/libs/Nette/Templating/Template.php

<?php



/**

 * This file is part of the Nette Framework (http://nette.org)

 *

 * Copyright (c) 2004, 2011 David Grudl (http://davidgrudl.com)

 *

 * For the full copyright and license information, please view

 * the file license.txt that was distributed with this source code.

 */



namespace Nette\Templating;



use Nette,

	Nette\Caching;







/**

 * Template.

 *

 * @author     David Grudl

 */

class Template extends Nette\Object implements ITemplate

{

	/** @var bool */

	public $warnOnUndefined = TRUE;



	/** @var array of function(Template $sender); Occurs before a template is compiled - implement to customize the filters */

	public $onPrepareFilters = array();



	/** @var string */

	private $source;



	/** @var array */

	private $params = array();



	/** @var array compile-time filters */

	private $filters = array();



	/** @var array run-time helpers */

	private $helpers = array();



	/** @var array */

	private $helperLoaders = array();



	/** @var Nette\Caching\IStorage */

	private $cacheStorage;







	/**

	 * Sets template source code.

	 * @param  string

	 * @return Template  provides a fluent interface

	 */

	public function setSource($source)

	{

		$this->source = $source;

		return $this;

	}







	/**

	 * Returns template source code.

	 * @return source

	 */

	public function getSource()

	{

		return $this->source;

	}







	/********************* rendering ****************d*g**/







	/**

	 * Renders template to output.

	 * @return void

	 */

	public function render()

	{

		$cache = new Caching\Cache($storage = $this->getCacheStorage(), 'Nette.Template');

		$cached = $compiled = $cache->load($this->source);



		if ($compiled === NULL) {

			$compiled = $this->compile();

			$cache->save($this->source, $compiled, array(Caching\Cache::CONSTS => 'Nette\Framework::REVISION'));

			$cached = $cache->load($this->source);

		}



		if ($cached !== NULL && $storage instanceof Caching\Storages\PhpFileStorage) {

			Nette\Utils\LimitedScope::load($cached['file'], $this->getParams());

		} else {

			Nette\Utils\LimitedScope::evaluate($compiled, $this->getParams());

		}

	}







	/**

	 * Renders template to file.

	 * @param  string

	 * @return void

	 */

	public function save($file)

	{

		if (file_put_contents($file, $this->__toString(TRUE)) === FALSE) {

			throw new Nette\IOException("Unable to save file '$file'.");

		}

	}







	/**

	 * Renders template to string.

	 * @param  bool  can throw exceptions? (hidden parameter)

	 * @return string

	 */

	public function __toString()

	{

		$args = func_get_args();

		ob_start();

		try {

			$this->render();

			return ob_get_clean();



		} catch (\Exception $e) {

			ob_end_clean();

			if ($args && $args[0]) {

				throw $e;

			} else {

				Nette\Diagnostics\Debugger::toStringException($e);

			}

		}

	}







	/**

	 * Applies filters on template content.

	 * @return string

	 */

	public function compile()

	{

		if (!$this->filters) {

			$this->onPrepareFilters($this);

		}



		$code = $this->getSource();

		foreach ($this->filters as $filter) {

			$code = self::extractPhp($code, $blocks);

			$code = $filter($code);

			$code = strtr($code, $blocks); // put PHP code back

		}



		return self::optimizePhp($code);

	}







	/********************* template filters & helpers ****************d*g**/







	/**

	 * Registers callback as template compile-time filter.

	 * @param  callback

	 * @return void

	 */

	public function registerFilter($callback)

	{

		$callback = callback($callback);

		if (in_array($callback, $this->filters)) {

			throw new Nette\InvalidStateException("Filter '$callback' was registered twice.");

		}

		$this->filters[] = $callback;

	}







	/**

	 * Returns all registered compile-time filters.

	 * @return array

	 */

	final public function getFilters()

	{

		return $this->filters;

	}







	/**

	 * Registers callback as template run-time helper.

	 * @param  string

	 * @param  callback

	 * @return void

	 */

	public function registerHelper($name, $callback)

	{

		$this->helpers[strtolower($name)] = callback($callback);

	}







	/**

	 * Registers callback as template run-time helpers loader.

	 * @param  callback

	 * @return void

	 */

	public function registerHelperLoader($callback)

	{

		$this->helperLoaders[] = callback($callback);

	}







	/**

	 * Returns all registered run-time helpers.

	 * @return array

	 */

	final public function getHelpers()

	{

		return $this->helpers;

	}







	/**

	 * Call a template run-time helper. Do not call directly.

	 * @param  string  helper name

	 * @param  array   arguments

	 * @return mixed

	 */

	public function __call($name, $args)

	{

		$lname = strtolower($name);

		if (!isset($this->helpers[$lname])) {

			foreach ($this->helperLoaders as $loader) {

				$helper = $loader($lname);

				if ($helper) {

					$this->registerHelper($lname, $helper);

					return $this->helpers[$lname]->invokeArgs($args);

				}

			}

			return parent::__call($name, $args);

		}



		return $this->helpers[$lname]->invokeArgs($args);

	}







	/**

	 * Sets translate adapter.

	 * @param  Nette\Localization\ITranslator

	 * @return Template  provides a fluent interface

	 */

	public function setTranslator(Nette\Localization\ITranslator $translator = NULL)

	{

		$this->registerHelper('translate', $translator === NULL ? NULL : array($translator, 'translate'));

		return $this;

	}







	/********************* template parameters ****************d*g**/







	/**

	 * Adds new template parameter.

	 * @param  string  name

	 * @param  mixed   value

	 * @return void

	 */

	public function add($name, $value)

	{

		if (array_key_exists($name, $this->params)) {

			throw new Nette\InvalidStateException("The variable '$name' already exists.");

		}



		$this->params[$name] = $value;

	}







	/**

	 * Sets all parameters.

	 * @param  array

	 * @return Template  provides a fluent interface

	 */

	public function setParams(array $params)

	{

		$this->params = $params + $this->params;

		return $this;

	}







	/**

	 * Returns array of all parameters.

	 * @return array

	 */

	public function getParams()

	{

		$this->params['template'] = $this;

		return $this->params;

	}







	/**

	 * Sets a template parameter. Do not call directly.

	 * @param  string  name

	 * @param  mixed   value

	 * @return void

	 */

	public function __set($name, $value)

	{

		$this->params[$name] = $value;

	}







	/**

	 * Returns a template parameter. Do not call directly.

	 * @param  string  name

	 * @return mixed  value

	 */

	public function &__get($name)

	{

		if ($this->warnOnUndefined && !array_key_exists($name, $this->params)) {

			trigger_error("The variable '$name' does not exist in template.", E_USER_NOTICE);

		}



		return $this->params[$name];

	}







	/**

	 * Determines whether parameter is defined. Do not call directly.

	 * @param  string    name

	 * @return bool

	 */

	public function __isset($name)

	{

		return isset($this->params[$name]);

	}







	/**

	 * Removes a template parameter. Do not call directly.

	 * @param  string    name

	 * @return void

	 */

	public function __unset($name)

	{

		unset($this->params[$name]);

	}







	/********************* caching ****************d*g**/







	/**

	 * Set cache storage.

	 * @param  Nette\Caching\Cache

	 * @return void

	 */

	public function setCacheStorage(Caching\IStorage $storage)

	{

		$this->cacheStorage = $storage;

	}







	/**

	 * @return Nette\Caching\IStorage

	 */

	public function getCacheStorage()

	{

		if ($this->cacheStorage === NULL) {

			return new Caching\Storages\DevNullStorage;

		}

		return $this->cacheStorage;

	}







	/********************* tools ****************d*g**/







	/**

	 * Extracts all blocks of PHP code.

	 * @param  string

	 * @param  array

	 * @return string

	 */

	private static function extractPhp($source, & $blocks)

	{

		$res = '';

		$blocks = array();

		$tokens = token_get_all($source);

		foreach ($tokens as $n => $token) {

			if (is_array($token)) {

				if ($token[0] === T_INLINE_HTML || $token[0] === T_CLOSE_TAG) {

					$res .= $token[1];

					continue;



				} elseif ($token[0] === T_OPEN_TAG && $token[1] === '<?' && isset($tokens[$n+1][1]) && $tokens[$n+1][1] === 'xml') {

					$php = & $res;

					$token[1] = '<<?php ?>?';



				} elseif ($token[0] === T_OPEN_TAG || $token[0] === T_OPEN_TAG_WITH_ECHO) {

					$res .= $id = "<?php \x01@php:p" . count($blocks) . "@\x02";

					$php = & $blocks[$id];

				}

				$php .= $token[1];



			} else {

				$php .= $token;

			}

		}

		return $res;

	}







	/**

	 * Removes unnecessary blocks of PHP code.

	 * @param  string

	 * @return string

	 */

	public static function optimizePhp($source, $lineLength = 80, $existenceOfThisParameterSolvesDamnBugInPHP535 = NULL)

	{

		$res = $php = '';

		$lastChar = ';';

		$tokens = new \ArrayIterator(token_get_all($source));

		foreach ($tokens as $key => $token) {

			if (is_array($token)) {

				if ($token[0] === T_INLINE_HTML) {

					$lastChar = '';

					$res .= $token[1];



				} elseif ($token[0] === T_CLOSE_TAG) {

					$next = isset($tokens[$key + 1]) ? $tokens[$key + 1] : NULL;

					if (substr($res, -1) !== '<' && preg_match('#^<\?php\s*$#', $php)) {

						$php = ''; // removes empty (?php ?), but retains ((?php ?)?php



					} elseif (is_array($next) && $next[0] === T_OPEN_TAG) { // remove ?)(?php

						if (!strspn($lastChar, ';{}:/')) {

							$php .= $lastChar = ';';

						}

						if (substr($next[1], -1) === "\n") {

							$php .= "\n";

						}

						$tokens->next();



					} elseif ($next) {

						$res .= preg_replace('#;?(\s)*$#', '$1', $php) . $token[1]; // remove last semicolon before ?)

						if (strlen($res) - strrpos($res, "\n") > $lineLength

							&& (!is_array($next) || strpos($next[1], "\n") === FALSE)

						) {

							$res .= "\n";

						}

						$php = '';



					} else { // remove last ?)

						if (!strspn($lastChar, '};')) {

							$php .= ';';

						}

					}



				} elseif ($token[0] === T_ELSE || $token[0] === T_ELSEIF) {

					if ($tokens[$key + 1] === ':' && $lastChar === '}') {

						$php .= ';'; // semicolon needed in if(): ... if() ... else:

					}

					$lastChar = '';

					$php .= $token[1];



				} else {

					if (!in_array($token[0], array(T_WHITESPACE, T_COMMENT, T_DOC_COMMENT, T_OPEN_TAG))) {

						$lastChar = '';

					}

					$php .= $token[1];

				}

			} else {

				$php .= $lastChar = $token;

			}

		}

		return $res . $php;

	}



}