<?php
/*
Plugin Name: nginx fastcgi Cache Purge
Plugin URI: http://mattgadient.com/flushing-the-nginx-fastcgi-cache-via-php-and-or-wordpress/
Description: WARNING: verify cache location in nginx-fastcgi-cache-purge.php BEFORE activating. Purges cache automatically after posting/editing, and manually via settings page. 
Version: 0.0.2
Author: Matt Gadient
Author URI: http://mattgadient.com/

Copyright (C)2013 Matt Gadient

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.
*/ 

if (!defined('ABSPATH')) {
    die();
}


//
// You MUST verify that the cache location below is correct before
// enabling the plugin, and change it if not.
//
// Also a good idea to ensure that permissions are correct.
//
// YOU HAVE BEEN WARNED!
//

$nginx_cache_location = "/var/cache/nginx/";

///var/cache/nginx/tpktrade

//ini_set( 'error_reporting', E_ALL );

if ( ! function_exists( 'plugin_log' ) ) {
  function plugin_log( $entry, $mode = 'a', $file = 'plugin' ) { 
    // Get WordPress uploads directory.
    $upload_dir = wp_upload_dir();
    $upload_dir = $upload_dir['basedir'];
    // If the entry is array, json_encode.
    if ( is_array( $entry ) ) { 
      $entry = json_encode( $entry ); 
    } 
    // Write the log file.
    $file  = $upload_dir . '/' . $file . '.log';
    $file  = fopen( $file, $mode );
    $bytes = fwrite( $file, current_time( 'mysql' ) . "::" . $entry . "\n" ); 
    fclose( $file ); 
    return $bytes;
  }
}






//
// The actual filters that will be checked against to auto-purge the entire cache.
// If you do not want the plugin to auto-purge, comment them out.
//

add_filter ('switch_theme',  'deleteCache', 100);
add_filter ('publish_post',  'deleteCache', 100);
add_filter ('edit_post',  'deleteCache', 100);
add_filter ('delete_post',  'deleteCache', 100);
add_filter ('save_post',  'deleteCache', 100);
add_filter ('add_category',  'deleteCache', 100);
add_filter ('delete_category',  'deleteCache', 100);


//add_action( 'save_post', 'cs_twitter_save_meta', 100, 3 );
function cs_twitter_save_meta( $post_id, $post, $update  ) {

	global $nginx_cache_location;

// // Check the logged in user has permission to edit this post
// if ( ! current_user_can( 'manage_options' ) ) {
// return $post_id;
// }
// // Only want to set if this is a new post!
// if ( $update ){
// return;
// }

// // If this is just a revision, don't send the email.
if ( wp_is_post_revision( $post_id ) ) {
return;
}
// API request (not in gutenberg)
//if (REST_REQUEST) return;

// autosave
if (wp_is_post_autosave($post_id)) return;

// if ( get_post_type( $post_id ) !== 'event' ) return;

// // Only set for post_type = post!
// if ( 'post' !== $post->post_type ) {
// return;
// }


	$url = parse_url( get_the_permalink($post_id) );
	 //plugin_log($url);


			if ($url) {

				$scheme = $url['scheme'];
				$host = $url['host'];
				$requesturi = $url['path'];
				$hash = md5($scheme.'GET'.$host.$requesturi);
				$file = $nginx_cache_location . substr($hash, -1) . '/' . substr($hash,-3,2) . '/' . $hash;
				
				plugin_log($file);



if (file_exists($file)) {

//plugin_log(var_dump(unlink($file)));

$file_success = unlink($file);

plugin_log( $file_success ? "The file was deleted" : "The file was not deleted" );



	//$file_success = unlink($file);

	

	// if ($file_success) {
	// 				plugin_log('Successfully removed');
	// 				//echo ('<p style="color:green;font-size:14px;">Successfully removed ' 
	// 				//. $_POST['purge_single']
	// 				//. ' from the cache!</p>');
	// 			} else {
	// 				plugin_log('Unable to remove cached file!');
	// 				//echo ('<p style="color:orange;font-size:14px;">Unable to remove cached file!<br />
	// 				//It is possible that nginx cleared it just before you did, although if you always&nbsp;
	// 				//get this message, chances are that something is not configured correctly.</p>');
	// 			}

}

//plugin_log('$file_success - '.$file_success);

				//$file_success = unlink($nginx_cache_location . substr($hash, -1) . '/' . substr($hash,-3,2) . '/' . $hash);

				//plugin_log($nginx_cache_location . substr($hash, -1) . '/' . substr($hash,-3,2) . '/' . $hash);

				// if ($file_success) {
				// 	plugin_log('Successfully removed');
				// 	//echo ('<p style="color:green;font-size:14px;">Successfully removed ' 
				// 	//. $_POST['purge_single']
				// 	//. ' from the cache!</p>');
				// } else {
				// 	plugin_log('Unable to remove cached file!');
				// 	//echo ('<p style="color:orange;font-size:14px;">Unable to remove cached file!<br />
				// 	//It is possible that nginx cleared it just before you did, although if you always&nbsp;
				// 	//get this message, chances are that something is not configured correctly.</p>');
				// }
			}

}
//
// The function that deletes the entire cache when called.
//

function deleteCache() {

	echo '';
	global $nginx_cache_location;
	if ((is_dir($nginx_cache_location)) && (is_writable($nginx_cache_location))) {
		array_map('unlink', glob($nginx_cache_location . "*/*/*"));
		array_map('rmdir', glob($nginx_cache_location . "*/*"));
		array_map('rmdir', glob($nginx_cache_location . "*"));
	} else {
		echo ('<p style="color:red;font-size:14px;">Warning! ' . $nginx_cache_location 
			. ' was not found, or not accessible! Doing nothing.</p>');
	}
	
}


//
// Creates the menu and adds the option page to it.
//
			
add_action('admin_menu', 'add_plugin_nginx_cache_menu');
function add_plugin_nginx_cache_menu() {
    add_options_page('nginx cache settings', 'nginx Cache Purge', 'manage_options', 'nginx_cache_purge', 'nginx_cache_page');
}

//
// The actual option page. Contains most of the logic (a bit messy).
//

function nginx_cache_page() {
	global $wpdb;
	global $nginx_cache_location;

	// If manually purging all is selected, this happens.
	if (isset($_POST['purge'])) {
    	echo ('<p style="color:green;font-size:14px;">Attempted to purge all cached files from ' . $nginx_cache_location 
    		. '...<br />check file counts below to see if it was successful (should show 0).</p>');
		deleteCache();
	}
	
	// If manually purging a single post/page, this happens.
	if (isset($_POST['purge_single']))
	{
		$url = parse_url($_POST['purge_single']);
			if (!$url) {
				echo '<p style="color:red;font-size:14px;">There was a problem parsing the URL, so we are 
						<b>not</b> attempting to clear it. Possible misconfiguration.</p>';
			} else {
				$scheme = $url['scheme'];
				$host = $url['host'];
				$requesturi = $url['path'];
				$hash = md5($scheme.'GET'.$host.$requesturi);
				$file_success = unlink($nginx_cache_location . substr($hash, -1) . '/' . substr($hash,-3,2) . '/' . $hash);
				if ($file_success) {
					echo ('<p style="color:green;font-size:14px;">Successfully removed ' 
					. $_POST['purge_single']
					. ' from the cache!</p>');
				} else {
					echo ('<p style="color:orange;font-size:14px;">Unable to remove cached file!<br />
					It is possible that nginx cleared it just before you did, although if you always&nbsp;
					get this message, chances are that something is not configured correctly.</p>');
				}
			}
	}


	//
	// This collects a list of page/post url's from the wordpress database, and
	// checks for the existance of each in the cache. We end up with:
	// 	-a total number of pages/posts that are cached. 
	// 	-a string we can print later listing them (with a purge button on each)
	//	
	
	$url_list = "";
	$counted_urls = 0;
	$postID = $wpdb->get_col("
	SELECT ID FROM $wpdb->posts
	WHERE ((post_type = 'post') OR (post_type = 'page'))
	AND (post_status = 'publish')
	");

	echo '<ul id="post_links">';
	foreach($postID as $post_link) {
		$url = parse_url(get_permalink($post_link));
		if(!$url) {
			echo '<p style="color:red;font-size:14px;"><b>WARNING: Unable to determine the URLs from 
				the wordpress database. Recommend you do NOT continue.</b></p>';
		} else {
			$scheme = $url['scheme'];
			$host = $url['host'];
			$requesturi = $url['path'];
			$hash = md5($scheme.'GET'.$host.$requesturi);

			if (file_exists($nginx_cache_location . substr($hash, -1) . '/' . substr($hash,-3,2) . '/' . $hash)) {
				$counted_urls++;
				$url_list .= ('<li><button type="submit" name="purge_single" value="' 
					. get_permalink($post_link) 
					. '" ><i>(purge from cache)</i></button> <b>' 
					. get_the_title($post_link) . '</b> ' . get_permalink($post_link) 
					. '</li>');
			}
		}
	}	



//
// Finally, the main option page output.
//

?>

<p>The path currently hardwired into the plugin is <b><?php echo $nginx_cache_location ?></b>
  and it also assumes you have used <b>levels=1:2</b> <i>(suggest you verify both before using this plugin).</i></p>

<p>A quick check was done to see if <b><?php echo $nginx_cache_location; ?></b> existed and was writable, and...&nbsp;

<?php if ((is_dir($nginx_cache_location)) && (is_writable($nginx_cache_location))) {
	echo '<span style="color:green;">It appears to be writable!</span>';
	} else {
	echo '<span style="color:red;">It does not appear to be writable!!! You should deactivate the plugin immediately'
		. ' and verify that the value hardcoded in the plugin matches the setting in your nginx config!</span>';
	} 
?>
</p>

<p> </p>
<p>------------------------------</p>
<p> </p>

<p>Saving/editing a post, adding/deleting a category, approving comments, and changing the theme
should all automatically clear the entire cache unless the check above failed.</p>

<p> </p>
<p>------------------------------</p>
<p> </p>

<p style="font-size:14px;">Currently there appear to be <b><?php echo sizeof(glob($nginx_cache_location . "*/*/*")); ?></b> items cached by nginx in total.<br />
<b><?php echo $counted_urls; ?></b> were matched to your posts/pages, and are listed below.</p>

<form method="post" action="">
<?php wp_nonce_field(); ?>	
	<p class="submit">
    	<input class="button" type="submit" name="purge" value="Purge all items from cache" />
	</p>
<p>Clicking the button above will attempt to purge the cache of all files. You can selectively
target files below if you would prefer.</p>

<?php

echo $url_list;

} 
 
 ?>