<?php

///////////////////////////////////////////////////////////////////////////
//                                                                       //
// NOTICE OF COPYRIGHT                                                   //
//                                                                       //
// Moodle - Modular Object-Oriented Dynamic Learning Environment         //
//          http://moodle.org                                            //
//                                                                       //
// Copyright (C) 1999 onwards Martin Dougiamas and others                //
//                                                                       //
// 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     //
// (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 General Public License for more details:                          //
//                                                                       //
//          http://www.gnu.org/copyleft/gpl.html                         //
//                                                                       //
///////////////////////////////////////////////////////////////////////////

/**
 * Page to edit quizzes
 *
 * This page generally has two columns:
 * The right column lists all available questions in a chosen category and
 * allows them to be edited or more to be added. This column is only there if
 * the quiz does not already have student attempts
 * The left column lists all questions that have been added to the current quiz.
 * The lecturer can add questions from the right hand list to the quiz or remove them
 *
 * The script also processes a number of actions:
 * Actions affecting a quiz:
 * up and down  Changes the order of questions and page breaks
 * addquestion  Adds a single question to the quiz
 * add          Adds several selected questions to the quiz
 * addrandom    Adds a certain number of random questions to the quiz
 * repaginate   Re-paginates the quiz
 * delete       Removes a question from the quiz
 * savechanges  Saves the order and grades for questions in the quiz
 *
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 * @package quiz
 *//** */

require_once('../../config.php');
require_once($CFG->dirroot . '/mod/quiz/editlib.php');
require_once($CFG->dirroot . '/question/category_class.php');
$PAGE->requires->yui2_lib('container');
$PAGE->requires->yui2_lib('dragdrop');

/**
 * Callback function called from question_list() function
 * (which is called from showbank())
 * Displays button in form with checkboxes for each question.
 */
function module_specific_buttons($cmid, $cmoptions) {
    global $OUTPUT;
    if ($cmoptions->hasattempts) {
        $disabled = 'disabled="disabled" ';
    } else {
        $disabled = '';
    }
    $straddtoquiz = get_string('addtoquiz', 'quiz');
    $out = '<input type="submit" name="add" value="' . $OUTPUT->larrow() . ' ' . $straddtoquiz .
            '" ' . $disabled . "/>\n";
    return $out;
}

/**
 * Callback function called from question_list() function
 * (which is called from showbank())
 */
function module_specific_controls($totalnumber, $recurse, $category, $cmid, $cmoptions) {
    global $QTYPES, $OUTPUT;
    $out = '';
    $catcontext = get_context_instance_by_id($category->contextid);
    if (has_capability('moodle/question:useall', $catcontext)) {
        if ($cmoptions->hasattempts) {
            $disabled = 'disabled="disabled"';
        } else {
            $disabled = '';
        }
        $randomusablequestions =
                $QTYPES['random']->get_usable_questions_from_category($category->id, $recurse, '0');
        $maxrand = count($randomusablequestions);
        if ($maxrand > 0) {
            for ($i = 1; $i <= min(10, $maxrand); $i++) {
                $randomcount[$i] = $i;
            }
            for ($i = 20; $i <= min(100, $maxrand); $i += 10) {
                $randomcount[$i] = $i;
            }
            $straddtoquiz = get_string('addtoquiz', 'quiz');
            $out = '<strong><label for="menurandomcount">'.get_string('addrandomfromcategory', 'quiz').
                    '</label></strong><br />';
            $attributes = array();
            $attributes['disabled'] = $cmoptions->hasattempts ? 'disabled' : null;
            $select = html_writer::select($randomcount, 'randomcount', '1', null, $attributes);
            $out .= get_string('addrandom', 'quiz', $select);
            $out .= '<input type="hidden" name="recurse" value="'.$recurse.'" />';
            $out .= '<input type="hidden" name="categoryid" value="' . $category->id . '" />';
            $out .= ' <input type="submit" name="addrandom" value="'.
                    $straddtoquiz.'" '.$disabled.' />';
            $out .= $OUTPUT->old_help_icon('random', get_string('random', 'quiz'), 'quiz');
        }
    }
    return $out;
}

list($thispageurl, $contexts, $cmid, $cm, $quiz, $pagevars) =
        question_edit_setup('editq', '/mod/quiz/edit.php', true);
$PAGE->set_url($thispageurl);
$PAGE->set_pagelayout('base');

$defaultcategoryobj = question_make_default_categories($contexts->all());
$defaultcategoryid = $defaultcategoryobj->id;
$defaultcategorycontext = $defaultcategoryobj->contextid;
$defaultcategory = $defaultcategoryid . ',' . $defaultcategorycontext;

//these params are only passed from page request to request while we stay on
//this page otherwise they would go in question_edit_setup
$quiz_reordertool = optional_param('reordertool', 0, PARAM_BOOL);
$quiz_qbanktool = optional_param('qbanktool', -1, PARAM_BOOL);
if ($quiz_qbanktool > -1) {
    $thispageurl->param('qbanktool', $quiz_qbanktool);
    set_user_preference('quiz_qbanktool_open', $quiz_qbanktool);
} else {
    $quiz_qbanktool = get_user_preferences('quiz_qbanktool_open', 0);
}

//will be set further down in the code
$quizhasattempts = quiz_has_attempts($quiz->id);

if ($quiz_reordertool != 0) {
    $thispageurl->param('reordertool', $quiz_reordertool);
}

$strquizzes = get_string('modulenameplural', 'quiz');
$strquiz = get_string('modulename', 'quiz');
$streditingquestions = get_string('editquestions', 'quiz');

//this just does not work for at least finnish, where words are conjugated:
//$streditingquiz = get_string('editinga', 'moodle', $strquiz);
$streditingquiz = get_string('editingquiz', 'quiz');
$strorderingquiz = get_string('orderingquiz', 'quiz');
$pagetitle = $streditingquiz;
if ($quiz_reordertool) {
    $pagetitle = $strorderingquiz;
}
// Get the course object and related bits.
$course = $DB->get_record('course', array('id' => $quiz->course));
if (!$course) {
    print_error('invalidcourseid', 'error');
}

$questionbank = new quiz_question_bank_view($contexts, $thispageurl, $course, $cm);
$questionbank->set_quiz_has_attempts($quizhasattempts);

// Log this visit.
add_to_log($cm->course, 'quiz', 'editquestions',
            "view.php?id=$cm->id", "$quiz->id", $cm->id);

// You need mod/quiz:manage in addition to question capabilities to access this page.
require_capability('mod/quiz:manage', $contexts->lowest());

if (empty($quiz->grades)) {  // Construct an array to hold all the grades.
    $quiz->grades = quiz_get_all_question_grades($quiz);
}

// Process commands ============================================================
if ($quiz->shufflequestions) {
    // Strip page breaks before processing actions, so that re-ordering works
    // as expected when shuffle questions is on.
    $quiz->questions = quiz_repaginate($quiz->questions, 0);
}

// Get the list of question ids had their check-boxes ticked.
$selectedquestionids = array();
$params = (array) data_submitted();
foreach ($params as $key => $value) {
    if (preg_match('!^s([0-9]+)$!', $key, $matches)) {
        $selectedquestionids[] = $matches[1];
    }
}

if (($up = optional_param('up', false, PARAM_INT)) && confirm_sesskey()) {
    $quiz->questions = quiz_move_question_up($quiz->questions, $up);
    quiz_save_new_layout($quiz);
    redirect($thispageurl);
}

if (($down = optional_param('down', false, PARAM_INT)) && confirm_sesskey()) {
    $quiz->questions = quiz_move_question_down($quiz->questions, $down);
    quiz_save_new_layout($quiz);
    redirect($thispageurl);
}

if (optional_param('repaginate', false, PARAM_BOOL) && confirm_sesskey()) {
    // Re-paginate the quiz
    $questionsperpage = optional_param('questionsperpage', $quiz->questionsperpage, PARAM_INT);
    $quiz->questions = quiz_repaginate($quiz->questions, $questionsperpage );
    quiz_save_new_layout($quiz);
}

if (($addquestion = optional_param('addquestion', 0, PARAM_INT)) && confirm_sesskey()) {
/// Add a single question to the current quiz
    $addonpage = optional_param('addonpage', 0, PARAM_INT);
    quiz_add_quiz_question($addquestion, $quiz, $addonpage);
    quiz_update_sumgrades($quiz);
    quiz_delete_previews($quiz);
    redirect($thispageurl);
}

if (optional_param('add', false, PARAM_BOOL) && confirm_sesskey()) {
/// Add selected questions to the current quiz
    $rawdata = (array) data_submitted();
    foreach ($rawdata as $key => $value) {    // Parse input for question ids
        if (preg_match('!^q([0-9]+)$!', $key, $matches)) {
            $key = $matches[1];
            quiz_add_quiz_question($key, $quiz);
        }
    }
    quiz_update_sumgrades($quiz);
    quiz_delete_previews($quiz);
    redirect($thispageurl);
}

$qcobject = new question_category_object($pagevars['cpage'], $thispageurl,
        $contexts->having_one_edit_tab_cap('categories'), $defaultcategoryid,
        $defaultcategory, null, $contexts->having_cap('moodle/question:add'));

$newrandomcategory = false;
$newquestioninfo = quiz_process_randomquestion_formdata($qcobject);
if ($newquestioninfo && $newquestioninfo != 'cancelled') {
    $newrandomcategory = $newquestioninfo->newrandomcategory;
    if (!$newrandomcategory) {
        print_error('cannotcreatecategory');
    } else {
        add_to_log($quiz->course, 'quiz', 'addcategory',
                "view.php?id=$cm->id", $newrandomcategory, $cm->id);
    }
}

if ((optional_param('addrandom', false, PARAM_BOOL) || $newrandomcategory) && confirm_sesskey()) {

    /// Add random questions to the quiz
    $recurse = optional_param('recurse', 0, PARAM_BOOL);
    $addonpage = optional_param('addonpage', 0, PARAM_INT);
    if ($newrandomcategory) {
        $categoryid = $newrandomcategory;
        $randomcount = optional_param('randomcount', 1, PARAM_INT);
    } else {
        $categoryid = required_param('categoryid', PARAM_INT);
        $randomcount = required_param('randomcount', PARAM_INT);
    }
    // load category
    $category = $DB->get_record('question_categories', array('id' => $categoryid));
    if (!$category) {
        print_error('invalidcategoryid', 'error');
    }
    $catcontext = get_context_instance_by_id($category->contextid);
    require_capability('moodle/question:useall', $catcontext);
    $category->name = $category->name;
    // Find existing random questions in this category that are
    // not used by any quiz.
    if ($existingquestions = $DB->get_records_sql(
            "SELECT q.id,q.qtype FROM {question} q
            WHERE qtype = '" . RANDOM . "'
                AND category = ?
                AND " . $DB->sql_compare_text('questiontext') . " = ?
                AND NOT EXISTS (SELECT * FROM {quiz_question_instances} WHERE question = q.id)
            ORDER BY id", array($category->id, $recurse))) {
        // Take as many of these as needed.
        while (($existingquestion = array_shift($existingquestions)) && $randomcount > 0) {
            quiz_add_quiz_question($existingquestion->id, $quiz, $addonpage);
            $randomcount--;
        }
    }

    // If more are needed, create them.
    if ($randomcount > 0) {
        $form->questiontext = $recurse; // we use the questiontext field
                // to store the info on whether to include
                // questions in subcategories
        $form->questiontextformat = 0;
        $form->image = '';
        $form->defaultgrade = 1;
        $form->hidden = 1;
        for ($i = 0; $i < $randomcount; $i++) {
            $form->category = $category->id . ',' . $category->contextid;
            $form->stamp = make_unique_id_code(); // Set the unique
                    //code (not to be changed)
            $question = new stdClass;
            $question->qtype = RANDOM;
            $question = $QTYPES[RANDOM]->save_question($question, $form,
                    $course);
            if(!isset($question->id)) {
                print_error('cannotinsertrandomquestion', 'quiz');
            }
            quiz_add_quiz_question($question->id, $quiz, $addonpage);
        }
    }

    quiz_update_sumgrades($quiz);
    quiz_delete_previews($quiz);
    redirect($thispageurl);
}

if (optional_param('addnewpagesafterselected', null, PARAM_CLEAN) && !empty($selectedquestionids) && confirm_sesskey()) {
    foreach ($selectedquestionids as $questionid) {
        $quiz->questions = quiz_add_page_break_after($quiz->questions, $questionid);
    }
    quiz_save_new_layout($quiz);
    redirect($thispageurl);
}

$addpage = optional_param('addpage', false, PARAM_INT);
if ($addpage !== false && confirm_sesskey()) {
    $quiz->questions = quiz_add_page_break_at($quiz->questions, $addpage);
    quiz_save_new_layout($quiz);
    redirect($thispageurl);
}

$deleteemptypage = optional_param('deleteemptypage', false, PARAM_INT);
if (($deleteemptypage !== false) && confirm_sesskey()) {
    $quiz->questions = quiz_delete_empty_page($quiz->questions, $deleteemptypage);
    quiz_save_new_layout($quiz);
    redirect($thispageurl);
}

$remove = optional_param('remove', false, PARAM_INT);
if (($remove = optional_param('remove', false, PARAM_INT)) && confirm_sesskey()) {
    quiz_remove_question($quiz, $remove);
    quiz_update_sumgrades($quiz);
    quiz_delete_previews($quiz);
    redirect($thispageurl);
}

if (optional_param('quizdeleteselected', false, PARAM_BOOL) && !empty($selectedquestionids) && confirm_sesskey()) {
    foreach ($selectedquestionids as $questionid) {
        quiz_remove_question($quiz, $questionid);
    }
    quiz_update_sumgrades($quiz);
    quiz_delete_previews($quiz);
    redirect($thispageurl);
}

if (optional_param('savechanges', false, PARAM_BOOL) && confirm_sesskey()) {
    $oldquestions = explode(',', $quiz->questions); // the questions in the old order
    $questions = array(); // for questions in the new order
    $rawdata = (array) data_submitted();
    $moveonpagequestions = array();
    $moveselectedonpage = optional_param('moveselectedonpagetop', 0, PARAM_INT);
    if (!$moveselectedonpage) {
        $moveselectedonpage = optional_param('moveselectedonpagebottom', 0, PARAM_INT);
    }

    foreach ($rawdata as $key => $value) {
        if (preg_match('!^g([0-9]+)$!', $key, $matches)) {
            /// Parse input for question -> grades
            $questionid = $matches[1];
            $quiz->grades[$questionid] = clean_param($value, PARAM_FLOAT);
            quiz_update_question_instance($quiz->grades[$questionid], $questionid, $quiz->id);
            quiz_delete_previews($quiz);
            quiz_update_sumgrades($quiz);

        } else if (preg_match('!^o(pg)?([0-9]+)$!', $key, $matches)) {
            /// Parse input for ordering info
            $questionid = $matches[2];
            // Make sure two questions don't overwrite each other. If we get a second
            // question with the same position, shift the second one along to the next gap.
            $value = clean_param($value, PARAM_INTEGER);
            while (array_key_exists($value, $questions)) {
                $value++;
            }
            if ($matches[1]) {
                // This is a page-break entry.
                $questions[$value] = 0;
            } else {
                $questions[$value] = $questionid;
            }
        }
    }

    // If ordering info was given, reorder the questions
    if ($questions) {
        ksort($questions);
        $questions[] = 0;
        $quiz->questions = implode(',', $questions);
        quiz_save_new_layout($quiz);
        quiz_delete_previews($quiz);
    }

    //get a list of questions to move, later to be added in the appropriate
    //place in the string
    if ($moveselectedonpage) {
        $questions = explode(',', $quiz->questions);
        $newquestions = array();
        //remove the questions from their original positions first
        foreach ($questions as $questionid) {
            if (!in_array($questionid, $selectedquestionids)) {
                $newquestions[] = $questionid;
            }
        }
        $questions = $newquestions;

        //move to the end of the selected page
        $pagebreakpositions = array_keys($questions, 0);
        $numpages = count($pagebreakpositions);
        // Ensure the target page number is in range.
        $moveselectedonpage = max(1, min($moveselectedonpage, $pagebreakpositions));
        $moveselectedpos = $pagebreakpositions[$moveselectedonpage - 1];
        array_splice($questions, $moveselectedpos, 0, $selectedquestionids);
        $quiz->questions = implode(',', $questions);
        quiz_save_new_layout($quiz);
        quiz_delete_previews($quiz);
    }

    // If rescaling is required save the new maximum
    $maxgrade = optional_param('maxgrade', -1, PARAM_FLOAT);
    if ($maxgrade >= 0) {
        quiz_set_grade($maxgrade, $quiz);
    }

    redirect($thispageurl);
}

$questionbank->process_actions($thispageurl, $cm);

// End of process commands =====================================================

// Print the header.
$questionbankmanagement = '<a href="'.$CFG->wwwroot.
        '/question/edit.php?courseid='.$course->id.'">'.
        get_string('questionbankmanagement', 'quiz').'</a> ';

$PAGE->navbar->add($pagetitle);
$PAGE->requires->skip_link_to('questionbank',  get_string('skipto', 'access', get_string('questionbank', 'question')));
$PAGE->requires->skip_link_to('quizcontentsblock',  get_string('skipto', 'access', get_string('questionsinthisquiz', 'quiz')));

$PAGE->set_title($pagetitle);
$PAGE->set_button($questionbankmanagement);
echo $OUTPUT->header();

// Initialise the JavaScript.
$quizeditconfig = new stdClass;
$quizeditconfig->url = $thispageurl->out(true, array('qbanktool' => '0'));
$quizeditconfig->dialoglisteners = array();
$numberoflisteners = max(quiz_number_of_pages($quiz->questions), 1);
for ($pageiter = 1; $pageiter <= $numberoflisteners; $pageiter++) {
    $quizeditconfig->dialoglisteners[] = 'addrandomdialoglaunch_' . $pageiter;
}
$PAGE->requires->data_for_js('quiz_edit_config', $quizeditconfig);
$PAGE->requires->js('/mod/quiz/edit.js');

// Print the tabs.
$currenttab = 'edit';
$mode = 'editq';
if ($quiz_reordertool) {
    $mode = 'reorder';
}
include('tabs.php');

if ($quiz_qbanktool) {
    $bankclass = '';
    $quizcontentsclass = '';
} else {
    $bankclass = 'collapsed ';
    $quizcontentsclass = 'quizwhenbankcollapsed';
}

echo '<div class="questionbankwindow ' . $bankclass . 'sideblock">';
echo '<div class="header"><div class="title"><h2>';
echo get_string('questionbankcontents', 'quiz') .
        ' <a href="' . $thispageurl->out(true, array('qbanktool' => '1')) .
       '" id="showbankcmd">[' . get_string('show').
       ']</a>
       <a href="' . $thispageurl->out(true, array('qbanktool' => '0')) .
       '" id="hidebankcmd">[' . get_string('hide').
       ']</a>';
echo '</h2></div></div><div class="content">';

echo '<span id="questionbank"></span>';
echo '<div class="container">';
echo '<div id="module" class="module">';
echo '<div class="bd">';
$questionbank->display('editq',
        $pagevars['qpage'],
        $pagevars['qperpage'], $pagevars['qsortorder'],
        $pagevars['qsortorderdecoded'],
        $pagevars['cat'], $pagevars['recurse'], $pagevars['showhidden'],
        $pagevars['showquestiontext']);
echo '</div>';
echo '</div>';
echo '</div>';

echo '</div></div>';

echo '<div class="quizcontents ' . $quizcontentsclass . '" id="quizcontentsblock">';
if ($quiz->shufflequestions) {
    $repaginatingdisabledhtml = 'disabled="disabled"';
    $repaginatingdisabled = true;
    $quiz->questions = quiz_repaginate($quiz->questions, $quiz->questionsperpage);
} else {
    $repaginatingdisabledhtml = '';
    $repaginatingdisabled = false;
}
if ($quiz_reordertool) {
    echo '<div class="repaginatecommand"><button id="repaginatecommand" '.$repaginatingdisabledhtml.'>'.
            get_string('repaginatecommand', 'quiz').'...</button>';
    echo '</div>';
}
echo $OUTPUT->heading($pagetitle.": ".$quiz->name, 2);
echo $OUTPUT->old_help_icon('editconcepts', get_string('basicideasofquiz', 'quiz'), 'quiz', true);
quiz_print_status_bar($quiz);

$tabindex = 0;
if (!$quiz_reordertool) {
    quiz_print_grading_form($quiz, $thispageurl, $tabindex);
}

$notifystrings = array();
if ($quizhasattempts) {
    $reviewlink = '<a href="' . $CFG->wwwroot . '/mod/quiz/report.php?mode=overview&amp;id=' . $cm->id . '">' .
            quiz_num_attempt_summary($quiz, $cm) . '</a>';
    $notifystrings[] = get_string('cannoteditafterattempts', 'quiz', $reviewlink);
}
if ($quiz->shufflequestions) {
    $updateurl = new moodle_url("$CFG->wwwroot/course/mod.php",
            array('return' => 'true', 'update' => $quiz->cmid, 'sesskey' => sesskey()));
    $updatelink = '<a href="'.$updateurl->out().'">' . get_string('updatethis', '',
            get_string('modulename', 'quiz')) . '</a>';
    $notifystrings[] = get_string('shufflequestionsselected', 'quiz', $updatelink);
}
if (!empty($notifystrings)) {
    echo $OUTPUT->box('<p>' . implode('</p><p>', $notifystrings) . '</p>', 'statusdisplay');
}

if ($quiz_reordertool) {
    $perpage= array();
    $perpage[0] = get_string('allinone', 'quiz');
    for ($i = 1; $i <= 50; ++$i) {
        $perpage[$i] = $i;
    }
    $gostring = get_string('go');
    echo '<div id="repaginatedialog"><div class="hd">';
    echo get_string('repaginatecommand', 'quiz');
    echo '</div><div class="bd">';
    echo '<form action="edit.php" method="post">';
    echo '<fieldset class="invisiblefieldset">';
    echo html_writer::input_hidden_params($thispageurl);
    echo '<input type="hidden" name="sesskey" value="'.sesskey().'" />';
    //YUI does not submit the value of the submit button so
            //we need to add the value:
    echo '<input type="hidden" name="repaginate" value="'.$gostring.'" />';
    $attributes = array();
    $attributes['disabled'] = $repaginatingdisabledhtml ? 'disabled' : null;
    $select = html_writer::select($perpage, 'questionsperpage', $quiz->questionsperpage, null, $attributes);
    print_string('repaginate', 'quiz', $select);
    echo '<div class="quizquestionlistcontrols">';
    echo ' <input type="submit" name="repaginate" value="'. $gostring .'" '.$repaginatingdisabledhtml.' />';
    echo '</div></fieldset></form></div></div>';
}

echo '<div class="' . $currenttab . '">';
quiz_print_question_list($quiz, $thispageurl, true,
        $quiz_reordertool, $quiz_qbanktool, $quizhasattempts);
echo '</div>';

// Close <div class="quizcontents">:
echo '</div>';

if (!$quiz_reordertool) {
    // display category adding UI
    ?>
<div id="randomquestiondialog">
<div class="hd"><?php print_string('addrandomquestiontoquiz', 'quiz', $quiz->name); ?>
<span id="pagenumber"><!-- JavaScript will insert the page number here. -->
</span>
</div>
<div class="bd"><?php
$qcobject->display_randomquestion_user_interface();
?></div>
</div>
    <?php
}
echo $OUTPUT->footer();
?>
