feat: enable explanation overrides

Author: wackerow

src/data/quizzes/questionBank.ts

@@ -1,4 +1,8 @@
-import type { QuestionBank, QuestionBankConfig } from "@/lib/types"
+import type {
+  ChoiceLetter,
+  QuestionBank,
+  QuestionBankConfig,
+} from "@/lib/types"
 
 /**
  * This file is used to generate the question bank for the quizzes.
@@ -30,6 +34,25 @@ import type { QuestionBank, QuestionBankConfig } from "@/lib/types"
  * - "what-is-ethereum-1-c-explanation"
  * - "what-is-ethereum-1-d-label"
  * - "what-is-ethereum-1-d-explanation"
+ *
+ * To re-use answer explanations from other choices within the same question,
+ * append an optional explanationOverrides array to the question object.
+ * This take the format of an array of 1-indexed answer choices to re-use, with
+ * the position in the array representing which question to override. First
+ * position is "a".
+ *
+ * Example - Re-use the first answer explanation for all choices:
+ * "what-is-ethereum": [
+ * { totalAnswers: 4, correctAnswer: 2, explanationOverrides: [1, 1, 1, 1] }
+ * ]
+ *
+ * With that alteration, requires the following strings in learn-quizzes.json:
+ * - "what-is-ethereum-1-prompt"
+ * - "what-is-ethereum-1-a-label"
+ * - "what-is-ethereum-1-a-explanation"
+ * - "what-is-ethereum-1-b-label"
+ * - "what-is-ethereum-1-c-label"
+ * - "what-is-ethereum-1-d-label"
  */
 const questionBankConfig: QuestionBankConfig = {
   "what-is-ethereum": [
@@ -137,19 +160,26 @@ const charFromIdx = (idx: number) => String.fromCharCode(97 + idx)
 const questionBank = Object.entries(questionBankConfig).reduce(
   (acc, [topicKey, value]) => {
     for (const [idx, question] of value.entries()) {
-      const { totalAnswers, correctAnswer } = question
+      const { totalAnswers, correctAnswer, explanationOverrides } = question
       const questionKey = `${topicKey}-${idx + 1}`
       const questionObject = {
         prompt: `${questionKey}-prompt`,
         answers: Array(totalAnswers)
           .fill(0)
           .map((_, i) => {
-            const choice = charFromIdx(i) as "a" | "b" | "c" | "d"
+            const choice = charFromIdx(i) as ChoiceLetter
+            const exIdx =
+              explanationOverrides && explanationOverrides[i]
+                ? explanationOverrides[i] - 1
+                : i
+            const exLetter = charFromIdx(exIdx) as ChoiceLetter
+
             const id = `${questionKey}-${choice}`
+            const exId = `${questionKey}-${exLetter}`
             return {
               id,
               label: `${id}-label`,
-              explanation: `${id}-explanation`,
+              explanation: `${exId}-explanation`,
             }
           }),
         correctAnswerId: `${questionKey}-${charFromIdx(correctAnswer - 1)}`,

src/lib/types.ts

@@ -161,13 +161,19 @@ export type LoadingState<T> =
   | { loading: false; data: T }
   | { loading: false; error: unknown }
 
-/**
- * Quiz data types
- */
-export type QuestionTemplate = {
-  totalAnswers: 2 | 3 | 4
-  correctAnswer: 1 | 2 | 3 | 4
+// Quiz data types
+
+export type ChoiceLetter = "a" | "b" | "c" | "d"
+
+type ChoiceNumber = 1 | 2 | 3 | 4
+type TotalAnswers = 2 | 3 | 4
+
+type QuestionTemplate = {
+  totalAnswers: TotalAnswers
+  correctAnswer: ChoiceNumber
+  explanationOverrides?: (ChoiceNumber | null)[] // Tuple<ChoiceNumber, QuestionTemplate["totalAnswers"]>
 }
+
 export type QuestionBankConfig = Record<string, QuestionTemplate[]>
 
 export type Answer = {