Ajax dynamic formula display

1 files changed, 55 insertions, 0 deletions

diff --git a/ajax.php b/ajax.php
new file mode 100644
index 0000000..156db22
--- /dev/null
+++ b/ajax.php
@@ -0,0 +1,55 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle 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 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * @package    qtype_algebra
+ * @copyright  2018 Jean-Michel Vedrine
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+define('AJAX_SCRIPT', true);
+
+require_once(__DIR__ . '/../../../config.php');
+require_once(__DIR__ . '/parser.php');
+
+$p = new qtype_algebra_parser;
+
+$vars  = required_param('vars', PARAM_RAW);
+$expr  = required_param('expr', PARAM_RAW);
+/*
+if (!confirm_sesskey()) {
+    header('HTTP/1.1 403 Forbidden');
+    die();
+}
+*/
+try {
+    $vars = explode(',', $vars);
+    if (empty($expr)) {
+        $texexp = '';
+    } else {
+        $exp = $p->parse($expr, $vars);
+        $texexp = $exp->tex();
+    }
+} catch (Exception $e) {
+    $texexp = '';
+}
+if ($CFG->qtype_algebra_texdelimiters == 'old') {
+    $texexp = '$$' . $texexp . '$$';
+} else {
+    $texexp = '\\[' . $texexp . '\\]';
+}
+header('Content-Type: application/json; charset: utf-8');
+echo json_encode($texexp);