<?php
/* For licensing terms, see /license.txt */

/**
 * This script shows a list of courses and allows searching for courses codes
 * and names.
 */
$cidReset = true;
require_once __DIR__.'/../inc/global.inc.php';
$this_section = SECTION_PLATFORM_ADMIN;

api_protect_admin_script();

$sessionId = isset($_GET['session_id']) ? $_GET['session_id'] : null;

/**
 * Get the number of courses which will be displayed.
 *
 * @throws Exception
 *
 * @return int The number of matching courses
 */
function get_number_of_courses()
{
    $course_table = Database::get_main_table(TABLE_MAIN_COURSE);
    $sql = "SELECT COUNT(code) AS total_number_of_items FROM $course_table c";

    if ((api_is_platform_admin() || api_is_session_admin()) &&
        api_is_multiple_url_enabled() && api_get_current_access_url_id() != -1
    ) {
        $access_url_rel_course_table = Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_COURSE);
        $sql .= " INNER JOIN $access_url_rel_course_table url_rel_course
                 ON (c.id = url_rel_course.c_id)";
    }

    if (isset($_GET['keyword'])) {
        $keyword = Database::escape_string("%".$_GET['keyword']."%");
        $sql .= " WHERE (
                        c.title LIKE '".$keyword."' OR
                        c.code LIKE '".$keyword."' OR
                        c.visual_code LIKE '".$keyword."'
                )
        ";
    } elseif (isset($_GET['keyword_code'])) {
        $keyword_code = Database::escape_string("%".$_GET['keyword_code']."%");
        $keyword_title = Database::escape_string("%".$_GET['keyword_title']."%");
        $keyword_category = isset($_GET['keyword_category'])
            ? Database::escape_string("%".$_GET['keyword_category']."%")
            : null;
        $keyword_language = Database::escape_string("%".$_GET['keyword_language']."%");
        $keyword_visibility = Database::escape_string("%".$_GET['keyword_visibility']."%");
        $keyword_subscribe = Database::escape_string($_GET['keyword_subscribe']);
        $keyword_unsubscribe = Database::escape_string($_GET['keyword_unsubscribe']);

        $sql .= " WHERE
                    (c.code LIKE '".$keyword_code."' OR c.visual_code LIKE '".$keyword_code."') AND
                    c.title LIKE '".$keyword_title."' AND
                    c.course_language LIKE '".$keyword_language."' AND
                    c.visibility LIKE '".$keyword_visibility."' AND
                    c.subscribe LIKE '".$keyword_subscribe."' AND
                    c.unsubscribe LIKE '".$keyword_unsubscribe."'
        ";

        if (!empty($keyword_category)) {
            $sql .= " AND c.category_code LIKE '".$keyword_category."' ";
        }
    }

    // adding the filter to see the user's only of the current access_url
    if ((api_is_platform_admin() || api_is_session_admin()) &&
        api_is_multiple_url_enabled() && api_get_current_access_url_id() != -1
    ) {
        $sql .= " AND url_rel_course.access_url_id = ".api_get_current_access_url_id();
    }

    $res = Database::query($sql);
    $obj = Database::fetch_object($res);

    return $obj->total_number_of_items;
}

/**
 * Get course data to display.
 *
 * @param int    $from
 * @param int    $number_of_items
 * @param int    $column
 * @param string $direction
 *
 * @throws Exception
 *
 * @return array
 */
function get_course_data($from, $number_of_items, $column, $direction)
{
    $course_table = Database::get_main_table(TABLE_MAIN_COURSE);

    $sql = "SELECT  
                code AS col0,
                title AS col1,
                code AS col2,
                course_language AS col3,
                category_code AS col4,
                subscribe AS col5,
                unsubscribe AS col6,
                code AS col7,
                visibility AS col8,
                directory as col9,
                visual_code,
                directory,
                course.id
    		FROM $course_table course";

    if ((api_is_platform_admin() || api_is_session_admin()) &&
        api_is_multiple_url_enabled() && api_get_current_access_url_id() != -1
    ) {
        $access_url_rel_course_table = Database::get_main_table(TABLE_MAIN_ACCESS_URL_REL_COURSE);
        $sql .= " INNER JOIN $access_url_rel_course_table url_rel_course
                 ON (course.id = url_rel_course.c_id)";
    }

    if (isset($_GET['keyword'])) {
        $keyword = Database::escape_string("%".trim($_GET['keyword'])."%");
        $sql .= " WHERE (
            title LIKE '".$keyword."' OR
            code LIKE '".$keyword."' OR
            visual_code LIKE '".$keyword."'
        )
        ";
    } elseif (isset($_GET['keyword_code'])) {
        $keyword_code = Database::escape_string("%".$_GET['keyword_code']."%");
        $keyword_title = Database::escape_string("%".$_GET['keyword_title']."%");
        $keyword_category = isset($_GET['keyword_category'])
            ? Database::escape_string("%".$_GET['keyword_category']."%")
            : null;
        $keyword_language = Database::escape_string("%".$_GET['keyword_language']."%");
        $keyword_visibility = Database::escape_string("%".$_GET['keyword_visibility']."%");
        $keyword_subscribe = Database::escape_string($_GET['keyword_subscribe']);
        $keyword_unsubscribe = Database::escape_string($_GET['keyword_unsubscribe']);

        $sql .= " WHERE
                (code LIKE '".$keyword_code."' OR visual_code LIKE '".$keyword_code."') AND
                title LIKE '".$keyword_title."' AND
                course_language LIKE '".$keyword_language."' AND
                visibility LIKE '".$keyword_visibility."' AND
                subscribe LIKE '".$keyword_subscribe."' AND
                unsubscribe LIKE '".$keyword_unsubscribe."'";

        if (!empty($keyword_category)) {
            $sql .= " AND category_code LIKE '".$keyword_category."' ";
        }
    }

    // Adding the filter to see the user's only of the current access_url.
    if ((api_is_platform_admin() || api_is_session_admin()) &&
        api_is_multiple_url_enabled() && api_get_current_access_url_id() != -1
    ) {
        $sql .= " AND url_rel_course.access_url_id=".api_get_current_access_url_id();
    }

    $sql .= " ORDER BY col$column $direction ";
    $sql .= " LIMIT $from, $number_of_items";

    $res = Database::query($sql);
    $courses = [];
    $languages = api_get_languages_to_array();

    $path = api_get_path(WEB_CODE_PATH);
    $coursePath = api_get_path(WEB_COURSE_PATH);

    while ($course = Database::fetch_array($res)) {
        // Place colour icons in front of courses.
        $show_visual_code = $course['visual_code'] != $course[2] ? Display::label($course['visual_code'], 'info') : null;
        $course[1] = get_course_visibility_icon($course[8]).PHP_EOL
            .Display::url(Security::remove_XSS($course[1]), $coursePath.$course[9].'/index.php').PHP_EOL
            .$show_visual_code;
        $course[5] = $course[5] == SUBSCRIBE_ALLOWED ? get_lang('Yes') : get_lang('No');
        $course[6] = $course[6] == UNSUBSCRIBE_ALLOWED ? get_lang('Yes') : get_lang('No');
        $language = isset($languages[$course[3]]) ? $languages[$course[3]] : $course[3];

        $courseCode = $course[0];
        $courseId = $course['id'];

        $actions = [];
        $actions[] = Display::url(
            Display::return_icon('info2.png', get_lang('Information')),
            "course_information.php?code=$courseCode"
        );
        $actions[] = Display::url(
            Display::return_icon('course_home.png', get_lang('Course home')),
            $coursePath.$course['directory'].'/index.php'
        );
        $actions[] = Display::url(
            Display::return_icon('statistics.png', get_lang('Reporting')),
            $path.'tracking/courseLog.php?'.api_get_cidreq_params($courseCode)
        );
        $actions[] = Display::url(
            Display::return_icon('edit.png', get_lang('Edit')),
            $path.'admin/course_edit.php?id='.$courseId
        );
        $actions[] = Display::url(
            Display::return_icon('backup.png', get_lang('Create a backup')),
            $path.'coursecopy/create_backup.php?'.api_get_cidreq_params($courseCode)
        );
        $actions[] = Display::url(
            Display::return_icon('delete.png', get_lang('Delete')),
            $path.'admin/course_list.php?delete_course='.$courseCode,
            [
                'onclick' => "javascript: if (!confirm('"
                    .addslashes(api_htmlentities(get_lang('Please confirm your choice'), ENT_QUOTES))."')) return false;",
            ]
        );

        $courseItem = [
            $course[0],
            $course[1],
            $course[2],
            $language,
            $course[4],
            $course[5],
            $course[6],
            implode(PHP_EOL, $actions),
        ];
        $courses[] = $courseItem;
    }

    return $courses;
}

/**
 * Get course data to display filtered by session name.
 *
 * @param int    $from
 * @param int    $number_of_items
 * @param int    $column
 * @param string $direction
 *
 * @throws Exception
 *
 * @return array
 */
function get_course_data_by_session($from, $number_of_items, $column, $direction)
{
    $course_table = Database::get_main_table(TABLE_MAIN_COURSE);
    $session_rel_course = Database::get_main_table(TABLE_MAIN_SESSION_COURSE);
    $session = Database::get_main_table(TABLE_MAIN_SESSION);

    $sql = "SELECT
                c.code AS col0,
                c.title AS col1,
                c.code AS col2,
                c.course_language AS col3,
                c.category_code AS col4,
                c.subscribe AS col5,
                c.unsubscribe AS col6,
                c.code AS col7,
                c.visibility AS col8,
                c.directory as col9,
                c.visual_code
            FROM $course_table c
            INNER JOIN $session_rel_course r
            ON c.id = r.c_id
            INNER JOIN $session s
            ON r.session_id = s.id
            ";

    if (isset($_GET['session_id']) && !empty($_GET['session_id'])) {
        $sessionId = intval($_GET['session_id']);
        $sql .= " WHERE s.id = ".$sessionId;
    }

    $sql .= " ORDER BY col$column $direction ";
    $sql .= " LIMIT $from,$number_of_items";
    $res = Database::query($sql);

    $courseUrl = api_get_path(WEB_COURSE_PATH);
    $courses = [];
    while ($course = Database::fetch_array($res)) {
        // Place colour icons in front of courses.
        $showVisualCode = $course['visual_code'] != $course[2] ? Display::label($course['visual_code'], 'info') : null;
        $course[1] = get_course_visibility_icon($course[8]).
            '<a href="'.$courseUrl.$course[9].'/index.php">'.
            $course[1].
            '</a> '.
            $showVisualCode;
        $course[5] = $course[5] == SUBSCRIBE_ALLOWED ? get_lang('Yes') : get_lang('No');
        $course[6] = $course[6] == UNSUBSCRIBE_ALLOWED ? get_lang('Yes') : get_lang('No');
        $row = [
            $course[0],
            $course[1],
            $course[2],
            $course[3],
            $course[4],
            $course[5],
            $course[6],
            $course[7],
        ];
        $courses[] = $row;
    }

    return $courses;
}

/**
 * Return an icon representing the visibility of the course.
 *
 * @param string $visibility
 *
 * @return string
 */
function get_course_visibility_icon($visibility)
{
    $style = 'margin-bottom:0;margin-right:5px;';
    switch ($visibility) {
        case 0:
            return Display::return_icon(
                'bullet_red.png',
                get_lang('Closed - the course is only accessible to the teachers'),
                ['style' => $style]
            );
            break;
        case 1:
            return Display::return_icon(
                'bullet_orange.png',
                get_lang('Private access (access authorized to group members only) access (access authorized to group members only)'),
                ['style' => $style]
            );
            break;
        case 2:
            return Display::return_icon(
                'bullet_green.png',
                get_lang(' Open - access allowed for users registered on the platform'),
                ['style' => $style]
            );
            break;
        case 3:
            return Display::return_icon(
                'bullet_blue.png',
                get_lang('Public - access allowed for the whole world'),
                ['style' => $style]
            );
            break;
        case 4:
            return Display::return_icon(
                'bullet_grey.png',
                get_lang('Hidden - Completely hidden to all users except the administrators'),
                ['style' => $style]
            );
            break;
        default:
            return '';
    }
}

if (isset($_POST['action'])) {
    switch ($_POST['action']) {
        // Delete selected courses
        case 'delete_courses':
            if (!empty($_POST['course'])) {
                $course_codes = $_POST['course'];
                if (count($course_codes) > 0) {
                    foreach ($course_codes as $course_code) {
                        CourseManager::delete_course($course_code);
                    }
                }

                Display::addFlash(Display::return_message(get_lang('Deleted')));
            }
            break;
    }
}
$content = '';
$message = '';
$actions = '';

if (isset($_GET['search']) && $_GET['search'] === 'advanced') {
    // Get all course categories
    $interbreadcrumb[] = [
        'url' => 'index.php',
        'name' => get_lang('Administration'),
    ];
    $interbreadcrumb[] = [
        'url' => 'course_list.php',
        'name' => get_lang('Course list'),
    ];
    $tool_name = get_lang('Search for a course');
    $form = new FormValidator('advanced_course_search', 'get');
    $form->addElement('header', $tool_name);
    $form->addText('keyword_code', get_lang('Course code'), false);
    $form->addText('keyword_title', get_lang('Title'), false);

    // Category code
    $url = api_get_path(WEB_AJAX_PATH).'course.ajax.php?a=search_category';

    $form->addElement(
        'select_ajax',
        'keyword_category',
        get_lang('Category'),
        null,
        [
            'url' => $url,
        ]
    );

    $el = $form->addSelectLanguage('keyword_language', get_lang('Course language'));
    $el->addOption(get_lang('All'), '%');
    $form->addElement('radio', 'keyword_visibility', get_lang("Course access"), get_lang('Public - access allowed for the whole world'), COURSE_VISIBILITY_OPEN_WORLD);
    $form->addElement('radio', 'keyword_visibility', null, get_lang(' Open - access allowed for users registered on the platform'), COURSE_VISIBILITY_OPEN_PLATFORM);
    $form->addElement('radio', 'keyword_visibility', null, get_lang('Private access (access authorized to group members only) access (access authorized to group members only)'), COURSE_VISIBILITY_REGISTERED);
    $form->addElement('radio', 'keyword_visibility', null, get_lang('Closed - the course is only accessible to the teachers'), COURSE_VISIBILITY_CLOSED);
    $form->addElement('radio', 'keyword_visibility', null, get_lang('Hidden - Completely hidden to all users except the administrators'), COURSE_VISIBILITY_HIDDEN);
    $form->addElement('radio', 'keyword_visibility', null, get_lang('All'), '%');
    $form->addElement('radio', 'keyword_subscribe', get_lang('Subscription'), get_lang('Allowed'), 1);
    $form->addElement('radio', 'keyword_subscribe', null, get_lang('This function is only available to trainers'), 0);
    $form->addElement('radio', 'keyword_subscribe', null, get_lang('All'), '%');
    $form->addElement('radio', 'keyword_unsubscribe', get_lang('Unsubscribe'), get_lang('Users are allowed to unsubscribe from this course'), 1);
    $form->addElement('radio', 'keyword_unsubscribe', null, get_lang('NotUsers are allowed to unsubscribe from this course'), 0);
    $form->addElement('radio', 'keyword_unsubscribe', null, get_lang('All'), '%');
    $form->addButtonSearch(get_lang('Search courses'));
    $defaults['keyword_language'] = '%';
    $defaults['keyword_visibility'] = '%';
    $defaults['keyword_subscribe'] = '%';
    $defaults['keyword_unsubscribe'] = '%';
    $form->setDefaults($defaults);
    $content .= $form->returnForm();
} else {
    $interbreadcrumb[] = [
        'url' => 'index.php',
        'name' => get_lang('Administration'),
    ];
    $tool_name = get_lang('Course list');
    if (isset($_GET['delete_course'])) {
        CourseManager::delete_course($_GET['delete_course']);
        Display::addFlash(Display::return_message(get_lang('Deleted')));
    }
    // Create a search-box
    $form = new FormValidator(
        'search_simple',
        'get',
        '',
        '',
        [],
        FormValidator::LAYOUT_INLINE
    );
    $form->addElement(
        'text',
        'keyword',
        null,
        ['id' => 'course-search-keyword', 'aria-label' => get_lang('Search courses')]
    );
    $form->addButtonSearch(get_lang('Search courses'));
    $advanced = '<a class="btn btn-default" href="'.api_get_path(WEB_CODE_PATH).'admin/course_list.php?search=advanced">
        <em class="fa fa-search"></em> '.
        get_lang('Advanced search').'</a>';

    // Create a filter by session
    $sessionFilter = new FormValidator(
        'course_filter',
        'get',
        '',
        '',
        [],
        FormValidator::LAYOUT_INLINE
    );
    $url = api_get_path(WEB_AJAX_PATH).'session.ajax.php?a=search_session';
    $sessionSelect = $sessionFilter->addElement(
        'select_ajax',
        'session_name',
        get_lang('Search coursesBySession'),
        null,
        ['id' => 'session_name', 'url' => $url]
    );

    if (!empty($sessionId)) {
        $sessionInfo = SessionManager::fetch($sessionId);
        $sessionSelect->addOption(
            $sessionInfo['name'],
            $sessionInfo['id'],
            ['selected' => 'selected']
        );
    }

    $courseListUrl = api_get_self();
    $actions1 = Display::url(
        Display::return_icon(
            'new_course.png',
            get_lang('Create a course'),
            [],
            ICON_SIZE_MEDIUM
        ),
        api_get_path(WEB_CODE_PATH).'admin/course_add.php'
    );

    if (api_get_setting('course_validation') === 'true') {
        $actions1 .= Display::url(
            Display::return_icon(
                'course_request_pending.png',
                get_lang('Review incoming course requests'),
                [],
                ICON_SIZE_MEDIUM
            ),
            api_get_path(WEB_CODE_PATH).'admin/course_request_review.php'
        );
    }

    $actions2 = $form->returnForm();
    $actions3 = $sessionFilter->returnForm();
    $actions4 = $advanced;
    $actions4 .= '
    <script>
        $(function() {
            $("#session_name").on("change", function() {
                var sessionId = $(this).val();
                if (!sessionId) {
                    return;
                }
    
                window.location = "'.$courseListUrl.'?session_id="+sessionId;
            });
        });
    </script>';

    $actions = Display::toolbarAction(
        'toolbar',
        [$actions1, $actions2, $actions3, $actions4],
        [2, 4, 3, 3]
    );

    if (isset($_GET['session_id']) && !empty($_GET['session_id'])) {
        // Create a sortable table with the course data filtered by session
        $table = new SortableTable(
            'courses',
            'get_number_of_courses',
            'get_course_data_by_session',
            2
        );
    } else {
        // Create a sortable table with the course data
        $table = new SortableTable(
            'courses',
            'get_number_of_courses',
            'get_course_data',
            2,
            20,
            'ASC',
            'course-list'
        );
    }

    $parameters = [];
    if (isset($_GET['keyword'])) {
        $parameters = ['keyword' => Security::remove_XSS($_GET['keyword'])];
    } elseif (isset($_GET['keyword_code'])) {
        $parameters['keyword_code'] = Security::remove_XSS($_GET['keyword_code']);
        $parameters['keyword_title'] = Security::remove_XSS($_GET['keyword_title']);
        if (isset($_GET['keyword_category'])) {
            $parameters['keyword_category'] = Security::remove_XSS($_GET['keyword_category']);
        }
        $parameters['keyword_language'] = Security::remove_XSS($_GET['keyword_language']);
        $parameters['keyword_visibility'] = Security::remove_XSS($_GET['keyword_visibility']);
        $parameters['keyword_subscribe'] = Security::remove_XSS($_GET['keyword_subscribe']);
        $parameters['keyword_unsubscribe'] = Security::remove_XSS($_GET['keyword_unsubscribe']);
    }

    $table->set_additional_parameters($parameters);

    $table->set_header(0, '', false, 'width="8px"');
    $table->set_header(1, get_lang('Title'), true, null, ['class' => 'title']);
    $table->set_header(2, get_lang('Course code'));
    $table->set_header(3, get_lang('Language'), false, 'width="70px"');
    $table->set_header(4, get_lang('Category'));
    $table->set_header(5, get_lang('Registr. allowed'), true, 'width="60px"');
    $table->set_header(6, get_lang('UnsubscribeAllowed'), false, 'width="50px"');
    $table->set_header(
        7,
        get_lang('Action'),
        false,
        null,
        ['class' => 'td_actions']
    );
    $table->set_form_actions(
        ['delete_courses' => get_lang('Delete selected course(s)')],
        'course'
    );
    $content .= $table->return_table();
}

$tpl = new Template($tool_name);
$tpl->assign('actions', $actions);
$tpl->assign('message', $message);
$tpl->assign('content', $content);
$tpl->display_one_col_template();
