<?php
/*
 *  OPEN POWER LIBS <http://www.invenzzia.org>
 *
 * This file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE. It is also available through
 * WWW at this URL: <http://www.invenzzia.org/license/new-bsd>
 *
 * Copyright (c) Invenzzia Group <http://www.invenzzia.org>
 * and other contributors. See website for details.
 *
 */

	class Opt_Instruction_If extends Opt_Compiler_Processor
	{
		protected $_name = 'if';
		protected $_cnt = 0;
	
		public function configure()
		{
			$this->_addInstructions(array('opt:if', 'opt:elseif', 'opt:else'));
			$this->_addAttributes(array('opt:if', 'opt:on'));
		} // end configure();
		
		public function processNode(Opt_Xml_Node $node)
		{
			$params = array(
				'test' => array(0 => self::REQUIRED, self::EXPRESSION)
			);
			
			switch($node->getName())
			{
				case 'if':
					$this->_extractAttributes($node, $params);
					$node->addAfter(Opt_Xml_Buffer::TAG_BEFORE, ' if('.$params['test'].'){ ');			
					$node->addBefore(Opt_Xml_Buffer::TAG_AFTER, ' } ');
					$node->sort(array('*' => 0, 'opt:elseif' => 1, 'opt:else' => 2));
					$this->_process($node);
					break;
				case 'elseif':
					if($node->getParent()->getName() == 'if')
					{
						$this->_extractAttributes($node, $params);
						$node->addBefore(Opt_Xml_Buffer::TAG_BEFORE, ' } elseif('.$params['test'].'){ ');
						$this->_process($node);
					}
					else
					{
						throw new Opt_InstructionInvalidParent_Exception($node->getXmlName(), 'opt:if');
					}
					break;
				case 'else':
					if($node->getParent()->getName() == 'if')
					{
						$node->addBefore(Opt_Xml_Buffer::TAG_BEFORE, '}else{ ');
						$this->_process($node);
					}
					else
					{
						throw new Opt_InstructionInvalidParent_Exception($node->getXmlName(), 'opt:if');
					}
					break;			
			}
		} // end processNode();
		
		public function processAttribute(Opt_Xml_Node $node, Opt_Xml_Attribute $attr)
		{
			switch($attr->getName())
			{
				case 'on':
					if(!$this->_compiler->isNamespace($node->getNamespace()))
					{
						$expr = $this->_compiler->compileExpression((string)$attr, false, Opt_Compiler_Class::ESCAPE_OFF);

						$node->addBefore(Opt_Xml_Buffer::TAG_OPENING_BEFORE, ' $_tag_'.$this->_cnt.' = false; if('.$expr[0].'){ $_tag_'.$this->_cnt.' = true; ');			
						$node->addAfter(Opt_Xml_Buffer::TAG_OPENING_AFTER, ' } ');
						$node->addBefore(Opt_Xml_Buffer::TAG_CLOSING_BEFORE, ' if($_tag_'.$this->_cnt.' === true){ ');			
						$node->addAfter(Opt_Xml_Buffer::TAG_CLOSING_AFTER, ' } ');
						$this->_cnt++;
						break;
					}
				case 'if':
					// opt:if added to an section must be handled differently.
					// Wait for the section processor and add the condition in the postprocessing.
					if($this->_compiler->isInstruction($node->getXmlName()) instanceof Opt_Instruction_BaseSection)
					{
						$attr->set('postprocess', true);
						return;
					}

					$expr = $this->_compiler->compileExpression((string)$attr, false, Opt_Compiler_Class::ESCAPE_OFF);

					$node->addBefore(Opt_Xml_Buffer::TAG_BEFORE, ' if('.$expr[0].'){ ');			
					$node->addAfter(Opt_Xml_Buffer::TAG_AFTER, ' } ');
			}
		} // end processAttribute();

		public function postprocessAttribute(Opt_Xml_Node $node, Opt_Xml_Attribute $attr)
		{
			$expr = $this->_compiler->compileExpression((string)$attr, false, Opt_Compiler_Class::ESCAPE_OFF);

			$node->addBefore(Opt_Xml_Buffer::TAG_BEFORE, ' if('.$expr[0].'){ ');
			$node->addAfter(Opt_Xml_Buffer::TAG_AFTER, ' } ');
		} // end postprocessAttribute();
	} // end Opt_Instruction_If;