/*
 * tcp.h
 *
 *  Created on: 29.09.2011
 *      Author: Oliver
 */

#ifndef TCP_H_
#define TCP_H_

#define TCP_HC

#define TCP_HDR_LEN 			20

enum tcp_flags
	{
	TCP_ACK			= 0x08,
	TCP_URG_PSH		= 0x14,
	TCP_RST			= 0x20,
	TCP_SYN			= 0x40,
	TCP_SYN_ACK		= 0x48,
	TCP_FIN			= 0x80,
	TCP_FIN_ACK		= 0x88
	};

enum tcp_states
	{
	CLOSED      	= 0,
	LISTEN      	= 1,
	SYN_SENT    	= 2,
	SYN_RCVD    	= 3,
	ESTABLISHED 	= 4,
	FIN_WAIT_1  	= 5,
	FIN_WAIT_2  	= 6,
	CLOSE_WAIT  	= 7,
	CLOSING     	= 8,
	LAST_ACK    	= 9,
	TIME_WAIT   	= 10,
	UNKNOWN			= 11
	};

enum tcp_codes
	{
	UNDEFINED			= 0,
	PACKET_OK			= 1,
	CLOSE_CONN			= 2,
	SEQ_NO_TOO_SMALL	= 3,
	ACK_NO_TOO_SMALL 	= 4,
	ACK_NO_TOO_BIG		= 5
	};

#define REMOVE_RESERVED 		0xFC

#define IS_TCP_ACK(a) 			((a & TCP_ACK) 		> 0)	// Test for ACK flag only, ignore URG und PSH flag
#define IS_TCP_RST(a) 			((a & TCP_RST) 		> 0)
#define IS_TCP_SYN(a) 			((a & TCP_SYN) 		> 0)
#define IS_TCP_SYN_ACK(a) 		((a & TCP_SYN_ACK) 	> 0)
#define IS_TCP_FIN(a) 			((a & TCP_FIN) 		> 0)
#define IS_TCP_FIN_ACK(a) 		((a & TCP_FIN_ACK) 	> 0)

#define SET_TCP_ACK(a)			a = ((a & 0x00) | TCP_ACK)
#define SET_TCP_RST(a) 			a = ((a & 0x00) | TCP_RST)
#define SET_TCP_SYN(a) 			a = ((a & 0x00) | TCP_SYN)
#define SET_TCP_SYN_ACK(a) 		a = ((a & 0x00) | TCP_SYN_ACK)
#define SET_TCP_FIN(a) 			a = ((a & 0x00) | TCP_FIN)
#define SET_TCP_FIN_ACK(a) 		a = ((a & 0x00) | TCP_FIN_ACK)

// TODO: Probably stack size too high
#define TCP_STACK_SIZE 			3072

#include "sys/net/sixlowpan/sixlowip.h"

typedef struct __attribute__ ((packed)) tcp_h_t
	{
    uint16_t 	src_port;
    uint16_t 	dst_port;
    uint32_t 	seq_nr;
    uint32_t 	ack_nr;
    uint8_t 	dataOffset_reserved;
    uint8_t 	reserved_flags;
    uint16_t 	window;
    uint16_t	checksum;
    uint16_t	urg_pointer;
	} tcp_hdr_t;


// uint8_t buffer_tcp[BUFFER_SIZE];
char tcp_stack_buffer[TCP_STACK_SIZE];

#ifdef TCP_HC
mutex_t				global_context_counter_mutex;
uint8_t				global_context_counter;
#endif

mutex_t				global_sequence_clunter_mutex;
uint32_t			global_sequence_counter;

void tcp_packet_handler (void);
uint16_t tcp_csum(ipv6_hdr_t *ipv6_header, tcp_hdr_t *tcp_header);
void printTCPHeader(tcp_hdr_t *tcp_header);
void printArrayRange_tcp(uint8_t *udp_header, uint16_t len);

#endif /* TCP_H_ */