Wordpress twitter feed with cache template fragment

Wordpress - twitter feed with cache

<?php
	// source: http://spaceninja.com/2009/07/twitter-php-caching/
	//
	// define $twitterUsername and $twitterTweets in functions.php
	//
	global $twitterUsername, $twitterTweets;

	define("SECOND", 1);
	define("MINUTE", 60 * SECOND);
	define("HOUR", 60 * MINUTE);
	define("DAY", 24 * HOUR);
	define("MONTH", 30 * DAY);

	function relativeTime($time) {
	    $delta = strtotime('+2 hours') - $time;
	    if ($delta < 2 * MINUTE) {
	        return "1 min ago";
	    }
	    if ($delta < 45 * MINUTE) {
	        return floor($delta / MINUTE) . " mins ago";
	    }
	    if ($delta < 90 * MINUTE) {
	        return "1 hour ago";
	    }
	    if ($delta < 24 * HOUR) {
	        return floor($delta / HOUR) . " hours ago";
	    }
	    if ($delta < 48 * HOUR) {
	        return "Yesterday";
	    }
	    if ($delta < 30 * DAY) {
	        return floor($delta / DAY) . " days ago";
	    }
	    if ($delta < 12 * MONTH) {
	        $months = floor($delta / DAY / 30);
	        return $months <= 1 ? "1 month ago" : $months . " months ago";
	    } else {
	        $years = floor($delta / DAY / 365);
	        return $years <= 1 ? "1 year ago" : $years . " years ago";
	    }
	}

	function parse_cache_feed($usernames, $limit) {
	    $username_for_feed = str_replace(" ", "+OR+from%3A", $usernames);
	    $feed = "http://search.twitter.com/search.atom?q=from%3A" . $username_for_feed . "&rpp=" . $limit;
	    $usernames_for_file = str_replace(" ", "-", $usernames);
	    $cache_file = get_template_directory() . '/' . $usernames_for_file . '-twitter-cache';
	    $last = filemtime($cache_file);
	    $now = time();
	    $interval = 600; // ten minutes
	    // check the cache file
	    if ( !$last || (( $now - $last ) > $interval) ) {
	        // cache file doesn't exist, or is old, so refresh it
	        $cache_rss = file_get_contents($feed);
	        if (!$cache_rss) {
	            // we didn't get anything back from twitter
	            echo "<!-- ERROR: Twitter feed was blank! Using cache file. -->";
	        } else {
	            // we got good results from twitter
	            echo "<!-- SUCCESS: Twitter feed used to update cache file -->";
	            $cache_static = fopen($cache_file, 'wb');
	            fwrite($cache_static, serialize($cache_rss));
	            fclose($cache_static);
	        }
	        // read from the cache file
	        $rss = @unserialize(file_get_contents($cache_file));
	    }
	    else {
	        // cache file is fresh enough, so read from it
	        echo "<!-- SUCCESS: Cache file was recent enough to read from -->";
	        $rss = @unserialize(file_get_contents($cache_file));
	    }
	    // clean up and output the twitter feed
	    $feed = str_replace("&amp;", "&", $rss);
	    $feed = str_replace("&lt;", "<", $feed);
	    $feed = str_replace("&gt;", ">", $feed);
	    $clean = explode("<entry>", $feed);
	    $clean = str_replace("&quot;", "\"", $clean);
	    $clean = str_replace("&apos;", "'", $clean);
	    $amount = count($clean) - 1;
	    if ($amount) { // are there any tweets?
	        for ($i = 1; $i <= $amount; $i++) {
	            $entry_close = explode("</entry>", $clean[$i]);
	            $clean_content_1 = explode("<content type=\"html\">", $entry_close[0]);
	            $clean_content = explode("</content>", $clean_content_1[1]);
	            $clean_name_2 = explode("<name>", $entry_close[0]);
	            $clean_name_1 = explode("(", $clean_name_2[1]);
	            $clean_name = explode(")</name>", $clean_name_1[1]);
	            $clean_user = explode(" (", $clean_name_2[1]);
	            $clean_lower_user = strtolower($clean_user[0]);
	            $clean_uri_1 = explode("<uri>", $entry_close[0]);
	            $clean_uri = explode("</uri>", $clean_uri_1[1]);
	            $clean_time_1 = explode("<published>", $entry_close[0]);
	            $clean_time = explode("</published>", $clean_time_1[1]);
	            $unix_time = strtotime($clean_time[0]);
	            $pretty_time = relativeTime($unix_time);
	            ?>
	            <!-- format markup however required -->
	            <p class="content">
	                <?php echo $clean_content[0]; ?>
	            </p>
	            <p class="time">
	            	<a href="http://twitter.com/<?php echo $username_for_feed ?>" target="_blank">
	                    <?php echo $pretty_time; ?>
	                </a>
	            </p>
	            <?php
	        }
	    }
	}
	parse_cache_feed($twitterUsername, $twitterTweets);
?>