<?php
/*
#  Copyright (c) 2012, Gjøvik University College
#  All rights reserved.

#  Redistribution and use 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 Gjøvik University College nor the
#        names of its contributors may be used to endorse or promote products
#        derived from this software without specific prior written permission.
#  
#  THIS SOFTWARE IS PROVIDED BY Gjøvik University College ''AS IS'' AND ANY
#  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
#  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
#  DISCLAIMED. IN NO EVENT SHALL Gjøvik University College BE LIABLE FOR ANY
#  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
#  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
#  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
#  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
#  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
#  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
require_once('config.php');
require_once('lib/common_functions.php');
require_once('lib/db_functions.php');


function get_destination ( $alias_username, $alias_domain )
{
	global $config;

	$aliases = array();

	// Terminate early on missing param.
	if (!( $alias_username && $alias_domain)) return $aliases;

	$query = sprintf("SELECT CONCAT(username, '@', domain ) AS destination, CONCAT( alias_username, '@', alias_domain) AS alias FROM %s" 
		. " WHERE alias_username = '%s' AND alias_domain = '%s'",
		$config['kamailio_alias_table'], 
		sql_clean($alias_username), 
		sql_clean($alias_domain)
	);

	$result = sql_dbquery( $config['kamailio_db'], $query);
	// If result is empty, there was either an SQL error, or simply no results.
	// At this point, no error checking is performed, instead the empty array is returned.
	if ( ! $result ) return $aliases; 

	while ( $row = @mysql_fetch_assoc( $result ) )
	{
		array_push( $aliases, array( 'destination' => $row['destination'], 'alias' => $row['alias'] ) );
	}
	return $aliases;
}

function get_aliases ( $dest_username, $dest_domain )
{
	global $config;

	$aliases = array();
	$query = "";
	if (( $dest_username == null ) && ( $dest_domain == null) )
	{
		$query = sprintf("SELECT CONCAT(username, '@', domain ) AS destination, CONCAT( alias_username, '@', alias_domain) AS alias FROM %s" ,
			$config['kamailio_alias_table']);
	}
	else
	{
		$query = sprintf("SELECT '%s' AS destination, CONCAT( alias_username, '@', alias_domain) AS alias FROM %s" 
			. " WHERE username = '%s' AND domain = '%s'",
			sql_clean($dest_username. '@' . $dest_domain),
			$config['kamailio_alias_table'], 
			sql_clean($dest_username), 
			sql_clean($dest_domain));
	}
	$result = sql_dbquery( $config['kamailio_db'], $query);
	// If result is empty, there was either an SQL error, or simply no results.
	// At this point, no error checking is performed, instead the empty array is returned.
	if ( ! $result ) return $aliases; 

	while ( $row = @mysql_fetch_assoc( $result ) )
	{
		array_push( $aliases, array( 'destination' => $row['destination'], 'alias' => $row['alias'] ) );
	}
	return $aliases;
}

function get_e164_alias( $dest_username, $dest_domain )
{
	global $config;
	$cur_aliases = get_aliases( $dest_username, $dest_domain );
	foreach ( $cur_aliases as $testalias )
	{
		list( $tau, $foo ) = split_sipaddress( $testalias['alias'] );
		if ( verify_e164 ( $tau ) ) return $testalias;
	}
	return false;

}
function alias_exists( $alias_username, $alias_domain )
{
	global $config;
	$query = sprintf("SELECT COUNT(*) AS num FROM %s  WHERE alias_username = '%s' AND alias_domain = '%s'",
		$config['kamailio_alias_table'],
		sql_clean($alias_username), sql_clean($alias_domain));
	$result = sql_dbquery($config['kamailio_db'], $query);

	if ( !$result ) return true; // This is an error. Better to fail claiming alias exists...
	$row = @mysql_fetch_row($result);
	if ( !$row ) return true; // This is an error. Better to fail claiming alias exists...
	$num_r = $row[0];
	if ( $num_r == 1 ) 
	{
		$query = sprintf("SELECT CONCAT(username, '@', domain ) AS destination FROM %s  WHERE alias_username = '%s' AND alias_domain = '%s'",
			$config['kamailio_alias_table'],
			sql_clean($alias_username), sql_clean($alias_domain));
		$result = sql_dbquery($config['kamailio_db'], $query);
		$row =  @mysql_fetch_row($result);
		if ( is_string( $row[0] ) ) return $row[0];
		return true; // Failure mode..
	}

	return false;
}

function add_alias( $alias_username, $alias_domain, $dest_username, $dest_domain )
{
	global $config;
	// The following will, in normal cases, lead to a double-test, and double the number of queries...
	// Defensive comment: better safe than sorry :P
	if ( alias_exists( $alias_username, $alias_domain ) )
		return false;

	$query = sprintf("INSERT INTO %s ( alias_username, alias_domain, username, domain) VALUES ('%s','%s','%s','%s')",
		$config['kamailio_alias_table'],
		sql_clean($alias_username), sql_clean($alias_domain),
		sql_clean($dest_username), sql_clean($dest_domain));

	return sql_dbexec( $config['kamailio_db'], $query);
	
}

function remove_alias ( $alias_username, $alias_domain )
{
	global $config;
	if (! alias_exists ( $alias_username, $alias_domain ) ) return false;
	$query = sprintf ("DELETE FROM %s WHERE alias_username = '%s' AND alias_domain = '%s'",	
		$config['kamailio_alias_table'],
		sql_clean( $alias_username ),
		sql_clean( $alias_domain ));
	return sql_dbexec( $config['kamailio_db'], $query);

}

?>