<?php
require_once('../../config.php');
require_once($CFG->libdir . '/adminlib.php');
require_once($CFG->libdir . '/gradelib.php');
require_once($CFG->libdir . '/tablelib.php');
require_once($CFG->libdir . '/formslib.php');
require_once($CFG->dirroot . '/user/selector/lib.php');

// Set up the page context and other configurations
admin_externalpage_setup('report_usergrades', '', null, '', array('capability' => 'report/usergrades:view'));

class user_selector extends user_selector_base
{

    public function find_users($search)
    {
        global $DB;

        // Define the fields you want to select.
        $fields = 'id, firstname, lastname, email';

        // Create an SQL query to find users based on the search criteria.
        $sql = "SELECT $fields
                  FROM {user}
                 WHERE CONCAT(firstname, ' ', lastname) LIKE ? OR email LIKE ?";

        // Execute the SQL query and retrieve the users.
        $users = $DB->get_records_sql($sql, array('%' . $search . '%', '%' . $search . '%'));

        // Format the users into a format expected by the user selector.
        $options = [];
        foreach ($users as $user) {
            $options[$user->id] = $user->firstname . ' ' . $user->lastname . ' (' . $user->email . ')';
        }

        return array(get_string('users') => $options);
    }
}

/**
 * Form class for user selection
 */
class usergrades_form extends moodleform
{
    public function definition()
    {
        $mform = $this->_form;

        // User selector
        $user_selector = new user_selector('userid', array('multiselect' => false));
        $users = $user_selector->find_users('');

        $mform->addElement('select', 'userid', get_string('selectuser', 'report_usergrades'), $users[get_string('users')]);

        // Add form action buttons
        $this->add_action_buttons(false, get_string('showgrades', 'report_usergrades'));
    }
}

// Instantiate the form
$mform = new usergrades_form();
echo $OUTPUT->header();
echo $OUTPUT->heading(get_string('usergradesreport', 'report_usergrades'));

// Form processing and displaying is done here
if ($mform->is_cancelled()) {
    // Handle form cancellation, if necessary
    redirect(new moodle_url('/admin/report.php'));
} else if ($data = $mform->get_data()) {
    $userid = $data->userid;

    // Fetch and display user grades if a user is selected
    if (!empty($userid)) {
        $user = $DB->get_record('user', array('id' => $userid), '*', MUST_EXIST);
        $courses = enrol_get_users_courses($user->id, true);

        $table = new flexible_table('user-grades-report');
        $table->define_baseurl($CFG->wwwroot . '/report/usergrades/index.php');
        $table->define_columns(array('course', 'activity', 'grade'));
        $table->define_headers(array(get_string('course'), get_string('activity'), get_string('grade', 'report_usergrades')));

        $table->setup();

        foreach ($courses as $course) {
            $grade_items = grade_item::fetch_all(array('courseid' => $course->id));

            foreach ($grade_items as $item) {
                $grade = grade_grade::fetch(array('itemid' => $item->id, 'userid' => $user->id));
                $gradename = $item->get_name();
                $grade_display = $grade ? $grade->finalgrade . ' / ' . $grade->rawgrademax : '-';

                $table->add_data(array(format_string($course->fullname), format_string($gradename), $grade_display));
            }
        }

        $table->finish_output();
    } else {
        echo $OUTPUT->notification(get_string('nouserselected', 'report_usergrades'), 'notifyproblem');
    }
} else {
    // Display form if no data is submitted
    $mform->display();
}

echo $OUTPUT->footer();