feat(reports): occupancy curve, hour×dow heatmap, stay histogram, fraud KPIs

The dashboard had generic BI views but nothing parking-shaped. Added:

- Occupancy step-area over the range with the configured capacity as a
  red reference line. occupancyStart folds the ENTIRE prior ledger
  (voided entries excluded, clamped ≥0); each series point carries
  occupancyEnd. Answers "when are we near full".
- Entries heatmap hour × day-of-week (7×24, row 0 = Monday, site tz) as
  a pure CSS-grid intensity map — weekday-vs-weekend at a glance, the
  direct evidence for tariff windows. Replaces the flat hour histogram
  (strictly contains it).
- Stay-duration histogram at tariff-shaped edges (30m/1h/2h/4h/8h/24h/
  tail): where ladder/up-to breakpoints should sit.
- Voids + anomalies KPIs (accented when >0) — the look-closer counters
  the signed chain exists for; peak-occupancy KPI (peak / capacity).
- Revenue bars stacked cash vs card (the drawer's money vs the bank's);
  CSV export gains cash, card, occupancy_end columns.

Internals: localParts caches its Intl formatter per tz (was one new
formatter per ledger row); @parking/db re-exports lt/gt. 5 new tests.

Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V

apps/server/src/reports.test.ts

@@ -181,3 +181,68 @@ describe("reportSummary — duration (sessions cache) + subscriptions", () => {
     expect(r.subscriptions.coveredCars).toBe(2);
   });
 });
+
+describe("reportSummary — occupancy, heatmap, stay histogram, look-closer counters (2026-07-05)", () => {
+  it("folds prior ledger into occupancyStart and walks occupancyEnd through the series", async () => {
+    // Before the range: 3 entries, 1 exit → 2 cars inside when June opens.
+    await entry(at("2026-05-20T08:00:00Z"));
+    await entry(at("2026-05-20T09:00:00Z"));
+    await entry(at("2026-05-21T10:00:00Z"));
+    await exit(at("2026-05-21T12:00:00Z"));
+    // In range: +2 on the 10th, −1 on the 11th.
+    await entry(at("2026-06-10T08:00:00Z"));
+    await entry(at("2026-06-10T09:00:00Z"));
+    await exit(at("2026-06-11T09:00:00Z"));
+
+    const r = reportSummary(db, { ...RANGE, bucket: "day" });
+    expect(r.occupancyStart).toBe(2);
+    expect(r.series.map((p) => [p.bucket, p.occupancyEnd])).toEqual([
+      ["2026-06-10", 4],
+      ["2026-06-11", 3],
+    ]);
+  });
+
+  it("a voided pre-range entry does not inflate occupancyStart", async () => {
+    const id = randomUUID();
+    await log.append({ type: "vehicle_entry", direction: "entry", identity: id, occurredAt: at("2026-05-20T08:00:00Z") });
+    await log.append({ type: "void", identity: id, occurredAt: at("2026-05-20T08:05:00Z"), payload: { reason: "misprint" } });
+    const r = reportSummary(db, { ...RANGE, bucket: "day" });
+    expect(r.occupancyStart).toBe(0);
+  });
+
+  it("entriesByDowHour lands on the local weekday/hour (row 0 = Monday)", async () => {
+    // 2026-06-10 is a WEDNESDAY; 08:00Z = 10:00 in Tirane (UTC+2 in June).
+    await entry(at("2026-06-10T08:00:00Z"));
+    const r = reportSummary(db, { ...RANGE, bucket: "day" });
+    expect(r.entriesByDowHour[2]![10]).toBe(1); // Wed row, 10h column
+    expect(r.entriesByDowHour.flat().reduce((a, b) => a + b, 0)).toBe(1);
+  });
+
+  it("stay histogram buckets closed sessions; series carries the cash/card split", async () => {
+    db.insert(sessions).values({ id: "h1", identity: "h1", enteredAt: at("2026-06-10T08:00:00Z"), exitedAt: at("2026-06-10T08:20:00Z"), state: "closed" }).run(); // 20m → ≤30
+    db.insert(sessions).values({ id: "h2", identity: "h2", enteredAt: at("2026-06-10T08:00:00Z"), exitedAt: at("2026-06-10T09:30:00Z"), state: "closed" }).run(); // 90m → ≤120
+    db.insert(sessions).values({ id: "h3", identity: "h3", enteredAt: at("2026-06-08T08:00:00Z"), exitedAt: at("2026-06-10T09:00:00Z"), state: "closed" }).run(); // 2 days → >24h tail
+    await payment(at("2026-06-10T09:00:00Z"), 500, { tender: "cash" });
+    await payment(at("2026-06-10T09:30:00Z"), 700, { tender: "card" });
+
+    const r = reportSummary(db, { ...RANGE, bucket: "day" });
+    const counts = Object.fromEntries(r.stayHistogram.map((b) => [String(b.uptoMin), b.count]));
+    expect(counts["30"]).toBe(1);
+    expect(counts["120"]).toBe(1);
+    expect(counts["null"]).toBe(1);
+    const day = r.series.find((p) => p.bucket === "2026-06-10")!;
+    expect(day.cashMinor).toBe(500);
+    expect(day.cardMinor).toBe(700);
+  });
+
+  it("counts voids and anomalies in range (the look-closer counters)", async () => {
+    const id = randomUUID();
+    await log.append({ type: "vehicle_entry", direction: "entry", identity: id, occurredAt: at("2026-06-10T08:00:00Z") });
+    await log.append({ type: "void", identity: id, occurredAt: at("2026-06-10T08:05:00Z"), payload: { reason: "misprint" } });
+    await log.append({ type: "anomaly", identity: "X", occurredAt: at("2026-06-10T09:00:00Z"), payload: { reason: "test" } });
+    const r = reportSummary(db, { ...RANGE, bucket: "day" });
+    expect(r.totals.voids).toBe(1);
+    expect(r.totals.anomalies).toBe(1);
+    expect(r.totals.entries).toBe(0); // the voided entry stays excluded
+  });
+});

apps/server/src/reports.ts

@@ -4,9 +4,11 @@ import {
   desc,
   eq,
   gte,
+  lt,
   lte,
   ledgerEvents,
   sessions,
+  siteConfig,
   subscriptions,
   tariffVersions,
   tariffs,
@@ -46,8 +48,13 @@ export interface SeriesPoint {
   readonly exits: number;
   /** Net transient revenue collected in the bucket (minor units), all tenders. */
   readonly revenueMinor: number;
+  /** Tender split of the bucket's revenue (cash = everything not card). */
+  readonly cashMinor: number;
+  readonly cardMinor: number;
   /** Payment COUNT in the bucket (transactions, not amount). */
   readonly payments: number;
+  /** Cars inside at the END of the bucket (occupancyStart + running entries−exits). */
+  readonly occupancyEnd: number;
 }
 
 export interface ReportTotals {
@@ -67,6 +74,10 @@ export interface ReportTotals {
   readonly totalParkedMinutes: number;
   readonly avgParkedMinutes: number;
   readonly medianParkedMinutes: number;
+  /** Cancelled tickets + signed anomalies in range — the "look closer" counters
+   *  (the operator at the booth is the threat model's primary adversary). */
+  readonly voids: number;
+  readonly anomalies: number;
 }
 
 export interface SubscriptionStats {
@@ -79,6 +90,13 @@ export interface SubscriptionStats {
   readonly coveredCars: number;
 }
 
+/** One bar of the stay-duration histogram: stays up to `uptoMin` minutes (null = the
+ *  open-ended tail). Edges chosen to mirror how tariffs are designed (see tariff.md). */
+export interface StayBucket {
+  readonly uptoMin: number | null;
+  readonly count: number;
+}
+
 export interface ReportSummary {
   readonly from: string;
   readonly to: string;
@@ -89,25 +107,43 @@ export interface ReportSummary {
   readonly series: SeriesPoint[];
   /** Entries by local hour-of-day (0–23), summed across the range — the peak-hour view. */
   readonly entriesByHour: number[];
+  /** Entries by [day-of-week][hour-of-day] — 7×24, row 0 = Monday. The heatmap that
+   *  shows weekday-vs-weekend patterns (feeds tariff-window design). */
+  readonly entriesByDowHour: number[][];
+  /** Stay-duration histogram over closed sessions in range. */
+  readonly stayHistogram: StayBucket[];
+  /** Cars inside when the range OPENS (folded from the whole prior ledger). */
+  readonly occupancyStart: number;
+  /** Nominal capacity from site config (null = uncapped) — the reference line. */
+  readonly capacity: number | null;
   readonly subscriptions: SubscriptionStats;
 }
 
 /** Local wall-clock parts of an ISO instant in a given IANA tz. Reuses Intl (no dep). */
-function localParts(iso: string, tz: string): { y: number; mo: number; d: number; h: number } {
-  const fmt = new Intl.DateTimeFormat("en-CA", {
-    timeZone: tz,
-    year: "numeric",
-    month: "2-digit",
-    day: "2-digit",
-    hour: "2-digit",
-    hourCycle: "h23",
-  });
+const fmtCache = new Map<string, Intl.DateTimeFormat>();
+const DOW_INDEX: Record<string, number> = { Mon: 0, Tue: 1, Wed: 2, Thu: 3, Fri: 4, Sat: 5, Sun: 6 };
+function localParts(iso: string, tz: string): { y: number; mo: number; d: number; h: number; dow: number } {
+  // Cached per tz — this runs once per ledger row in a report.
+  let fmt = fmtCache.get(tz);
+  if (!fmt) {
+    fmt = new Intl.DateTimeFormat("en-US", {
+      timeZone: tz,
+      year: "numeric",
+      month: "2-digit",
+      day: "2-digit",
+      hour: "2-digit",
+      hourCycle: "h23",
+      weekday: "short",
+    });
+    fmtCache.set(tz, fmt);
+  }
   const parts = Object.fromEntries(fmt.formatToParts(new Date(iso)).map((p) => [p.type, p.value]));
   return {
     y: Number(parts.year),
     mo: Number(parts.month),
     d: Number(parts.day),
     h: Number(parts.hour),
+    dow: DOW_INDEX[parts.weekday ?? ""] ?? 0, // row 0 = Monday
   };
 }
 
@@ -162,6 +198,7 @@ export function reportSummary(db: Db, q: ReportQuery): ReportSummary {
 
   const seriesMap = new Map<string, SeriesPoint>();
   const entriesByHour = new Array<number>(24).fill(0);
+  const entriesByDowHour = Array.from({ length: 7 }, () => new Array<number>(24).fill(0));
   const totals = {
     entries: 0,
     exits: 0,
@@ -172,12 +209,14 @@ export function reportSummary(db: Db, q: ReportQuery): ReportSummary {
     ticketMinor: 0,
     subscriptionSalesMinor: 0,
     subscriptionWindowMinor: 0,
+    voids: 0,
+    anomalies: 0,
   };
 
   function point(label: string): SeriesPoint {
     let p = seriesMap.get(label);
     if (!p) {
-      p = { bucket: label, entries: 0, exits: 0, revenueMinor: 0, payments: 0 };
+      p = { bucket: label, entries: 0, exits: 0, revenueMinor: 0, cashMinor: 0, cardMinor: 0, payments: 0, occupancyEnd: 0 };
       seriesMap.set(label, p);
     }
     return p;
@@ -196,11 +235,16 @@ export function reportSummary(db: Db, q: ReportQuery): ReportSummary {
       if (row.identity && voided.has(row.identity)) continue; // cancelled — not a real entry
       totals.entries++;
       p.entries++;
-      const h = localParts(row.occurredAt, tz).h;
-      entriesByHour[h] = (entriesByHour[h] ?? 0) + 1;
+      const lp = localParts(row.occurredAt, tz);
+      entriesByHour[lp.h] = (entriesByHour[lp.h] ?? 0) + 1;
+      entriesByDowHour[lp.dow]![lp.h] = (entriesByDowHour[lp.dow]![lp.h] ?? 0) + 1;
     } else if (row.type === "vehicle_exit") {
       totals.exits++;
       p.exits++;
+    } else if (row.type === "void") {
+      totals.voids++;
+    } else if (row.type === "anomaly") {
+      totals.anomalies++;
     } else if (row.type === "payment") {
       const pl = (row.payload ?? {}) as PaymentPayload;
       const amt = typeof pl.amountMinor === "number" ? pl.amountMinor : 0;
@@ -209,8 +253,13 @@ export function reportSummary(db: Db, q: ReportQuery): ReportSummary {
       totals.revenueMinor += amt;
       p.payments++;
       p.revenueMinor += amt;
-      if (pl.tender === "card") totals.cardMinor += amt;
-      else totals.cashMinor += amt;
+      if (pl.tender === "card") {
+        totals.cardMinor += amt;
+        p.cardMinor += amt;
+      } else {
+        totals.cashMinor += amt;
+        p.cashMinor += amt;
+      }
       // Revenue split mirrors the shift Z-report: subscription sale / window charge /
       // (the rest is) transient ticket revenue.
       if (pl.subscriptionSale === true) totals.subscriptionSalesMinor += amt;
@@ -221,6 +270,31 @@ export function reportSummary(db: Db, q: ReportQuery): ReportSummary {
 
   const series = [...seriesMap.values()].sort((a, b) => a.bucket.localeCompare(b.bucket));
 
+  // --- Occupancy: fold the PRIOR ledger for cars-inside at range start, then walk the
+  // series. Voided pre-range entries cancel out the same way the in-range pass does.
+  // Sparse buckets (no events) simply carry the previous level — the step line is exact
+  // at every plotted point.
+  const prior = db
+    .select({ type: ledgerEvents.type, identity: ledgerEvents.identity })
+    .from(ledgerEvents)
+    .where(lt(ledgerEvents.occurredAt, q.from))
+    .all();
+  const priorVoided = new Set<string>();
+  for (const r of prior) if (r.type === "void" && r.identity) priorVoided.add(r.identity);
+  let occupancyStart = 0;
+  for (const r of prior) {
+    if (r.type === "vehicle_entry" && !(r.identity && priorVoided.has(r.identity))) occupancyStart++;
+    else if (r.type === "vehicle_exit") occupancyStart--;
+  }
+  occupancyStart = Math.max(0, occupancyStart);
+  let running = occupancyStart;
+  for (const p of series) {
+    running = Math.max(0, running + p.entries - p.exits);
+    (p as { -readonly [K in keyof SeriesPoint]: SeriesPoint[K] }).occupancyEnd = running;
+  }
+
+  const capacity = db.select().from(siteConfig).where(eq(siteConfig.id, 1)).get()?.capacity ?? null;
+
   // No payment in range? Fall back to the site tariff's latest version currency, so a
   // zero-revenue range still labels its money column.
   if (!currency) {
@@ -251,6 +325,19 @@ export function reportSummary(db: Db, q: ReportQuery): ReportSummary {
   durations.sort((a, b) => a - b);
   const totalParkedMinutes = durations.reduce((a, b) => a + b, 0);
 
+  // Stay-duration histogram. Edges mirror how rate cards are designed (30m/1h bands,
+  // the 8h working day, the 24h rolling day) so the chart answers "where should the
+  // ladder/up-to breakpoints sit". Last bucket is the open-ended >24h tail.
+  const STAY_EDGES_MIN = [30, 60, 120, 240, 480, 1440];
+  const stayHistogram: { uptoMin: number | null; count: number }[] = [
+    ...STAY_EDGES_MIN.map((uptoMin) => ({ uptoMin, count: 0 })),
+    { uptoMin: null, count: 0 },
+  ];
+  for (const mins of durations) {
+    const i = STAY_EDGES_MIN.findIndex((edge) => mins <= edge);
+    stayHistogram[i === -1 ? STAY_EDGES_MIN.length : i]!.count++;
+  }
+
   // --- Subscriptions: status counts + currently-valid (window covers `to`).
   const subs = db.select().from(subscriptions).all();
   const subStats = { active: 0, suspended: 0, revoked: 0, currentlyValid: 0, coveredCars: 0 };
@@ -283,6 +370,10 @@ export function reportSummary(db: Db, q: ReportQuery): ReportSummary {
     },
     series,
     entriesByHour,
+    entriesByDowHour,
+    stayHistogram,
+    occupancyStart,
+    capacity,
     subscriptions: subStats,
   };
 }

apps/server/src/routes/reports.ts

@@ -48,9 +48,18 @@ export async function reportRoutes(app: FastifyInstance, db: Db): Promise<void>
     async (req, reply) => {
       const summary = reportSummary(db, parseQuery(req.query));
       const lines = [
-        "bucket,entries,exits,payments,revenue",
+        "bucket,entries,exits,payments,revenue,cash,card,occupancy_end",
         ...summary.series.map((p) =>
-          [p.bucket, p.entries, p.exits, p.payments, (p.revenueMinor / 100).toFixed(2)].join(","),
+          [
+            p.bucket,
+            p.entries,
+            p.exits,
+            p.payments,
+            (p.revenueMinor / 100).toFixed(2),
+            (p.cashMinor / 100).toFixed(2),
+            (p.cardMinor / 100).toFixed(2),
+            p.occupancyEnd,
+          ].join(","),
         ),
       ];
       reply