<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * 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@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Cache

 * @subpackage Zend_Cache_Frontend

 * @copyright  Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id$

 */

/**

 * @see Zend_Cache_Core

 */

require_once 'Zend/Cache/Core.php';

/**

 * @package    Zend_Cache

 * @subpackage Zend_Cache_Frontend

 * @copyright  Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Cache_Frontend_Page extends Zend_Cache_Core

{

    /**

     * This frontend specific options

     *

     * ====> (boolean) http_conditional :

     * - if true, http conditional mode is on

     * WARNING : http_conditional OPTION IS NOT IMPLEMENTED FOR THE MOMENT (TODO)

     *

     * ====> (boolean) debug_header :

     * - if true, a debug text is added before each cached pages

     *

     * ====> (boolean) content_type_memorization :

     * - deprecated => use memorize_headers instead

     * - if the Content-Type header is sent after the cache was started, the

     *   corresponding value can be memorized and replayed when the cache is hit

     *   (if false (default), the frontend doesn't take care of Content-Type header)

     *

     * ====> (array) memorize_headers :

     * - an array of strings corresponding to some HTTP headers name. Listed headers

     *   will be stored with cache datas and "replayed" when the cache is hit

     *

     * ====> (array) default_options :

     * - an associative array of default options :

     *     - (boolean) cache : cache is on by default if true

     *     - (boolean) cacheWithXXXVariables  (XXXX = 'Get', 'Post', 'Session', 'Files' or 'Cookie') :

     *       if true,  cache is still on even if there are some variables in this superglobal array

     *       if false, cache is off if there are some variables in this superglobal array

     *     - (boolean) makeIdWithXXXVariables (XXXX = 'Get', 'Post', 'Session', 'Files' or 'Cookie') :

     *       if true, we have to use the content of this superglobal array to make a cache id

     *       if false, the cache id won't be dependent of the content of this superglobal array

     *     - (int) specific_lifetime : cache specific lifetime

     *                                (false => global lifetime is used, null => infinite lifetime,

     *                                 integer => this lifetime is used), this "lifetime" is probably only

     *                                usefull when used with "regexps" array

     *     - (array) tags : array of tags (strings)

     *     - (int) priority : integer between 0 (very low priority) and 10 (maximum priority) used by

     *                        some particular backends

     *

     * ====> (array) regexps :

     * - an associative array to set options only for some REQUEST_URI

     * - keys are (pcre) regexps

     * - values are associative array with specific options to set if the regexp matchs on $_SERVER['REQUEST_URI']

     *   (see default_options for the list of available options)

     * - if several regexps match the $_SERVER['REQUEST_URI'], only the last one will be used

     *

     * @var array options

     */

    protected $_specificOptions = array(

        'http_conditional' => false,

        'debug_header' => false,

        'content_type_memorization' => false,

        'memorize_headers' => array(),

        'default_options' => array(

            'cache_with_get_variables' => false,

            'cache_with_post_variables' => false,

            'cache_with_session_variables' => false,

            'cache_with_files_variables' => false,

            'cache_with_cookie_variables' => false,

            'make_id_with_get_variables' => true,

            'make_id_with_post_variables' => true,

            'make_id_with_session_variables' => true,

            'make_id_with_files_variables' => true,

            'make_id_with_cookie_variables' => true,

            'cache' => true,

            'specific_lifetime' => false,

            'tags' => array(),

            'priority' => null

        ),

        'regexps' => array()

    );

    /**

     * Internal array to store some options

     *

     * @var array associative array of options

     */

    protected $_activeOptions = array();

    /**

     * If true, the page won't be cached

     *

     * @var boolean

     */

    protected $_cancel = false;

    /**

     * Constructor

     *

     * @param  array   $options                Associative array of options

     * @param  boolean $doNotTestCacheValidity If set to true, the cache validity won't be tested

     * @throws Zend_Cache_Exception

     * @return void

     */

    public function __construct(array $options = array())

    {

        foreach ($options as $name => $value) {

            $name = strtolower($name);

            switch ($name) {

                case 'regexps':

                    $this->_setRegexps($value);

                    break;

                case 'default_options':

                    $this->_setDefaultOptions($value);

                    break;

                case 'content_type_memorization':

                    $this->_setContentTypeMemorization($value);

                    break;

                default:

                    $this->setOption($name, $value);

            }

        }

        if (isset($this->_specificOptions['http_conditional'])) {

            if ($this->_specificOptions['http_conditional']) {

                Zend_Cache::throwException('http_conditional is not implemented for the moment !');

            }

        }

        $this->setOption('automatic_serialization', true);

    }

    /**

     * Specific setter for the 'default_options' option (with some additional tests)

     *

     * @param  array $options Associative array

     * @throws Zend_Cache_Exception

     * @return void

     */

    protected function _setDefaultOptions($options)

    {

        if (!is_array($options)) {

            Zend_Cache::throwException('default_options must be an array !');

        }

        foreach ($options as $key=>$value) {

            if (!is_string($key)) {

                Zend_Cache::throwException("invalid option [$key] !");

            }

            $key = strtolower($key);

            if (isset($this->_specificOptions['default_options'][$key])) {

                $this->_specificOptions['default_options'][$key] = $value;

            }

        }

    }

    /**

     * Set the deprecated contentTypeMemorization option

     *

     * @param boolean $value value

     * @return void

     * @deprecated

     */

    protected function _setContentTypeMemorization($value)

    {

        $found = null;

        foreach ($this->_specificOptions['memorize_headers'] as $key => $value) {

            if (strtolower($value) == 'content-type') {

                $found = $key;

            }

        }

        if ($value) {

            if (!$found) {

                $this->_specificOptions['memorize_headers'][] = 'Content-Type';

            }

        } else {

            if ($found) {

                unset($this->_specificOptions['memorize_headers'][$found]);

            }

        }

    }

    /**

     * Specific setter for the 'regexps' option (with some additional tests)

     *

     * @param  array $options Associative array

     * @throws Zend_Cache_Exception

     * @return void

     */

    protected function _setRegexps($regexps)

    {

        if (!is_array($regexps)) {

            Zend_Cache::throwException('regexps option must be an array !');

        }

        foreach ($regexps as $regexp=>$conf) {

            if (!is_array($conf)) {

                Zend_Cache::throwException('regexps option must be an array of arrays !');

            }

            $validKeys = array_keys($this->_specificOptions['default_options']);

            foreach ($conf as $key=>$value) {

                if (!is_string($key)) {

                    Zend_Cache::throwException("unknown option [$key] !");

                }

                $key = strtolower($key);

                if (!in_array($key, $validKeys)) {

                    unset($regexps[$regexp][$key]);

                }

            }

        }

        $this->setOption('regexps', $regexps);

    }

    /**

     * Start the cache

     *

     * @param  string  $id       (optional) A cache id (if you set a value here, maybe you have to use Output frontend instead)

     * @param  boolean $doNotDie For unit testing only !

     * @return boolean True if the cache is hit (false else)

     */

    public function start($id = false, $doNotDie = false)

    {

        $this->_cancel = false;

        $lastMatchingRegexp = null;

        if (isset($_SERVER['REQUEST_URI'])) {

            foreach ($this->_specificOptions['regexps'] as $regexp => $conf) {

                if (preg_match("`$regexp`", $_SERVER['REQUEST_URI'])) {

                    $lastMatchingRegexp = $regexp;

                }

            }

        }

        $this->_activeOptions = $this->_specificOptions['default_options'];

        if ($lastMatchingRegexp !== null) {

            $conf = $this->_specificOptions['regexps'][$lastMatchingRegexp];

            foreach ($conf as $key=>$value) {

                $this->_activeOptions[$key] = $value;

            }

        }

        if (!($this->_activeOptions['cache'])) {

            return false;

        }

        if (!$id) {

            $id = $this->_makeId();

            if (!$id) {

                return false;

            }

        }

        $array = $this->load($id);

        if ($array !== false) {

            $data = $array['data'];

            $headers = $array['headers'];

            if (!headers_sent()) {

                foreach ($headers as $key=>$headerCouple) {

                    $name = $headerCouple[0];

                    $value = $headerCouple[1];

                    header("$name: $value");

                }

            }

            if ($this->_specificOptions['debug_header']) {

                echo 'DEBUG HEADER : This is a cached page !';

            }

            echo $data;

            if ($doNotDie) {

                return true;

            }

            die();

        }

        ob_start(array($this, '_flush'));

        ob_implicit_flush(false);

        return false;

    }

    /**

     * Cancel the current caching process

     */

    public function cancel()

    {

        $this->_cancel = true;

    }

    /**

     * callback for output buffering

     * (shouldn't really be called manually)

     *

     * @param  string $data Buffered output

     * @return string Data to send to browser

     */

    public function _flush($data)

    {

        if ($this->_cancel) {

            return $data;

        }

        $contentType = null;

        $storedHeaders = array();

        $headersList = headers_list();

        foreach($this->_specificOptions['memorize_headers'] as $key=>$headerName) {

            foreach ($headersList as $headerSent) {

                $tmp = explode(':', $headerSent);

                $headerSentName = trim(array_shift($tmp));

                if (strtolower($headerName) == strtolower($headerSentName)) {

                    $headerSentValue = trim(implode(':', $tmp));

                    $storedHeaders[] = array($headerSentName, $headerSentValue);

                }

            }

        }

        $array = array(

            'data' => $data,

            'headers' => $storedHeaders

        );

        $this->save($array, null, $this->_activeOptions['tags'], $this->_activeOptions['specific_lifetime'], $this->_activeOptions['priority']);

        return $data;

    }

    /**

     * Make an id depending on REQUEST_URI and superglobal arrays (depending on options)

     *

     * @return mixed|false a cache id (string), false if the cache should have not to be used

     */

    protected function _makeId()

    {

        $tmp = $_SERVER['REQUEST_URI'];

        $array = explode('?', $tmp, 2);

          $tmp = $array[0];

        foreach (array('Get', 'Post', 'Session', 'Files', 'Cookie') as $arrayName) {

            $tmp2 = $this->_makePartialId($arrayName, $this->_activeOptions['cache_with_' . strtolower($arrayName) . '_variables'], $this->_activeOptions['make_id_with_' . strtolower($arrayName) . '_variables']);

            if ($tmp2===false) {

                return false;

            }

            $tmp = $tmp . $tmp2;

        }

        return md5($tmp);

    }

    /**

     * Make a partial id depending on options

     *

     * @param  string $arrayName Superglobal array name

     * @param  bool   $bool1     If true, cache is still on even if there are some variables in the superglobal array

     * @param  bool   $bool2     If true, we have to use the content of the superglobal array to make a partial id

     * @return mixed|false Partial id (string) or false if the cache should have not to be used

     */

    protected function _makePartialId($arrayName, $bool1, $bool2)

    {

        switch ($arrayName) {

        case 'Get':

            $var = $_GET;

            break;

        case 'Post':

            $var = $_POST;

            break;

        case 'Session':

            if (isset($_SESSION)) {

                $var = $_SESSION;

            } else {

                $var = null;

            }

            break;

        case 'Cookie':

            if (isset($_COOKIE)) {

                $var = $_COOKIE;

            } else {

                $var = null;

            }

            break;

        case 'Files':

            $var = $_FILES;

            break;

        default:

            return false;

        }

        if ($bool1) {

            if ($bool2) {

                return serialize($var);

            }

            return '';

        }

        if (count($var) > 0) {

            return false;

        }

        return '';

    }

}