<?php
/**
 *  @copyright 2017  Cloudways  https://www.cloudways.com
 *
 *  Original development of this plugin by JoomUnited https://www.joomunited.com/
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
defined('ABSPATH') || die('No direct script access allowed!');

class Breeze_CDN_Rewrite {
    private $blog_url = null;
    private $cdn_url = null;
    private $dirs = array();
    private $excludes = array();
    private $relative = false;

    public function __construct(&$option){
        //storage option
        $this->blog_url = get_option('home');
        $this->cdn_url = $option['cdn-url'];
        $this->dirs = $option['cdn-content'];
        $this->excludes = $option['cdn-exclude-content'];
        $this->relative = $option['cdn-relative-path'];

        $this->hardcoded_exceptions_to_ignore();
    }

	/**
	 * Handles extra exceptions which need to be excluded
	 * and instead use local URL instead of CDN.
	 *
	 * @since 1.1.3
	 */
	private function hardcoded_exceptions_to_ignore() {
		if ( ! array( $this->excludes ) || empty( $this->excludes ) ) {
			$this->excludes = array();
		}
		$this->excludes [] = 'download_file';
		// Allow users to use filter and add exceptions from CDN url.
		$this->excludes = apply_filters( 'breeze_cdn_exclude_paths', $this->excludes );
	}

    /*
     * Replace cdn on html raw
     */
    public function rewrite($content){

        $blog_url = quotemeta($this->blog_url);

        // get dir scope in regex format
        $dirs = $this->get_dir_scope();

        // regex rule start
        $regex_rule = '#(?<=[(\"\'])';

	    // create blog url without http or https
	    $parseurl = parse_url($this->blog_url);
	    $scheme = 'http:';
	    if(!empty($parseurl['scheme'])){
		    $scheme = $parseurl['scheme'].':';
	    }
	    $blog_url_short = str_replace($scheme, '',$this->blog_url);

	    // check if relative paths
	    if ($this->relative) {
		    $regex_rule .= '(?:'.$blog_url.'|'.$blog_url_short.')?';
	    } else {
		    $regex_rule .= '('.$blog_url.'|'.$blog_url_short.')';
	    }

        // regex rule end
        $regex_rule .= '/(?:((?:'.$dirs.')[^\"\')]+)|([^/\"\']+\.[^/\"\')]+))(?=[\"\')])#';

        // call the cdn rewriter callback
        $new_content = preg_replace_callback($regex_rule, array(&$this, 'replace_cdn_url'), $content);

        return $new_content;
    }

    /**
     * get directory scope
     */

    protected function get_dir_scope() {
        // default
        if (empty($this->dirs) || count($this->dirs) < 1) {
            return 'wp\-content|wp\-includes';
        }

        return implode('|', array_map('quotemeta', array_map('trim', $this->dirs)));
    }

    /*
     * Replace cdn url to root url
     */
    protected function replace_cdn_url($match){
        //return file type or directories excluded
        if($this->excludes_check($match[0])){
            return $match[0];
        }

        $parseUrl = parse_url($this->blog_url);
	    $scheme = 'http://';
        if(isset($parseUrl['scheme'])){
            $scheme = $parseUrl['scheme'].'://';
        }
        $host = $parseUrl['host'];
        //get domain
	    $domain = '//'.$host;

        // check if not a relative path
        if (!$this->relative || strstr($match[0], $this->blog_url)) {
	        $domain = $scheme.$host;
        }

	    return str_replace($domain, $this->cdn_url, $match[0]);

    }
    /*
     * Check excludes assets
     */
    protected function excludes_check($dir){
        if(!empty($this->excludes)){
            foreach ($this->excludes as $exclude){
                if(stristr($dir, $exclude) != false){
                    return true;
                }
            }
        }
        return false;
    }
}