<?php
/*
* 2007-2011 PrestaShop 
*
* NOTICE OF LICENSE
*
* This source file is subject to the Open Software License (OSL 3.0)
* that is bundled with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://opensource.org/licenses/osl-3.0.php
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@prestashop.com so we can send you a copy immediately.
*
* DISCLAIMER
*
* Do not edit or add to this file if you wish to upgrade PrestaShop to newer
* versions in the future. If you wish to customize PrestaShop for your
* needs please refer to http://www.prestashop.com for more information.
*
*  @author PrestaShop SA <contact@prestashop.com>
*  @copyright  2007-2011 PrestaShop SA
*  @version  Release: $Revision: 7757 $
*  @license    http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
*  International Registered Trademark & Property of PrestaShop SA
*/

/**
 * @todo : Create typed exception for more finer errors check
 * @author Lucas Cherifi - Nans Pellicari - Anatole Korczak - PrestaShop Team
 */
class WebserviceOutputBuilderCore
{
	/**
	 * 
	 * @var int constant
	 */
	const VIEW_LIST = 1;
	const VIEW_DETAILS = 2;
	
	protected $wsUrl;	
	protected $output;
	public $objectRender;
	protected $wsResource;
	protected $depth = 0;
	protected $schemaToDisplay;
	protected $fieldsToDisplay;
	protected $specificFields = array();
	protected $virtualFields = array();
	
	// Header properties
	protected $headerParams = array(
		'Access-Time'	=> 0,
		'X-Powered-By'	=> 0,
		'PSWS-Version'	=> 0,
		'Content-Type'	=> 0,
	);
	
	/** 
	 * @var string Status header sent at return
	 */
	protected $status;
	
	public function __construct($ws_url)
	{
		$this->status = $_SERVER['SERVER_PROTOCOL'].' 200 OK';
		$this->wsUrl = $ws_url;
	}
	
	/**
	 * Set the render object for set the output format.
	 * Set the Content-type for the http header.
	 * 
	 * @param WebserviceOutputInterface $obj_render
	 * @throw WebserviceException if the object render is not an instance of WebserviceOutputInterface
	 * @return $this
	 */
	public function setObjectRender(WebserviceOutputInterface $obj_render)
	{
		if (!$obj_render instanceof WebserviceOutputInterface)
			throw new WebserviceException('Obj_render param must be an WebserviceOutputInterface object type', array(83, 500));
		
		$this->objectRender = $obj_render;
		$this->objectRender->setWsUrl($this->wsUrl);
		if ($this->objectRender->getContentType())
			$this->setHeaderParams('Content-Type', $this->objectRender->getContentType());
		return $this;
	}
	
	/**
	 * getter
	 * @return WebserviceOutputInterface
	 */
	public function getObjectRender()
	{
		return $this->objectRender;
	} 
	
	/**
	 * Need to have the resource list to get the class name for an entity,
	 * To build 
	 * 
	 * @param array $resources
	 * @return $this
	 */
	public function setWsResources($resources)
	{
		$this->wsResource = $resources;
		return $this;
	}
	
	/**
	 * This method return an array with each http header params for a content.
	 * This check each required params.
	 * 
	 * If this method is overrided don't forget to check required specific params (for xml etc...)
	 * 
	 * @return array
	 */
	public function buildHeader()
	{
		$return = array();
		$return[] = $this->status;
		foreach ($this->headerParams as $key => $param)
		{
			$return[] = trim($key).': '.$param;
		}
		return $return;
	}
	
	/**
	 * @param $key The normalized key expected for an http response
	 * @param $value
	 * @throw WebserviceException if the key or the value are corrupted
	 * 		  (use Validate::isCleanHtml method)
	 * @return $this
	 */
	public function setHeaderParams($key, $value)
	{
		if (!Validate::isCleanHtml($key) OR !Validate::isCleanHtml($value))
			throw new WebserviceException('the key or your value is corrupted.', array(94, 500));
		$this->headerParams[$key] = $value;
		return $this;
	}
	
	/**
	 * @param null|string $key if null get all header params otherwise the params specified by the key
	 * @throw WebserviceException if the key is corrupted (use Validate::isCleanHtml method)
	 * @throw WebserviceException if the asked key does'nt exists.
	 * @return array|string
	 */
	public function getHeaderParams($key = null)
	{
		$return = '';
		
		if (!is_null($key))
		{
			if (!is_null($key) && Validate::isCleanHtml($key))
				throw new WebserviceException('the key you write is a corrupted text.', array(95, 500));
			if (!array_key_exists($key, $this->headerParams))
				throw new WebserviceException(sprintf('The key %s does\'nt exist', $key), array(96, 500));
			$return = $this->headerParams[$key];
		}
		else
			$return = $this->headerParams;
		
		return $return;
	}
	
	/**
	 * Delete all Header parameters previously set.
	 * 
	 * @return $this
	 */
	public function resetHeaderParams()
	{
		$this->headerParams = array();
		return $this;
	}
	
	/**
	 * @return string the normalized status for http request
	 */
	public function getStatus()
	{
		return $this->status;
	}
	/**
	 * Set the return header status
	 *
	 * @param int $num the Http status code
	 * @return void
	 */
	public function setStatus($num)
	{
		switch ($num)
		{
			case 200 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 200 OK';
				break;
			case 201 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 201 Created';
				break;
			case 204 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 204 No Content';
				break;
			case 304 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 304 Not Modified';
				break;
			case 400 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 400 Bad Request';
				break;
			case 401 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 401 Unauthorized';
				break;
			case 403 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 403 Forbidden';
				break;
			case 404 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 404 Not Found';
				break;
			case 405 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 405 Method Not Allowed';
				break;
			case 500 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 500 Internal Server Error';
				break;
			case 501 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 501 Not Implemented';
				break;
			case 503 :
				$this->status = $_SERVER['SERVER_PROTOCOL'].' 503 Service Unavailable';
				break;
		}
	}
	
	/**
	 * Build errors output using an error array
	 * 
	 * @param array $errors
	 * @return string output in the format specified by WebserviceOutputBuilder::objectRender
	 */
	public function getErrors($errors)
	{
		if (!empty($errors))
		{
			if (isset($this->objectRender))
			{
				$str_output = $this->objectRender->renderErrorsHeader();
				foreach ($errors as $error)
				{
					if (is_array($error))
						$str_output .=  $this->objectRender->renderErrors($error[1], $error[0]);
					else
						$str_output .=  $this->objectRender->renderErrors($error);
				}
				$str_output .= $this->objectRender->renderErrorsFooter();
				$str_output = $this->objectRender->overrideContent($str_output);
			}
			else
			{
				$str_output = '<pre>'.print_r($errors, true).'</pre>';
			}
		}
		return $str_output;
	}
	
	/**
	 * Build the resource list in the output format specified by WebserviceOutputBuilder::objectRender
	 * @param $key_permissions
	 * @return string
	 */
	public function getResourcesList($key_permissions)
	{
		if (is_null($this->wsResource))
			throw new WebserviceException ('You must set web service resource for get the resources list.', array(82, 500));
		$output = '';
		$more_attr = array('shop_name' => Configuration::get('PS_SHOP_NAME'));
		$output .= $this->objectRender->renderNodeHeader('api', array(), $more_attr);
		foreach ($this->wsResource as $resourceName => $resource)
		{
			if (in_array($resourceName, array_keys($key_permissions)))
			{
				$more_attr = array(
					'xlink_resource'	=> $this->wsUrl.$resourceName,
					'get'				=> (in_array('GET', $key_permissions[$resourceName]) ? 'true' : 'false'),
					'put'				=> (in_array('PUT', $key_permissions[$resourceName]) ? 'true' : 'false'),
					'post'				=> (in_array('POST', $key_permissions[$resourceName]) ? 'true' : 'false'),
					'delete'			=> (in_array('DELETE', $key_permissions[$resourceName]) ? 'true' : 'false'),
					'head'				=> (in_array('HEAD', $key_permissions[$resourceName]) ? 'true' : 'false'),
				);
				$output .= $this->objectRender->renderNodeHeader($resourceName, array(), $more_attr);
				
				$output .= $this->objectRender->renderNodeHeader('description', array(), $more_attr);
				$output .= $resource['description'];
				$output .= $this->objectRender->renderNodeFooter('description', array());
				
				if (!isset($resource['specific_management']) || !$resource['specific_management'])
				{
					$more_attr_schema = array(
						'xlink_resource'	=> $this->wsUrl.$resourceName.'?schema=blank',
						'type'				=> 'blank',
					);
					$output .= $this->objectRender->renderNodeHeader('schema', array(), $more_attr_schema, false);
					$more_attr_schema = array(
						'xlink_resource'	=> $this->wsUrl.$resourceName.'?schema=synopsis',
						'type'				=> 'synopsis',
					);
					$output .= $this->objectRender->renderNodeHeader('schema', array(), $more_attr_schema, false);
				}
				$output .= $this->objectRender->renderNodeFooter($resourceName, array());
			}
		}
		$output .= $this->objectRender->renderNodeFooter('api', array());
		$output = $this->objectRender->overrideContent($output);
		return $output;
	}

	/**
	 * Method is used for each content type
	 * Different content types are :
	 * 		- list of entities,
	 * 		- tree diagram of entity details (full or minimum),
	 * 		- schema (synopsis & blank),
	 * 
	 * @param array $objects each object created by entity asked 
	 * 		  @see WebserviceOutputBuilder::executeEntityGetAndHead
	 * @param null|string $schema_to_display if null display the entities list or entity details.
	 * @param string|array $fields_to_display the fields allow for the output
	 * @param int $depth depth for the tree diagram output.
	 * @param int $type_of_view use the 2 constants WebserviceOutputBuilder::VIEW_LIST WebserviceOutputBuilder::VIEW_DETAILS
	 * @return string in the output format specified by WebserviceOutputBuilder::objectRender
	 */
	public function getContent($objects, $schema_to_display = null, $fields_to_display = 'minimum', $depth = 0, $type_of_view = self::VIEW_LIST, $override = true)
	{
		$this->fieldsToDisplay = $fields_to_display;
		$this->depth = $depth;
		$output = '';
		
		if ($schema_to_display != null)
		{
			$this->schemaToDisplay = $schema_to_display;
			$this->objectRender->setSchemaToDisplay($this->schemaToDisplay);
			
			// If a shema is asked the view must be an details type 
			$type_of_view = self::VIEW_DETAILS;
		}
		
		$ws_params = $objects['empty']->getWebserviceParameters();
		
		// If a list is asked, need to wrap with a plural node
		if ($type_of_view === self::VIEW_LIST)
			$output .= $this->setIndent($depth).$this->objectRender->renderNodeHeader($ws_params['objectsNodeName'], $ws_params);
		
		if (is_null($this->schemaToDisplay))
		{
			foreach ($objects as $key => $object)
			{
				if ($key !== 'empty')
				{
					if ($this->fieldsToDisplay  === 'minimum')
						$output .= $this->renderEntityMinimum($object, $depth);
					else
						$output .= $this->renderEntity($object, $depth);
				}
			}
		}
		else
		{
			$output .= $this->renderSchema($objects['empty'], $ws_params);
		}
		
		// If a list is asked, need to wrap with a plural node
		if ($type_of_view === self::VIEW_LIST)
			$output .= $this->setIndent($depth).$this->objectRender->renderNodeFooter($ws_params['objectsNodeName'], $ws_params);
		
		if ($override)
		$output = $this->objectRender->overrideContent($output);
		return $output;
	}

	/**
	 * Create the tree diagram with no details
	 * 
	 * @param $object create by the entity
	 * @param $depth the depth for the tree diagram
	 * @return string
	 */
	public function renderEntityMinimum($object, $depth)
	{
		$ws_params = $object->getWebserviceParameters();
		$more_attr['id'] = $object->id;
		$more_attr['xlink_resource'] = $this->wsUrl.$ws_params['objectsNodeName'].'/'.$object->id;
		$output = $this->setIndent($depth).$this->objectRender->renderNodeHeader($ws_params['objectNodeName'], $ws_params, $more_attr, false);
		return $output;
	}

	/**
	 * Build a schema blank or synopsis
	 * 
	 * @param $object create by the entity
	 * @param $ws_params webserviceParams from the entity
	 * @return string
	 */
	private function renderSchema($object, $ws_params)
	{
		$output = $this->objectRender->renderNodeHeader($ws_params['objectNodeName'], $ws_params);
		foreach ($ws_params['fields'] as $field_name => $field)
		{
			$output .= $this->renderField($object, $ws_params, $field_name, $field, 0);
		}
		if (isset($ws_params['associations']) && count($ws_params['associations']) > 0)
		{
			$this->fieldsToDisplay = 'full';
			$output .= $this->renderAssociations($object, 0, $ws_params['associations'], $ws_params);
		}
		$output .= $this->objectRender->renderNodeFooter($ws_params['objectNodeName'], $ws_params);
		return $output;
	}

	/**
	 * Build the entity detail.
	 * 
	 * @param ObjectModel $object create by the entity
	 * @param int $depth the depth for the tree diagram
	 * @return string
	 */
	public function renderEntity($object, $depth)
	{
		$output = '';
		$ws_params = $object->getWebserviceParameters();
		$output .= $this->setIndent($depth).$this->objectRender->renderNodeHeader($ws_params['objectNodeName'], $ws_params);
		
		if ($object->id != 0)
		{
			// This to add virtual Fields for a particular entity.
			$virtual_fields = $this->addVirtualFields($ws_params['objectsNodeName'], $object);
			if (!empty($virtual_fields))
				$ws_params['fields'] = array_merge($ws_params['fields'], $virtual_fields);
			
			foreach ($ws_params['fields'] as $field_name => $field)
			{
				if ($this->fieldsToDisplay === 'full' || array_key_exists($field_name, $this->fieldsToDisplay))
				{
					$field['object_id'] = $object->id;
					$field['entity_name'] = $ws_params['objectNodeName'];
					$field['entities_name'] = $ws_params['objectsNodeName'];
					$output .= $this->renderField($object, $ws_params, $field_name, $field, $depth);
				}
			}
		}
		$subexists = false;
		if (is_array($this->fieldsToDisplay))
			foreach ($this->fieldsToDisplay as $fields)
				if (is_array($fields))
					$subexists = true;

		if (isset($ws_params['associations'])
			&& ($this->fieldsToDisplay == 'full'
			|| $subexists))
		{
			$output .= $this->renderAssociations($object, $depth, $ws_params['associations'], $ws_params);
		}

		$output .= $this->setIndent($depth).$this->objectRender->renderNodeFooter($ws_params['objectNodeName'], $ws_params);
		return $output;
	}

	/**
	 * Build a field and use recursivity depend on the depth parameter.
	 * 
	 * @param ObjectModel $object create by the entity
	 * @param array $ws_params webserviceParams from the entity
	 * @param string $field_name
	 * @param array $field
	 * @param int $depth
	 * @return string
	 */
	private function renderField($object, $ws_params, $field_name, $field, $depth)
	{
		$output = '';
		$show_field = true;
		
		if (isset($ws_params['hidden_fields']) && in_array($field_name, $ws_params['hidden_fields']))
			return;

		if ($this->schemaToDisplay === 'synopsis')
		{
			$field['synopsis_details'] = $this->getSynopsisDetails($field);
			if ($field_name === 'id')
				$show_field = false;
			elseif (isset($field['setter']) && !$field['setter'])
				$show_field = false;
		}

		// don't set any value for a schema
		if (isset($field['synopsis_details']) || $this->schemaToDisplay === 'blank')
		{
			$field['value'] = '';
			if (isset($field['xlink_resource']))
				 unset($field['xlink_resource']);
		}
		elseif (isset($field['getter']) && $object != null && method_exists($object, $field['getter']))
			$field['value'] = $object->$field['getter']();
		elseif (!isset($field['value']))
			$field['value'] = $object->$field_name;
		
		// this apply specific function for a particular field on a choosen entity
		$field = $this->overrideSpecificField($ws_params['objectsNodeName'], $field_name, $field, $object, $ws_params);
		
		// don't display informations for a not existant id
		if (substr($field['sqlId'], 0, 3) == 'id_' && $field['value'] == 0)
		{
			$field['value'] = '';
			// delete the xlink except for schemas
			if (isset($field['xlink_resource']) && is_null($this->schemaToDisplay))
				 unset($field['xlink_resource']);
		}
		// set "id" for each node name which display the id of the entity
		if ($field_name === 'id')
			$field['sqlId'] = 'id';
		
		
		// don't display the node id for a synopsis schema
		if ($show_field)
			$output .= $this->setIndent($depth-1).$this->objectRender->renderField($field);
		return $output;
	}

	/**
	 * 
	 * 
	 * @param $object
	 * @param $depth
	 * @param $associations
	 * @param $ws_params
	 * @return string
	 */
	private function renderAssociations($object, $depth, $associations, $ws_params)
	{
		$output = $this->objectRender->renderAssociationWrapperHeader();
		foreach ($associations as $assoc_name => $association)
		{
			if ($this->fieldsToDisplay == 'full' || is_array($this->fieldsToDisplay) && array_key_exists($assoc_name, $this->fieldsToDisplay))
			{
				$getter = $association['getter'];
				$objects_assoc = array();
				
				$fields_assoc = array();
				if (isset($association['fields']))
					$fields_assoc = $association['fields']; 
				
				$parent_details = array(
						'object_id'	=> $object->id,
						'entity_name'	=> $ws_params['objectNodeName'],
						'entities_name'	=> $ws_params['objectsNodeName'],
					);
				
				if (method_exists($object, $getter) && is_null($this->schemaToDisplay))
				{
					$association_resources = $object->$getter();
					if (is_array($association_resources) && !empty($association_resources))
					{
						foreach ($association_resources as $association_resource)
						{
							$objects_assoc[] = $association_resource;
						}
					}
				}
				else
				{
					$objects_assoc[] = '';
				}
				
				$class_name = null;
				if (isset($this->wsResource[$assoc_name]['class']) && class_exists($this->wsResource[$assoc_name]['class'], true))
					$class_name = $this->wsResource[$assoc_name]['class'];
				$output_details = '';
				foreach ($objects_assoc as $object_assoc)
				{
					if ($depth == 0 || $class_name === null)
					{
						$value = null;
						if (!empty($object_assoc))
							$value = $object_assoc;
						if (empty($fields_assoc))
							$fields_assoc = array(array('id' => $value['id']));
						$output_details .= $this->renderFlatAssociation($object, $depth, $assoc_name, $association['resource'], $fields_assoc, $value, $parent_details);
					}
					else
					{
						foreach ($object_assoc as $id)
						{
							if ($class_name !== null)
							{
								$child_object = new $class_name($id);
								$output_details .= $this->renderEntity($child_object, ($depth-2 ? 0 : $depth-2));
							}
						}
					}
				}
				if ($output_details != '')
				{
					$output .= $this->setIndent($depth).$this->objectRender->renderAssociationHeader($object, $ws_params, $assoc_name);
					$output .= $output_details;
					$output .= $this->setIndent($depth).$this->objectRender->renderAssociationFooter($object, $ws_params, $assoc_name);
				}
				else
				{
					$output .= $this->setIndent($depth).$this->objectRender->renderAssociationHeader($object, $ws_params, $assoc_name, true);
				}
			}
		}
		$output .= $this->objectRender->renderAssociationWrapperFooter();
		return $output;
	}
	
	private function renderFlatAssociation($object, $depth, $assoc_name, $resource_name, $fields_assoc, $object_assoc, $parent_details)
	{
		$output = '';
		$more_attr = array();
		if (isset($this->wsResource[$assoc_name]) && is_null($this->schemaToDisplay))
		{
			if ($assoc_name == 'images')
				$more_attr['xlink_resource'] = $this->wsUrl.$assoc_name.'/'.$parent_details['entities_name'].'/'.$parent_details['object_id'].'/'.$object_assoc['id'];
			else
				$more_attr['xlink_resource'] = $this->wsUrl.$assoc_name.'/'.$object_assoc['id'];
		}
		$output .= $this->setIndent($depth-1).$this->objectRender->renderNodeHeader($resource_name, array(), $more_attr);
		
		foreach ($fields_assoc as $field_name=>$field)
		{
			if (!is_array($this->fieldsToDisplay) || in_array($field_name, $this->fieldsToDisplay[$assoc_name]))
			{
				if ($field_name == 'id' && !isset($field['sqlId']))
				{
					$field['sqlId'] = 'id';
					$field['value'] = $object_assoc['id'];
				}
				elseif (!isset($field['sqlId']))
				{
					$field['sqlId'] = $field_name;
					$field['value'] = $object_assoc[$field_name];
				}
				$field['entities_name'] = $assoc_name;
				$field['entity_name'] = $resource_name;
				
				if (!is_null($this->schemaToDisplay))
					$field['synopsis_details'] = $this->getSynopsisDetails($field);
				
				$output .= $this->setIndent($depth-1).$this->objectRender->renderField($field);
			}
		}
		$output .= $this->setIndent($depth-1).$this->objectRender->renderNodeFooter($resource_name, array());
		return $output;
	}
	
	public function setIndent($depth)
	{
		$string = '';
		$number_of_tabs = $this->depth - $depth;
		for ($i = 0; $i < $number_of_tabs; $i++)
			$string .= "\t";
		return $string;
	}
	
	public function getSynopsisDetails($field)
	{
		$arr_details = '';
		if (array_key_exists('required', $field) && $field['required'])
			$arr_details['required'] = 'true';
		if (array_key_exists('maxSize', $field) && $field['maxSize'])
			$arr_details['maxSize'] = $field['maxSize'];
		if (array_key_exists('validateMethod', $field) && $field['validateMethod'])
			$arr_details['format'] = $field['validateMethod'];
		return $arr_details;
	}
	
	/**
	 * 
	 * @param string|object $object
	 * @param string $method
	 * @return $this
	 */
	public function setSpecificField($object, $method, $field_name, $entity_name)
	{
		try {
			$this->validateObjectAndMethod($object, $method);
		} catch (WebserviceException $e) {
			throw $e;
		}
		
		$this->specificFields[$field_name] = array('entity'=>$entity_name, 'object' => $object, 'method' => $method, 'type' => gettype($object));
		return $this;	
	}
	private function validateObjectAndMethod($object, $method)
	{
		if (is_string($object) && !class_exists($object))
			throw new WebserviceException ('The object you want to set in '.__METHOD__.' is not allowed.', array(98, 500));
		if (!method_exists($object, $method))
			throw new WebserviceException ('The method you want to set in '.__METHOD__.' is not allowed.', array(99, 500));
	}
	public function getSpecificField()
	{
		return $this->specificFields;
	}
	private function overrideSpecificField($entity_name, $field_name, $field, $entity_object, $ws_params)
	{
		if (array_key_exists($field_name, $this->specificFields) && $this->specificFields[$field_name]['entity'] == $entity_name)
		{
			if ($this->specificFields[$field_name]['type'] == 'string')
				$object = new $this->specificFields[$field_name]['object']();
			elseif ($this->specificFields[$field_name]['type'] == 'object')
				$object= $this->specificFields[$field_name]['object'];
			
			$field = $object->{$this->specificFields[$field_name]['method']}($field, $entity_object, $ws_params);
		}
		return $field;
	}
	public function setVirtualField($object, $method, $entity_name, $parameters)
	{
		try {
			$this->validateObjectAndMethod($object, $method);
		} catch (WebserviceException $e) {
			throw $e;
		}
		
		$this->virtualFields[$entity_name][] = array('parameters' => $parameters, 'object' => $object, 'method' => $method, 'type' => gettype($object));
	}
	public function getVirtualFields()
	{
		return $this->virtualFields;
	}
	public function addVirtualFields($entity_name, $entity_object)
	{
		$arr_return = array();
		$virtual_fields = $this->getVirtualFields();
		if (array_key_exists($entity_name, $virtual_fields))
		{
			foreach ($virtual_fields[$entity_name] as $function_infos)
			{
				if ($function_infos['type'] == 'string')
					$object = new $function_infos['object']();
				elseif ($function_infos['type'] == 'object')
					$object= $function_infos['object'];
				
				$return_fields = $object->{$function_infos['method']}($entity_object, $function_infos['parameters']);
				foreach ($return_fields as $field_name => $value)
				{
					if (Validate::isConfigName($field_name))
						$arr_return[$field_name] = $value;
					else
						throw new WebserviceException('Name for the virtual field is not allow', array(128, 400));
				}
			}
		}
		return $arr_return;
	}
	
	public function setFieldsToDisplay($fields)
	{
		$this->fieldsToDisplay = $fields;
	}
}