<?php
/*
	Copyright 2016 Tygre <tygre@chingu.asia>

	This file is an extension to Triki Wiki.

	This extension 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 3 of the License, or
	(at your option) any later version.

	This extension 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 extension. If not, see <http://www.gnu.org/licenses/>.
*/

require("default-db.php");

function isNodeInCache($title) {
    global $nodedir;

    // blacklist the title
    if (blacklistTitle($title)) {
		return false;
	}

	$wikiFile  = $nodedir.$title.".wiki";
	$cacheFile = $nodedir.$title.".cache";
	if (file_exists($wikiFile) && 
		file_exists($cacheFile) && 
		filemtime($wikiFile) < filemtime($cacheFile)) {

		return TRUE;
	}
	
	return FALSE;
}

function saveNodeContentsInCache($title, $node) {
    global $nodedir;

    // open the file
    $file = fopen($nodedir.$title.".cache", "w");
    if ($file === false) return false;

    // and lock it
    flock($file, LOCK_EX);

	// write content
	fwrite($file, $node);

    // finish
    flock($file, LOCK_UN);
}

function getNodeContentsFromCache($title) {
    global $nodedir;

    if (!isNodeInCache($title)) return false;

    // open the file
    $file = fopen($nodedir.$title.".cache", "r");
    if ($file === false) return false;

    // and lock it
    flock($file, LOCK_SH);

    // read content
    $html = fread($file, 65535);
    $html = rtrim($html);

    // finish
    flock($file, LOCK_UN);
    fclose($file);

    return $html;
}
?>