<?php
/**
 * 
 * $Id$
 * 
 * Represents a document subscription.
 *
 * Licensed under the GNU GPL. For full terms see the file COPYING.
 *
 * @version $Revision$ 
 * @author Michael Joseph <michael@jamwarehouse.com>, Jam Warehouse (Pty) Ltd, South Africa
 *
 * @package lib.subscriptions
 */
class DocumentSubscription {
    
    /**
     * Primary key
     */
    var $iID;
    /**
     * The ID of the document subscribed to
     */
    var $iDocumentID;
    /**
     * The ID of the user subscribed to the document
     */
    var $iUserID;
    
    /**
     * Creates a new document subscription object
     *
     * @param integer the document ID
     * @param integer the user ID
     */
    function DocumentSubscription($iDocumentID, $iUserID) {
		//id of -1 means that the object has not yet been stored in the database
        $this->iID = -1;
        $this->iDocumentID = $iDocumentID;
        $this->iUserID = $iUserID;
    }
    
    /**
	 * Get the primary key of the current document subscription object
	 *
	 * @return integer primary key of document subscription
	 */
	function getID() {
		return $this->iID;
	}
    
    /**
	 * Get the primary key of the document.
	 *
	 * @return integer primary key of document
	 */
	function getDocumentID() {
		return $this->iDocumentID;
	}
    
	/**
	 * Set the document id
	 *
	 * @param integer new document primary key
	 */
	function setDocumentID($iNewValue) {
		$this->iDocumentID = $iNewValue;
	}
    
    /**
	 * Get the primary key of the user
	 *
	 * @return integer primary key of user
	 */
	function getUserID() {
		return $this->iUserID;
	}
    
	/**
	 * Set the user id
	 *
	 * @param integer new user primary key
	 */
	function setUserID($iNewValue) {
		$this->iUserID = $iNewValue;
	}
    
	/**
 	 * Create the current document subscription in the database
	 *
	 * @return boolean true and set $this->iID with new primary key, false otherwise and set $_SESSION["errorMessage"]
	 */
	function create() {
		global $default, $lang_err_database; $lang_err_object_exists;
		//if the object has not already been stored		
		if ($this->iID < 0) {
			$sql = $default->db;
			$result = $sql->query("INSERT INTO " . $default->owl_document_subscriptions_table . " (user_id, document_id) " .
						          "VALUES ($this->iUserID, $this->iDocumentID)");
			if ($result) {
				$this->iID = $sql->insert_id();
				return true;
			}
			$_SESSION["errorMessage"] = $lang_err_database;
			return false;
		}
		$_SESSION["errorMessage"] = $lang_err_object_exists . "id = " . $this->iID . " table = document_subscriptions";
		return false;
	}
	
	/**
	 * Update the current document subscription values in the database
	 *
	 * @return boolean true on successful update, false otherwise and set $_SESSION["errorMessage"]
	 */
	function update() {
		global $default, $lang_err_database, $lang_err_object_key;
		//can only update the object if it has already been stored
		if ($this->iID >= 0) {
			$sql = $default->db;
			$result = $sql->query("UPDATE " . $default->owl_document_subscriptions_table . " SET " .
							      "user_id = $this->iUserID, " .
                                  "document_id = $this->iDocumentID " .
                                  "WHERE id = " . $this->iID);
			if ($result) {
				return true;
			}
			$_SESSION["errorMessage"] = $lang_err_database;
			return false;			
		}
		$_SESSION["errorMessage"] = $lang_err_object_key;		
	}
	
	
	/**
	* Delete the current object from the database
	*
	* @return boolean true and reset id to -1 on successful delete, false otherwise and set $_SESSION["errorMessage"]
	*/
	function delete() {
		global $default, $lang_err_database, $lang_err_object_key;
		if ($this->iID >= 0) {
			$sql = $default->db;
			$result = $sql->query("DELETE FROM " . $default->owl_document_subscriptions_table . " WHERE id = " . $this->iID);
			if ($result) {
				$this->iID = -1;
				return true;
			}
			$_SESSION["errorMessage"] = $lang_err_database;
			return false;
		}
		$_SESSION["errorMessage"] = $lang_err_object_key;
		return false;
		
	}
	
	/**
	* Static function.  
	* Given a document subscription primary key will create
	* a document subscription object and populate it with the corresponding
	* database values
	*
	* @param integer primary key of document subscription to get
	*
	* @return object document subscription object on successful retrieval, false otherwise and set $_SESSION["errorMessage"]
	*/
	function get($iDocumentSubscriptionID) {
		global $default,  $lang_err_object_not_exist;
		$sql = $default->db;
		$sql->query("SELECT * FROM " . $default->owl_document_subscriptions_table . " WHERE id = " . $iDocumentSubscriptionID);
		if ($sql->next_record()) {
			$oDocumentSubscription = & new DocumentSubscription($sql->f("document_id"), $sql->f("user_id"));
            $oDocumentSubscription->iID = $iDocumentSubscriptionID;
			return $oDocumentSubscription;
		} 
 		$_SESSION["errorMessage"] = $lang_err_object_not_exist . "id = " . $iDocumentSubscriptionID . " table = document_subscriptions";
		return false;
	}    
}
?>