/*
 * tcp_timer.c
 *
 *  Created on: 21.01.2012
 *      Author: Oliver
 */

#include <thread.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include "tcp_timer.h"
#include "vtimer.h"
#include "thread.h"
#include "destiny.h"
#include "socket.h"
#include "net_help/msg_help.h"
#include "sys/net/sixlowpan/sixlowpan.h"

void handle_synchro_timeout(socket_internal_t *current_socket)
	{
	msg_t send;
	if (thread_getstatus(current_socket->recv_pid) == STATUS_RECEIVE_BLOCKED)
		{
		if ((current_socket->socket_values.tcp_control.no_of_retries == 0) &&
				(timex_sub(vtimer_now(), current_socket->socket_values.tcp_control.last_packet_time).microseconds >
				TCP_SYN_INITIAL_TIMEOUT))
			{
			current_socket->socket_values.tcp_control.no_of_retries++;
			net_msg_send(&send, current_socket->recv_pid, 0, TCP_RETRY);
//			printf("FIRST RETRY!\n");
			}
		else if ((current_socket->socket_values.tcp_control.no_of_retries > 0) &&
				(timex_sub(vtimer_now(), current_socket->socket_values.tcp_control.last_packet_time).microseconds >
				(current_socket->socket_values.tcp_control.no_of_retries * TCP_SYN_TIMEOUT + TCP_SYN_INITIAL_TIMEOUT)))
			{
			current_socket->socket_values.tcp_control.no_of_retries++;
			if (current_socket->socket_values.tcp_control.no_of_retries > TCP_MAX_SYN_RETRIES)
				{
				net_msg_send(&send, current_socket->recv_pid, 0, TCP_TIMEOUT);
//				printf("TCP SYN TIMEOUT!!\n");
				}
			else
				{
				net_msg_send(&send, current_socket->recv_pid, 0, TCP_RETRY);
//				printf("NEXT RETRY!\n");
				}
			}
		}
	}

void handle_established(socket_internal_t *current_socket)
	{
	msg_t send;
	double current_timeout = current_socket->socket_values.tcp_control.rto;
	if (current_timeout < SECOND)
		{
		current_timeout = SECOND;
		}
	uint8_t i;
	if ((current_socket->socket_values.tcp_control.send_nxt > current_socket->socket_values.tcp_control.send_una) &&
			(thread_getstatus(current_socket->send_pid) == STATUS_RECEIVE_BLOCKED))
		{
		for(i = 0; i < current_socket->socket_values.tcp_control.no_of_retries; i++)
			{
			current_timeout *= 2;
			}
		if (current_timeout > TCP_ACK_MAX_TIMEOUT)
			{
			net_msg_send(&send, current_socket->send_pid, 0, TCP_TIMEOUT);
//			printf("GOT NO ACK: TIMEOUT!\n");
			}
		else if (timex_sub(vtimer_now(), current_socket->socket_values.tcp_control.last_packet_time).microseconds >
					current_timeout)
			{
//			printReasBuffers();
			current_socket->socket_values.tcp_control.no_of_retries++;
			net_msg_send(&send, current_socket->send_pid, 0, TCP_RETRY);
//			printf("GOT NO ACK YET, %i. RETRY! Now: %lu  Before: %lu, Diff: %lu, Cur Timeout: %f\n", current_socket->socket_values.tcp_control.no_of_retries,
//					vtimer_now().microseconds, current_socket->socket_values.tcp_control.last_packet_time.microseconds,
//					vtimer_now().microseconds - current_socket->socket_values.tcp_control.last_packet_time.microseconds,
//					current_timeout);
			}
		}
	}

void check_sockets(void)
	{
	socket_internal_t *current_socket;
	uint8_t i = 1;
	while (i < MAX_SOCKETS+1)
		{
		current_socket = getSocket(i);

		if(isTCPSocket(i))
			{
			switch (current_socket->socket_values.tcp_control.state)
				{
				case ESTABLISHED:
					{
					handle_established(current_socket);
					break;
					}
				case SYN_SENT:
					{
					handle_synchro_timeout(current_socket);
					break;
					}
				case SYN_RCVD:
					{
					handle_synchro_timeout(current_socket);
					break;
					}
				default:
					{
					break;
					}
				}
			}
		i++;
		}
	}

void inc_global_variables(void)
	{
	mutex_lock(&global_sequence_clunter_mutex);
	global_sequence_counter += rand();
	mutex_unlock(&global_sequence_clunter_mutex, 0);
#ifdef TCP_HC
	mutex_lock(&global_context_counter_mutex);
	global_context_counter += rand();
	mutex_unlock(&global_context_counter_mutex, 0);
#endif
	}

void tcp_general_timer(void)
	{
	vtimer_t tcp_vtimer;
	timex_t interval = timex_set(0, TCP_TIMER_RESOLUTION);

	while (1)
		{
		inc_global_variables();
		check_sockets();
		vtimer_set_wakeup(&tcp_vtimer, interval, thread_getpid());
		thread_sleep();
		}
	}