feat(exam): add SAT style testing component

src/stores/useSatExam.ts

@@ -0,0 +1,127 @@
+import { create } from "zustand";
+import { persist } from "zustand/middleware";
+import { type ExamPhase } from "../types/sheet";
+import type { SessionModuleQuestions } from "../types/session";
+
+// interface SatExamState {
+//   modules: Module[];
+//   phase: ExamPhase;
+//   moduleIndex: number;
+//   questionIndex: number;
+//   endTime: number | null;
+
+//   startExam: () => void;
+//   setModuleQuestionss: (modules: Module[]) => void;
+
+//   nextQuestion: () => void;
+//   prevQuestion: () => void;
+//   nextModule: () => void;
+//   nextPhase: () => void;
+//   skipBreak: () => void;
+//   getRemainingTime: () => number;
+//   finishExam: () => void;
+//   resetExam: () => void;
+//   replaceModules: (modules: Module[]) => void;
+// }
+
+interface SatExamState {
+  currentModuleQuestions: SessionModuleQuestions | null;
+  phase: ExamPhase;
+  questionIndex: number;
+  endTime: number | null;
+
+  setModuleQuestions: (module: SessionModuleQuestions) => void;
+  startExam: () => void;
+  nextQuestion: () => void;
+  prevQuestion: () => void;
+
+  startBreak: () => void;
+  skipBreak: () => void;
+  finishExam: () => void;
+  resetExam: () => void;
+  getRemainingTime: () => number;
+}
+
+const BREAK_DURATION = 30; // seconds
+
+export const useSatExam = create<SatExamState>()(
+  persist(
+    (set, get) => ({
+      currentModuleQuestions: null,
+      phase: "IDLE",
+      questionIndex: 0,
+      endTime: null,
+
+      setModuleQuestions: (module: SessionModuleQuestions) => {
+        const endTime = Date.now() + module.time_limit_minutes * 1000;
+
+        set({
+          currentModuleQuestions: module,
+          questionIndex: 0,
+          endTime,
+        });
+      },
+
+      startExam: () => {
+        set({ phase: "MODULE", questionIndex: 0 });
+      },
+
+      nextQuestion: () => {
+        const { currentModuleQuestions, questionIndex } = get();
+        const questions = currentModuleQuestions?.questions ?? [];
+
+        if (questionIndex < questions.length - 1) {
+          set({ questionIndex: questionIndex + 1 });
+        }
+      },
+
+      prevQuestion: () => {
+        const { questionIndex } = get();
+        if (questionIndex > 0) {
+          set({ questionIndex: questionIndex - 1 });
+        }
+      },
+
+      startBreak: () => {
+        const endTime = Date.now() + BREAK_DURATION * 1000;
+
+        set((state) => ({
+          phase: "BREAK",
+          endTime,
+          questionIndex: 0, // optional: reset question index for next module UX
+        }));
+      },
+
+      skipBreak: () => {
+        const module = get().currentModuleQuestions;
+
+        if (!module) return;
+
+        const endTime = Date.now() + module.time_limit_minutes * 1000;
+
+        set({
+          phase: "MODULE",
+          endTime,
+          questionIndex: 0,
+        });
+      },
+
+      finishExam: () => set({ phase: "FINISHED", endTime: null }),
+
+      getRemainingTime: () => {
+        const { endTime } = get();
+        if (!endTime) return 0;
+        return Math.max(0, Math.floor((endTime - Date.now()) / 1000));
+      },
+
+      resetExam: () =>
+        set({
+          currentModuleQuestions: null,
+          phase: "IDLE",
+          questionIndex: 0,
+          endTime: null,
+        }),
+    }),
+    { name: "sat-exam-storage" },
+  ),
+);