<?php
/**
 * StatusNet - the distributed open-source microblogging tool
 * Copyright (C) 2010, StatusNet, Inc.
 *
 * Send and receive notices using an IRC network
 *
 * PHP version 5
 *
 * 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/>.
 *
 * @category  IM
 * @package   StatusNet
 * @author    Luke Fitzgerald <lw.fitzgerald@googlemail.com>
 * @copyright 2010 StatusNet, Inc.
 * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
 * @link      http://status.net/
 */

if (!defined('STATUSNET')) {
    // This check helps protect against security problems;
    // your code file can't be executed directly from the web.
    exit(1);
}

// We bundle the Phergie library...
set_include_path(get_include_path() . PATH_SEPARATOR . dirname(__FILE__) . '/extlib/phergie');

/**
 * Plugin for IRC
 *
 * @category  Plugin
 * @package   StatusNet
 * @author    Luke Fitzgerald <lw.fitzgerald@googlemail.com>
 * @copyright 2010 StatusNet, Inc.
 * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
 * @link      http://status.net/
 */
class IrcPlugin extends ImPlugin {
    public $host =  null;
    public $port = null;
    public $username = null;
    public $realname = null;
    public $nick = null;
    public $password = null;
    public $nickservidentifyregexp = null;
    public $nickservpassword = null;
    public $channels = null;
    public $transporttype = null;
    public $encoding = null;
    public $pinginterval = null;

    public $regcheck = null;
    public $unregregexp = null;
    public $regregexp = null;

    public $transport = 'irc';
    protected $whiteList;
    protected $fake_irc;

    /**
     * Get the internationalized/translated display name of this IM service
     *
     * @return string Name of service
     */
    public function getDisplayName() {
        // TRANS: Service name for IRC.
        return _m('IRC');
    }

    /**
     * Normalize a screenname for comparison
     *
     * @param string $screenname Screenname to normalize
     * @return string An equivalent screenname in normalized form
     */
    public function normalize($screenname) {
        $screenname = str_replace(" ","", $screenname);
        return strtolower($screenname);
    }

    /**
     * Get the screenname of the daemon that sends and receives messages
     *
     * @return string Screenname
     */
    public function daemonScreenname() {
        return $this->nick;
    }

    /**
     * Validate (ensure the validity of) a screenname
     *
     * @param string $screenname Screenname to validate
     * @return boolean true if screenname is valid
     */
    public function validate($screenname) {
        if (preg_match('/\A[a-z0-9\-_]{1,1000}\z/i', $screenname)) {
            return true;
        } else {
            return false;
        }
    }

    /**
     * Load related modules when needed
     *
     * @param string $cls Name of the class to be loaded
     * @return boolean hook value; true means continue processing, false means stop.
     */
    public function onAutoload($cls) {
        // in the beginning of this file, we have added an include path
        if (substr($cls, 0, 7) == 'Phergie') {
            include_once str_replace('_', DIRECTORY_SEPARATOR, $cls) . '.php';
            return false;
        }

        return parent::onAutoload($cls);
    }

    /*
     * Start manager on daemon start
     *
     * @param array &$versions Array to insert manager into
     * @return boolean
     */
    public function onStartImDaemonIoManagers(&$classes) {
        parent::onStartImDaemonIoManagers($classes);
        $classes[] = new IrcManager($this); // handles sending/receiving
        return true;
    }

    /**
    * Ensure the database table is present
    *
    */
    public function onCheckSchema() {
        $schema = Schema::get();

        // For storing messages while sessions become ready
        $schema->ensureTable('irc_waiting_message', Irc_waiting_message::schemaDef());
        return true;
    }

    /**
    * Get a microid URI for the given screenname
    *
    * @param string $screenname Screenname
    * @return string microid URI
    */
    public function microiduri($screenname) {
        return 'irc:' . $screenname;
    }

    /**
     * Send a message to a given screenname
     *
     * @param string $screenname Screenname to send to
     * @param string $body Text to send
     * @return boolean true on success
     */
    public function sendMessage($screenname, $body) {
        $lines = explode("\n", $body);
        foreach ($lines as $line) {
            $this->fake_irc->doPrivmsg($screenname, $line);
            $this->enqueueOutgoingRaw(array('type' => 'message', 'prioritise' => 0, 'data' => $this->fake_irc->would_be_sent));
        }
        return true;
    }

    /**
     * Accept a queued input message.
     *
     * @return boolean true if processing completed, false if message should be reprocessed
     */
    public function receiveRawMessage($data) {
        if (strpos($data['source'], '#') === 0) {
            $message = $data['message'];
            $parts = explode(' ', $message, 2);
            $command = $parts[0];
            if (in_array($command, $this->whiteList)) {
                $this->handle_channel_incoming($data['sender'], $data['source'], $message);
            } else {
                $this->handleIncoming($data['sender'], $message);
            }
        } else {
            $this->handleIncoming($data['sender'], $data['message']);
        }
        return true;
    }

    /**
     * Helper for handling incoming messages from a channel requiring response
     * to the channel instead of via PM
     *
     * @param string $nick Screenname the message was sent from
     * @param string $channel Channel the message originated from
     * @param string $message Message text
     * @param boolean true on success
     */
    protected function handle_channel_incoming($nick, $channel, $notice_text) {
        $user = $this->getUser($nick);
        // For common_current_user to work
        global $_cur;
        $_cur = $user;

        if (!$user) {
            $this->sendFromSite($nick, 'Unknown user; go to ' .
                             common_local_url('imsettings') .
                             ' to add your address to your account');
            common_log(LOG_WARNING, 'Message from unknown user ' . $nick);
            return;
        }
        if ($this->handle_channel_command($user, $channel, $notice_text)) {
            common_log(LOG_INFO, "Command message by $nick handled.");
            return;
        } else if ($this->isAutoreply($notice_text)) {
            common_log(LOG_INFO, 'Ignoring auto reply from ' . $nick);
            return;
        } else if ($this->isOtr($notice_text)) {
            common_log(LOG_INFO, 'Ignoring OTR from ' . $nick);
            return;
        } else {
            common_log(LOG_INFO, 'Posting a notice from ' . $user->nickname);
            $this->addNotice($nick, $user, $notice_text);
        }

        $user->free();
        unset($user);
        unset($_cur);
        unset($message);
    }

    /**
     * Attempt to handle a message from a channel as a command
     *
     * @param User $user User the message is from
     * @param string $channel Channel the message originated from
     * @param string $body Message text
     * @return boolean true if the message was a command and was executed, false if it was not a command
     */
    protected function handle_channel_command($user, $channel, $body) {
        $inter = new CommandInterpreter();
        $cmd = $inter->handle_command($user, $body);
        if ($cmd) {
            $chan = new ChannelResponseChannel($this, $channel);
            $cmd->execute($chan);
            return true;
        } else {
            return false;
        }
    }

    /**
     * Send a confirmation code to a user
     *
     * @param string $screenname screenname sending to
     * @param string $code the confirmation code
     * @param User $user user sending to
     * @return boolean success value
     */
    public function sendConfirmationCode($screenname, $code, $user, $checked = false) {
        // TRANS: Body text for e-mail confirmation message for IRC.
        // TRANS: %1$s is a user nickname, %2$s is the StatusNet sitename,
        // TRANS: %3$s is the plugin display name ("IRC"), %4$s is the confirm address URL.
        $body = sprintf(_m('User "%1$s" on %2$s has said that your %3$s screenname belongs to them. ' .
          'If that\'s true, you can confirm by clicking on this URL: ' .
          '%4$s' .
          ' . (If you cannot click it, copy-and-paste it into the ' .
          'address bar of your browser). If that user is not you, ' .
          'or if you did not request this confirmation, just ignore this message.'),
          $user->nickname, common_config('site', 'name'), $this->getDisplayName(), common_local_url('confirmaddress', array('code' => $code)));

        if ($this->regcheck && !$checked) {
            return $this->checked_sendConfirmationCode($screenname, $code, $user);
        } else {
            return $this->sendMessage($screenname, $body);
        }
    }

    /**
    * Only sends the confirmation message if the nick is
    * registered
    *
    * @param string $screenname Screenname sending to
    * @param string $code The confirmation code
    * @param User $user User sending to
    * @return boolean true on succes
    */
    public function checked_sendConfirmationCode($screenname, $code, $user) {
        $this->fake_irc->doPrivmsg('NickServ', 'INFO '.$screenname);
        $this->enqueueOutgoingRaw(
            array(
                'type' => 'nickcheck',
                'prioritise' => 1,
                'data' => $this->fake_irc->would_be_sent,
                'nickdata' =>
                    array(
                        'screenname' => $screenname,
                        'code' => $code,
                        'user' => $user
                    )
            )
        );
        return true;
    }

    /**
    * Initialize plugin
    *
    * @return boolean
    */
    public function initialize() {
        if (!isset($this->host)) {
            // TRANS: Exception thrown when initialising the IRC plugin fails because of an incorrect configuration.
            throw new Exception(_m('You must specify a host.'));
        }
        if (!isset($this->username)) {
            // TRANS: Exception thrown when initialising the IRC plugin fails because of an incorrect configuration.
            throw new Exception(_m('You must specify a username.'));
        }
        if (!isset($this->realname)) {
            // TRANS: Exception thrown when initialising the IRC plugin fails because of an incorrect configuration.
            throw new Exception(_m('You must specify a "real name".'));
        }
        if (!isset($this->nick)) {
            // TRANS: Exception thrown when initialising the IRC plugin fails because of an incorrect configuration.
            throw new Exception(_m('You must specify a nickname.'));
        }

        if (!isset($this->port)) {
            $this->port = 6667;
        }
        if (!isset($this->transporttype)) {
            $this->transporttype = 'tcp';
        }
        if (!isset($this->encoding)) {
            $this->encoding = 'UTF-8';
        }
        if (!isset($this->pinginterval)) {
            $this->pinginterval = 120;
        }

        if (!isset($this->regcheck)) {
            $this->regcheck = true;
        }

        $this->fake_irc = new FakeIrc;

        /*
         * Commands allowed to return output to a channel
         */
        $this->whiteList = array('stats', 'last', 'get');

        return true;
    }

    /**
     * Get plugin information
     *
     * @param array $versions Array to insert information into
     * @return void
     */
    public function onPluginVersion(&$versions) {
        $versions[] = array('name' => 'IRC',
                            'version' => GNUSOCIAL_VERSION,
                            'author' => 'Luke Fitzgerald',
                            'homepage' => 'http://status.net/wiki/Plugin:IRC',
                            'rawdescription' =>
                            // TRANS: Plugin description.
                            _m('The IRC plugin allows users to send and receive notices over an IRC network.'));
        return true;
    }
}