Cache.php

<?php

namespace plugins\riCache;

/**
 * @package Pages
 * @copyright Copyright 2003-2006 Zen Cart Development Team
 * @copyright Portions Copyright 2003 osCommerce
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 * @version $Id: cache.php 274 2009-11-20 17:13:45Z yellow1912 $
 */
class Cache
{

    /**
     * @var
     */
    protected $cache;

    /**
     * @var
     */
    protected $path;

    /**
     * @var
     */
    protected $status;

    /**
     * @var array
     */
    protected $blocks = array();

    /**
     * @var
     */
    protected $settings;

    /**
     * @var
     */
    protected $cacheDir;

    /**
     * @param $settings
     */

    /**
     * @var
     */
    protected $utilityFile;

    public function __construct($settings, $utilityFile, $cacheDir)
    {
        $this->utilityFile = $utilityFile;
        $this->status = $settings->get('ricache.status');
        $this->cacheDir = $cacheDir;
    }

    public function getPath()
    {
        return $this->path;
    }

    public function write($file, $content, $use_subfolder = false)
    {

        if (!$this->status) return false;

        $cache_folder = dirname($file);

        // if this dir does not exist, assuming we need to append absolute cache path
        if (!is_dir($cache_folder)) {
            $cache_folder = $this->cacheDir . '/' . $cache_folder;
        }

        $name = basename($file);

        $this->cache[$cache_folder][$name] = $content;

        $cache_folder = $this->calculatePath($name, $cache_folder, $use_subfolder);

        $cache_file = "$cache_folder/$name";

        $written = 0;
        if ($fp = @fopen($cache_file, 'wb')) {

            // lock file for writing
            if (flock($fp, LOCK_EX)) {
                $written = fwrite($fp, $content);
            }
            fclose($fp);

            // Set filemtime
            touch($cache_file, time() + 3600);

            //@chmod($cache_file, 0777);
        }

        return $written !== false && $written > 0 ? $cache_file : false;
    }

    public function read($file, $use_subfolder = false)
    {

        if (!$this->status) return false;

        $cache_folder = dirname($file);

        // if this dir does not exist, assuming we need to append absolute cache path
        if (!is_dir($cache_folder))
            $cache_folder = $this->cacheDir . '/' . $cache_folder;

        $name = basename($file);

        if (isset($this->cache[$cache_folder][$name]))
            return $this->cache[$cache_folder][$name];

        $cache_folder = $this->calculatePath($name, $cache_folder, $use_subfolder);

        $cache_file = "$cache_folder/$name";

        $read = @file_get_contents($cache_file);

        return $read ? $read : false;
    }

    public function remove($name = '', $cache_folder, $DeleteMe = false)
    {
        if (empty($name)) {

            if (!is_dir($cache_folder)) {
                $cache_folder = $this->cacheDir . '/' . $cache_folder;
            }

            return $this->utilityFile->sureRemoveDir($cache_folder, $DeleteMe);
        } else {
            return @unlink($cache_folder . $name);
        }
    }

    public function startBlock($id, $change_on_page = false, $depend_on = "", $post_safe = true)
    {
        if (!$this->status || (!$post_safe && $_SERVER["REQUEST_METHOD"] == 'POST') || isset($_GET[zen_session_id()]))
            return false;

        if ($change_on_page) $id .= getenv('REQUEST_URI');

        $id = md5($id . $depend_on);

        if (($content = $this->read($this->cacheDir . '/' . $id, 'content')) !== false) {
            echo $content;
            return true;
        }

        $this->blocks[] = $id;

        ob_start();
        return false;
    }

    public function startPage($depend_on = "", $post_safe = false)
    {
        if (!$this->status || ($post_safe && $_SERVER["REQUEST_METHOD"] == 'POST') || isset($_GET[zen_session_id()]))
            return false;

        global $current_page_base;

        $id = md5($current_page_base . getenv('REQUEST_URI') . $depend_on);

        if (($content = $this->read($this->cacheDir . '/' . $id)) !== false) {
            echo $content;
            return true;
        }

        $this->blocks[] = $id;

        ob_start();
        return false;
    }

    public function end()
    {
        if (!$this->status)
            return false;

        $id = array_pop($this->blocks);
        $content = ob_get_clean();
        $this->write($this->cacheDir . '/' . $id, $content);

        echo $content;
    }

    public function exists($file, $use_subfolder = false)
    {
        $name = basename($file);
        $cache_folder = $this->calculatePath($name, dirname($file), $use_subfolder);
        return file_exists("$cache_folder/$name") ? "$cache_folder/$name" : false;
    }

    private function calculatePath($name, $cache_folder, $use_subfolder)
    {
        $cache_folder = "$cache_folder/";
        if ($use_subfolder) {
            $path = substr($name, 0, 4);
            $cache_folder .= chunk_split($path, 1, '/');
        }

        $cache_folder = rtrim($cache_folder, '/');

        riMkDir($cache_folder);

        return $cache_folder;
    }
}