/* $Id$ */
/* 
 * Copyright (C) 2003-2007 Benny Prijono <benny@prijono.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
 */
#include <pjsip-simple/publish.h>
#include <pjsip/sip_auth.h>
#include <pjsip/sip_endpoint.h>
#include <pjsip/sip_errno.h>
#include <pjsip/sip_event.h>
#include <pjsip/sip_msg.h>
#include <pjsip/sip_transaction.h>
#include <pjsip/sip_uri.h>
#include <pjsip/sip_util.h>
#include <pj/assert.h>
#include <pj/guid.h>
#include <pj/log.h>
#include <pj/os.h>
#include <pj/pool.h>
#include <pj/rand.h>
#include <pj/string.h>
#include <pj/timer.h>


#define REFRESH_TIMER		1
#define DELAY_BEFORE_REFRESH	5
#define THIS_FILE		"publishc.c"


/* Let's define this enum, so that it'll trigger compilation error
 * when somebody define the same enum in sip_msg.h
 */
enum
{
    PJSIP_PUBLISH_METHOD = PJSIP_OTHER_METHOD,
};

const pjsip_method pjsip_publish_method = 
{
    (pjsip_method_e)PJSIP_PUBLISH_METHOD,
    { "PUBLISH", 7 }
};


/**
 * SIP client publication structure.
 */
struct pjsip_publishc
{
    pj_pool_t			*pool;
    pjsip_endpoint		*endpt;
    pj_bool_t			 _delete_flag;
    int				 pending_tsx;

    void			*token;
    pjsip_publishc_cb		*cb;

    pj_str_t			 event;
    pj_str_t			 str_target_uri;
    pjsip_uri			*target_uri;
    pjsip_cid_hdr		*cid_hdr;
    pjsip_cseq_hdr		*cseq_hdr;
    pj_str_t			 from_uri;
    pjsip_from_hdr		*from_hdr;
    pjsip_to_hdr		*to_hdr;
    pj_str_t			 etag;
    pjsip_expires_hdr		*expires_hdr;
    pj_uint32_t			 expires;
    pjsip_route_hdr		 route_set;

    /* Authorization sessions. */
    pjsip_auth_clt_sess		 auth_sess;

    /* Auto refresh publication. */
    pj_bool_t			 auto_refresh;
    pj_time_val			 last_refresh;
    pj_time_val			 next_refresh;
    pj_timer_entry		 timer;
};


/*
 * Initialize client publication module.
 */
PJ_DEF(pj_status_t) pjsip_publishc_init_module(pjsip_endpoint *endpt)
{
    return pjsip_endpt_add_capability( endpt, NULL, PJSIP_H_ALLOW, NULL,
				       1, &pjsip_publish_method.name);
}


PJ_DEF(pj_status_t) pjsip_publishc_create( pjsip_endpoint *endpt, 
					   unsigned options,
					   void *token,
					   pjsip_publishc_cb *cb,	
					   pjsip_publishc **p_pubc)
{
    pj_pool_t *pool;
    pjsip_publishc *pubc;
    pj_status_t status;

    /* Verify arguments. */
    PJ_ASSERT_RETURN(endpt && cb && p_pubc, PJ_EINVAL);
    PJ_ASSERT_RETURN(options == 0, PJ_EINVAL);

    PJ_UNUSED_ARG(options);

    pool = pjsip_endpt_create_pool(endpt, "pubc%p", 1024, 1024);
    PJ_ASSERT_RETURN(pool != NULL, PJ_ENOMEM);

    pubc = PJ_POOL_ZALLOC_T(pool, pjsip_publishc);

    pubc->pool = pool;
    pubc->endpt = endpt;
    pubc->token = token;
    pubc->cb = cb;
    pubc->expires = PJSIP_PUBC_EXPIRATION_NOT_SPECIFIED;

    status = pjsip_auth_clt_init(&pubc->auth_sess, endpt, pubc->pool, 0);
    if (status != PJ_SUCCESS)
	return status;

    pj_list_init(&pubc->route_set);

    /* Done */
    *p_pubc = pubc;
    return PJ_SUCCESS;
}


PJ_DEF(pj_status_t) pjsip_publishc_destroy(pjsip_publishc *pubc)
{
    PJ_ASSERT_RETURN(pubc, PJ_EINVAL);

    if (pubc->pending_tsx) {
	pubc->_delete_flag = 1;
	pubc->cb = NULL;
    } else {
	pjsip_endpt_release_pool(pubc->endpt, pubc->pool);
    }

    return PJ_SUCCESS;
}


PJ_DEF(pj_pool_t*) pjsip_publishc_get_pool(pjsip_publishc *pubc)
{
    return pubc->pool;
}

static void set_expires( pjsip_publishc *pubc, pj_uint32_t expires)
{
    if (expires != pubc->expires) {
	pubc->expires_hdr = pjsip_expires_hdr_create(pubc->pool, expires);
    } else {
	pubc->expires_hdr = NULL;
    }
}


PJ_DEF(pj_status_t) pjsip_publishc_init(pjsip_publishc *pubc,
					const pj_str_t *event,
					const pj_str_t *target_uri,
					const pj_str_t *from_uri,
					const pj_str_t *to_uri,
					pj_uint32_t expires)
{
    pj_str_t tmp;

    PJ_ASSERT_RETURN(pubc && event && target_uri && from_uri && to_uri && 
		     expires, PJ_EINVAL);

    /* Copy event type */
    pj_strdup_with_null(pubc->pool, &pubc->event, event);

    /* Copy server URL. */
    pj_strdup_with_null(pubc->pool, &pubc->str_target_uri, target_uri);

    /* Set server URL. */
    tmp = pubc->str_target_uri;
    pubc->target_uri = pjsip_parse_uri( pubc->pool, tmp.ptr, tmp.slen, 0);
    if (pubc->target_uri == NULL) {
	return PJSIP_EINVALIDURI;
    }

    /* Set "From" header. */
    pj_strdup_with_null(pubc->pool, &pubc->from_uri, from_uri);
    tmp = pubc->from_uri;
    pubc->from_hdr = pjsip_from_hdr_create(pubc->pool);
    pubc->from_hdr->uri = pjsip_parse_uri(pubc->pool, tmp.ptr, tmp.slen, 
					  PJSIP_PARSE_URI_AS_NAMEADDR);
    if (!pubc->from_hdr->uri) {
	return PJSIP_EINVALIDURI;
    }

    /* Set "To" header. */
    pj_strdup_with_null(pubc->pool, &tmp, to_uri);
    pubc->to_hdr = pjsip_to_hdr_create(pubc->pool);
    pubc->to_hdr->uri = pjsip_parse_uri(pubc->pool, tmp.ptr, tmp.slen, 
					PJSIP_PARSE_URI_AS_NAMEADDR);
    if (!pubc->to_hdr->uri) {
	return PJSIP_EINVALIDURI;
    }


    /* Set "Expires" header, if required. */
    set_expires( pubc, expires);

    /* Set "Call-ID" header. */
    pubc->cid_hdr = pjsip_cid_hdr_create(pubc->pool);
    pj_create_unique_string(pubc->pool, &pubc->cid_hdr->id);

    /* Set "CSeq" header. */
    pubc->cseq_hdr = pjsip_cseq_hdr_create(pubc->pool);
    pubc->cseq_hdr->cseq = pj_rand() % 0xFFFF;
    pjsip_method_set( &pubc->cseq_hdr->method, PJSIP_REGISTER_METHOD);

    /* Done. */
    return PJ_SUCCESS;
}

PJ_DEF(pj_status_t) pjsip_publishc_set_credentials( pjsip_publishc *pubc,
						int count,
						const pjsip_cred_info cred[] )
{
    PJ_ASSERT_RETURN(pubc && count && cred, PJ_EINVAL);
    return pjsip_auth_clt_set_credentials(&pubc->auth_sess, count, cred);
}

PJ_DEF(pj_status_t) pjsip_publishc_set_route_set( pjsip_publishc *pubc,
					      const pjsip_route_hdr *route_set)
{
    const pjsip_route_hdr *chdr;

    PJ_ASSERT_RETURN(pubc && route_set, PJ_EINVAL);

    pj_list_init(&pubc->route_set);

    chdr = route_set->next;
    while (chdr != route_set) {
	pj_list_push_back(&pubc->route_set, pjsip_hdr_clone(pubc->pool, chdr));
	chdr = chdr->next;
    }

    return PJ_SUCCESS;
}

static pj_status_t create_request(pjsip_publishc *pubc, 
				  pjsip_tx_data **p_tdata)
{
    const pj_str_t STR_EVENT = { "Event", 5 };
    pj_status_t status;
    pjsip_generic_string_hdr *hdr;
    pjsip_tx_data *tdata;

    PJ_ASSERT_RETURN(pubc && p_tdata, PJ_EINVAL);

    /* Create the request. */
    status = pjsip_endpt_create_request_from_hdr( pubc->endpt, 
						  &pjsip_publish_method,
						  pubc->target_uri,
						  pubc->from_hdr,
						  pubc->to_hdr,
						  NULL,
						  pubc->cid_hdr,
						  pubc->cseq_hdr->cseq,
						  NULL,
						  &tdata);
    if (status != PJ_SUCCESS)
	return status;

    /* Add cached authorization headers. */
    pjsip_auth_clt_init_req( &pubc->auth_sess, tdata );

    /* Add Route headers from route set, ideally after Via header */
    if (!pj_list_empty(&pubc->route_set)) {
	pjsip_hdr *route_pos;
	const pjsip_route_hdr *route;

	route_pos = (pjsip_hdr*)
		    pjsip_msg_find_hdr(tdata->msg, PJSIP_H_VIA, NULL);
	if (!route_pos)
	    route_pos = &tdata->msg->hdr;

	route = pubc->route_set.next;
	while (route != &pubc->route_set) {
	    pjsip_hdr *new_hdr = (pjsip_hdr*)
	    			 pjsip_hdr_shallow_clone(tdata->pool, route);
	    pj_list_insert_after(route_pos, new_hdr);
	    route_pos = new_hdr;
	    route = route->next;
	}
    }

    /* Add Event header */
    hdr = pjsip_generic_string_hdr_create(tdata->pool, &STR_EVENT,
					  &pubc->event);
    if (hdr)
	pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr*)hdr);


    /* Add SIP-If-Match if we have etag */
    if (pubc->etag.slen) {
	const pj_str_t STR_HNAME = { "SIP-If-Match", 12 };

	hdr = pjsip_generic_string_hdr_create(tdata->pool, &STR_HNAME,
					      &pubc->etag);
	if (hdr)
	    pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr*)hdr);
    }


    /* Done. */
    *p_tdata = tdata;
    return PJ_SUCCESS;
}


PJ_DEF(pj_status_t) pjsip_publishc_publish(pjsip_publishc *pubc, 
					   pj_bool_t auto_refresh,
					   pjsip_tx_data **p_tdata)
{
    pj_status_t status;
    pjsip_tx_data *tdata;

    PJ_ASSERT_RETURN(pubc && p_tdata, PJ_EINVAL);

    status = create_request(pubc, &tdata);
    if (status != PJ_SUCCESS)
	return status;

    /* Add Expires header */
    if (pubc->expires_hdr) {
	pjsip_hdr *dup;

	dup = (pjsip_hdr*)
	      pjsip_hdr_shallow_clone(tdata->pool, pubc->expires_hdr);
	if (dup)
	    pjsip_msg_add_hdr(tdata->msg, dup);
    }

    /* Cancel existing timer */
    if (pubc->timer.id != 0) {
	pjsip_endpt_cancel_timer(pubc->endpt, &pubc->timer);
	pubc->timer.id = 0;
    }

    pubc->auto_refresh = auto_refresh;

    /* Done */
    *p_tdata = tdata;
    return PJ_SUCCESS;
}


PJ_DEF(pj_status_t) pjsip_publishc_unpublish(pjsip_publishc *pubc,
					     pjsip_tx_data **p_tdata)
{
    pjsip_tx_data *tdata;
    pjsip_msg *msg;
    pjsip_expires_hdr *expires;
    pj_status_t status;

    PJ_ASSERT_RETURN(pubc && p_tdata, PJ_EINVAL);

    if (pubc->timer.id != 0) {
	pjsip_endpt_cancel_timer(pubc->endpt, &pubc->timer);
	pubc->timer.id = 0;
    }

    status = create_request(pubc, &tdata);
    if (status != PJ_SUCCESS)
	return status;

    msg = tdata->msg;

    /* Add Expires:0 header */
    expires = pjsip_expires_hdr_create(tdata->pool, 0);
    pjsip_msg_add_hdr( msg, (pjsip_hdr*)expires);

    *p_tdata = tdata;
    return PJ_SUCCESS;
}


PJ_DEF(pj_status_t) pjsip_publishc_update_expires( pjsip_publishc *pubc,
					           pj_uint32_t expires )
{
    PJ_ASSERT_RETURN(pubc, PJ_EINVAL);
    set_expires( pubc, expires );
    return PJ_SUCCESS;
}


static void call_callback(pjsip_publishc *pubc, pj_status_t status, 
			  int st_code, const pj_str_t *reason,
			  pjsip_rx_data *rdata, pj_int32_t expiration)
{
    struct pjsip_publishc_cbparam cbparam;


    cbparam.pubc = pubc;
    cbparam.token = pubc->token;
    cbparam.status = status;
    cbparam.code = st_code;
    cbparam.reason = *reason;
    cbparam.rdata = rdata;
    cbparam.expiration = expiration;

    (*pubc->cb)(&cbparam);
}

static void pubc_refresh_timer_cb( pj_timer_heap_t *timer_heap,
				   struct pj_timer_entry *entry)
{
    pjsip_publishc *pubc = (pjsip_publishc*) entry->user_data;
    pjsip_tx_data *tdata;
    pj_status_t status;
    
    PJ_UNUSED_ARG(timer_heap);

    entry->id = 0;
    status = pjsip_publishc_publish(pubc, 1, &tdata);
    if (status == PJ_SUCCESS) {
	status = pjsip_publishc_send(pubc, tdata);
    } 
    
    // Callback should have been called.
    // Calling it here will crash the system since pubc might have been
    // destroyed
    //
    //if (status != PJ_SUCCESS) {
    //	char errmsg[PJ_ERR_MSG_SIZE];
    //	pj_str_t reason = pj_strerror(status, errmsg, sizeof(errmsg));
    //	call_callback(pubc, status, 400, &reason, NULL, -1);
    //}
}

static void tsx_callback(void *token, pjsip_event *event)
{
    pj_status_t status;
    pjsip_publishc *pubc = (pjsip_publishc*) token;
    pjsip_transaction *tsx = event->body.tsx_state.tsx;
    
    /* Decrement pending transaction counter. */
    pj_assert(pubc->pending_tsx > 0);
    --pubc->pending_tsx;

    /* If publication data has been deleted by user then remove publication 
     * data from transaction's callback, and don't call callback.
     */
    if (pubc->_delete_flag) {

	/* Nothing to do */
	;

    } else if (tsx->status_code == PJSIP_SC_PROXY_AUTHENTICATION_REQUIRED ||
	       tsx->status_code == PJSIP_SC_UNAUTHORIZED)
    {
	pjsip_rx_data *rdata = event->body.tsx_state.src.rdata;
	pjsip_tx_data *tdata;

	status = pjsip_auth_clt_reinit_req( &pubc->auth_sess,
					    rdata, 
					    tsx->last_tx,  
					    &tdata);

	if (status == PJ_SUCCESS) {
	    status = pjsip_publishc_send(pubc, tdata);
	} 
	
	// Callback should have been called.
	// Calling it here will crash the system since pubc might have been
	// destroyed
	//
	//if (status != PJ_SUCCESS) {
	//    call_callback(pubc, status, tsx->status_code, 
	//		  &rdata->msg_info.msg->line.status.reason,
	//		  rdata, -1);
	//}

	return;

    } else {
	pjsip_rx_data *rdata;
	pj_int32_t expiration = 0xFFFF;

	if (tsx->status_code/100 == 2) {
	    pjsip_msg *msg;
	    pjsip_expires_hdr *expires;
	    pjsip_generic_string_hdr *etag_hdr;
	    const pj_str_t STR_ETAG = { "SIP-ETag", 8 };

	    rdata = event->body.tsx_state.src.rdata;
	    msg = rdata->msg_info.msg;

	    /* Save ETag value */
	    etag_hdr = (pjsip_generic_string_hdr*)
		       pjsip_msg_find_hdr_by_name(msg, &STR_ETAG, NULL);
	    if (etag_hdr) {
		pj_strdup(pubc->pool, &pubc->etag, &etag_hdr->hvalue);
	    } else {
		pubc->etag.slen = 0;
	    }

	    /* Update expires value */
	    expires = (pjsip_expires_hdr*)
	    	      pjsip_msg_find_hdr(msg, PJSIP_H_EXPIRES, NULL);

	    if (expires)
		expiration = expires->ivalue;
	    
	    if (pubc->auto_refresh && expiration!=0 && expiration!=0xFFFF) {
		pj_time_val delay = { 0, 0};

		delay.sec = expiration - DELAY_BEFORE_REFRESH;
		if (pubc->expires != PJSIP_PUBC_EXPIRATION_NOT_SPECIFIED && 
		    delay.sec > (pj_int32_t)pubc->expires) 
		{
		    delay.sec = pubc->expires;
		}
		if (delay.sec < DELAY_BEFORE_REFRESH) 
		    delay.sec = DELAY_BEFORE_REFRESH;
		pubc->timer.cb = &pubc_refresh_timer_cb;
		pubc->timer.id = REFRESH_TIMER;
		pubc->timer.user_data = pubc;
		pjsip_endpt_schedule_timer( pubc->endpt, &pubc->timer, &delay);
		pj_gettimeofday(&pubc->last_refresh);
		pubc->next_refresh = pubc->last_refresh;
		pubc->next_refresh.sec += delay.sec;
	    }

	} else {
	    rdata = (event->body.tsx_state.type==PJSIP_EVENT_RX_MSG) ? 
			event->body.tsx_state.src.rdata : NULL;
	}


	/* Call callback. */
	if (expiration == 0xFFFF) expiration = -1;

	/* Temporarily increment pending_tsx to prevent callback from
	 * destroying pubc.
	 */
	++pubc->pending_tsx;

	call_callback(pubc, PJ_SUCCESS, tsx->status_code, 
		      (rdata ? &rdata->msg_info.msg->line.status.reason 
			: pjsip_get_status_text(tsx->status_code)),
		      rdata, expiration);

	--pubc->pending_tsx;
    }

    /* Delete the record if user destroy pubc during the callback. */
    if (pubc->_delete_flag && pubc->pending_tsx==0) {
	pjsip_publishc_destroy(pubc);
    }
}


PJ_DEF(pj_status_t) pjsip_publishc_send(pjsip_publishc *pubc, 
					pjsip_tx_data *tdata)
{
    pj_status_t status;
    pjsip_cseq_hdr *cseq_hdr;
    pj_uint32_t cseq;

    /* Make sure we don't have pending transaction. */
    if (pubc->pending_tsx) {
	PJ_LOG(4,(THIS_FILE, "Unable to send request, pubc has another "
			     "transaction pending"));
	pjsip_tx_data_dec_ref( tdata );
	return PJSIP_EBUSY;
    }

    /* Invalidate message buffer. */
    pjsip_tx_data_invalidate_msg(tdata);

    /* Increment CSeq */
    cseq = ++pubc->cseq_hdr->cseq;
    cseq_hdr = (pjsip_cseq_hdr*)
    	       pjsip_msg_find_hdr(tdata->msg, PJSIP_H_CSEQ, NULL);
    cseq_hdr->cseq = cseq;

    /* Increment pending transaction first, since transaction callback
     * may be called even before send_request() returns!
     */
    ++pubc->pending_tsx;
    status = pjsip_endpt_send_request(pubc->endpt, tdata, -1, pubc, 
				      &tsx_callback);
    if (status!=PJ_SUCCESS) {
	// no need to decrement, callback has been called and it should
	// already decremented pending_tsx. Decrementing this here may 
	// cause accessing freed memory location.
	//--pubc->pending_tsx;
	PJ_LOG(4,(THIS_FILE, "Error sending request, status=%d", status));
    }

    return status;
}