Display formula using Ajax

7 files changed, 70 insertions, 50 deletions

diff --git a/ajax.php b/ajax.php
index 156db22..9231012 100644
--- a/ajax.php
+++ b/ajax.php
@@ -38,18 +38,30 @@ if (!confirm_sesskey()) {
 try {
     $vars = explode(',', $vars);
     if (empty($expr)) {
-        $texexp = '';
+        $texexp = ' ';
     } else {
         $exp = $p->parse($expr, $vars);
         $texexp = $exp->tex();
     }
 } catch (Exception $e) {
-    $texexp = '';
+    $texexp = ' ';
 }
-if ($CFG->qtype_algebra_texdelimiters == 'old') {
-    $texexp = '$$' . $texexp . '$$';
-} else {
-    $texexp = '\\[' . $texexp . '\\]';
+
+$delimiters = $CFG->qtype_algebra_texdelimiters;
+switch($delimiters) {
+    case 'old':
+        $texexp = '$$' . $texexp . '$$';
+        break;
+    case 'new':
+        $texexp = '\\[' . $texexp . '\\]';
+        break;
+    case 'simple';
+        $texexp = '$' . $texexp . '$';
+        break;
+    case 'inline':
+        $texexp = '\\(' . $texexp . '\\)';
+        break;
 }
+
 header('Content-Type: application/json; charset: utf-8');
 echo json_encode($texexp);
diff --git a/displayformula.php b/displayformula.php
index 9693af3..6ba12fb 100644
--- a/displayformula.php
+++ b/displayformula.php
@@ -48,11 +48,22 @@ try {
         $texexp = '';
     } else {
         $exp = $p->parse($m[2], $vars);
-        if ($CFG->qtype_algebra_texdelimiters == 'old') {
-            $texexp = '$$'.$exp->tex().'$$';
-        } else {
-            $texexp = '\['.$exp->tex().'\]';
+        $texexp = $exp->tex();
+        switch($CFG->qtype_algebra_texdelimiters) {
+            case 'old':
+                $texexp = '$$' . $texexp . '$$';
+                break;
+            case 'new':
+                $texexp = '\\[' . $texexp . '\\]';
+                break;
+            case 'simple';
+                $texexp = '$' . $texexp . '$';
+                break;
+            case 'inline':
+                $texexp = '\\(' . $texexp . '\\)';
+                break;
         }
+
     }
 } catch (Exception $e) {
     $validanswer = false;
diff --git a/lang/en/qtype_algebra.php b/lang/en/qtype_algebra.php
index 4006858..8c8ed2e 100644
--- a/lang/en/qtype_algebra.php
+++ b/lang/en/qtype_algebra.php
@@ -142,6 +142,8 @@ $string['uri'] = 'uri of SAGE server';
 $string['texdelimiters'] = 'Delimiters for TeX expressions';
 $string['dollars'] = '$$...$$';
 $string['brackets'] = '\[...\]';
+$string['braces'] = '\\(...\\)';
+$string['dollar'] = '$...$';
 $string['invalidanswer'] = 'Invalid or unrecongnized answer';
 $string['multiplyoperator'] = 'TeX operator for multiplication';
 $string['times'] = '\\times';
diff --git a/question.php b/question.php
index 52f8392..dffbeef 100644
--- a/question.php
+++ b/question.php
@@ -126,14 +126,15 @@ class qtype_algebra_question extends question_graded_by_strategy
      * @param $expr expression which will be parsed
      * @return top term of the parse tree or a string if an exception is thrown
      */
-    public function formated_expression($text) {
+    public function formated_expression($text, $vars = null) {
         global $CFG;
-
-        // Create an array of variable names for the parser from the question if defined.
-        $varnames = array();
-        if (isset($this->variables)) {
-            foreach ($this->variables as $var) {
-                $varnames[] = $var->name;
+        if ($vars == null) {
+            // Create an array of variable names for the parser from the question if defined.
+            $vars = array();
+            if (isset($this->variables)) {
+                foreach ($this->variables as $var) {
+                    $vars[] = $var->name;
+                }
             }
         }
         // We now assume that we have a string to parse. Create a parser instance to
@@ -142,16 +143,24 @@ class qtype_algebra_question extends question_graded_by_strategy
         // Perform the actual parsing inside a try-catch block so that any exceptions
         // can be caught and converted into errors.
         try {
-            $exp = $p->parse($text, $varnames);
-            if ($CFG->qtype_algebra_texdelimiters == 'old') {
-                return '$$'.$exp->tex().'$$';
-            } else {
-                return '\['.$exp->tex().'\]';
-            }
-
+            $exp = $p->parse($text, $vars);
+            $texexp = $exp->tex();
         } catch (Exception $e) {
-            return '';
+            $texexp = ' ';
         }
+
+        $delimiters = $CFG->qtype_algebra_texdelimiters;
+        switch($delimiters) {
+            case 'old':
+                return '$$' . $texexp . '$$';
+            case 'new':
+                return '\\[' . $texexp . '\\]';
+            case 'simple';
+                return '$' . $texexp . '$';
+            case 'inline':
+                return '\\(' . $texexp . '\\)';
+        }
+
     }
 
     public function is_same_response(array $prevresponse, array $newresponse) {
diff --git a/renderer.php b/renderer.php
index ec3d57e..e19ae11 100644
--- a/renderer.php
+++ b/renderer.php
@@ -76,14 +76,14 @@ class qtype_algebra_renderer extends qtype_renderer {
         }
         
         // Create an array of variable names to use when displaying the function entered.
-        $varnames = array();
+        $vars = array();
         if ($question and isset($question->variables)) {
             $variables = $question->variables;
             foreach ($question->variables as $var) {
-                $varnames[] = $var->name;
+                $vars[] = $var->name;
             }
         }
-        $varnames = implode(',', $varnames);
+        $varnames = implode(',', $vars);
 
         $questiontext = $question->format_questiontext($qa);
 
@@ -142,25 +142,9 @@ class qtype_algebra_renderer extends qtype_renderer {
                 'style' => 'display:none',
                 )
             );
-            $p = new qtype_algebra_parser;
-            try {
-                $vars = explode(',', $varnames);
-                if (empty($currentanswer)) {
-                    $texexp = '';
-                } else {
-                    $exp = $p->parse($currentanswer, $vars);
-                    $texexp = $exp->tex();
-               }
-            } catch (Exception $e) {
-               $texexp = '';
-            }
-            if ($CFG->qtype_algebra_texdelimiters == 'old') {
-                $texexp = '$$' . $texexp . '$$';
-            } else {
-                $texexp = '\\[' . $texexp . '\\]';
-            }
-            $display = $question->format_text("<span class=\"filter_mathjaxloader_equation\">" . $texexp ."</span>",
-                                    1 ,$qa, 'question', 'questiontext', $question->id);
+
+            $display = $question->format_text("<span class=\"filter_mathjaxloader_equation\">" . $question->formated_expression($currentanswer, $vars) ."</span>",
+                                    FORMAT_MOODLE ,$qa, 'question', 'questiontext', $question->id);
             $result .= html_writer::tag('div', $display ,array(
                 'type' => 'text',
                 'name' => $nameprefix . '_display',
diff --git a/settings.php b/settings.php
index 1c6fa30..485a723 100644
--- a/settings.php
+++ b/settings.php
@@ -45,7 +45,9 @@ if ($ADMIN->fulltree) {
             new lang_string('texdelimiters', 'qtype_algebra'),
             '', 'old',
             array('old' => new lang_string('dollars', 'qtype_algebra'),
-                  'new' => new lang_string('brackets', 'qtype_algebra')
+                  'simple' => new lang_string('dollar', 'qtype_algebra'),
+                  'new' => new lang_string('brackets', 'qtype_algebra'),
+                  'inline' => new lang_string('braces', 'qtype_algebra'),
             )));
     // TeX operator for multiplication.
     $settings->add(new admin_setting_configselect('qtype_algebra/multiplyoperator',
diff --git a/version.php b/version.php
index 1db1702..a0cbc70 100644
--- a/version.php
+++ b/version.php
@@ -23,8 +23,8 @@
 defined('MOODLE_INTERNAL') || die();
 
 $plugin->component = 'qtype_algebra';
-$plugin->version   = 2018020100;
+$plugin->version   = 2018020400;
 
 $plugin->requires  = 2013050100;
-$plugin->release   = '1.6 for Moodle 2.8, ... 3.5';
+$plugin->release   = '1.7 for Moodle 2.8, ... 3.5';
 $plugin->maturity  = MATURITY_STABLE;