<?php
/*
Twitterbox Intermediary Thing v0.2
Ordinal Malaprop
Last updated 2007-02-28

This script sits on a server somewhere and sends and receives data from Twitter. It is meant to be able to talk to an LSL script in a way that it can easily deal with.
*/

// Basic function to send a request to Twitter
function twitter_send($file, $user, $pass, $data) {
	$c = curl_init();
	curl_setopt($c, CURLOPT_URL, "http://twitter.com/statuses/$file.json");
	curl_setopt($c, CURLOPT_PATH, TRUE);
	curl_setopt($c, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
	curl_setopt($c, CURLOPT_USERPWD, "$user:$pass");
	curl_setopt($c, CURLOPT_POSTFIELDS, $data);
	curl_setopt($c, CURLOPT_RETURNTRANSFER, TRUE);
	curl_setopt($c, CURLOPT_HEADER, FALSE);
	curl_setopt($c, CURLOPT_USERAGENT, "TwitterBox 0.2");
	$response = @curl_exec($c);
	if (chop($response)) {
		$json = json_decode($response, TRUE);
		curl_close($c);
//		print_r($json);
		return $json;
	}
	else die("Could not contact Twitter!");
}

// Get a tinyurl for something
function get_tinyurl($bigurl)
{
	$c = curl_init();
	curl_setopt($c, CURLOPT_URL, "http://tinyurl.com/api-create.php?url=$bigurl");
	curl_setopt($c, CURLOPT_RETURNTRANSFER, TRUE);
	curl_setopt($c, CURLOPT_HEADER, FALSE);
	$tinyurl = curl_exec($c);
	curl_close($c);
	return $tinyurl;
}

// Main code

header("Content-type: text/plain");

// Read POST input
$post = file('php://input');

// If there isn't anything in the POST, don't do anything
if (!$post) {
	die("go away");
}

// Read in the information that was sent
$user = urldecode(chop($post[0]));
$pass = urldecode(chop($post[1]));
$action = urldecode(chop($post[2]));
$status = urldecode(chop($post[3]));
// location to add slurl for, in the form simname/x/y/z/
$location = urldecode(chop($post[4])); 

// Allow for slight clock irregularities
$now = time() - 5;

ob_flush();
flush();

// Now process the action requested
// All of these request feedback from Twitter in JSON format, which is parsed by the above function.
if ($action == "update") {
	// The update procedure
	// If there's a SLURL keyword in there somewhere...
	if (strpos($status, "SLURL") !== FALSE && $location) {
		// Compose the slurl itself from the position passed on automatically
		// SLurl page strips out all HTML in the msg - didn't know that...
		$slurl = "http://slurl.com/secondlife/". str_replace(" ", "%20", $location). "?x=200&y=120&title=". urlencode(gmdate("j M y @ H:i", time() - 28800). " SLT"). "&msg=". rawurlencode(htmlentities($status)). "&img=http%3A//ordinalmalaprop.com/twitter/twitterbox-credit.jpg";
		// Get a tinyurl for this slurl - Twitter doesn't seem to reliably compose tinyurls
		$tiny_slurl = get_tinyurl($slurl);
		// Replace all instances of the SLURL keyword in the tweet with the tinyslurl
		$status = str_replace("SLURL", $tiny_slurl, $status);
		ob_flush();
		flush();
	}
	$json = twitter_send('update', $user, $pass, "status=".  rawurlencode($status));
	// Check the time that the last update was posted at
	$created = strtotime($json["created_at"]);
	// If the time is before now, that means it's failed!
	if ($created < $now) {
		die("Failed to post!");
	}
	// Otherwise say "ok" and coincidentally update the screen name and ID
	else {
		echo "OK,". $json["user"]["id"]. ",". $json["user"]["screen_name"]. ",posted";
	}
}
else if ($action == "get id" && ($json = twitter_send('update', $user, $pass, ""))) {
	// To just update the screen name and ID, send a blank update which will not be displayed
	// and read in the information.
	echo "OK,". $json["user"]["id"]. ",". $json["user"]["screen_name"];
}
else if ($action == "check" && ($json = twitter_send('friends_timeline', $user, $pass, ""))) {
	// Check recent tweets
	// Go through them and compile a list of the last few, up to an appropriate size limit to send back to LSL
	// 1500 bytes should work - longer than that and the header gets in the way
	// LSL doesn't like receiving any real quantity of data
	$length = 0;
	$entry = "";
	$f = 0;
	$max = count($json);
	do {
		$length += strlen($entry);
		if ($entry != "") $tweets[] = $entry;
		// Format for each tweet:
		// <user's screen name>
		// <text with relative created at time>
		// <UNIX time of creation, to see if it's new>
		$entry = $json[$f]["user"]["screen_name"]. "\n". $json[$f]["text"]. " (". $json[$f]["relative_created_at"]. ")\n". strtotime($json[$f]["created_at"]);
		ob_flush();
		flush();
	} while (++$f < $max && $length + strlen($entry) < 1500);
	// Put them in chronological order
	$tweets = array_reverse($tweets);
	// and output
	echo "OK\n". implode("\n", $tweets);
}
else echo "what?";

?>