Refactor Planviewer and fix tests

src/routes/delete-account/DeleteAccount.test.tsx

@@ -22,7 +22,10 @@ describe("DeleteAccount", () => {
   test("renders page title and account deletion steps", () => {
     setup();
     expect(
-      screen.getByRole("heading", { name: /delete your account/i }),
+      screen.getByRole("heading", {
+        level: 1,
+        name: /delete your account/i,
+      }),
     ).toBeInTheDocument();
     expect(screen.getByText(/open the webuddhist app/i)).toBeInTheDocument();
     expect(screen.getByText(/go to profile/i)).toBeInTheDocument();

src/routes/planviewer/Planviewer.tsx

@@ -52,13 +52,15 @@ const Planviewer = () => {
   );
 
   const handleSelectPlan = useCallback(
-    (planId: string) => {
+    (planId: string, date?: string) => {
       if (!selectedSeriesId) return;
-      setSearchParams({
+      const params: Record<string, string> = {
         series: selectedSeriesId,
         plan: planId,
         lang: apiLanguage,
-      });
+      };
+      if (date) params.date = date;
+      setSearchParams(params);
     },
     [apiLanguage, selectedSeriesId, setSearchParams],
   );

src/routes/planviewer/components/SeriesDetailView.tsx

@@ -16,7 +16,10 @@ import {
   resolveImageUrl,
   type PlanLanguageCode,
 } from "../utils/seriesUtils.ts";
-import { getPlanRowStatus } from "../utils/planStatusUtils.ts";
+import {
+  getPlanRowStatus,
+  resolvePlanInitialDate,
+} from "../utils/planStatusUtils.ts";
 import {
   getEarlyReturn,
   getLanguageClass,
@@ -28,7 +31,7 @@ type SeriesDetailViewProps = {
   apiLanguage: string;
   isAuthenticated: boolean;
   onBack: () => void;
-  onSelectPlan: (planId: string) => void;
+  onSelectPlan: (planId: string, date?: string) => void;
 };
 
 const SeriesDetailView = ({
@@ -187,7 +190,12 @@ const SeriesDetailView = ({
                   enrollment?.current_plan_id,
                 )}
                 contentFontClass={contentFontClass}
-                onSelect={onSelectPlan}
+                onSelect={(planId) =>
+                  onSelectPlan(
+                    planId,
+                    resolvePlanInitialDate(plan, today) ?? undefined,
+                  )
+                }
               />
             ))
           )}

src/routes/planviewer/utils/planStatusUtils.test.ts

@@ -1,5 +1,8 @@
 import { describe, expect, test } from "vitest";
-import { resolveTodaysPlanId } from "./planStatusUtils.ts";
+import {
+  resolvePlanInitialDate,
+  resolveTodaysPlanId,
+} from "./planStatusUtils.ts";
 import type { SeriesPlanDTO } from "../types.ts";
 
 const plans: SeriesPlanDTO[] = [
@@ -40,3 +43,29 @@ describe("resolveTodaysPlanId", () => {
     expect(resolveTodaysPlanId([], "EN")).toBeNull();
   });
 });
+
+describe("resolvePlanInitialDate", () => {
+  // plan-1: 2026-05-14 .. 2026-05-19 (6 days)
+  // plan-2: 2026-05-20 .. 2026-06-19 (31 days)
+  test("returns today when today is within the plan window", () => {
+    const today = new Date("2026-06-10T12:00:00");
+    expect(resolvePlanInitialDate(plans[1], today)).toBe("2026-06-10");
+  });
+
+  test("returns the plan's first day when today is after the window", () => {
+    const today = new Date("2026-06-25T12:00:00");
+    expect(resolvePlanInitialDate(plans[0], today)).toBe("2026-05-14");
+  });
+
+  test("returns the plan's first day when today is before the window", () => {
+    const today = new Date("2026-05-01T12:00:00");
+    expect(resolvePlanInitialDate(plans[1], today)).toBe("2026-05-20");
+  });
+
+  test("returns null when the plan has no start_date", () => {
+    const today = new Date("2026-06-10T12:00:00");
+    expect(
+      resolvePlanInitialDate({ ...plans[0], start_date: null }, today),
+    ).toBeNull();
+  });
+});

src/routes/planviewer/utils/planStatusUtils.ts

@@ -17,6 +17,22 @@ function addDays(date: Date, days: number): Date {
   return next;
 }
 
+function toIsoDate(date: Date): string {
+  const pad = (n: number) => String(n).padStart(2, "0");
+  return `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())}`;
+}
+
+export function resolvePlanInitialDate(
+  plan: SeriesPlanDTO,
+  today: Date = new Date(),
+): string | null {
+  if (!plan.start_date) return null;
+  const start = toDateOnly(plan.start_date);
+  const end = addDays(start, Math.max(plan.total_days, 1) - 1);
+  if (today >= start && today <= end) return toIsoDate(today);
+  return toIsoDate(start);
+}
+
 export function formatPlanDateRange(
   startDate: string | null | undefined,
   totalDays: number,