ui: fix submission language selection

packages/ui-default/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@hydrooj/ui-default",
-  "version": "4.33.6",
+  "version": "4.33.7",
   "author": "undefined <i@undefined.moe>",
   "license": "AGPL-3.0",
   "main": "hydro.js",

packages/ui-default/pages/problem_submit.page.js

@@ -38,27 +38,35 @@ const page = new NamedPage(['problem_submit', 'contest_detail_problem_submit', '
     }
   }
   setOptions($('#codelang-main-select'), main);
-  if (Object.keys(main).length === 1) $('#codelang-main-container').hide();
 
+  let isFallback = false;
   const current = $('[name="lang"]').val();
   if (current.includes('.')) {
     const [m] = current.split('.');
-    $('#codelang-main-select').val(m);
-    const fallback = onChangeMain.call({ value: m }, false);
-    $('#codelang-sub-select').val(current);
-    if (fallback && !$('#codelang-sub-select').val()) {
-      $('#codelang-sub-select').val(fallback);
-      $('[name="lang"]').val(fallback);
-    }
-  } else {
+    if (main[m]) {
+      $('#codelang-main-select').val(m);
+      const fallback = onChangeMain.call({ value: m }, false);
+      $('#codelang-sub-select').val(current);
+      if (fallback && !$('#codelang-sub-select').val()) {
+        $('#codelang-sub-select').val(fallback);
+        $('[name="lang"]').val(fallback);
+      }
+    } else isFallback = true;
+  } else if (main[current]) {
     $('#codelang-main-select').val(current);
     onChangeMain.call({ value: $('#codelang-main-select').val() }, false);
+  } else isFallback = true;
+
+  if (isFallback) {
+    $('#codelang-main-select').val(Object.keys(main)[0]);
+    onChangeMain.call({ value: Object.keys(main)[0] }, false);
   }
 
   $('#codelang-main-select').on('change', onChangeMain);
   $('#codelang-sub-select').on('change', function () {
     $('[name="lang"]').val(this.value);
   });
+  if (Object.keys(main).length === 1) $('#codelang-main-container').hide();
 });
 
 export default page;

packages/ui-default/templates/problem_submit.html

@@ -18,7 +18,7 @@
               }) }}
           </div>
           <div class="row nojs--hide">
-            <div class="medium-5 columns form__item end">
+            <div class="medium-5 columns form__item end" id="codelang-main-container">
               <label>
                 {{ _('Code language') }}
                 <div name="form_item_lang" class="select-container">