Resolve "Language select uses English as default language (and not browser language)"

Closes #856 (closed)

aleksis/core/frontend/components/app/LanguageForm.vue

@@ -33,17 +33,33 @@ export default {
       type: Array,
       required: true,
     },
+    defaultLanguage: {
+      type: Object,
+      required: true,
+    },
   },
   methods: {
     setLanguage: function (languageOption) {
       document.cookie = languageOption.cookie;
       this.$i18n.locale = languageOption.code;
       this.$vuetify.lang.current = languageOption.code;
+      this.language = languageOption;
     },
     nameForMenu: function (item) {
       return `${item.nameLocal} (${item.code})`;
     },
   },
+  mounted() {
+    if (
+      this.availableLanguages.filter((lang) => lang.code === this.$i18n.locale)
+        .length === 0
+    ) {
+      console.warn(
+        `Unsupported language ${this.$i18n.locale} selected, defaulting to ${this.defaultLanguage.code}`
+      );
+      this.setLanguage(this.defaultLanguage);
+    }
+  },
   name: "LanguageForm",
 };
 </script>