<?php
// This file is part of the Sloodle project (www.sloodle.org)

/**
* This file defines the Sloodle Distributor module.
*
* @package sloodle
* @copyright Copyright (c) 2008 Sloodle (various contributors)
* @license http://www.gnu.org/licenses/gpl-3.0.html GNU GPL v3
*
* @contributor Peter R. Bloomfield
*/

/** The Sloodle module base. */
require_once(SLOODLE_LIBROOT.'/modules/module_base.php');
/** General Sloodle functions. */
require_once(SLOODLE_LIBROOT.'/general.php');

/**
* The Sloodle Distributor module class.
* @package sloodle
*/
class SloodleModuleDistributor extends SloodleModule
{
// DATA //

    /**
    * Internal for Moodle only - course module instance.
    * Corresponds to one record from the Moodle 'course_modules' table.
    * @var object
    * @access private
    */
    var $cm = null;

    /**
    * Internal only - Sloodle module instance database object.
    * Corresponds to one record from the Moodle 'sloodle' table.
    * @var object
    * @access private
    */
    var $sloodle_module_instance = null;
    
    /**
    * Internal only - Sloodle Distributor instance database object.
    * Corresponds to one record from the Moodle 'sloodle_distributor' table.
    * @var object
    * @access private
    */
    var $sloodle_distributor_instance = null;
            
    
// FUNCTIONS //

    /**
    * Constructor
    */
    //function SloodleModuleDistributor(&$_session)
    function __construct(&$_session)
    {
        parent::__construct($_session);
    }
    

    /**
    * Loads data from the database.
    * Note: even if the function fails, it may still have overwritten some or all existing data in the object.
    * @param mixed $id The site-wide unique identifier for all modules. Type depends on VLE. On Moodle, it is an integer course module identifier ('id' field of 'course_modules' table)
    * @return bool True if successful, or false otherwise
    */
    function load($id)
    {
        // Make sure the ID is valid
        if (!is_int($id) || $id <= 0) return false;
        
        // Fetch the course module data
        if (!($this->cm = get_coursemodule_from_id('sloodle', $id))) return false;
        // Load from the primary table: Sloodle instance
        if (!($this->sloodle_module_instance = sloodle_get_record('sloodle', 'id', $this->cm->instance))) return false;
        // Check that it is the correct type
        if ($this->sloodle_module_instance->type != SLOODLE_TYPE_DISTRIB) return false;
        
        // Load from the secondary table: Distributor instance
        if (!($this->sloodle_distributor_instance = sloodle_get_record('sloodle_distributor', 'sloodleid', $this->cm->instance))) return false;
        
        return true;
    }
    
    
    /**
    * Gets a list of all objects for this Distributor.
    * @return array An array of strings, each string containing the name of an object in this Distributor.
    */
    function get_objects()
    {
        // Get all distributor record entries for this distributor, sorted alphabetically
        $recs = sloodle_get_records('sloodle_distributor_entry', 'distributorid', $this->sloodle_distributor_instance->id, 'name');
        if (!$recs) return array();
        // Convert it to an array of strings
        $entries = array();
        foreach ($recs as $r) {
            $entries[] = $recs->name;
        }
        
        return $entries;
    }
    
    
    /**
    * Sets the list of objects in this Distributor
    * @param array $objects An array of strings, each string containing the name of an object in the Distributor.
    * @return bool True if successful, or false if not
    */
    function set_objects($objects)
    {
        // Delete all existing records for this Distributor
        sloodle_delete_records('sloodle_distributor_entry', 'distributorid', $this->sloodle_distributor_instance->id);
        
        // Go through each new entry
        $result = true;
        foreach ($objects as $o) {
            // Construct the new record
            $rec = new stdClass();
            $rec->distributorid = $this->sloodle_distributor_instance->id;
            $rec->name = sloodle_clean_for_db($o);
            // Insert it
            if (!sloodle_insert_record('sloodle_distributor_entry', $rec)) $result = false;
        }
    
        return $result;
    }

    
    /**
    * Sets the UUID of the XMLRPC channel used for requests.
    * @param string $uuid The UUID of an XMLRPC channel
    * @return bool True if successful, or false if not
    */
    function set_channel($uuid)
    {
        // Update the values
        $this->sloodle_distributor_instance->channel = $uuid;
        $this->sloodle_distributor_instance->timeupdated = time();
        // Update the database
        return sloodle_update_record('sloodle_distributor', $this->sloodle_distributor_instance);
    }
    
    
    /**
    * Request that the specified object be sent to the specified avatar.
    * @param string $objname Name of the object to send
    * @param string $uuid UUID of the avatar to send the object to
    * @return bool True if successful, or false if not.
    */
    function send_object($objname, $uuid)
    {
        // Check that the object exists in this distributor
        if (!sloodle_record_exists('sloodle_distributor_entry', 'distributorid', $this->distrib_id, 'name', $objname)) return false;
        // Send the XMLRPC request
        return sloodle_send_xmlrpc_message($this->sloodle_distributor_instance->channel, 0, "1|OK\\nSENDOBJECT|$uuid|$objname");
    }
    
    
// BACKUP AND RESTORE //
    
    /**
    * Backs-up secondary data regarding this module.
    * That includes everything except the main 'sloodle' database table for this instance.
    * @param $bf Handle to the file which backup data should be written to.
    * @param bool $includeuserdata Indicates whether or not to backup 'user' data, i.e. any content. Most SLOODLE tools don't have any user data.
    * @return bool True if successful, or false on failure.
    */
    function backup($bf, $includeuserdata)
    {
        // The only thing we can backup is the ID.
        // Everything depends on a Vending Machine in-world connecting to the site.
        fwrite($bf, full_tag('ID', 5, false, $this->sloodle_distributor_instance->id));
        return true;
    }

    
    /**
    * Restore this module's secondary data into the database.
    * This ignores any member data, so can be called statically.
    * @param int $sloodleid The ID of the primary SLOODLE entry this restore belongs to (i.e. the ID of the record in the "sloodle" table)
    * @param array $info An associative array representing the XML backup information for the secondary module data
    * @param bool $includeuserdata Indicates whether or not to restore user data
    * @return bool True if successful, or false on failure.
    */
    function restore($sloodleid, $info, $includeuserdata)
    {
        // Construct the database record
        $distributor = new object();
        $distributor->sloodleid = $sloodleid;
        $distributor->channel = '';
        $distributor->timeupdated = 0;            
        
        $newid = sloodle_insert_record('sloodle_distributor', $distributor);
    
        return true;
    }
    
    
    /**
    * Gets the name of the user data required by this type, or an empty string if none is required.
    * For example, a chatroom would use the name "Messages" for user data.
    * Note that this should respect current language settings in Moodle.
    * @return string Localised name of the user data.
    */
    function get_user_data_name()
    {
        return '';
    }

    
    /**
    * Gets the number of user data records to be backed-up.
    * @return int A count of the number of user data records which can be backed-up.
    */
    function get_user_data_count()
    {
        return 0;
    }
    
    
// ACCESSORS //

    /**
    * Gets the name of this module instance.
    * @return string The name of this controller
    */
    function get_name()
    {
        return $this->sloodle_module_instance->name;
    }

    
    /**
    * Gets the intro description of this module instance, if available.
    * @return string The intro description of this controller
    */
    function get_intro()
    {
        return $this->sloodle_module_instance->intro;
    }

    
    /**
    * Gets the identifier of the course this controller belongs to.
    * @return mixed Course identifier. Type depends on VLE. (In Moodle, it will be an integer).
    */
    function get_course_id()
    {
        return (int)$this->sloodle_module_instance->course;
    }

    
    /**
    * Gets the time at which this instance was created, or 0 if unknown.
    * @return int Timestamp
    */
    function get_creation_time()
    {
        return $this->sloodle_module_instance->timecreated;
    }

    
    /**
    * Gets the time at which this instance was last modified, or 0 if unknown.
    * @return int Timestamp
    */
    function get_modification_time()
    {
        return $this->sloodle_module_instance->timemodified;
    }
    
    
    /**
    * Gets the short type name of this instance.
    * @return string
    */
    static function get_type()
    {
        return SLOODLE_TYPE_DISTRIB;
    }


    /**
    * Gets the full type name of this instance, according to the current language pack, if available.
    * Note: should be overridden by sub-classes.
    * @return string Full type name if possible, or the short name otherwise.
    */
    static function get_type_full()
    {
        return get_string('moduletype:'.SLOODLE_TYPE_DISTRIB, 'sloodle');
    }

}

