/*********************************************************************************************************
* Software License Agreement (BSD License)                                                               *
* Author: Sebastien Decugis <sdecugis@nict.go.jp>							 *
*													 *
* Copyright (c) 2009, WIDE Project and NICT								 *
* All rights reserved.											 *
* 													 *
* Redistribution and use of this software in source and binary forms, with or without modification, are  *
* permitted provided that the following conditions are met:						 *
* 													 *
* * Redistributions of source code must retain the above 						 *
*   copyright notice, this list of conditions and the 							 *
*   following disclaimer.										 *
*    													 *
* * Redistributions in binary form must reproduce the above 						 *
*   copyright notice, this list of conditions and the 							 *
*   following disclaimer in the documentation and/or other						 *
*   materials provided with the distribution.								 *
* 													 *
* * Neither the name of the WIDE Project or NICT nor the 						 *
*   names of its contributors may be used to endorse or 						 *
*   promote products derived from this software without 						 *
*   specific prior written permission of WIDE Project and 						 *
*   NICT.												 *
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
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*********************************************************************************************************/

#include "fD.h"

const char *peer_state_str[] = { 
	  "STATE_ZOMBIE"
	, "STATE_OPEN"
	, "STATE_CLOSED"
	, "STATE_CLOSING"
	, "STATE_WAITCNXACK"
	, "STATE_WAITCNXACK_ELEC"
	, "STATE_WAITCEA"
	, "STATE_SUSPECT"
	, "STATE_REOPEN"
	};

const char * fd_pev_str(int event)
{
	switch (event) {
	#define case_str( _val )\
		case _val : return #_val
		case_str(FDEVP_TERMINATE);
		case_str(FDEVP_DUMP_ALL);
		case_str(FDEVP_MSG_INCOMING);
		case_str(FDEVP_PSM_TIMEOUT);
		
		default:
			TRACE_DEBUG(FULL, "Unknown event : %d", event);
			return "Unknown event";
	}
}


static int started = 0;
static pthread_mutex_t  started_mtx = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t   started_cnd = PTHREAD_COND_INITIALIZER;

/* Wait for start signal */
static int fd_psm_waitstart()
{
	TRACE_ENTRY("");
	CHECK_POSIX( pthread_mutex_lock(&started_mtx) );
awake:	
	if (! started) {
		pthread_cleanup_push( fd_cleanup_mutex, &started_mtx );
		CHECK_POSIX( pthread_cond_wait(&started_cnd, &started_mtx) );
		pthread_cleanup_pop( 0 );
		goto awake;
	}
	CHECK_POSIX( pthread_mutex_unlock(&started_mtx) );
	return 0;
}

/* Cancelation cleanup : set ZOMBIE state in the peer */
void cleanup_state(void * arg) 
{
	struct fd_peer * peer = (struct fd_peer *)arg;
	CHECK_PARAMS_DO( CHECK_PEER(peer), return );
	peer->p_hdr.info.pi_state = STATE_ZOMBIE;
	return;
}

/* Set timeout timer of next event */
static void psm_next_timeout(struct fd_peer * peer, int add_random, int delay)
{
	/* Initialize the timer */
	CHECK_POSIX_DO(  clock_gettime( CLOCK_REALTIME,  &peer->p_psm_timer ), ASSERT(0) );
	
	if (add_random) {
		if (delay > 2)
			delay -= 2;
		else
			delay = 0;

		/* Add a random value between 0 and 4sec */
		peer->p_psm_timer.tv_sec += random() % 4;
		peer->p_psm_timer.tv_nsec+= random() % 1000000000L;
		if (peer->p_psm_timer.tv_nsec > 1000000000L) {
			peer->p_psm_timer.tv_nsec -= 1000000000L;
			peer->p_psm_timer.tv_sec ++;
		}
	}
	
	peer->p_psm_timer.tv_sec += delay;
	
#if 0
	/* temporary for debug */
	peer->p_psm_timer.tv_sec += 10;
#endif
}

static int psm_ev_timedget(struct fd_peer * peer, int *code, void ** data)
{
	struct fd_event * ev;
	int ret = 0;
	
	TRACE_ENTRY("%p %p %p", peer, code, data);
	
	ret = fd_fifo_timedget(peer->p_events, &ev, &peer->p_psm_timer);
	if (ret == ETIMEDOUT) {
		*code = FDEVP_PSM_TIMEOUT;
		*data = NULL;
	} else {
		CHECK_FCT( ret );
		*code = ev->code;
		*data = ev->data;
		free(ev);
	}
	
	return 0;
}	

/* The state machine thread */
static void * p_psm_th( void * arg )
{
	struct fd_peer * peer = (struct fd_peer *)arg;
	int created_started = started;
	
	CHECK_PARAMS_DO( CHECK_PEER(peer), ASSERT(0) );
	
	pthread_cleanup_push( cleanup_state, arg );
	
	/* Set the thread name */
	{
		char buf[48];
		sprintf(buf, "PSM/%.*s", sizeof(buf) - 5, peer->p_hdr.info.pi_diamid);
		fd_log_threadname ( buf );
	}
	
	/* Wait that the PSM are authorized to start in the daemon */
	CHECK_FCT_DO( fd_psm_waitstart(), goto end );
	
	/* The state machine starts in CLOSED state */
	peer->p_hdr.info.pi_state = STATE_CLOSED;
	
	/* Initialize the timer */
	if (peer->p_flags.pf_responder) {
		psm_next_timeout(peer, 0, INCNX_TIMEOUT);
	} else {
		psm_next_timeout(peer, created_started ? 0 : 1, 0);
	}
	
psm:
	do {
		int event;
		void * ev_data;
		
		/* Get next event */
		CHECK_FCT_DO( psm_ev_timedget(peer, &event, &ev_data), goto end );
		TRACE_DEBUG(FULL, "'%s'\t<-- '%s'\t(%p)\t'%s'",
				STATE_STR(peer->p_hdr.info.pi_state),
				fd_pev_str(event), ev_data,
				peer->p_hdr.info.pi_diamid);
		
		/* Now, the action depends on the current state and the incoming event */
		
	
	} while (1);	
	
	
end:	
	/* set STATE_ZOMBIE */
	pthread_cleanup_pop(1);
	return NULL;
}	
	
	


/* Create the PSM thread of one peer structure */
int fd_psm_begin(struct fd_peer * peer )
{
	TRACE_ENTRY("%p", peer);
	TODO("");
	return ENOTSUP;
}

/* End the PSM (clean ending) */
int fd_psm_terminate(struct fd_peer * peer )
{
	TRACE_ENTRY("%p", peer);
	CHECK_PARAMS( CHECK_PEER(peer) );
	CHECK_FCT( fd_event_send(peer->p_events, FDEVP_TERMINATE, NULL) );
	return 0;
}

/* End the PSM violently */
void fd_psm_abord(struct fd_peer * peer )
{
	TRACE_ENTRY("%p", peer);
	TODO("Cancel PSM thread");
	TODO("Cancel IN thread");
	TODO("Cancel OUT thread");
	TODO("Cleanup the connection");
	return;
}

/* Allow the state machines to start */
int fd_psm_start()
{
	TRACE_ENTRY("");
	CHECK_POSIX( pthread_mutex_lock(&started_mtx) );
	started = 1;
	CHECK_POSIX( pthread_cond_broadcast(&started_cnd) );
	CHECK_POSIX( pthread_mutex_unlock(&started_mtx) );
	return 0;
}