<?php
/**
* @brief Contains the controler of the Resources Object (create, save, modify, etc...)
*/

// To activate de debug mode of the class
$_ENV['DEBUG'] = false;

// Loads the required class
try {
	require_once("class/class_db.php");
	require_once("class/Resources.php");
} catch (Exception $e){
	echo $e->getMessage().' // ';
}


/**
* @brief  Controler of the Resources Object 
*
*<ul>
*  <li>Get an Resources object from an id</li>
*  <li>Save in the database a resource</li>
*  <li>Manage the operation on the resources related tables in the database (insert, select, update, delete)</li>
*</ul>
*/
class ResourcesControler
{
	/**
	* Dbquery object used to connnect to the database
    */
	static $db;
	
	/**
	* Resources table
    */
	static $resources_table;
	
	/**
	* Opens a database connexion and values the tables variables
	*/
	public function connect()
	{
		$db = new dbquery();
		$db->connect();
		
		self::$resources_table = $_SESSION['ressources'][0]['tablename'];
		self::$db=$db;
	}	
	
	/**
	* Close the database connexion
	*/
	public function disconnect()
	{
		self::$db->disconnect();
	}	
	
	/**
	* Returns an Resources Object based on a resources identifier
	*
	* @param  $res_id bigint  Resources identifier
	* @return Resources object with properties from the database or null
	*/
	public function get($res_id)
	{	
		// If no res_id specified return null
		if(empty($res_id))
			return null;
		
		self::connect();
		$query = "select * from ".self::$resources_table." where res_id = '".$res_id."' ";
		
		if(!$can_be_disabled)
			$query .= " and enabled = 'Y'";

		try{
			if($_ENV['DEBUG'])
				echo $query.' // ';
			self::$db->query($query);
		} catch (Exception $e){
			echo _NO_RESOURCE_WITH_ID.' '.$res_id.' // ';
		}
		
		if(self::$db->nb_result() > 0)
		{
			$resources=new Resources();
			$queryResult=self::$db->fetch_object();
			foreach($queryResult as $key => $value){
				$resources->$key=$value;
			}
			self::disconnect();
			return $resources;
		}
		else
		{
			self::disconnect();
			return null;
		}
	}
	
	/**
	* Saves in the database a Resources object 
	*
	* @param  $resources Resources object to be saved
	* @param  $mode string  Saving mode : add or up
	* @return bool true if the save is complete, false otherwise
	*/
	public function save($resources, $mode)
	{
		if(!isset($resources))
			return false;
			
		if($mode == "up")
			return self::update($resources);
		elseif($mode =="add") 
			return self::insert($resources);
		
		return false;
	}
	
	/**
	* Inserts in the database (Resources table) a Resources object
	*
	* @param  $resources Resources object
	* @return bool true if the insertion is complete, false otherwise
	*/
	private function insert($resources)
	{
		if(!isset($resources))
			return false;
			
		self::connect();
		$prep_query = self::insert_prepare($resources);
		
		// Inserting object
		$query="insert into ".self::$resources_table." ("
					.$prep_query['COLUMNS']
					.") values("
					.$prep_query['VALUES']
					.")";
		try{
			if($_ENV['DEBUG']){ echo $query.' // '; }
			self::$db->query($query);
			$ok = true;
		} catch (Exception $e){
			echo _CANNOT_INSERT_RESOURCES." ".$resources->toString().' // ';
			$ok = false;
		}
		self::disconnect();
		return $ok;
	}

	/**
	* Updates a Resources in the database (Resources table) with a Resources object
	*
	* @param  $resources Resources object
	* @return bool true if the update is complete, false otherwise
	*/
	private function update($resources)
	{
		if(!isset($resources) )
			return false;

		self::connect();
		$query="update ".self::$resources_table." set "
					.self::update_prepare($resources)
					." where res_id='".$resources->res_id."'"; 
					
		try{
			if($_ENV['DEBUG']){echo $query.' // ';}
			self::$db->query($query);
			$ok = true;
		} catch (Exception $e){
			echo _CANNOT_UPDATE_RESOURCES." ".$resources->toString().' // ';
			$ok = false;
		}
		self::disconnect();
		return $ok;
	}
	
	/**
	* Prepares the update query for a given Resources object
	*
	* @param  $resources Resources object
	* @return String containing the fields and the values 
	*/
	private function update_prepare($resources)
	{	
		$result=array();
		foreach($resources->getArray() as $key => $value)
		{
			// For now all fields in the Resources table are strings
			if(!empty($value))
			{
				$result[]=$key."='".$value."'";
			}
		}

		return implode(",",$result);
	} 
	
	/**
	* Prepares the insert query for a given Resources object
	*
	* @param  $resources Resources object
	* @return Array containing the fields and the values 
	*/
	private function insert_prepare($resources)
	{
		$columns=array();
		$values=array();
		foreach($resources->getArray() as $key => $value)
		{
			// For now all fields in the Resources table are strings
			if(!empty($value))
			{
				$columns[]=$key;
				$values[]="'".$value."'";
			}
		}
		return array('COLUMNS' => implode(",",$columns), 'VALUES' => implode(",",$values));
	}
	
	/**
	* Asserts if a given Resources (res_id) exists in the database
	* 
	* @param  $res_id String Resources identifier
	* @return bool true if the Resources exists, false otherwise 
	*/
	public function resExists($res_id)
	{
		if(!isset($res_id) || empty($res_id))
			return false;

		self::connect();
		$query = "select res_id from ".self::$resources_table." where res_id = '".$res_id."'";
		try{
			if($_ENV['DEBUG']){echo $query.' // ';}
			self::$db->query($query);
		} catch (Exception $e){
			echo _UNKNOWN._RESOURCES." ".$res_id.' // ';
		}
		
		if(self::$db->nb_result() > 0)
		{
			self::disconnect();
			return true;
		}
		self::disconnect();
		return false;
	}
	
	/**
	* Convert an object to an array
	* @param  $object object to convert
	*/
	public function object2array($object)
	{
		$return = NULL;
		if(is_array($object))
		{
			foreach($object as $key => $value)
			{
				$return[$key] = $this->object2array($value);
			}
		}
		else
		{
			if(is_object($object))
			{
				$var = get_object_vars($object);
				if($var)
				{
					foreach($var as $key => $value)
					{
						$return[$key] = ($key && !$value) ? NULL : $this->object2array($value);
					}
				}
				else return $object;
			}
			else return $object;
		}
		return $return;
	}
	
	/**
	* Load into session vars all the config of resources
	*/
	public function loadResourcesConfig($path)
	{
		return $this->object2array(simplexml_load_file($path));
	}
}
?>