diff --git a/docs/user-flows.md b/docs/user-flows.md
index 36561d8..a737185 100644
--- a/docs/user-flows.md
+++ b/docs/user-flows.md
@@ -175,6 +175,11 @@ either an all-days overview or one specific day. Tap → open the route.
   (`replaceState`), never pushing a new entry. So repeated toggling can't pile up duplicate
   entries (the old bug where Back needed ~10 presses and the form appeared wiped).
 - **Deep links** — every search is a shareable URL; legacy `?rdate=` / `?rt=` links still work.
+  A station may be named in any case or accent (`from=paris`, `to=LILLE`) and resolves to
+  the station that has trains; a name matching no station shows "Unknown station" instead
+  of an empty result. A malformed or out-of-window departure date falls back to today; a
+  malformed or out-of-window return or finish-by date, and a malformed time filter, are
+  dropped. The address bar is then corrected in place (`replaceState`) to match the screen.
 - **PWA** — installable; a "new version — reload" postcard on updates.
 
 ## Known open items (see docs/trip-redesign.md for the audit plan)
diff --git a/src/app.ts b/src/app.ts
index 7d96bf7..a414d9b 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -689,14 +689,17 @@ export function initApp(root: HTMLElement, dataset: Dataset, registry: StationRe
 }
 
 /**
- * Parse the query from the URL and snap its date back into the bookable window. The
- * date <input> is clamped to [today, today+29], so the search form can never produce
- * an out-of-range date — but a stale or shared link can. An out-of-window date would
- * otherwise collapse the ±flex browse window (only the chosen, unbookable day is in
- * range) and skew the exact-trip return calendar, so fall back to today.
+ * Parse the query from the URL, resolve its station names, snap its dates back into the
+ * bookable window, and correct the address bar to match. The date <input> is clamped
+ * to [today, today+29], so the search form can never produce an out-of-range date — but
+ * a stale or shared link can. An out-of-window date would otherwise collapse the ±flex
+ * browse window (only the chosen, unbookable day is in range) and skew the exact-trip
+ * return calendar, so fall back to today.
  */
 function queryFromUrl(): SearchQuery {
-  const q = store.queryFromParams(new URLSearchParams(location.search), today);
+  const params = new URLSearchParams(location.search);
+  const linked = params.toString();
+  const q = store.queryFromParams(params, today);
   const lastBookable = addDays(today, BOOKING_WINDOW_DAYS - 1);
   const inWindow = (d: string): boolean => d >= today && d <= lastBookable;
   if (!inWindow(q.date)) q.date = today;
@@ -713,11 +716,34 @@ function queryFromUrl(): SearchQuery {
   if (q.returnDate && q.mode === "od" && q.returnDate >= q.date && q.stay !== "flexible") {
     q.stay = stayFromNights(dayIndex(q.returnDate) - dayIndex(q.date));
   }
+  // A linked station name ("paris", "LILLE") becomes the id the data uses; a name
+  // matching no station is kept, and renderSearch reports it.
+  const station = (name: string): string => deps.registry.resolve(name) ?? name;
+  if (q.origin) q.origin = station(q.origin);
+  if (q.destination) q.destination = station(q.destination);
+  if (q.via) q.via = station(q.via);
+  q.cities = q.cities?.map(station);
   // Multi-city legs are clamped too: a leg outside the bookable window can never
   // have a free MAX seat, so pull it back to today rather than showing an empty leg.
-  if (q.legs) q.legs = q.legs.map((l) => (inWindow(l.date) ? l : { ...l, date: today }));
+  q.legs = q.legs?.map((l) => ({
+    from: station(l.from),
+    to: station(l.to),
+    date: inWindow(l.date) ? l.date : today,
+  }));
   // The tour "finish by" date only constrains the plan when it's inside the window.
   if (q.tourEndDate && !inWindow(q.tourEndDate)) q.tourEndDate = undefined;
+  // Write every value dropped, clamped or resolved above back into the address bar, in
+  // place, so a reload or a shared link carries what is on screen.
+  const parsed = store.queryToParams(q);
+  for (const key of ["from", "to", "via", "cities", "legs", "date", "rdate", "by", "after", "before", "arrbefore"]) {
+    if (!params.has(key)) continue;
+    const value = parsed.get(key);
+    if (value) params.set(key, value);
+    else params.delete(key);
+  }
+  if (params.toString() !== linked) {
+    history.replaceState(history.state, "", `${location.pathname}?${params.toString()}`);
+  }
   return q;
 }
 
@@ -1815,6 +1841,23 @@ function renderSearch(): void {
     );
   }
 
+  // Only a link can name a station the registry lacks (the form resolves to known ids):
+  // say so, rather than "No MAX seat" for a place that does not exist.
+  const unknown = [
+    query.origin,
+    query.destination,
+    query.via,
+    ...(query.cities ?? []),
+    ...(query.legs ?? []).flatMap((l) => [l.from, l.to]),
+  ].find((s) => s && !deps.registry.get(s));
+  if (unknown) {
+    refs.title.textContent = "";
+    refs.results.append(render.emptyEl(t("err_station", { station: unknown })));
+    showBaseMap();
+    updateSearchBar();
+    return;
+  }
+
   // MAX SENIOR free tickets are weekday-only — flag a weekend outbound, and (round trip)
   // a weekend RETURN on a later day, since either leg must be booked free.
   if (query.card === "senior") {
diff --git a/src/data/stations.ts b/src/data/stations.ts
index b2ac459..e0a0378 100644
--- a/src/data/stations.ts
+++ b/src/data/stations.ts
@@ -154,6 +154,19 @@ export class StationRegistry {
     return this.byId.get(id);
   }
 
+  /** The id a linked name means: a bookable id as is, else the id, label or alias equal to
+   *  it ignoring case, accents and "St"/hyphen spelling, preferring one with trains. */
+  resolve(name: string): string | undefined {
+    if (this.present.has(name)) return name;
+    const n = matchNorm(name);
+    let best: Station | undefined;
+    for (const { station } of this.index) {
+      const names = [station.id, station.label, ...(station.aliases ?? [])];
+      if (names.some((s) => matchNorm(s) === n) && (!best || this.better(station, best))) best = station;
+    }
+    return best?.id;
+  }
+
   /** Every registered station (may contain label duplicates). */
   all(): Station[] {
     return [...this.byId.values()];
diff --git a/src/i18n/ar.ts b/src/i18n/ar.ts
index f13aa60..f4d984a 100644
--- a/src/i18n/ar.ts
+++ b/src/i18n/ar.ts
@@ -16,6 +16,8 @@ export const ar: Dict = {
   datepick_window: "المنقّط = الأيام ضمن هامش ±",
   err_load: "تعذّر تحميل البيانات.",
   act_retry: "إعادة المحاولة",
+  err_app: "تعذّر فتح هذه الصفحة.",
+  err_station: "محطة غير معروفة: «{station}». اختر محطة من القائمة.",
   tagline: "مقاعد MAX JEUNE / SENIOR المتاحة للحجز.",
   mode_best: "أفكار",
   best_title_all: "كل الوجهات من {station}",
diff --git a/src/i18n/de.ts b/src/i18n/de.ts
index 6077c82..ed5ef37 100644
--- a/src/i18n/de.ts
+++ b/src/i18n/de.ts
@@ -16,6 +16,8 @@ export const de: Dict = {
   datepick_window: "gepunktet = Tage innerhalb der ±-Spanne",
   err_load: "Daten konnten nicht geladen werden.",
   act_retry: "Erneut versuchen",
+  err_app: "Diese Seite konnte nicht geöffnet werden.",
+  err_station: "Unbekannter Bahnhof: „{station}“. Wähle einen aus der Liste.",
   tagline: "Reservierbare MAX JEUNE / SENIOR Plätze.",
   mode_best: "Ideen",
   best_title_all: "Alle Ziele ab {station}",
diff --git a/src/i18n/en.ts b/src/i18n/en.ts
index 3b92000..0f52150 100644
--- a/src/i18n/en.ts
+++ b/src/i18n/en.ts
@@ -16,6 +16,8 @@ export const en: Dict = {
   datepick_window: "dotted = days within the ± margin",
   err_load: "Couldn't load the data.",
   act_retry: "Retry",
+  err_app: "This page couldn't be opened.",
+  err_station: "Unknown station: “{station}”. Pick one from the list.",
   tagline: "MAX JEUNE / SENIOR seats open for reservation.",
   mode_best: "Ideas",
   best_title_all: "All destinations from {station}",
diff --git a/src/i18n/es.ts b/src/i18n/es.ts
index 938e7ed..cf36eb3 100644
--- a/src/i18n/es.ts
+++ b/src/i18n/es.ts
@@ -16,6 +16,8 @@ export const es: Dict = {
   datepick_window: "punteado = días dentro del margen ±",
   err_load: "No se pudieron cargar los datos.",
   act_retry: "Reintentar",
+  err_app: "No se pudo abrir esta página.",
+  err_station: "Estación desconocida: «{station}». Elige una de la lista.",
   tagline: "Plazas MAX JEUNE / SENIOR abiertas a reserva.",
   mode_best: "Ideas",
   best_title_all: "Todos los destinos desde {station}",
diff --git a/src/i18n/fr.ts b/src/i18n/fr.ts
index 4c788a3..5fb6061 100644
--- a/src/i18n/fr.ts
+++ b/src/i18n/fr.ts
@@ -14,6 +14,8 @@ export const fr = {
   datepick_window: "pointillés = jours compris dans la marge ±",
   err_load: "Impossible de charger les données.",
   act_retry: "Réessayer",
+  err_app: "Cette page n'a pas pu s'ouvrir.",
+  err_station: "Gare inconnue : «\u00a0{station}\u00a0». Choisissez-en une dans la liste.",
   tagline: "Places MAX JEUNE / SENIOR ouvertes à la réservation.",
   mode_best: "Idées",
   best_title_all: "Toutes les destinations depuis {station}",
diff --git a/src/i18n/it.ts b/src/i18n/it.ts
index c67cf2c..2c45630 100644
--- a/src/i18n/it.ts
+++ b/src/i18n/it.ts
@@ -16,6 +16,8 @@ export const it: Dict = {
   datepick_window: "punteggiato = giorni entro il margine ±",
   err_load: "Impossibile caricare i dati.",
   act_retry: "Riprova",
+  err_app: "Impossibile aprire questa pagina.",
+  err_station: "Stazione sconosciuta: «{station}». Scegline una dall'elenco.",
   tagline: "Posti MAX JEUNE / SENIOR aperti alla prenotazione.",
   mode_best: "Idee",
   best_title_all: "Tutte le destinazioni da {station}",
diff --git a/src/i18n/ja.ts b/src/i18n/ja.ts
index 377cafd..04a7754 100644
--- a/src/i18n/ja.ts
+++ b/src/i18n/ja.ts
@@ -16,6 +16,8 @@ export const ja: Dict = {
   datepick_window: "点線 = ±範囲内の日",
   err_load: "データを読み込めませんでした。",
   act_retry: "再試行",
+  err_app: "このページを開けませんでした。",
+  err_station: "不明な駅：「{station}」。リストから選んでください。",
   tagline: "予約できる MAX JEUNE / SENIOR の座席。",
   mode_best: "おすすめ",
   best_title_all: "{station} から行ける全ての行き先",
diff --git a/src/i18n/ko.ts b/src/i18n/ko.ts
index 39fc01b..1519624 100644
--- a/src/i18n/ko.ts
+++ b/src/i18n/ko.ts
@@ -16,6 +16,8 @@ export const ko: Dict = {
   datepick_window: "점선 = ± 범위 내의 날짜",
   err_load: "데이터를 불러올 수 없습니다.",
   act_retry: "다시 시도",
+  err_app: "이 페이지를 열 수 없습니다.",
+  err_station: "알 수 없는 역: “{station}”. 목록에서 선택하세요.",
   tagline: "예약 가능한 MAX JEUNE / SENIOR 좌석.",
   mode_best: "추천",
   best_title_all: "{station}에서 갈 수 있는 모든 목적지",
diff --git a/src/i18n/nl.ts b/src/i18n/nl.ts
index e11ec2a..12a5193 100644
--- a/src/i18n/nl.ts
+++ b/src/i18n/nl.ts
@@ -16,6 +16,8 @@ export const nl: Dict = {
   datepick_window: "stippellijn = dagen binnen de ±-marge",
   err_load: "Kan de gegevens niet laden.",
   act_retry: "Opnieuw proberen",
+  err_app: "Deze pagina kan niet worden geopend.",
+  err_station: "Onbekend station: “{station}”. Kies er een uit de lijst.",
   tagline: "MAX JEUNE / SENIOR-plaatsen die te reserveren zijn.",
   mode_best: "Ideeën",
   best_title_all: "Alle bestemmingen vanaf {station}",
diff --git a/src/i18n/pt.ts b/src/i18n/pt.ts
index fd411b4..7475064 100644
--- a/src/i18n/pt.ts
+++ b/src/i18n/pt.ts
@@ -16,6 +16,8 @@ export const pt: Dict = {
   datepick_window: "pontilhado = dias dentro da margem ±",
   err_load: "Não foi possível carregar os dados.",
   act_retry: "Tentar novamente",
+  err_app: "Não foi possível abrir esta página.",
+  err_station: "Estação desconhecida: «{station}». Escolha uma da lista.",
   tagline: "Lugares MAX JEUNE / SENIOR abertos para reserva.",
   mode_best: "Ideias",
   best_title_all: "Todos os destinos a partir de {station}",
diff --git a/src/i18n/zh.ts b/src/i18n/zh.ts
index 8b34164..5c633ac 100644
--- a/src/i18n/zh.ts
+++ b/src/i18n/zh.ts
@@ -16,6 +16,8 @@ export const zh: Dict = {
   datepick_window: "虚线 = ± 范围内的日期",
   err_load: "无法加载数据。",
   act_retry: "重试",
+  err_app: "无法打开此页面。",
+  err_station: "未知车站：“{station}”。请从列表中选择。",
   tagline: "可预订的 MAX JEUNE / SENIOR 座位。",
   mode_best: "推荐",
   best_title_all: "从{station}出发的所有目的地",
diff --git a/src/main.ts b/src/main.ts
index a1d44ab..9d4aec9 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -27,20 +27,20 @@ function loadingStateEl(): HTMLElement {
   ]);
 }
 
-/** Clean error card with a retry action if the dataset fails to load. */
-function errorStateEl(): HTMLElement {
+/** Clean error card with a retry action: the data failed to load, or the page failed to open. */
+function errorStateEl(message: string, retry: () => void): HTMLElement {
   return el("div", { class: "error-state", attrs: { role: "alert" } }, [
     el("span", {
       class: "error-icon",
       attrs: { "aria-hidden": "true" },
       html: `<svg viewBox="0 0 24 24" width="30" height="30" fill="none" stroke="currentColor" stroke-width="1.7" stroke-linecap="round" stroke-linejoin="round"><path d="M12 9v4M12 17h.01"/><path d="M10.3 3.9 1.8 18a2 2 0 0 0 1.7 3h17a2 2 0 0 0 1.7-3L13.7 3.9a2 2 0 0 0-3.4 0z"/></svg>`,
     }),
-    el("p", { class: "error-title", text: t("err_load") }),
+    el("p", { class: "error-title", text: message }),
     el("button", {
       class: "btn btn-primary",
       type: "button",
       text: t("act_retry"),
-      on: { click: () => location.reload() },
+      on: { click: retry },
     }),
   ]);
 }
@@ -61,12 +61,21 @@ if (root) {
     root.replaceChildren(loadingStateEl());
   }
   const registry = new StationRegistry(stationData as Station[]);
-  loadDataset()
-    .then((dataset) => initApp(root, dataset, registry))
-    .catch((err: unknown) => {
+  loadDataset().then(
+    (dataset) => {
+      try {
+        initApp(root, dataset, registry);
+      } catch (err) {
+        // The data loaded but this link or saved state broke the page: retry without the link.
+        console.error(err);
+        root.replaceChildren(errorStateEl(t("err_app"), () => location.assign(location.pathname)));
+      }
+    },
+    (err: unknown) => {
       console.error(err);
-      root.replaceChildren(errorStateEl());
-    });
+      root.replaceChildren(errorStateEl(t("err_load"), () => location.reload()));
+    },
+  );
 }
 
 // When a new build is deployed, greet the user with a dismissible "reload to update"
diff --git a/src/state/store.ts b/src/state/store.ts
index 16aa07d..159d906 100644
--- a/src/state/store.ts
+++ b/src/state/store.ts
@@ -1,7 +1,7 @@
 import type { SearchQuery, SearchMode, CardType, Journey, SortKey, TripLeg, StayChoice } from "../types";
 import type { Tour } from "../core/tour";
 import { stayFromNights } from "../core/roundtrip";
-import { dayIndex } from "../util/time";
+import { dayIndex, parseTimeToMinutes } from "../util/time";
 import { isLang, detectLang, type Lang } from "../i18n";
 
 /** URL token for a stay choice (compact + stable): stay=day|<N>|flex, where <N> is the
@@ -124,8 +124,20 @@ function sameRoute(a: RoutePair, b: RoutePair): boolean {
   return a.origin === b.origin && a.destination === b.destination;
 }
 
+// Stored lists are checked per element: one malformed entry is dropped instead of
+// crashing every render that reads the list.
+type Stored = Record<string, unknown>;
+
+function isStored(v: unknown): v is Stored {
+  return typeof v === "object" && v !== null;
+}
+
+function isRoutePair(v: unknown): v is RoutePair & Stored {
+  return isStored(v) && typeof v.origin === "string" && typeof v.destination === "string";
+}
+
 export function loadFavorites(): RoutePair[] {
-  return readLS<RoutePair[]>(KEY.favorites, [], Array.isArray);
+  return readLS<unknown[]>(KEY.favorites, [], Array.isArray).filter(isRoutePair);
 }
 
 export function isFavorite(r: RoutePair): boolean {
@@ -142,7 +154,7 @@ export function toggleFavorite(r: RoutePair): RoutePair[] {
 }
 
 export function loadWatched(): RoutePair[] {
-  return readLS<RoutePair[]>(KEY.watched, [], Array.isArray);
+  return readLS<unknown[]>(KEY.watched, [], Array.isArray).filter(isRoutePair);
 }
 
 export function isWatched(r: RoutePair): boolean {
@@ -190,8 +202,30 @@ export function tourId(tour: Tour): string {
   return `tour:${tour.legs.map(journeyKey).join("|")}`;
 }
 
+/** What a saved-trip row and its dialog read: dated endpoints, dated legs, the hub lists. */
+function isJourney(v: unknown): v is Journey {
+  const dated = (x: unknown): x is Stored => isRoutePair(x) && isValidIsoDate(x.date);
+  return (
+    dated(v) &&
+    Array.isArray(v.legs) &&
+    v.legs.length > 0 &&
+    v.legs.every(dated) &&
+    Array.isArray(v.hubs) &&
+    Array.isArray(v.layovers)
+  );
+}
+
+function isSavedTrip(v: unknown): v is SavedTrip {
+  return (
+    isStored(v) &&
+    isJourney(v.outbound) &&
+    (v.inbound == null || isJourney(v.inbound)) &&
+    (v.tour == null || (isStored(v.tour) && Array.isArray(v.tour.legs) && v.tour.legs.every(isJourney)))
+  );
+}
+
 export function loadTrips(): SavedTrip[] {
-  return readLS<SavedTrip[]>(KEY.trips, [], Array.isArray);
+  return readLS<unknown[]>(KEY.trips, [], Array.isArray).filter(isSavedTrip);
 }
 
 export function isTripSaved(id: string): boolean {
@@ -293,6 +327,16 @@ export function queryFromParams(p: URLSearchParams, fallbackDate: string): Searc
   const stayh = Number(p.get("stayh"));
   const clampDay = (n: number, fallback: number): number =>
     Number.isFinite(n) && n >= 1 ? Math.min(14, Math.floor(n)) : fallback;
+  // A malformed date or time is dropped: kept, a date crashes the render and a time
+  // filters out every train while the form shows no filter.
+  const isoDate = (key: string): string | undefined => {
+    const v = p.get(key);
+    return v && isValidIsoDate(v) ? v : undefined;
+  };
+  const time = (key: string): string | undefined => {
+    const v = p.get(key);
+    return v && /^\d{2}:\d{2}$/.test(v) && Number.isFinite(parseTimeToMinutes(v)) ? v : undefined;
+  };
   return {
     mode,
     origin: p.get("from") ?? undefined,
@@ -306,13 +350,13 @@ export function queryFromParams(p: URLSearchParams, fallbackDate: string): Searc
     // Clamp to the stepper's 0..7 range (like setStepper) — an out-of-range link
     // should mean "the widest window", not silently fall back to no flexibility.
     flexDays: Number.isFinite(Number(p.get("flex"))) && Math.floor(Number(p.get("flex"))) >= 1 ? Math.min(7, Math.floor(Number(p.get("flex")))) : undefined,
-    returnDate: p.get("rdate") ?? undefined,
+    returnDate: isoDate("rdate"),
     legs: parseLegs(p.get("legs")),
-    date: p.get("date") ?? fallbackDate,
+    date: isoDate("date") ?? fallbackDate,
     card: p.get("card") === "senior" ? "senior" : "jeune",
-    departAfter: p.get("after") ?? undefined,
-    departBefore: p.get("before") ?? undefined,
-    arriveBefore: p.get("arrbefore") ?? undefined,
+    departAfter: time("after"),
+    departBefore: time("before"),
+    arriveBefore: time("arrbefore"),
     maxDurationMin: Number.isFinite(maxdur) && maxdur > 0 ? maxdur : undefined,
     trainType: p.get("type") ?? undefined,
     maxConnections: Number.isFinite(conn) && conn >= 0 && conn <= 6 ? conn : 1,
@@ -340,7 +384,7 @@ export function queryFromParams(p: URLSearchParams, fallbackDate: string): Searc
     flexNights: p.get("fn") === "1" || undefined,
     stayMinHours: Number.isFinite(stayh) && stayh >= 1 ? Math.min(12, Math.floor(stayh)) : undefined,
     lateReturn: p.get("late") === "1" || undefined,
-    tourEndDate: p.get("by") ?? undefined,
+    tourEndDate: isoDate("by"),
     sort: parseSort(p.get("sort")),
   };
 }
@@ -381,11 +425,11 @@ function parseStay(p: URLSearchParams): StayChoice | undefined {
 // require a real ISO date so both are impossible from a URL.
 const MAX_LEGS = 12;
 
-/** Whether a string is a well-formed, real ISO date (YYYY-MM-DD). */
-function isValidIsoDate(d: string): boolean {
-  if (!/^\d{4}-\d{2}-\d{2}$/.test(d)) return false;
-  const t = new Date(`${d}T00:00:00`).getTime();
-  return !Number.isNaN(t);
+/** Whether a value is a real calendar date written YYYY-MM-DD (not 2026-10-1 or 2026-02-30). */
+function isValidIsoDate(d: unknown): d is string {
+  if (typeof d !== "string") return false;
+  const t = Date.parse(`${d}T00:00:00Z`);
+  return Number.isFinite(t) && new Date(t).toISOString().slice(0, 10) === d;
 }
 
 /** Parse the "legs" param (from>to@date, ~-joined) into multi-city legs. */
diff --git a/src/styles.css b/src/styles.css
index 926bb3f..0e3c4ec 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -1507,6 +1507,7 @@ a {
   padding: 1.6rem;
   text-align: center;
   color: var(--muted);
+  overflow-wrap: anywhere; /* a long unbroken name from a link wraps instead of clipping */
 }
 .empty-hint {
   margin: 0.55rem 0 0;
diff --git a/tests/crash-guards.test.ts b/tests/crash-guards.test.ts
new file mode 100644
index 0000000..0c89181
--- /dev/null
+++ b/tests/crash-guards.test.ts
@@ -0,0 +1,190 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+
+// Leaflet needs a real browser canvas; stub the map module so the rest of the
+// UI can be exercised under jsdom.
+vi.mock("../src/ui/map", () => ({
+  RouteMap: class {
+    onSelect: ((id: string) => void) | null = null;
+    show(): void {}
+    route(): void {}
+    radius(): void {}
+    base(): void {}
+    highlight(): void {}
+    invalidate(): void {}
+    focus(): void {}
+    setInfo(): void {}
+  },
+}));
+
+import type { RawRecord, Station, DataMeta } from "../src/types";
+import { normalizeRecords } from "../src/data/dataset";
+import { StationRegistry } from "../src/data/stations";
+import { initApp } from "../src/app";
+import { queryFromParams, loadFavorites, loadWatched, loadTrips } from "../src/state/store";
+import { en } from "../src/i18n/en";
+import sample from "../data/tgvmax.sample.json";
+import stations from "../data/stations.json";
+
+const meta: DataMeta = { updatedAt: "", source: "sample", recordCount: 0, isSample: true };
+const P = encodeURIComponent("PARIS (intramuros)");
+const L = encodeURIComponent("LYON (intramuros)");
+
+function setup(search: string, rows = sample as RawRecord[]): HTMLElement {
+  document.body.innerHTML = '<div id="app"></div>';
+  const root = document.getElementById("app") as HTMLElement;
+  history.replaceState(null, "", `/${search}`);
+  initApp(root, { trains: normalizeRecords(rows), meta }, new StationRegistry(stations as Station[]));
+  return root;
+}
+
+const journey = {
+  date: "2026-06-25",
+  origin: "PARIS (intramuros)",
+  destination: "LYON (intramuros)",
+  legs: [{ date: "2026-06-25", origin: "PARIS (intramuros)", destination: "LYON (intramuros)", trainNo: "6601" }],
+  departMin: 480,
+  arriveMin: 600,
+  totalDurationMin: 120,
+  layovers: [],
+  hubs: [],
+};
+
+beforeEach(() => {
+  localStorage.clear();
+  // Pin "today" to the sample-data epoch so its dates sit inside the bookable window.
+  vi.useFakeTimers({ toFake: ["Date"] });
+  vi.setSystemTime(new Date("2026-06-25T12:00:00Z"));
+  globalThis.requestAnimationFrame = ((cb: FrameRequestCallback) => {
+    cb(0);
+    return 0;
+  }) as typeof requestAnimationFrame;
+  Element.prototype.scrollIntoView = function scrollIntoView(): void {};
+});
+
+afterEach(() => {
+  vi.useRealTimers();
+});
+
+describe("a malformed date or time in a link (H1)", () => {
+  it("drops dates that are not real YYYY-MM-DD calendar days, and unparseable times", () => {
+    for (const bad of ["2026-10-1", "2026-10-00", "2026-02-30", "garbage"]) {
+      const q = queryFromParams(new URLSearchParams({ date: bad, rdate: bad, by: bad }), "2026-06-25");
+      expect(q.date).toBe("2026-06-25");
+      expect(q.returnDate).toBeUndefined();
+      expect(q.tourEndDate).toBeUndefined();
+    }
+    const q = queryFromParams(new URLSearchParams({ after: "garbage", before: "25:99", arrbefore: "8:00" }), "2026-06-25");
+    expect([q.departAfter, q.departBefore, q.arriveBefore]).toEqual([undefined, undefined, undefined]);
+    expect(queryFromParams(new URLSearchParams({ after: "08:30" }), "2026-06-25").departAfter).toBe("08:30");
+  });
+
+  it("opens the trip on today instead of throwing, and puts today in the address bar", () => {
+    // Both sort inside the bookable window as strings, so only the date check catches them.
+    for (const bad of ["2026-06-3", "2026-07-00"]) {
+      const root = setup(`?mode=od&from=${P}&to=${L}&date=${bad}&rdate=${bad}&lang=en`);
+      expect(root.querySelector(".mode-tab.active")).not.toBeNull();
+      const url = new URLSearchParams(location.search);
+      expect(url.get("date")).toBe("2026-06-25");
+      expect(url.has("rdate")).toBe(false);
+      expect(url.get("lang")).toBe("en");
+    }
+  });
+
+  it("rewrites an out-of-window date in place, without a new history entry", () => {
+    const before = history.length;
+    setup(`?mode=od&from=${P}&to=${L}&date=2020-01-01`);
+    expect(new URLSearchParams(location.search).get("date")).toBe("2026-06-25");
+    expect(history.length).toBe(before);
+  });
+
+  it("ignores an unparseable time filter rather than hiding every train", () => {
+    const root = setup(`?mode=od&from=${P}&to=${L}&date=2026-06-25&after=garbage&lang=en`);
+    expect(root.textContent).not.toContain(en.res_none);
+    expect(new URLSearchParams(location.search).has("after")).toBe(false);
+  });
+});
+
+describe("a malformed entry in a stored list (H2)", () => {
+  it("drops the bad entries and keeps the good ones", () => {
+    const fav = { origin: "PARIS (intramuros)", destination: "LYON (intramuros)" };
+    localStorage.setItem("mj.favorites", JSON.stringify([null, {}, 1, fav]));
+    localStorage.setItem("mj.watched", JSON.stringify([null, fav]));
+    const trip = { id: "x", kind: "one-way", outbound: journey, savedAt: 1 };
+    localStorage.setItem(
+      "mj.trips",
+      JSON.stringify([
+        null,
+        {},
+        { ...trip, outbound: { ...journey, legs: undefined } },
+        { ...trip, outbound: { ...journey, date: "2026-10-1" } },
+        { ...trip, kind: "tour", tour: {} },
+        { ...trip, inbound: { ...journey, hubs: undefined } },
+        trip,
+      ]),
+    );
+    expect(loadFavorites()).toEqual([fav]);
+    expect(loadWatched()).toEqual([fav]);
+    expect(loadTrips()).toEqual([trip]);
+  });
+
+  it("still opens the app", () => {
+    localStorage.setItem("mj.favorites", "[null]");
+    localStorage.setItem("mj.watched", "[{}]");
+    localStorage.setItem("mj.trips", '[{"id":"t","kind":"tour","outbound":{},"tour":{}}]');
+    const root = setup(`?mode=from&from=${P}&date=2026-06-25`);
+    expect(root.querySelectorAll(".group-card").length).toBeGreaterThan(0);
+  });
+});
+
+describe("station names in a link (L3)", () => {
+  it("resolves case- and accent-insensitive names to the id the data uses", () => {
+    const registry = new StationRegistry(stations as Station[]);
+    registry.addMissing(["PARIS (intramuros)", "LILLE (intramuros)", "MARSEILLE ST CHARLES"]);
+    expect(registry.resolve("paris")).toBe("PARIS (intramuros)");
+    expect(registry.resolve("LILLE")).toBe("LILLE (intramuros)");
+    expect(registry.resolve("marseille saint-charles")).toBe("MARSEILLE ST CHARLES");
+    expect(registry.resolve("FOOBAR")).toBeUndefined();
+  });
+
+  it("shows the trains of a lower-case link and writes the ids back", () => {
+    const root = setup("?mode=od&from=paris&to=lyon&date=2026-06-25&lang=en");
+    expect(root.textContent).not.toContain(en.res_none);
+    const url = new URLSearchParams(location.search);
+    expect([url.get("from"), url.get("to")]).toEqual(["PARIS (intramuros)", "LYON (intramuros)"]);
+  });
+
+  it("picks the station with trains when the registry also has a bare id", () => {
+    const rows = (sample as RawRecord[]).map((r) =>
+      r.destination === "LILLE" ? { ...r, destination: "LILLE (intramuros)" } : r,
+    );
+    const root = setup(`?mode=od&from=${P}&to=LILLE&date=2026-06-25&lang=en`, rows);
+    expect(root.textContent).not.toContain(en.res_none);
+    expect(new URLSearchParams(location.search).get("to")).toBe("LILLE (intramuros)");
+  });
+
+  it("says a name matching no station is unknown", () => {
+    const root = setup(`?mode=od&from=${P}&to=FOOBAR&date=2026-06-25&lang=en`);
+    expect(root.textContent).toContain(en.err_station.replace("{station}", "FOOBAR"));
+    expect(root.textContent).not.toContain(en.res_none);
+  });
+});
+
+describe("the boot error card", () => {
+  it("does not blame the data when the page itself fails to open", async () => {
+    vi.resetModules();
+    vi.doMock("../src/data/dataset", () => ({ loadDataset: () => Promise.resolve({ trains: [], meta }) }));
+    vi.doMock("../src/app", () => ({
+      initApp: () => {
+        throw new Error("boom");
+      },
+    }));
+    vi.doMock("../src/pwa/register", () => ({ registerServiceWorker: () => {} }));
+    vi.doMock("../src/native/capacitor", () => ({ initNative: () => Promise.resolve() }));
+    vi.spyOn(console, "error").mockImplementation(() => {});
+    document.body.innerHTML = '<div id="app"></div>';
+    Object.defineProperty(navigator, "language", { value: "en-US", configurable: true });
+    await import("../src/main");
+    await vi.waitFor(() => expect(document.querySelector(".error-title")).not.toBeNull());
+    expect(document.querySelector(".error-title")?.textContent).toBe(en.err_app);
+  });
+});