<?php

/*

 * This file is part of Twig.

 *

 * (c) 2009 Fabien Potencier

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

/**

 * Stores the Twig configuration.

 *

 * @package twig

 * @author  Fabien Potencier <fabien@symfony.com>

 */

class Twig_Environment

{

    const VERSION = '1.1.2';

    protected $charset;

    protected $loader;

    protected $debug;

    protected $autoReload;

    protected $cache;

    protected $lexer;

    protected $parser;

    protected $compiler;

    protected $baseTemplateClass;

    protected $extensions;

    protected $parsers;

    protected $visitors;

    protected $filters;

    protected $tests;

    protected $functions;

    protected $globals;

    protected $runtimeInitialized;

    protected $loadedTemplates;

    protected $strictVariables;

    protected $unaryOperators;

    protected $binaryOperators;

    protected $templateClassPrefix = '__TwigTemplate_';

    protected $functionCallbacks;

    protected $filterCallbacks;

    /**

     * Constructor.

     *

     * Available options:

     *

     *  * debug: When set to `true`, the generated templates have a __toString()

     *           method that you can use to display the generated nodes (default to

     *           false).

     *

     *  * charset: The charset used by the templates (default to utf-8).

     *

     *  * base_template_class: The base template class to use for generated

     *                         templates (default to Twig_Template).

     *

     *  * cache: An absolute path where to store the compiled templates, or

     *           false to disable compilation cache (default)

     *

     *  * auto_reload: Whether to reload the template is the original source changed.

     *                 If you don't provide the auto_reload option, it will be

     *                 determined automatically base on the debug value.

     *

     *  * strict_variables: Whether to ignore invalid variables in templates

     *                      (default to false).

     *

     *  * autoescape: Whether to enable auto-escaping (default to true);

     *

     *  * optimizations: A flag that indicates which optimizations to apply

     *                   (default to -1 which means that all optimizations are enabled;

     *                   set it to 0 to disable)

     *

     * @param Twig_LoaderInterface   $loader  A Twig_LoaderInterface instance

     * @param array                  $options An array of options

     */

    public function __construct(Twig_LoaderInterface $loader = null, $options = array())

    {

        if (null !== $loader) {

            $this->setLoader($loader);

        }

        $options = array_merge(array(

            'debug'               => false,

            'charset'             => 'UTF-8',

            'base_template_class' => 'Twig_Template',

            'strict_variables'    => false,

            'autoescape'          => true,

            'cache'               => false,

            'auto_reload'         => null,

            'optimizations'       => -1,

        ), $options);

        $this->debug              = (bool) $options['debug'];

        $this->charset            = $options['charset'];

        $this->baseTemplateClass  = $options['base_template_class'];

        $this->autoReload         = null === $options['auto_reload'] ? $this->debug : (bool) $options['auto_reload'];

        $this->extensions         = array(

            'core'      => new Twig_Extension_Core(),

            'escaper'   => new Twig_Extension_Escaper((bool) $options['autoescape']),

            'optimizer' => new Twig_Extension_Optimizer($options['optimizations']),

        );

        $this->strictVariables    = (bool) $options['strict_variables'];

        $this->runtimeInitialized = false;

        $this->setCache($options['cache']);

        $this->functionCallbacks = array();

        $this->filterCallbacks = array();

    }

    /**

     * Gets the base template class for compiled templates.

     *

     * @return string The base template class name

     */

    public function getBaseTemplateClass()

    {

        return $this->baseTemplateClass;

    }

    /**

     * Sets the base template class for compiled templates.

     *

     * @param string $class The base template class name

     */

    public function setBaseTemplateClass($class)

    {

        $this->baseTemplateClass = $class;

    }

    /**

     * Enables debugging mode.

     */

    public function enableDebug()

    {

        $this->debug = true;

    }

    /**

     * Disables debugging mode.

     */

    public function disableDebug()

    {

        $this->debug = false;

    }

    /**

     * Checks if debug mode is enabled.

     *

     * @return Boolean true if debug mode is enabled, false otherwise

     */

    public function isDebug()

    {

        return $this->debug;

    }

    /**

     * Enables the auto_reload option.

     */

    public function enableAutoReload()

    {

        $this->autoReload = true;

    }

    /**

     * Disables the auto_reload option.

     */

    public function disableAutoReload()

    {

        $this->autoReload = false;

    }

    /**

     * Checks if the auto_reload option is enabled.

     *

     * @return Boolean true if auto_reload is enabled, false otherwise

     */

    public function isAutoReload()

    {

        return $this->autoReload;

    }

    /**

     * Enables the strict_variables option.

     */

    public function enableStrictVariables()

    {

        $this->strictVariables = true;

    }

    /**

     * Disables the strict_variables option.

     */

    public function disableStrictVariables()

    {

        $this->strictVariables = false;

    }

    /**

     * Checks if the strict_variables option is enabled.

     *

     * @return Boolean true if strict_variables is enabled, false otherwise

     */

    public function isStrictVariables()

    {

        return $this->strictVariables;

    }

    /**

     * Gets the cache directory or false if cache is disabled.

     *

     * @return string|false

     */

    public function getCache()

    {

        return $this->cache;

    }

     /**

      * Sets the cache directory or false if cache is disabled.

      *

      * @param string|false $cache The absolute path to the compiled templates,

      *                            or false to disable cache

      */

    public function setCache($cache)

    {

        $this->cache = $cache ? $cache : false;

    }

    /**

     * Gets the cache filename for a given template.

     *

     * @param string $name The template name

     *

     * @return string The cache file name

     */

    public function getCacheFilename($name)

    {

        if (false === $this->cache) {

            return false;

        }

        $class = substr($this->getTemplateClass($name), strlen($this->templateClassPrefix));

        return $this->getCache().'/'.substr($class, 0, 2).'/'.substr($class, 2, 2).'/'.substr($class, 4).'.php';

    }

    /**

     * Gets the template class associated with the given string.

     *

     * @param string $name The name for which to calculate the template class name

     *

     * @return string The template class name

     */

    public function getTemplateClass($name)

    {

        return $this->templateClassPrefix.md5($this->loader->getCacheKey($name));

    }

    /**

     * Gets the template class prefix.

     *

     * @return string The template class prefix

     */

    public function getTemplateClassPrefix()

    {

        return $this->templateClassPrefix;

    }

    /**

     * Renders a template.

     *

     * @param string $name    The template name

     * @param array  $context An array of parameters to pass to the template

     *

     * @return string The rendered template

     */

    public function render($name, array $context = array())

    {

        return $this->loadTemplate($name)->render($context);

    }

    /**

     * Loads a template by name.

     *

     * @param  string  $name  The template name

     *

     * @return Twig_TemplateInterface A template instance representing the given template name

     */

    public function loadTemplate($name)

    {

        $cls = $this->getTemplateClass($name);

        if (isset($this->loadedTemplates[$cls])) {

            return $this->loadedTemplates[$cls];

        }

        if (!class_exists($cls, false)) {

            if (false === $cache = $this->getCacheFilename($name)) {

                eval('?>'.$this->compileSource($this->loader->getSource($name), $name));

            } else {

                if (!file_exists($cache) || ($this->isAutoReload() && !$this->loader->isFresh($name, filemtime($cache)))) {

                    $this->writeCacheFile($cache, $this->compileSource($this->loader->getSource($name), $name));

                }

                require_once $cache;

            }

        }

        if (!$this->runtimeInitialized) {

            $this->initRuntime();

        }

        return $this->loadedTemplates[$cls] = new $cls($this);

    }

    /**

     * Clears the internal template cache.

     */

    public function clearTemplateCache()

    {

        $this->loadedTemplates = array();

    }

    /**

     * Clears the template cache files on the filesystem.

     */

    public function clearCacheFiles()

    {

        if (false === $this->cache) {

            return;

        }

        foreach (new RecursiveIteratorIterator(new RecursiveDirectoryIterator($this->cache), RecursiveIteratorIterator::LEAVES_ONLY) as $file) {

            if ($file->isFile()) {

                @unlink($file->getPathname());

            }

        }

    }

    /**

     * Gets the Lexer instance.

     *

     * @return Twig_LexerInterface A Twig_LexerInterface instance

     */

    public function getLexer()

    {

        if (null === $this->lexer) {

            $this->lexer = new Twig_Lexer($this);

        }

        return $this->lexer;

    }

    /**

     * Sets the Lexer instance.

     *

     * @param Twig_LexerInterface A Twig_LexerInterface instance

     */

    public function setLexer(Twig_LexerInterface $lexer)

    {

        $this->lexer = $lexer;

    }

    /**

     * Tokenizes a source code.

     *

     * @param string $source The template source code

     * @param string $name   The template name

     *

     * @return Twig_TokenStream A Twig_TokenStream instance

     */

    public function tokenize($source, $name = null)

    {

        return $this->getLexer()->tokenize($source, $name);

    }

    /**

     * Gets the Parser instance.

     *

     * @return Twig_ParserInterface A Twig_ParserInterface instance

     */

    public function getParser()

    {

        if (null === $this->parser) {

            $this->parser = new Twig_Parser($this);

        }

        return $this->parser;

    }

    /**

     * Sets the Parser instance.

     *

     * @param Twig_ParserInterface A Twig_ParserInterface instance

     */

    public function setParser(Twig_ParserInterface $parser)

    {

        $this->parser = $parser;

    }

    /**

     * Parses a token stream.

     *

     * @param Twig_TokenStream $tokens A Twig_TokenStream instance

     *

     * @return Twig_Node_Module A Node tree

     */

    public function parse(Twig_TokenStream $tokens)

    {

        return $this->getParser()->parse($tokens);

    }

    /**

     * Gets the Compiler instance.

     *

     * @return Twig_CompilerInterface A Twig_CompilerInterface instance

     */

    public function getCompiler()

    {

        if (null === $this->compiler) {

            $this->compiler = new Twig_Compiler($this);

        }

        return $this->compiler;

    }

    /**

     * Sets the Compiler instance.

     *

     * @param Twig_CompilerInterface $compiler A Twig_CompilerInterface instance

     */

    public function setCompiler(Twig_CompilerInterface $compiler)

    {

        $this->compiler = $compiler;

    }

    /**

     * Compiles a Node.

     *

     * @param Twig_NodeInterface $node A Twig_NodeInterface instance

     *

     * @return string The compiled PHP source code

     */

    public function compile(Twig_NodeInterface $node)

    {

        return $this->getCompiler()->compile($node)->getSource();

    }