/*
 * FreeRTOS Kernel V10.1.0
 * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * http://www.FreeRTOS.org
 * http://aws.amazon.com/freertos
 *
 * 1 tab == 4 spaces!
 */

/* Standard includes. */
#include "stdlib.h"

/* lwIP core includes */
#include "lwip/opt.h"
#include "lwip/sockets.h"

/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"

/* Utils includes. */
#include "CommandInterpreter.h"

/* Dimensions the buffer into which input characters are placed. */
#define cmdMAX_INPUT_SIZE	20

/* Dimensions the buffer into which string outputs can be placed. */
#define cmdMAX_OUTPUT_SIZE	1024

/*-----------------------------------------------------------*/

void vBasicSocketsCommandInterpreterTask( void *pvParameters )
{
long lSocket, lClientFd, lBytes, lAddrLen = sizeof( struct sockaddr_in );
struct sockaddr_in sLocalAddr;
struct sockaddr_in client_addr;
const signed char *pcWelcomeMessage = "FreeRTOS command server - connection accepted.\r\nType Help to view a list of registered commands.\r\n\r\n>";
signed char cInChar, cInputIndex;
static signed char cInputString[ cmdMAX_INPUT_SIZE ], cOutputString[ cmdMAX_OUTPUT_SIZE ];
portBASE_TYPE xReturned;

	( void ) pvParameters;

	lSocket = lwip_socket(AF_INET, SOCK_STREAM, 0);

	if( lSocket >= 0 )
	{
		memset((char *)&sLocalAddr, 0, sizeof(sLocalAddr));
		sLocalAddr.sin_family = AF_INET;
		sLocalAddr.sin_len = sizeof(sLocalAddr);
		sLocalAddr.sin_addr.s_addr = htonl(INADDR_ANY);
		sLocalAddr.sin_port = ntohs( ( ( unsigned short ) 23 ) );

		if( lwip_bind( lSocket, ( struct sockaddr *) &sLocalAddr, sizeof( sLocalAddr ) ) < 0 ) 
		{
			lwip_close( lSocket );
			vTaskDelete( NULL );
		}

		if( lwip_listen( lSocket, 20 ) != 0 )
		{
			lwip_close( lSocket );
			vTaskDelete( NULL );
		}

		for( ;; )
		{

			lClientFd = lwip_accept(lSocket, ( struct sockaddr * ) &client_addr, ( u32_t * ) &lAddrLen );

			if( lClientFd > 0L )
			{
				lwip_send( lClientFd, pcWelcomeMessage, strlen( ( const char * ) pcWelcomeMessage ), 0 );

				cInputIndex = 0;
				memset( cInputString, 0x00, cmdMAX_INPUT_SIZE );

				do
				{					
					lBytes = lwip_recv( lClientFd, &cInChar, sizeof( cInChar ), 0 );

					if( lBytes > 0L ) 
					{
						if( cInChar == '\n' )
						{
							/* The input string has been terminated.  Was the 
							input a quit command? */
							if( strcmp( "quit", ( const char * ) cInputString ) == 0 )
							{
								/* Set lBytes to 0 to close the connection. */
								lBytes = 0L;
							}
							else
							{
								/* The input string was not a quit command.  
								Pass the string to the command interpreter. */
								do
								{
									xReturned = xCmdIntProcessCommand( cInputString, cOutputString, cmdMAX_OUTPUT_SIZE );
									lwip_send( lClientFd, cOutputString, strlen( ( const char * ) cOutputString ), 0 );

								} while( xReturned != pdFALSE );

								/* All the strings generated by the input 
								command have been sent.  Clear the input
								string ready to receive the next command. */
								cInputIndex = 0;
								memset( cInputString, 0x00, cmdMAX_INPUT_SIZE );
								lwip_send( lClientFd, "\r\n>", strlen( "\r\n>" ), 0 );
							}
						}
						else
						{
							if( cInChar == '\r' )
							{
								/* Ignore the character. */
							}
							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++;
								}
							}
						}
					}

				} while( lBytes > 0L );

				 lwip_close( lClientFd );
			}
		} 
	}

	/* Will only get here if a listening socket could not be created. */
	vTaskDelete( NULL );
}