#!/usr/bin/env php
<?php

if (empty($argv[1])) { exit(1); }
$urlargs = $argv[1];

/*
*	Get the Bearer Token, this is an implementation of steps 1&2
*	from https://dev.twitter.com/docs/auth/application-only-auth
*/
function get_bearer_token(){
	require("secret.php");
	// Step 1
	// step 1.1 - url encode the consumer_key and consumer_secret in accordance with RFC 1738
	$encoded_consumer_key = urlencode($consumer_key);
	$encoded_consumer_secret = urlencode($consumer_secret);
	// step 1.2 - concatinate encoded consumer, a colon character and the encoded consumer secret
	$bearer_token = $encoded_consumer_key.':'.$encoded_consumer_secret;
	// step 1.3 - base64-encode bearer token
	$base64_encoded_bearer_token = base64_encode($bearer_token);
	// step 2
	$url = "https://api.twitter.com/oauth2/token"; // url to send data to for authentication
	$headers = array(
		"POST /oauth2/token HTTP/1.1",
		"Host: api.twitter.com",
		"User-Agent: jonhurlock Twitter Application-only OAuth App v.1",
		"Authorization: Basic ".$base64_encoded_bearer_token."",
		"Content-Type: application/x-www-form-urlencoded;charset=UTF-8",
		"Content-Length: 29"
	);

	$ch = curl_init();  // setup a curl
	curl_setopt($ch, CURLOPT_URL,$url);  // set url to send to
	curl_setopt($ch, CURLOPT_HTTPHEADER, $headers); // set custom headers
	curl_setopt($ch, CURLOPT_POST, 1); // send as post
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); // return output
	curl_setopt($ch, CURLOPT_POSTFIELDS, "grant_type=client_credentials"); // post body/fields to be sent
	$header = curl_setopt($ch, CURLOPT_HEADER, 1); // send custom headers
	$httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
	$retrievedhtml = curl_exec ($ch); // execute the curl
	curl_close($ch); // close the curl
	$output = explode("\n", $retrievedhtml);
	$bearer_token = '';
	foreach($output as $line)
	{
		if($line === false)
		{
			// there was no bearer token
		}else{
			$bearer_token = $line;
		}
	}
	$bearer_token = json_decode($bearer_token);
	return $bearer_token->{'access_token'};
}

/**
* Invalidates the Bearer Token
* Should the bearer token become compromised or need to be invalidated for any reason,
* call this method/function.
*/
function invalidate_bearer_token($bearer_token){
	$encoded_consumer_key = urlencode(CONSUMER_KEY);
	$encoded_consumer_secret = urlencode(CONSUMER_SECRET);
	$consumer_token = $encoded_consumer_key.':'.$encoded_consumer_secret;
	$base64_encoded_consumer_token = base64_encode($consumer_token);
	// step 2
	$url = "https://api.twitter.com/oauth2/invalidate_token"; // url to send data to for authentication
	$headers = array(
		"POST /oauth2/invalidate_token HTTP/1.1",
		"Host: api.twitter.com",
		"User-Agent: jonhurlock Twitter Application-only OAuth App v.1",
		"Authorization: Basic ".$base64_encoded_consumer_token."",
		"Accept: */*",
		"Content-Type: application/x-www-form-urlencoded",
		"Content-Length: ".(strlen($bearer_token)+13).""
	);

	$ch = curl_init();  // setup a curl
	curl_setopt($ch, CURLOPT_URL,$url);  // set url to send to
	curl_setopt($ch, CURLOPT_HTTPHEADER, $headers); // set custom headers
	curl_setopt($ch, CURLOPT_POST, 1); // send as post
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); // return output
	curl_setopt($ch, CURLOPT_POSTFIELDS, "access_token=".$bearer_token.""); // post body/fields to be sent
	$header = curl_setopt($ch, CURLOPT_HEADER, 1); // send custom headers
	$httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
	$retrievedhtml = curl_exec ($ch); // execute the curl
	curl_close($ch); // close the curl
	return $retrievedhtml;
}

function fetch($bearer_token, $query){
	$url = "https://api.twitter.com/1.1/statuses/user_timeline.json?";
	$headers = array(
		"GET /1.1/statuses/user_timeline.json?".$query." HTTP/1.1",
		"Host: api.twitter.com",
		"User-Agent: jonhurlock Twitter Application-only OAuth App v.1",
		"Authorization: Bearer ".$bearer_token."",
	);
	$ch = curl_init();  // setup a curl
	curl_setopt($ch, CURLOPT_URL, $url.$query);  // set url to send to
	curl_setopt($ch, CURLOPT_HTTPHEADER, $headers); // set custom headers
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); // return output
	curl_setopt($ch, CURLOPT_HEADER, true);
	$content = curl_exec($ch);
	list($header, $json) = explode("\r\n\r\n", $content, 2);
	curl_close($ch);

	file_put_contents('php://stderr', $header . "\n\n");

	// No results returned, Twitter API issue
	if (strlen($json) == 2) { exit(1); };

	return $json;

}

// $bearer_token = get_bearer_token(); // bearer token seems to last
require("secret.php");
echo "bearer token: " . $bearer_token . "\n";
print fetch($bearer_token, $urlargs); //  search for the work 'test'
//invalidate_bearer_token($bearer_token); // invalidate the token
?>