diff --git a/classes/text_filter.php b/classes/text_filter.php
new file mode 100644
index 0000000..5c20ebe
--- /dev/null
+++ b/classes/text_filter.php
@@ -0,0 +1,189 @@
+.
+
+namespace filter_embedquestion;
+
+use filter_embedquestion\embed_id;
+use filter_embedquestion\embed_location;
+use filter_embedquestion\output\embed_iframe;
+use filter_embedquestion\output\error_message;
+use filter_embedquestion\question_options;
+use filter_embedquestion\token;
+use filter_embedquestion\utils;
+
+/**
+ * A Moodle text filter to embed questions from the bank in content.
+ *
+ * @package filter_embedquestion
+ * @copyright 2018 The Open University
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class text_filter extends \moodle_text_filter {
+ /**
+ * @var string Closing part of the embed token wrapper.
+ */
+ const STRING_PREFIX = '{Q{';
+ /**
+ * @var string Closing part of the embed token wrapper.
+ */
+ const STRING_SUFFIX = '}Q}';
+
+ /**
+ * @var \filter_embedquestion\output\renderer the renderer.
+ */
+ protected $renderer;
+
+ /**
+ * @var int the course id, derived from $this->context.
+ */
+ protected $courseid;
+
+ /**
+ * @var moodle_page page object
+ */
+ protected $page;
+
+ public function setup($page, $context) {
+ $this->page = $page;
+ }
+
+ /**
+ * Get the regexp needed to extract embed codes from within some text.
+ *
+ * @return string the regular expression.
+ */
+ public static function get_filter_regexp(): string {
+ return '~' . preg_quote(self::STRING_PREFIX, '~') .
+ '((?:(?!' . preg_quote(self::STRING_SUFFIX, '~') . ').)*)' .
+ preg_quote(self::STRING_SUFFIX, '~') . '~';
+ }
+
+ public function filter($text, array $options = []) {
+ return preg_replace_callback(self::get_filter_regexp(),
+ [$this, 'embed_question_callback'], $text);
+ }
+
+ /**
+ * For use by the preg_replace_callback call above.
+ *
+ * @param array $matches the parts matched by the regular expression.
+ *
+ * @return string the replacement string.
+ */
+ public function embed_question_callback(array $matches): string {
+ return $this->embed_question($matches[1]);
+ }
+
+ /**
+ * Process the bit of the input for embedding one question.
+ *
+ * @param string $embedcode the contents of the {Q{...}Q} delimiters.
+ *
+ * @return string HTML code for the iframe to display the question.
+ */
+ public function embed_question(string $embedcode): string {
+ if ($this->renderer === null) {
+ $this->renderer = $this->page->get_renderer('filter_embedquestion');
+ }
+ if ($this->courseid === null) {
+ $this->courseid = utils::get_relevant_courseid($this->context);
+ }
+ if (isguestuser()) {
+ return $this->display_error('noguests');
+ }
+
+ list($embedid, $params) = self::parse_embed_code($embedcode);
+ if ($embedid === null) {
+ return $this->display_error('invalidtoken');
+ }
+
+ $options = new question_options();
+ $options->set_from_filter_options($params);
+
+ if (!$options->iframedescription) {
+ $options->iframedescription = utils::make_unique_iframe_description();
+ }
+
+ $embedlocation = embed_location::make_from_page($this->page);
+
+ $showquestionurl = utils::get_show_url($embedid, $embedlocation, $options);
+ return $this->renderer->render(new embed_iframe($showquestionurl, $options->iframedescription));
+ }
+
+ /**
+ * Display an error since the question cannot be displayed.
+ *
+ * @param string $string the string to use for the message.
+ * @param array|null $a any values needed by the strings.
+ *
+ * @return string HTML for the error.
+ */
+ protected function display_error(string $string, array $a = null): string {
+ return $this->renderer->render(new error_message(
+ get_string($string, 'filter_embedquestion', $a)));
+ }
+
+ /**
+ * Parse an embed code, validate the token, and return the idnumbers and any options.
+ * @param string $embedcode the embed code.
+ * @return array an array with two elements: $embedid and $params.
+ * If the code is invalid, all elements are null.
+ */
+ public static function parse_embed_code(string $embedcode): array {
+ $parts = explode('|', htmlspecialchars_decode($embedcode));
+
+ if (count($parts) < 2) {
+ return [null, null];
+ }
+
+ $questioninfo = array_shift($parts);
+ $token = array_pop($parts);
+
+ $embedid = embed_id::create_from_string($questioninfo);
+ if ($embedid === null) {
+ return [null, null];
+ }
+
+ if (!token::is_authorized_secret_token($token, $embedid)) {
+ return [null, null];
+ }
+
+ $params = self::parse_options($parts);
+ if (!is_array($params)) {
+ return [null, null];
+ }
+
+ return [$embedid, $params];
+ }
+
+ /**
+ * Process the options, verifying that they are all of the form name=value.
+ *
+ * @param array $parts the individual 'name=options' strings.
+ * @return array|null the parsed options, or false if they were malformed.
+ */
+ public static function parse_options(array $parts): ?array {
+ $params = [];
+ foreach ($parts as $part) {
+ if (strpos($part, '=') === false) {
+ return null;
+ }
+ list($name, $value) = explode('=', $part);
+ $params[$name] = $value;
+ }
+ return $params;
+ }
+}
diff --git a/filter.php b/filter.php
index 7bd1ea6..26fb12c 100644
--- a/filter.php
+++ b/filter.php
@@ -14,174 +14,15 @@
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see .
-use filter_embedquestion\embed_id;
-use filter_embedquestion\embed_location;
-use filter_embedquestion\output\embed_iframe;
-use filter_embedquestion\output\error_message;
-use filter_embedquestion\question_options;
-use filter_embedquestion\token;
-use filter_embedquestion\utils;
-
/**
* A Moodle text filter to embed questions from the bank in content.
*
- * @package filter_embedquestion
- * @copyright 2018 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package filter_embedquestion
+ * @copyright 2024 onwards University College London {@link https://www.ucl.ac.uk/}
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @author Leon Stringer
*/
-class filter_embedquestion extends moodle_text_filter {
- /**
- * @var string Closing part of the embed token wrapper.
- */
- const STRING_PREFIX = '{Q{';
- /**
- * @var string Closing part of the embed token wrapper.
- */
- const STRING_SUFFIX = '}Q}';
-
- /**
- * @var \filter_embedquestion\output\renderer the renderer.
- */
- protected $renderer;
-
- /**
- * @var int the course id, derived from $this->context.
- */
- protected $courseid;
-
- /**
- * @var moodle_page page object
- */
- protected $page;
-
- public function setup($page, $context) {
- $this->page = $page;
- }
-
- /**
- * Get the regexp needed to extract embed codes from within some text.
- *
- * @return string the regular expression.
- */
- public static function get_filter_regexp(): string {
- return '~' . preg_quote(self::STRING_PREFIX, '~') .
- '((?:(?!' . preg_quote(self::STRING_SUFFIX, '~') . ').)*)' .
- preg_quote(self::STRING_SUFFIX, '~') . '~';
- }
-
- public function filter($text, array $options = []) {
- return preg_replace_callback(self::get_filter_regexp(),
- [$this, 'embed_question_callback'], $text);
- }
-
- /**
- * For use by the preg_replace_callback call above.
- *
- * @param array $matches the parts matched by the regular expression.
- *
- * @return string the replacement string.
- */
- public function embed_question_callback(array $matches): string {
- return $this->embed_question($matches[1]);
- }
-
- /**
- * Process the bit of the input for embedding one question.
- *
- * @param string $embedcode the contents of the {Q{...}Q} delimiters.
- *
- * @return string HTML code for the iframe to display the question.
- */
- public function embed_question(string $embedcode): string {
- if ($this->renderer === null) {
- $this->renderer = $this->page->get_renderer('filter_embedquestion');
- }
- if ($this->courseid === null) {
- $this->courseid = utils::get_relevant_courseid($this->context);
- }
- if (isguestuser()) {
- return $this->display_error('noguests');
- }
-
- list($embedid, $params) = self::parse_embed_code($embedcode);
- if ($embedid === null) {
- return $this->display_error('invalidtoken');
- }
-
- $options = new question_options();
- $options->set_from_filter_options($params);
-
- if (!$options->iframedescription) {
- $options->iframedescription = utils::make_unique_iframe_description();
- }
-
- $embedlocation = embed_location::make_from_page($this->page);
-
- $showquestionurl = utils::get_show_url($embedid, $embedlocation, $options);
- return $this->renderer->render(new embed_iframe($showquestionurl, $options->iframedescription));
- }
-
- /**
- * Display an error since the question cannot be displayed.
- *
- * @param string $string the string to use for the message.
- * @param array|null $a any values needed by the strings.
- *
- * @return string HTML for the error.
- */
- protected function display_error(string $string, array $a = null): string {
- return $this->renderer->render(new error_message(
- get_string($string, 'filter_embedquestion', $a)));
- }
-
- /**
- * Parse an embed code, validate the token, and return the idnumbers and any options.
- * @param string $embedcode the embed code.
- * @return array an array with two elements: $embedid and $params.
- * If the code is invalid, all elements are null.
- */
- public static function parse_embed_code(string $embedcode): array {
- $parts = explode('|', htmlspecialchars_decode($embedcode));
-
- if (count($parts) < 2) {
- return [null, null];
- }
-
- $questioninfo = array_shift($parts);
- $token = array_pop($parts);
-
- $embedid = embed_id::create_from_string($questioninfo);
- if ($embedid === null) {
- return [null, null];
- }
-
- if (!token::is_authorized_secret_token($token, $embedid)) {
- return [null, null];
- }
-
- $params = self::parse_options($parts);
- if (!is_array($params)) {
- return [null, null];
- }
- return [$embedid, $params];
- }
+defined('MOODLE_INTERNAL') || die();
- /**
- * Process the options, verifying that they are all of the form name=value.
- *
- * @param array $parts the individual 'name=options' strings.
- * @return array|null the parsed options, or false if they were malformed.
- */
- public static function parse_options(array $parts): ?array {
- $params = [];
- foreach ($parts as $part) {
- if (strpos($part, '=') === false) {
- return null;
- }
- list($name, $value) = explode('=', $part);
- $params[$name] = $value;
- }
- return $params;
- }
-}
+class_alias(\filter_embedquestion\text_filter::class, \filter_embedquestion::class);
diff --git a/tests/attempt_test.php b/tests/attempt_test.php
index de2fe8c..6412b8d 100644
--- a/tests/attempt_test.php
+++ b/tests/attempt_test.php
@@ -275,7 +275,7 @@ public function test_question_rendering(): void {
$expectedregex = '~Question [^<]+' .
'
Not complete
Marked out of 1.00
' .
'
' .
+ '
]*>Edit question