Finding question / answer node containers more dinamically

stable.user.js

@@ -351,6 +351,7 @@
     getQuizData()
       .then(readQuestions => {
         if (readQuestions.length === 0) {
+          warn('readQuestions length is zero, no questions found on page!')
           ShowMessage(
             texts.unableToParseTestQuestion,
 
@@ -401,20 +402,68 @@
       })
   }
 
+  const questionNodeVariants = {
+    formFirst: {
+      criteria: () => {
+        const questionNodes = Array.from(
+          document.getElementsByTagName('form')[0].childNodes[0].childNodes
+        )
+        // test: e2c01ff4-d97a-4ab9-8f7f-e28812541097
+        const notOnlyTextNodes = questionNodes.every(node => {
+          return node.tagName !== undefined
+        })
+        return notOnlyTextNodes && questionNodes.length > 0
+      },
+      getter: () => {
+        return Array.from(
+          document.getElementsByTagName('form')[0].childNodes[0].childNodes
+        )
+      },
+    },
+    formSecond: {
+      criteria: () => {
+        const questionNodes = Array.from(
+          document.getElementsByTagName('form')[1].childNodes[0].childNodes
+        )
+        return questionNodes.length > 0
+      },
+      getter: () => {
+        return Array.from(
+          document.getElementsByTagName('form')[1].childNodes[0].childNodes
+        )
+      },
+    },
+  }
+
+  function getQuestionNodes() {
+    try {
+      let questionNodes
+      Object.keys(questionNodeVariants).some(key => {
+        const variant = questionNodeVariants[key]
+        if (variant.criteria()) {
+          questionNodes = variant.getter()
+          if (questionNodes.length === 0) {
+            warn(
+              `question nodes ${key} criteria was true, but result is an empty array!`
+            )
+          } else {
+            return true
+          }
+        }
+      })
+      return questionNodes
+    } catch (e) {
+      warn('Error in getQuestionNodes')
+      warn(e)
+    }
+  }
+
   function getQuizData() {
     return new Promise(resolve => {
       // TODO: dropdown in question
       // TODO: get possible answers too
       const promises = []
-      let questionNodes = Array.from(
+      const questionNodes = getQuestionNodes()
-        document.getElementsByTagName('form')[0].childNodes[0].childNodes
-      )
-
-      if (questionNodes.length === 0) {
-        questionNodes = Array.from(
-          document.getElementsByTagName('form')[1].childNodes[0].childNodes
-        )
-      }
 
       let i = 0
       while (
@@ -667,17 +716,43 @@
 
   // : Result page processing functions {{{
 
+  const resultNodeVariants = questionNodeVariants
+
+  function getResultNodes() {
+    try {
+      let resultNodes
+      Object.keys(resultNodeVariants).some(key => {
+        const variant = resultNodeVariants[key]
+        if (variant.criteria()) {
+          resultNodes = variant.getter()
+          if (resultNodes.length === 0) {
+            warn(
+              `result nodes ${key} criteria was true, but result is an empty array!`
+            )
+          } else {
+            return true
+          }
+        }
+      })
+      return resultNodes
+    } catch (e) {
+      warn('Error in getResultNodes')
+      warn(e)
+    }
+  }
+
   function getQuiz() {
     return new Promise(resolve => {
       const promises = []
-      let questionNodes = Array.from(
+      const questionNodes = getResultNodes()
-        document.getElementsByTagName('form')[0].childNodes[0].childNodes
+      // let questionNodes = Array.from(
-      )
+      //   document.getElementsByTagName('form')[0].childNodes[0].childNodes
-      if (questionNodes.length === 0) {
+      // )
-        questionNodes = Array.from(
+      // if (questionNodes.length === 0) {
-          document.getElementsByTagName('form')[1].childNodes[0].childNodes
+      //   questionNodes = Array.from(
-        )
+      //     document.getElementsByTagName('form')[1].childNodes[0].childNodes
-      }
+      //   )
+      // }
 
       let i = 0
       while (i < questionNodes.length && questionNodes[i].tagName === 'DIV') {