Template/src/functions/functions.php - zetacomponents - Git at Google

 <?php
 /**
  * File containing the ezcTemplateFunctions class
  *
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership.  The ASF licenses this file
  * to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance
  * with the License.  You may obtain a copy of the License at
  *
  *   http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  * KIND, either express or implied.  See the License for the
  * specific language governing permissions and limitations
  * under the License.
  *
  * @package Template
  * @version //autogen//
  * @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
  * @access private
  */

 /**
  * This class translates Template functions to PHP functions. If the function
  * could not directly mapped to a PHP internal function, it calls a static
  * function from the Template component, implementing the desired behavior.
  *
  * @package Template
  * @version //autogen//
  * @access private
  */
 class ezcTemplateFunctions
 {
     /**
      * Keeps the translations from a specific regular expression match to a class name.
      * E.g. Everything that starts with "str_" is translated to ezcTemplateStringFunctions.
      *
      * The 'functions_to_class.php' is read for the translations.
      *
      * @var array(string=>string) $functionToClass
      */
     protected $functionToClass;

     /**
      * Keeps a reference to the Template parser.
      *
      * @var ezcTemplateParser $parser
      */
     private $parser = null;

     /**
      * Constructs a new ezcTemplateFunctions
      *
      * @param ezcTemplateParser $parser
      */
     public function __construct( ezcTemplateParser $parser )
     {
         $this->parser = $parser;
         $this->functionToClass = include( "function_to_class.php" );
     }

     /**
      * Returns (a part of) an AST-tree that makes a function call to the function $name with
      * the parameters $parameters.
      *
      * @param string $name
      * @param array(ezcTemplateAstNode) $parameters
      * @return array(ezcTemplateAstNode)
      */
     protected static function functionCall( $name, $parameters )
     {
         return array( "ezcTemplateFunctionCallAstNode", array( $name, array( "_array", $parameters ) ) );
     }

     /**
      * Returns an Literal AST-node with the value $val.
      *
      * @param mixed $val
      * @return array(ezcTemplateAstNode)
      */
     protected static function value( $val )
     {
         return array( "ezcTemplateLiteralAstNode", array( $val ) );
     }

     /**
      * Returns an Constant AST-node with the value $val.
      *
      * @param mixed $val
      * @return array(ezcTemplateAstNode)
      */
     protected static function constant( $val )
     {
         return array( "ezcTemplateConstantAstNode", array( $val ) );
     }

     /**
      * Concats (with ezcTemplateConcatOperatorAstNode) the two AST trees: $left and $right together.
      *
      * @param ezcTemplateAstNode $left
      * @param ezcTemplateAstNode $right
      * @return array(ezcTemplateAstNode)
      */
     protected static function concat( $left, $right )
     {
         return array( "ezcTemplateConcatOperatorAstNode", array( $left, $right ) );
     }

     /**
      * Returns true if the given parameter $parameter should be substituted with an ezcTemplateAstNode.
      *
      * @param string $parameter
      * @return bool
      */
     protected static function isSubstitution( $parameter )
     {
         return ( strpos( $parameter, "%" ) !== false );
     }

     /**
      * Returns true if the given parameter is optional.
      *
      * @param string $parameter
      * @return bool
      */
     protected static function isOptional( $parameter )
     {
         return $parameter[0] == "[";
     }

     /**
      * Returns true if the given parameter represents one or more parameters.
      *
      * @param string $parameter
      * @return bool
      */
     protected static function isMany( $parameter )
     {
         return ( $parameter[1] == "." && $parameter[2] == "." );
     }

     /**
      * Returns the given amount of parameters plus the optional remaining parameters.
      *
      * @param array(string) $parameters
      * @return int
      */
     protected static function countParameters( $parameters )
     {
         $total = sizeof( $parameters );
         if ( isset( $parameterMap[ "__rest__" ] ) )
         {
             $total += sizeof( $parametersMap["__rest__"] ) - 1;
         }

         return $total;
     }

     /**
      * Returns true if the given AST node is a variable; thus a value can be assigned.
      *
      * @param ezcTemplateAstNode $ast
      * @return bool
      */
     protected static function isVariable( $ast )
     {
         if ( $ast instanceof ezcTemplateVariableAstNode ||
             $ast instanceof ezcTemplateReferenceOperatorAstNode  ||
             $ast instanceof ezcTemplateArrayFetchOperatorAstNode )
         {
             return true;
         }

         return false;
     }

     /**
      * Checks the type (currently only Variable) for a given AST node.
      * If the type doesn't match, an exception is thrown.
      *
      * @param string $defined
      * @param ezcTemplateAstNode $givenAst
      * @param string $functionName  Only important for the error message.
      * @param int $parameterNumber  Only important for the error message.
      *
      * @throws ezcTemplateException if the function type is incorrect.
      *
      * @return void
      */
     protected static function checkType( $defined, $givenAst, $functionName, $parameterNumber )
     {
         $s = explode( ":", $defined );
         $type = sizeof( $s ) > 1 ? $s[1] : null;

         if ( $type !== null && $type == "Variable" )
         {
             if ( !self::isVariable( $givenAst ) )
             {
                 throw new ezcTemplateException( "The function '$functionName' expects parameter ". ($parameterNumber + 1)." to be a variable." );
             }
         }
     }

     /**
      * Creates a new instantance of the given $className string with the parameters $functionParameters.
      *
      * If the class name is equal to "_array", it will just return the $functionParameters.
      *
      * @param string $className
      * @param ezcTemplateAstNode $functionParameters
      * @return ezcTemplateAstNode
      */
     protected function createObject( $className, $functionParameters )
     {
         if ( $className == "_array" )
         {
             return $functionParameters;
         }

         return call_user_func_array(
             array( new ReflectionClass( $className ), 'newInstance' ), $functionParameters );
     }


     /**
      * Translates a function definition to a real AST tree. The function definition contains
      * some virtual nodes that needs to be translated.
      *
      * @param string $functionName
      * @param ezcTemplateAstNode $struct
      * @param array(string=>ezcTemplateAstNode) $parameterMap
      * @param bool $usedRest Initially set to false and may be set to true.
      * @return ezcTemplateAstNode
      */
     protected function processAst( $functionName, $struct, $parameterMap, &$usedRest )
     {
         $pOut = array();
         foreach ( $struct[1] as $pIn )
         {
             if ( is_array( $pIn ) )
             {
                 $pOut[] =  $this->processAst( $functionName, $pIn, $parameterMap, $usedRest );
             }
             else
             {
                 if ( self::isSubstitution( $pIn ) )
                 {
                     // Skip the optional parameter if the value is null.
                     if ( $parameterMap[$pIn] !== null )
                     {
                         $pOut[] = $parameterMap[ $pIn ];

                         if ( self::isMany( $pIn ) && isset( $parameterMap[ "__rest__" ]  ) )
                         {
                             $usedRest = true;
                             foreach ( $parameterMap[ "__rest__" ] as $restParameter )
                             {
                                 $pOut[] = $restParameter;
                             }
                         }
                     }
                     elseif ( !self::isOptional( $pIn ) )
                     {
                         throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_EXPECT_PARAMETER, $functionName, $pIn ) );
                     }
                 }
                 else
                 {
                     // No substitution needed.
                     $pOut[] = $pIn;
                 }
             }
         }
         return $this->createObject( $struct[0], $pOut );
     }

     /**
      * Translates a function definition to a real AST tree. The function definition contains
      * some virtual nodes that needs to be translated.
      *
      * @param string $functionName
      * @param array(mixed) $functionDefinition
      * @param array(ezcTemplateAstNode) $processedParameters
      * @return ezcTemplateAstNode
      */
     protected function createAstNodes( $functionName, $functionDefinition, $processedParameters )
     {
         $index = sizeof( $functionDefinition ) == 3  ? 1 : 0;

         $realParameters = sizeof( $processedParameters );
         $definedParameters = self::countParameters( $functionDefinition[ $index ] );

         // Map the parameters from the function definition to the given (real) parameters.
         $parameterMap = array();
         $i = 0;
         foreach ( $functionDefinition[ $index ] as $p )
         {
             if ( self::isOptional( $p ) && $realParameters < $i )
             {
                 // We should skip this parameter.
                 $parameterMap[$p] = null;
             }
             else
             {
                 $parameterMap[$p] = null;

                 if ( isset( $processedParameters[$i] ) )
                 {
                     $parameterMap[$p] = $processedParameters[$i];
                     self::checkType( $p, $processedParameters[$i], $functionName, $i );
                 }

                 $i++;
             }
         }

         // Remaining parameters are stored in the "__rest__".
         $hasRest = false;
         while ( isset( $processedParameters[$i] ) )
         {
             $parameterMap[ "__rest__" ][] = $processedParameters[$i++];
             $hasRest = true;
         }

         $usedRest = false;
         $ast = $this->processAst( $functionName, $functionDefinition[ $index + 1 ], $parameterMap, $usedRest );

         if ( $hasRest && !$usedRest )
         {
             throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_TOO_MANY_PARAMETERS, $functionName ) );
         }


         if ( sizeof( $functionDefinition ) == 3 )
         {
             $ast->typeHint = $functionDefinition[0];
         }
         else
         {
             $ast->typeHint = ezcTemplateAstNode::TYPE_ARRAY | ezcTemplateAstNode::TYPE_VALUE;
         }

         return new ezcTemplateParenthesisAstNode( $ast );
     }

     /**
      * Returns the class that may implement this function $functionName.
      *
      * @param string $functionName
      * @return string
      */
     public function getClass( $functionName )
     {
         foreach ( $this->functionToClass as $func => $class )
         {
             if ( preg_match( $func, $functionName ) )
             {
                 return $class;
             }
         }

         return null;
     }

     /**
      * Returns a custom function definition if the given function name $name is a custom function,
      * otherwise return false.
      *
      * @param string $name
      * @return ezcTemplateCustomFunctionDefinition
      */
     public function getCustomFunction( $name )
     {
         foreach ( $this->parser->template->usedConfiguration->customFunctions as $class )
         {
             $def = call_user_func( array( $class, "getCustomFunctionDefinition" ),  $name );

             if ( $def instanceof ezcTemplateCustomFunctionDefinition )
             {
                 return $def;
             }
         }

         return false;
     }


     /**
      * Checks if the definition is correct. It returns nothing if it's correct, and
      * throws an exception otherwise.
      *
      * @param ezcTemplateCustomFunctionDefintion $definition
      * @param ReflectionParameters $reflectionParameters
      * @throws ezcTemplateException if the given definition is incorrect.
      * @return void
      */
     protected function checkDefinition( $definition, $reflectionParameters )
     {
         if ( !isset( $definition->parameters ) || $definition->parameters === false )
         {
             return;
         }

         $i = 0;
         $foundOptionalParameter = false;
         foreach ( $definition->parameters as $p )
         {
             if ( !isset($reflectionParameters[$i]) )
             {
                 throw new ezcTemplateException( sprintf(ezcTemplateSourceToTstErrorMessages::MSG_INVALID_DEFINITION_PARAMETER_DOES_NOT_EXIST, $i + 1));
             }

             if ( $p[0] == "[" )
             {
                 if ( !$reflectionParameters[$i]->isOptional() )
                 {
                     throw new ezcTemplateException(sprintf(ezcTemplateSourceToTstErrorMessages::MSG_INVALID_DEFINITION_PARAMETER_OPTIONAL, $i + 1));
                 }

                 $foundOptionalParameter = true;
             }
             else
             {
                 if ($foundOptionalParameter)
                 {
                     throw new ezcTemplateException(ezcTemplateSourceToTstErrorMessages::MSG_INVALID_DEFINITION_EXPECT_OPTIONAL_PARAMETER);
                 }
             }

             $i++;
         }
     }

     /**
      * Counts how many parameters are required.
      *
      * @param ezcTemplateCustomFunctionDefintion $definition
      * @param ReflectionParameters $reflectionParameters
      * @return int
      */
     protected function countRequiredParameters( $definition, $reflectionParameters )
     {
         $requiredParameters = 0;

         foreach ( $reflectionParameters as $p )
         {
             if ( !$p->isOptional() )
             {
                 $requiredParameters++;
             }
         }

         return $requiredParameters;
     }

     /**
      * Counts the total amount of parameters.
      *
      * @param ezcTemplateCustomFunctionDefintion $definition
      * @param ReflectionParameters $reflectionParameters
      * @return int
      */
     protected function countTotalParameters($definition, $reflectionParameters)
     {
         return sizeof( $reflectionParameters );
     }

     /**
      * Checks the given parameters.
      *
      * @param ezcTemplateCustomFunctionDefintion $definition
      * @param ReflectionParameters $reflectionParameters
      * @param array(ezcTemplateAstNode) $parameters
      * @param string $functionName
      * @return int
      */
     protected function checkGivenParameters( $definition, $reflectionParameters, $parameters, $functionName )
     {
         $givenParameters = sizeof($parameters);

         if ( $givenParameters < $this->countRequiredParameters($definition, $reflectionParameters) )
         {
             throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_EXPECT_PARAMETER, $functionName, $definition->parameters[$givenParameters]));
         }

         if ( !$definition->variableArgumentList && $givenParameters > $this->countTotalParameters($definition, $reflectionParameters) )
         {
             throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_TOO_MANY_PARAMETERS, $functionName ) );
         }
     }

     /**
      * Orders the parameters.
      *
      * @param ReflectionParameters $reflectionParameters
      * @param array(ezcTemplateAstNode) $parameters
      * @param string $functionName
      * @return array(ezcTemplateAstNode)
      */
     protected function orderParameters($reflectionParameters, $parameters, $functionName)
     {
         // First assign the named parameters, thereafter fill in the rest.
         $newParameters = array();

         // Process the named parameters.
         $maxNr = 0;

         // Named parameters.
         foreach ($parameters as $name => $value)
         {
             if (!is_int($name))
             {
                 $found = false;
                 $nr = 0;

                 foreach ( $reflectionParameters as $rp)
                 {
                     if ( $rp->getName() === $name )
                     {
                         $found = true;
                         break;
                     }

                     $nr++;
                 }

                 if ( !$found)
                 {
                     throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_NAMED_PARAMETER_NOT_FOUND, $name, $functionName  ) );
                 }

                 $newParameters[$nr] = $value;
                 $maxNr = max($nr, $maxNr);
             }
         }
         ksort($newParameters, SORT_NUMERIC);

         $i = 0;
         foreach ($parameters as $name => $value)
         {
             if (is_int($name))
             {
                 while ( isset($newParameters[$i])) $i++;

                 $newParameters[$i] = $value;
             }

             $i++;
         }

         // Search for 'holes'.
         for($i = 0; $i < $maxNr; $i++)
         {
             if ( !isset( $newParameters[$i]) )
             {
                 if ( !$reflectionParameters[$i]->isDefaultValueAvailable() )
                 {
                     throw new ezcTemplateException( sprintf("Parameter %s is not given and has not a default value.", $i + 1) );
                 }
                 else
                 {
                     $newParameters[$i] = new ezcTemplateLiteralAstNode( $reflectionParameters[$i]->getDefaultValue() );
                 }
             }
         }
         ksort($newParameters, SORT_NUMERIC);

         return $newParameters;
     }

     /**
      * Returns the reflection parameters.
      *
      * @param ezcTemplateCustomFunctionDefintion $definition
      * @return ReflectionParameters
      */
     protected function getReflectionParameters( $definition )
     {
         if ( !isset($definition->class) || $definition->class  === false )
         {
             $rm = new ReflectionFunction( $definition->method );
         }
         else
         {
             $rc = new ReflectionClass( $definition->class );
             $rm = $rc->getMethod($definition->method);
         }

         return $rm->getParameters();
     }

     /**
      * Returns the corresponding AST tree to the function name $functionName and its parameters.
      *
      * The function name will, most likely, be translated from a Template function name to
      * the PHP function. The parameters are ordered, if needed.
      *
      * @param string $functionName
      * @param array(ezcTemplateAstNode) $parameters
      * @throws ezcTemplateException if the parameters are not valid (Too many, not enough parameters, etc).
      * @return ezcTemplateAstNode
      */
     public function getAstTree( $functionName, $parameters )
     {
         // Try the built-in template functions.
         $class = $this->getClass( $functionName );

         if ( $class !== null )
         {
             $f = call_user_func( array( $class, "getFunctionSubstitution"), $functionName, $parameters );
             if ( $f !== null ) return $this->createAstNodes( $functionName, $f, $parameters );
         }

         // Try the custom template functions.
         $def = $this->getCustomFunction( $functionName );

         if ( $def !== false )
         {
             $reflectionParameters = $this->getReflectionParameters( $def );

             $a = new ezcTemplateFunctionCallAstNode( ( $def->class ? ( $def->class . "::" ) : "" ) . $def->method);
             $a->checkAndSetTypeHint();

             if ( isset($def->sendTemplateObject) && $def->sendTemplateObject )
             {
                 array_shift($reflectionParameters);
                 $a->appendParameter( new ezcTemplateVariableAstNode("this->template") );
             }

             $this->checkDefinition($def, $reflectionParameters);
             $this->checkGivenParameters($def, $reflectionParameters, $parameters, $functionName);

             $parameters = $this->orderParameters( $reflectionParameters, $parameters, $functionName);


             foreach ( $parameters as $p)
             {
                 $a->appendParameter( $p );
             }

             return $a;
         }

         throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_UNKNOWN_FUNCTION, $functionName ) );
     }

     /**
      * Subclasses need to implement this method.
      *
      * @param string $functionName
      * @param array(ezcTemplateAstNode) $parameters
      * @throws ezcTemplateInternalException if the subclass does not implement this method.
      * @return array(mixed)
      */
     public static function getFunctionSubstitution( $functionName, $parameters )
     {
         throw new ezcTemplateInternalException( "Subclasses need to implement the getFunctionSubstitution method." );
     }
 }
 ?>
	<?php
	/**
	* File containing the ezcTemplateFunctions class
	*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*
	* @package Template
	* @version //autogen//
	* @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
	* @access private
	*/

	/**
	* This class translates Template functions to PHP functions. If the function
	* could not directly mapped to a PHP internal function, it calls a static
	* function from the Template component, implementing the desired behavior.
	*
	* @package Template
	* @version //autogen//
	* @access private
	*/
	class ezcTemplateFunctions
	{
	/**
	* Keeps the translations from a specific regular expression match to a class name.
	* E.g. Everything that starts with "str_" is translated to ezcTemplateStringFunctions.
	*
	* The 'functions_to_class.php' is read for the translations.
	*
	* @var array(string=>string) $functionToClass
	*/
	protected $functionToClass;

	/**
	* Keeps a reference to the Template parser.
	*
	* @var ezcTemplateParser $parser
	*/
	private $parser = null;

	/**
	* Constructs a new ezcTemplateFunctions
	*
	* @param ezcTemplateParser $parser
	*/
	public function __construct( ezcTemplateParser $parser )
	{
	$this->parser = $parser;
	$this->functionToClass = include( "function_to_class.php" );
	}

	/**
	* Returns (a part of) an AST-tree that makes a function call to the function $name with
	* the parameters $parameters.
	*
	* @param string $name
	* @param array(ezcTemplateAstNode) $parameters
	* @return array(ezcTemplateAstNode)
	*/
	protected static function functionCall( $name, $parameters )
	{
	return array( "ezcTemplateFunctionCallAstNode", array( $name, array( "_array", $parameters ) ) );
	}

	/**
	* Returns an Literal AST-node with the value $val.
	*
	* @param mixed $val
	* @return array(ezcTemplateAstNode)
	*/
	protected static function value( $val )
	{
	return array( "ezcTemplateLiteralAstNode", array( $val ) );
	}

	/**
	* Returns an Constant AST-node with the value $val.
	*
	* @param mixed $val
	* @return array(ezcTemplateAstNode)
	*/
	protected static function constant( $val )
	{
	return array( "ezcTemplateConstantAstNode", array( $val ) );
	}

	/**
	* Concats (with ezcTemplateConcatOperatorAstNode) the two AST trees: $left and $right together.
	*
	* @param ezcTemplateAstNode $left
	* @param ezcTemplateAstNode $right
	* @return array(ezcTemplateAstNode)
	*/
	protected static function concat( $left, $right )
	{
	return array( "ezcTemplateConcatOperatorAstNode", array( $left, $right ) );
	}

	/**
	* Returns true if the given parameter $parameter should be substituted with an ezcTemplateAstNode.
	*
	* @param string $parameter
	* @return bool
	*/
	protected static function isSubstitution( $parameter )
	{
	return ( strpos( $parameter, "%" ) !== false );
	}

	/**
	* Returns true if the given parameter is optional.
	*
	* @param string $parameter
	* @return bool
	*/
	protected static function isOptional( $parameter )
	{
	return $parameter[0] == "[";
	}

	/**
	* Returns true if the given parameter represents one or more parameters.
	*
	* @param string $parameter
	* @return bool
	*/
	protected static function isMany( $parameter )
	{
	return ( $parameter[1] == "." && $parameter[2] == "." );
	}

	/**
	* Returns the given amount of parameters plus the optional remaining parameters.
	*
	* @param array(string) $parameters
	* @return int
	*/
	protected static function countParameters( $parameters )
	{
	$total = sizeof( $parameters );
	if ( isset( $parameterMap[ "__rest__" ] ) )
	{
	$total += sizeof( $parametersMap["__rest__"] ) - 1;
	}

	return $total;
	}

	/**
	* Returns true if the given AST node is a variable; thus a value can be assigned.
	*
	* @param ezcTemplateAstNode $ast
	* @return bool
	*/
	protected static function isVariable( $ast )
	{
	if ( $ast instanceof ezcTemplateVariableAstNode \|\|
	$ast instanceof ezcTemplateReferenceOperatorAstNode \|\|
	$ast instanceof ezcTemplateArrayFetchOperatorAstNode )
	{
	return true;
	}

	return false;
	}

	/**
	* Checks the type (currently only Variable) for a given AST node.
	* If the type doesn't match, an exception is thrown.
	*
	* @param string $defined
	* @param ezcTemplateAstNode $givenAst
	* @param string $functionName Only important for the error message.
	* @param int $parameterNumber Only important for the error message.
	*
	* @throws ezcTemplateException if the function type is incorrect.
	*
	* @return void
	*/
	protected static function checkType( $defined, $givenAst, $functionName, $parameterNumber )
	{
	$s = explode( ":", $defined );
	$type = sizeof( $s ) > 1 ? $s[1] : null;

	if ( $type !== null && $type == "Variable" )
	{
	if ( !self::isVariable( $givenAst ) )
	{
	throw new ezcTemplateException( "The function '$functionName' expects parameter ". ($parameterNumber + 1)." to be a variable." );
	}
	}
	}

	/**
	* Creates a new instantance of the given $className string with the parameters $functionParameters.
	*
	* If the class name is equal to "_array", it will just return the $functionParameters.
	*
	* @param string $className
	* @param ezcTemplateAstNode $functionParameters
	* @return ezcTemplateAstNode
	*/
	protected function createObject( $className, $functionParameters )
	{
	if ( $className == "_array" )
	{
	return $functionParameters;
	}

	return call_user_func_array(
	array( new ReflectionClass( $className ), 'newInstance' ), $functionParameters );
	}


	/**
	* Translates a function definition to a real AST tree. The function definition contains
	* some virtual nodes that needs to be translated.
	*
	* @param string $functionName
	* @param ezcTemplateAstNode $struct
	* @param array(string=>ezcTemplateAstNode) $parameterMap
	* @param bool $usedRest Initially set to false and may be set to true.
	* @return ezcTemplateAstNode
	*/
	protected function processAst( $functionName, $struct, $parameterMap, &$usedRest )
	{
	$pOut = array();
	foreach ( $struct[1] as $pIn )
	{
	if ( is_array( $pIn ) )
	{
	$pOut[] = $this->processAst( $functionName, $pIn, $parameterMap, $usedRest );
	}
	else
	{
	if ( self::isSubstitution( $pIn ) )
	{
	// Skip the optional parameter if the value is null.
	if ( $parameterMap[$pIn] !== null )
	{
	$pOut[] = $parameterMap[ $pIn ];

	if ( self::isMany( $pIn ) && isset( $parameterMap[ "__rest__" ] ) )
	{
	$usedRest = true;
	foreach ( $parameterMap[ "__rest__" ] as $restParameter )
	{
	$pOut[] = $restParameter;
	}
	}
	}
	elseif ( !self::isOptional( $pIn ) )
	{
	throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_EXPECT_PARAMETER, $functionName, $pIn ) );
	}
	}
	else
	{
	// No substitution needed.
	$pOut[] = $pIn;
	}
	}
	}
	return $this->createObject( $struct[0], $pOut );
	}

	/**
	* Translates a function definition to a real AST tree. The function definition contains
	* some virtual nodes that needs to be translated.
	*
	* @param string $functionName
	* @param array(mixed) $functionDefinition
	* @param array(ezcTemplateAstNode) $processedParameters
	* @return ezcTemplateAstNode
	*/
	protected function createAstNodes( $functionName, $functionDefinition, $processedParameters )
	{
	$index = sizeof( $functionDefinition ) == 3 ? 1 : 0;

	$realParameters = sizeof( $processedParameters );
	$definedParameters = self::countParameters( $functionDefinition[ $index ] );

	// Map the parameters from the function definition to the given (real) parameters.
	$parameterMap = array();
	$i = 0;
	foreach ( $functionDefinition[ $index ] as $p )
	{
	if ( self::isOptional( $p ) && $realParameters < $i )
	{
	// We should skip this parameter.
	$parameterMap[$p] = null;
	}
	else
	{
	$parameterMap[$p] = null;

	if ( isset( $processedParameters[$i] ) )
	{
	$parameterMap[$p] = $processedParameters[$i];
	self::checkType( $p, $processedParameters[$i], $functionName, $i );
	}

	$i++;
	}
	}

	// Remaining parameters are stored in the "__rest__".
	$hasRest = false;
	while ( isset( $processedParameters[$i] ) )
	{
	$parameterMap[ "__rest__" ][] = $processedParameters[$i++];
	$hasRest = true;
	}

	$usedRest = false;
	$ast = $this->processAst( $functionName, $functionDefinition[ $index + 1 ], $parameterMap, $usedRest );

	if ( $hasRest && !$usedRest )
	{
	throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_TOO_MANY_PARAMETERS, $functionName ) );
	}


	if ( sizeof( $functionDefinition ) == 3 )
	{
	$ast->typeHint = $functionDefinition[0];
	}
	else
	{
	$ast->typeHint = ezcTemplateAstNode::TYPE_ARRAY \| ezcTemplateAstNode::TYPE_VALUE;
	}

	return new ezcTemplateParenthesisAstNode( $ast );
	}

	/**
	* Returns the class that may implement this function $functionName.
	*
	* @param string $functionName
	* @return string
	*/
	public function getClass( $functionName )
	{
	foreach ( $this->functionToClass as $func => $class )
	{
	if ( preg_match( $func, $functionName ) )
	{
	return $class;
	}
	}

	return null;
	}

	/**
	* Returns a custom function definition if the given function name $name is a custom function,
	* otherwise return false.
	*
	* @param string $name
	* @return ezcTemplateCustomFunctionDefinition
	*/
	public function getCustomFunction( $name )
	{
	foreach ( $this->parser->template->usedConfiguration->customFunctions as $class )
	{
	$def = call_user_func( array( $class, "getCustomFunctionDefinition" ), $name );

	if ( $def instanceof ezcTemplateCustomFunctionDefinition )
	{
	return $def;
	}
	}

	return false;
	}


	/**
	* Checks if the definition is correct. It returns nothing if it's correct, and
	* throws an exception otherwise.
	*
	* @param ezcTemplateCustomFunctionDefintion $definition
	* @param ReflectionParameters $reflectionParameters
	* @throws ezcTemplateException if the given definition is incorrect.
	* @return void
	*/
	protected function checkDefinition( $definition, $reflectionParameters )
	{
	if ( !isset( $definition->parameters ) \|\| $definition->parameters === false )
	{
	return;
	}

	$i = 0;
	$foundOptionalParameter = false;
	foreach ( $definition->parameters as $p )
	{
	if ( !isset($reflectionParameters[$i]) )
	{
	throw new ezcTemplateException( sprintf(ezcTemplateSourceToTstErrorMessages::MSG_INVALID_DEFINITION_PARAMETER_DOES_NOT_EXIST, $i + 1));
	}

	if ( $p[0] == "[" )
	{
	if ( !$reflectionParameters[$i]->isOptional() )
	{
	throw new ezcTemplateException(sprintf(ezcTemplateSourceToTstErrorMessages::MSG_INVALID_DEFINITION_PARAMETER_OPTIONAL, $i + 1));
	}

	$foundOptionalParameter = true;
	}
	else
	{
	if ($foundOptionalParameter)
	{
	throw new ezcTemplateException(ezcTemplateSourceToTstErrorMessages::MSG_INVALID_DEFINITION_EXPECT_OPTIONAL_PARAMETER);
	}
	}

	$i++;
	}
	}

	/**
	* Counts how many parameters are required.
	*
	* @param ezcTemplateCustomFunctionDefintion $definition
	* @param ReflectionParameters $reflectionParameters
	* @return int
	*/
	protected function countRequiredParameters( $definition, $reflectionParameters )
	{
	$requiredParameters = 0;

	foreach ( $reflectionParameters as $p )
	{
	if ( !$p->isOptional() )
	{
	$requiredParameters++;
	}
	}

	return $requiredParameters;
	}

	/**
	* Counts the total amount of parameters.
	*
	* @param ezcTemplateCustomFunctionDefintion $definition
	* @param ReflectionParameters $reflectionParameters
	* @return int
	*/
	protected function countTotalParameters($definition, $reflectionParameters)
	{
	return sizeof( $reflectionParameters );
	}

	/**
	* Checks the given parameters.
	*
	* @param ezcTemplateCustomFunctionDefintion $definition
	* @param ReflectionParameters $reflectionParameters
	* @param array(ezcTemplateAstNode) $parameters
	* @param string $functionName
	* @return int
	*/
	protected function checkGivenParameters( $definition, $reflectionParameters, $parameters, $functionName )
	{
	$givenParameters = sizeof($parameters);

	if ( $givenParameters < $this->countRequiredParameters($definition, $reflectionParameters) )
	{
	throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_EXPECT_PARAMETER, $functionName, $definition->parameters[$givenParameters]));
	}

	if ( !$definition->variableArgumentList && $givenParameters > $this->countTotalParameters($definition, $reflectionParameters) )
	{
	throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_TOO_MANY_PARAMETERS, $functionName ) );
	}
	}

	/**
	* Orders the parameters.
	*
	* @param ReflectionParameters $reflectionParameters
	* @param array(ezcTemplateAstNode) $parameters
	* @param string $functionName
	* @return array(ezcTemplateAstNode)
	*/
	protected function orderParameters($reflectionParameters, $parameters, $functionName)
	{
	// First assign the named parameters, thereafter fill in the rest.
	$newParameters = array();

	// Process the named parameters.
	$maxNr = 0;

	// Named parameters.
	foreach ($parameters as $name => $value)
	{
	if (!is_int($name))
	{
	$found = false;
	$nr = 0;

	foreach ( $reflectionParameters as $rp)
	{
	if ( $rp->getName() === $name )
	{
	$found = true;
	break;
	}

	$nr++;
	}

	if ( !$found)
	{
	throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_NAMED_PARAMETER_NOT_FOUND, $name, $functionName ) );
	}

	$newParameters[$nr] = $value;
	$maxNr = max($nr, $maxNr);
	}
	}
	ksort($newParameters, SORT_NUMERIC);

	$i = 0;
	foreach ($parameters as $name => $value)
	{
	if (is_int($name))
	{
	while ( isset($newParameters[$i])) $i++;

	$newParameters[$i] = $value;
	}

	$i++;
	}

	// Search for 'holes'.
	for($i = 0; $i < $maxNr; $i++)
	{
	if ( !isset( $newParameters[$i]) )
	{
	if ( !$reflectionParameters[$i]->isDefaultValueAvailable() )
	{
	throw new ezcTemplateException( sprintf("Parameter %s is not given and has not a default value.", $i + 1) );
	}
	else
	{
	$newParameters[$i] = new ezcTemplateLiteralAstNode( $reflectionParameters[$i]->getDefaultValue() );
	}
	}
	}
	ksort($newParameters, SORT_NUMERIC);

	return $newParameters;
	}

	/**
	* Returns the reflection parameters.
	*
	* @param ezcTemplateCustomFunctionDefintion $definition
	* @return ReflectionParameters
	*/
	protected function getReflectionParameters( $definition )
	{
	if ( !isset($definition->class) \|\| $definition->class === false )
	{
	$rm = new ReflectionFunction( $definition->method );
	}
	else
	{
	$rc = new ReflectionClass( $definition->class );
	$rm = $rc->getMethod($definition->method);
	}

	return $rm->getParameters();
	}

	/**
	* Returns the corresponding AST tree to the function name $functionName and its parameters.
	*
	* The function name will, most likely, be translated from a Template function name to
	* the PHP function. The parameters are ordered, if needed.
	*
	* @param string $functionName
	* @param array(ezcTemplateAstNode) $parameters
	* @throws ezcTemplateException if the parameters are not valid (Too many, not enough parameters, etc).
	* @return ezcTemplateAstNode
	*/
	public function getAstTree( $functionName, $parameters )
	{
	// Try the built-in template functions.
	$class = $this->getClass( $functionName );

	if ( $class !== null )
	{
	$f = call_user_func( array( $class, "getFunctionSubstitution"), $functionName, $parameters );
	if ( $f !== null ) return $this->createAstNodes( $functionName, $f, $parameters );
	}

	// Try the custom template functions.
	$def = $this->getCustomFunction( $functionName );

	if ( $def !== false )
	{
	$reflectionParameters = $this->getReflectionParameters( $def );

	$a = new ezcTemplateFunctionCallAstNode( ( $def->class ? ( $def->class . "::" ) : "" ) . $def->method);
	$a->checkAndSetTypeHint();

	if ( isset($def->sendTemplateObject) && $def->sendTemplateObject )
	{
	array_shift($reflectionParameters);
	$a->appendParameter( new ezcTemplateVariableAstNode("this->template") );
	}

	$this->checkDefinition($def, $reflectionParameters);
	$this->checkGivenParameters($def, $reflectionParameters, $parameters, $functionName);

	$parameters = $this->orderParameters( $reflectionParameters, $parameters, $functionName);



	foreach ( $parameters as $p)
	{
	$a->appendParameter( $p );
	}

	return $a;
	}

	throw new ezcTemplateException( sprintf( ezcTemplateSourceToTstErrorMessages::MSG_UNKNOWN_FUNCTION, $functionName ) );
	}

	/**
	* Subclasses need to implement this method.
	*
	* @param string $functionName
	* @param array(ezcTemplateAstNode) $parameters
	* @throws ezcTemplateInternalException if the subclass does not implement this method.
	* @return array(mixed)
	*/
	public static function getFunctionSubstitution( $functionName, $parameters )
	{
	throw new ezcTemplateInternalException( "Subclasses need to implement the getFunctionSubstitution method." );
	}
	}
	?>