<?php
# Lifter002: TODO
# Lifter007: TODO
# Lifter003: TODO
# Lifter010: TODO
/**
 * Beschreibung
 *
 * @author      Alexander Willner <mail@AlexanderWillner.de>
 * @copyright   2004 Stud.IP-Project
 * @access      public
 * @package     evaluation
 * @modulegroup evaluation_modules
 *
 */

// +--------------------------------------------------------------------------+
// This file is part of Stud.IP
// Copyright (C) 2001-2004 Stud.IP
// +--------------------------------------------------------------------------+
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or 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 General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
// +--------------------------------------------------------------------------+

require_once 'lib/evaluation/evaluation.config.php';
require_once EVAL_FILE_OBJECTDB;


class EvaluationAnswerDB extends EvaluationObjectDB
{
    /**
     * Constructor
     * @access   public
     */
    public function __construct()
    {
        parent::__construct();
        $this->instanceof = 'EvalANSWERDB';
    }

    /**
     * Loads answers of a group from the DB
     * @access  public
     * @param EvaluationAnswer   &&$answerObject The answer object
     */
    public function load(&$answerObject)
    {
        /* load answer --------------------------------------------------------- */
        $row = DBManager::get()->fetchOne(
            "SELECT * FROM evalanswer WHERE evalanswer_id= ?", [$answerObject->getObjectID()]
        );
        if (!count($row)) {
            return $this->throwError(2, _("Keine Antwort mit dieser ID gefunden."));
        }

        $answerObject->setObjectID($row['evalanswer_id']);
        $answerObject->setParentID($row['parent_id']);
        $answerObject->setPosition($row['position']);
        $answerObject->setText($row['text']);
        $answerObject->setValue($row['value']);
        $answerObject->setRows($row['rows']);
        $answerObject->setResidual($row['residual']);
    }


    /**
     * Loads the votes from the users for this answer
     * @access   public
     * @param EvaluationAnswer   &$answerObject The answer object
     */
    function loadVotes(&$answerObject)
    {
        /* load users -------------------------------------------------------- */
        $result = DBManager::get()->fetchFirst("SELECT user_id FROM evalanswer_user
                                            WHERE evalanswer_id= ?", [$answerObject->getObjectID()]);
        foreach ($result as $row) {
            $answerObject->addUserID($row, NO);
        }
    }
    /* ----------------------------------------------------------- end: users */

    /**
     * Writes answers into the DB
     * @access    public
     * @param EvaluationAnswer   &$answerObject The answerobject
     * @throws    error
     */
    function save(&$answerObject)
    {
        /* save answers -------------------------------------------------------- */
        DBManager::get()->execute(
            "REPLACE INTO evalanswer SET
                `evalanswer_id`   = ?,
                `parent_id`       = ?,
                `position`        = ?,
                `text`            = ?,
                `value`           = ?,
                `rows`            = ?,
                `residual`        = ?
                ",
            [$answerObject->getObjectID(),
                $answerObject->getParentID(),
                $answerObject->getPosition(),
                $answerObject->getText(),
                $answerObject->getValue(),
                $answerObject->getRows(),
                $answerObject->isResidual()]);
        /* ----------------------------------------------------- end: answersave */

        /* connect answer to users --------------------------------------------- */
        while ($userID = $answerObject->getNextUserID()) {
            DBManager::get()->execute(
                "INSERT INTO evalanswer_user SET
                    evalanswer_id   = ?,
                    user_id         = ?,
                    evaldate        = UNIX_TIMESTAMP()",
                [$answerObject->getObjectID(), $userID]);
        }
        /* ----------------------------------------------------- end: connecting */

    } // saved

    /**
     * Deletes all votes from the users for this answers
     * @access   public
     * @param EvaluationAnswer   &$answerObject The answer object
     */
    function resetVotes(&$answerObject)
    {
        /* delete userconnects ------------------------------------------------- */
        DBManager::get()->execute("
        DELETE FROM evalanswer_user
            WHERE evalanswer_id   = ?",
            [$answerObject->getObjectID()]);
        /* ------------------------------------------------------- end: deleting */
    }

    /**
     * Deletes a answer
     * @access public
     * @param EvaluationAnswer   &$answerObject The answer to delete
     * @throws  error
     */
    function delete(&$answerObject)
    {
        /* delete answer ----------------------------------------------------- */
        DBManager::get()->execute("
        DELETE FROM evalanswer
            WHERE evalanswer_id   = ?",
            [$answerObject->getObjectID()]);
        /* ------------------------------------------------------- end: deleting */
        $this->resetVotes($answerObject);
    } // deleted


    /**
     * Checks if answer with this ID exists
     * @access  public
     * @param string $answerID The answerID
     * @return  bool     YES if exists
     */
    function exists($answerID)
    {
        $result = DBManager::get()->fetchOne("SELECT 1 FROM evalanswer
                                            WHERE evalanswer_id= ?", [$answerID]);
        if (count($result) > 0)
            return true;
        return false;
    }


    /**
     * Adds the children to a parent object
     * @access  public
     * @param EvaluationObject  &$parentObject The parent object
     */
    public static function addChildren(&$parentObject)
    {
        $result = DBManager::get()->fetchFirst("SELECT evalanswer_id FROM evalanswer
                                            WHERE parent_id= ? ORDER by position",
            [$parentObject->getObjectID()]);

        $loadChildren =
            $parentObject->loadChildren == EVAL_LOAD_ALL_CHILDREN ? EVAL_LOAD_ALL_CHILDREN : EVAL_LOAD_NO_CHILDREN;

        foreach ($result as $row) {
            $child = new EvaluationAnswer($row, $parentObject, $loadChildren);
            $parentObject->addChild($child);
        }
    }

    /**
     * Returns the type of an objectID
     * @access public
     * @param string $objectID The objectID
     * @return string  INSTANCEOF_x, else NO
     */
    function getType($objectID)
    {
        if ($this->exists($objectID)) {
            return INSTANCEOF_EVALANSWER;
        } else {
            return NO;
        }
    }

    /**
     * Returns the id from the parent object
     * @access public
     * @param string $objectID The object id
     * @return string  The id from the parent object
     */
    public static function getParentID($objectID)
    {
        return DBManager::get()->fetchColumn("SELECT parent_id FROM evalanswer
                                            WHERE evalanswer_id = ?",
            [$objectID]);
    }

    /**
     * Give all textanswers for a user and question for the export
     * @access  public
     * @param string $questionID The question id
     * @param string $userID The user id
     */
    function getUserAnwerIDs($questionID, $userID)
    {
        /* ask database ------------------------------------------------------- */
        $sql = "SELECT a.evalanswer_id as ttt FROM evalanswer a, evalanswer_user b
                    WHERE a.parent_id = ? AND a.evalanswer_id = b.evalanswer_id";
        if (empty ($userID))
            $answer_ids = DBManager::get()->fetchFirst($sql, [$questionID]);
        else
            $answer_ids = DBManager::get()->fetchFirst($sql . " AND b.user_id = ?", [$questionID, $userID]);
        /* -------------------------------------------------------- end: asking */
        return $answer_ids;
    }

    /**
     * Checks whether a user has voted for an answer
     * @access   public
     * @param string $answerID The answer id
     * @param string $userID The user id
     * @return   boolean  YES if user has voted for the answer
     */
    function hasVoted($answerID, $userID)
    {
        $result = DBManager::get()->fetchOne("SELECT 1 FROM evalanswer_user
                                            WHERE evalanswer_id= ? AND user_id", [$answerID, $userID]);
        if (count($result) > 0)
            return true;
        return false;
    }

    function getAllAnswers($question_id, $userID, $only_user_answered = false)
    {
        if ($only_user_answered)
            return DBManager::get()->fetchAll("
                SELECT evalanswer.*, COUNT(IF(user_id=?,1,NULL)) AS has_voted
                FROM evalanswer LEFT JOIN evalanswer_user USING(evalanswer_id)
                WHERE parent_id = ? AND user_id = ?
                GROUP BY evalanswer.evalanswer_id ORDER BY position",
                [$userID, $question_id, $userID]);
        else
            return DBManager::get()->fetchAll("
                SELECT evalanswer.*, COUNT(IF(user_id=?,1,NULL)) AS has_voted
                FROM evalanswer LEFT JOIN evalanswer_user USING(evalanswer_id)
                WHERE parent_id = ?
                GROUP BY evalanswer.evalanswer_id ORDER BY position",
                [$userID, $question_id]);
    }
}

?>