Solved the exercise counter bug

src/exams/Reading.tsx

@@ -1,4 +1,4 @@
-import {ReadingExam, UserSolution} from "@/interfaces/exam";
+import {MultipleChoiceExercise, ReadingExam, UserSolution} from "@/interfaces/exam";
 import {Fragment, useEffect, useState} from "react";
 import Icon from "@mdi/react";
 import {mdiArrowRight, mdiNotebook} from "@mdi/js";
@@ -85,12 +85,13 @@ export default function Reading({exam, showSolutions = false, onFinish}: Props)
 	const [currentQuestionIndex, setCurrentQuestionIndex] = useState(0);
 	const [showTextModal, setShowTextModal] = useState(false);
 	const [showBlankModal, setShowBlankModal] = useState(false);
+	const [multipleChoicesDone, setMultipleChoicesDone] = useState<{id: string; amount: number}[]>([]);
 
 	const {userSolutions, setUserSolutions} = useExamStore((state) => state);
 	const {hasExamEnded, setHasExamEnded} = useExamStore((state) => state);
 	const {partIndex, setPartIndex} = useExamStore((state) => state);
 	const {exerciseIndex, setExerciseIndex} = useExamStore((state) => state);
-	const setStoreQuestionIndex = useExamStore((state) => state.setQuestionIndex);
+	const [storeQuestionIndex, setStoreQuestionIndex] = useExamStore((state) => [state.questionIndex, state.setQuestionIndex]);
 
 	const scrollToTop = () => Array.from(document.getElementsByTagName("body")).forEach((body) => body.scrollTo(0, 0));
 
@@ -98,6 +99,21 @@ export default function Reading({exam, showSolutions = false, onFinish}: Props)
 		if (showSolutions) setExerciseIndex(-1);
 	}, [setExerciseIndex, showSolutions]);
 
+	useEffect(() => {
+		const previousParts = exam.parts.filter((_, index) => index < partIndex);
+		let previousMultipleChoice = previousParts.flatMap((x) => x.exercises).filter((x) => x.type === "multipleChoice") as MultipleChoiceExercise[];
+
+		if (partIndex > -1 && exerciseIndex > -1) {
+			const previousPartExercises = exam.parts[partIndex].exercises.filter((_, index) => index < exerciseIndex);
+			const partMultipleChoice = previousPartExercises.filter((x) => x.type === "multipleChoice") as MultipleChoiceExercise[];
+
+			previousMultipleChoice = [...previousMultipleChoice, ...partMultipleChoice];
+		}
+
+		setMultipleChoicesDone(previousMultipleChoice.map((x) => ({id: x.id, amount: x.questions.length - 1})));
+		// eslint-disable-next-line react-hooks/exhaustive-deps
+	}, []);
+
 	useEffect(() => {
 		const listener = (e: KeyboardEvent) => {
 			if (e.key === "F3" || ((e.ctrlKey || e.metaKey) && e.key === "f")) {
@@ -136,7 +152,10 @@ export default function Reading({exam, showSolutions = false, onFinish}: Props)
 		if (solution) {
 			setUserSolutions([...userSolutions.filter((x) => x.exercise !== solution.exercise), {...solution, module: "reading", exam: exam.id}]);
 		}
-		setQuestionIndex((prev) => prev + currentQuestionIndex);
+		if (storeQuestionIndex > 0) {
+			const exercise = getExercise();
+			setMultipleChoicesDone((prev) => [...prev.filter((x) => x.id !== exercise.id), {id: exercise.id, amount: storeQuestionIndex}]);
+		}
 		setStoreQuestionIndex(0);
 
 		if (exerciseIndex + 1 < exam.parts[partIndex].exercises.length && !hasExamEnded) {
@@ -189,6 +208,31 @@ export default function Reading({exam, showSolutions = false, onFinish}: Props)
 		};
 	};
 
+	useEffect(() => {
+		if (partIndex > -1 && exerciseIndex > -1) {
+			const exercise = getExercise();
+			setMultipleChoicesDone((prev) => prev.filter((x) => x.id !== exercise.id));
+		}
+		// eslint-disable-next-line react-hooks/exhaustive-deps
+	}, [exerciseIndex, partIndex]);
+
+	const calculateExerciseIndex = () => {
+		if (partIndex === -1) return 0;
+		if (partIndex === 0)
+			return (
+				(exerciseIndex === -1 ? 0 : exerciseIndex + 1) + storeQuestionIndex + multipleChoicesDone.reduce((acc, curr) => acc + curr.amount, 0)
+			);
+
+		const exercisesPerPart = exam.parts.map((x) => x.exercises.length);
+		const exercisesDone = exercisesPerPart.filter((_, index) => index < partIndex).reduce((acc, curr) => curr + acc, 0);
+		return (
+			exercisesDone +
+			(exerciseIndex === -1 ? 0 : exerciseIndex + 1) +
+			storeQuestionIndex +
+			multipleChoicesDone.reduce((acc, curr) => acc + curr.amount, 0)
+		);
+	};
+
 	const renderText = () => (
 		<div className="flex flex-col gap-6 w-full bg-mti-gray-seasalt rounded-xl py-8 px-16 mt-4">
 			<div className="flex flex-col w-full gap-2">
@@ -216,19 +260,7 @@ export default function Reading({exam, showSolutions = false, onFinish}: Props)
 				{partIndex > -1 && <TextModal {...exam.parts[partIndex].text} isOpen={showTextModal} onClose={() => setShowTextModal(false)} />}
 				<ModuleTitle
 					minTimer={exam.minTimer}
-					exerciseIndex={
-						(exam.parts
-							.flatMap((x) => x.exercises)
-							.findIndex(
-								(x) =>
-									x.id ===
-									exam.parts[partIndex > -1 ? partIndex : 0].exercises[exerciseIndex === -1 ? exerciseIndex + 1 : exerciseIndex]
-										?.id,
-							) || 0) +
-						(exerciseIndex === -1 ? 0 : 1) +
-						questionIndex +
-						currentQuestionIndex
-					}
+					exerciseIndex={calculateExerciseIndex()}
 					module="reading"
 					totalExercises={countExercises(exam.parts.flatMap((x) => x.exercises))}
 					disableTimer={showSolutions}