<?php
/*
 * Laconica - a distributed open-source microblogging tool
 * Copyright (C) 2008, Controlez-Vous, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

if (!defined('LACONICA')) { exit(1); }

function get_twitter_data($uri, $screen_name, $password) {

	$options = array(
			CURLOPT_USERPWD => sprintf("%s:%s", $screen_name, $password),
			CURLOPT_RETURNTRANSFER	=> true,
			CURLOPT_FAILONERROR		=> true,
			CURLOPT_HEADER			=> false,
			CURLOPT_FOLLOWLOCATION	=> true,
			// CURLOPT_USERAGENT		=> "identi.ca",
			CURLOPT_CONNECTTIMEOUT	=> 120,
			CURLOPT_TIMEOUT			=> 120
	);


	$ch = curl_init($uri);
    curl_setopt_array($ch, $options);
    $data = curl_exec($ch);
    $errmsg = curl_error($ch);

	if ($errmsg) {
		common_debug("Twitter bridge - cURL error: $errmsg - trying to load: $uri with user $twit_user.",
			__FILE__);
	}

	curl_close($ch);

	return $data;
}

function twitter_user_info($screen_name, $password) {

	$uri = "http://twitter.com/users/show/$screen_name.json";
	$data = get_twitter_data($uri, $screen_name, $password);

	if (!$data) {
		return false;
	}

	$twit_user = json_decode($data);

	if (!$twit_user) {
		return false;
	}

	return $twit_user;
}

function update_twitter_user($fuser, $twitter_id, $screen_name) {

	$original = clone($fuser);
	$fuser->nickname = $screen_name;
	$fuser->uri = 'http://twitter.com/' . $screen_name;
	$result = $fuser->updateKeys($original);

	if (!$result) {
		common_log_db_error($fuser, 'UPDATE', __FILE__);
		return false;
	}

	return true;
}

function add_twitter_user($twitter_id, $screen_name) {

	// Otherwise, create a new Twitter user
	$fuser = DB_DataObject::factory('foreign_user');

	$fuser->nickname = $screen_name;
	$fuser->uri = 'http://twitter.com/' . $screen_name;
	$fuser->id = $twitter_id;
	$fuser->service = 1; // Twitter
	$fuser->created = common_sql_now();
	$result = $fuser->insert();

	if (!$result) {
		common_debug("Twitter bridge - failed to add new Twitter user: $twitter_id - $screen_name.");
		common_log_db_error($fuser, 'INSERT', __FILE__);
		return false;
	}

	common_debug("Twitter bridge - Added new Twitter user: $screen_name ($twitter_id).");

	return true;
}

// Creates or Updates a Twitter user
function save_twitter_user($twitter_id, $screen_name) {

	// Check to see whether the Twitter user is already in the system,
	// and update its screen name and uri if so.
	$fuser = Foreign_user::getForeignUser($twitter_id, 1);

	if ($fuser) {

		// Only update if Twitter screen name has changed
		if ($fuser->nickname != $screen_name) {

			common_debug('Twitter bridge - Updated nickname (and URI) for Twitter user ' .
				"$fuser->id to $screen_name, was $fuser->nickname");

			return update_twitter_user($fuser, $twitter_id, $screen_name);
		}

	} else {
		return add_twitter_user($twitter_id, $screen_name);
	}

	return true;
}

function retreive_twitter_friends($twitter_id, $screen_name, $password) {

	$uri = "http://twitter.com/statuses/friends/$twitter_id.json?page=";
	$twitter_user = twitter_user_info($screen_name, $password);

	// Calculate how many pages to get...
	$pages = ceil($twitter_user->friends_count / 100);

	if ($pages == 0) {
		common_debug("Twitter bridge - Twitter user $screen_name has no friends! Lame.");
	}

	$friends = array();

	for ($i = 1; $i <= $pages; $i++) {

		$data = get_twitter_data($uri . $i, $screen_name, $password);

		if (!$data) {
			return NULL;
		}

		$more_friends = json_decode($data);

		if (!$more_friends) {
			return NULL;
		}

 		$friends = array_merge($friends, $more_friends);
	}

	return $friends;
}

function save_twitter_friends($user, $twitter_id, $screen_name, $password) {

	$friends = retreive_twitter_friends($twitter_id, $screen_name, $password);

	if (is_null($friends)) {
		common_debug("Twitter bridge - Couldn't get friends data from Twitter.");
		return false;
	}

    foreach ($friends as $friend) {

		$friend_name = $friend->screen_name;
		$friend_id = $friend->id;

		// Update or create the Foreign_user record
		if (!save_twitter_user($friend_id, $friend_name)) {
			return false;
		}

		// Check to see if there's a related local user
		$flink = Foreign_link::getByForeignID($friend_id, 1);

		if ($flink) {

			// Get associated user and subscribe her
			$friend_user = User::staticGet('id', $flink->user_id);
			subs_subscribe_to($user, $friend_user);
			common_debug("Twitter bridge - subscribed $friend_user->nickname to $user->nickname.");
		}
	}

	return true;
}