Find attempted questions by difficulty (seanprashad#64)

* Find attempted questions by difficulty

* removed unused import statement

Author: juhitiwari

src/components/Table/index.js

@@ -39,6 +39,17 @@ const Table = () => {
     checkedList = newCheckedList;
     window.localStorage.setItem('checked', JSON.stringify(checkedList));
   }
+  const data = React.useMemo(() => questions, []);
+  /* Get a list of all checked questions in the form of a dictionary keys as question difficulty */
+  const checkedQuestionsByDifficulty = { Easy: 0, Hard: 0, Medium: 0 };
+  for (let i = 0; i < checkedList.length; i += 1) {
+    if (checkedList[i]) {
+      checkedQuestionsByDifficulty[data[i].difficulty] += 1;
+    }
+  }
+  const [checkQuestionsDict, setcheckQuestionsDict] = useState(
+    checkedQuestionsByDifficulty,
+  );
 
   const [checked, setChecked] = useState(checkedList);
 
@@ -54,7 +65,8 @@ const Table = () => {
     window.localStorage.setItem('showPatterns', JSON.stringify(showPatterns));
   }, [showPatterns]);
 
-  const data = React.useMemo(() => questions, []);
+  /*To view the number of question solved by difficulty*/
+  console.log(checkQuestionsDict);
 
   const defaultColumn = React.useMemo(
     () => ({
@@ -81,6 +93,22 @@ const Table = () => {
                     checked[cellInfo.row.original.id] = !checked[
                       cellInfo.row.original.id
                     ];
+                    /*increment or decrement question count for the correct difficulty from the checkbox */
+                    if (checked[cellInfo.row.original.id]) {
+                      setcheckQuestionsDict(prevState => ({
+                        ...prevState,
+                        [cellInfo.row.original.difficulty]:
+                          prevState[cellInfo.row.original.difficulty] + 1,
+                      }));
+                    } else {
+                      setcheckQuestionsDict(prevState => ({
+                        ...prevState,
+                        [cellInfo.row.original.difficulty]:
+                          prevState[cellInfo.row.original.difficulty] === 0
+                            ? 0
+                            : prevState[cellInfo.row.original.difficulty] - 1,
+                      }));
+                    }
                     setChecked([...checked]);
                   }}
                 />