = cInChar;
								cInputIndex++;
							}
						}
					}
				}
			}
		}
	}
	else
	{
		/* The socket could not be opened. */
		vTaskDelete( NULL );
	}
}
/*-----------------------------------------------------------*/

static SOCKET prvOpenUDPSocket( void )
{
WSADATA xWSAData;
WORD wVersionRequested;
struct sockaddr_in xServer;
SOCKET xSocket = INVALID_SOCKET;

	wVersionRequested = MAKEWORD( 2, 2 );

	/* Prepare to use WinSock. */
	if( WSAStartup( wVersionRequested, &xWSAData ) != 0 )
	{
		fprintf( stderr, "Could not open Windows connection.\n" );
	}
	else
	{
		xSocket = socket( AF_INET, SOCK_DGRAM, 0 );
		if( xSocket == INVALID_SOCKET)
		{
			fprintf( stderr, "Could not create socket.\n" );
			WSACleanup();
		}
		else
		{
			/* Zero out the server structure. */
			memset( ( void * ) &xServer, 0x00, sizeof( struct sockaddr_in ) );

			/* Set family and port. */
			xServer.sin_family = AF_INET;
			xServer.sin_port = htons( configUDP_CLI_PORT_NUMBER );

			/* Assign the loopback address */
			xServer.sin_addr.S_un.S_un_b.s_b1 = 127;
			xServer.sin_addr.S_un.S_un_b.s_b2 = 0;
			xServer.sin_addr.S_un.S_un_b.s_b3 = 0;
			xServer.sin_addr.S_un.S_un_b.s_b4 = 1;

			/* Bind the address to the socket. */
			if( bind( xSocket, ( struct sockaddr * ) &xServer, sizeof( struct sockaddr_in ) ) == -1 )
			{
				fprintf( stderr, "Could not socket to port %d.\n", configUDP_CLI_PORT_NUMBER );
				closesocket( xSocket );
				xSocket = INVALID_SOCKET;
				WSACleanup();
			}
		}
	}

	return xSocket;
}