import { afterEach, beforeEach, describe, expect, it } from "vitest";
import { createTestDb } from "@parking/db/testing";
import { ledgerEvents, deviceEvents as deviceEventsTable, sessions as sessionsTable, eq, type Db } from "@parking/db";
import { randomUUID } from "node:crypto";
import { ExitFlow } from "./exit-flow.js";
import { PayStation } from "./pay-station.js";
import type { EventLog } from "./event-log.js";
import { makeLog, silentLogger, seedTariff, minutesAgo } from "./test-helpers.js";

// The exit flow is the anti-fraud GATE: no car leaves without a covering payment within
// the walk-back grace (the no-unpaid-bypass + no-free-overstay rules), and the booth has
// no bypass. With no relay configured a clean exit returns { opened:false } — we assert
// the DECISION (refuse vs. sign the exit), not the hardware open.

let db: Db;
let close: () => void;
let log: EventLog;
let exit: ExitFlow;
let pay: PayStation;

beforeEach(() => {
  const t = createTestDb();
  db = t.db;
  close = t.close;
  log = makeLog(db);
  exit = new ExitFlow(db, log, silentLogger());
  pay = new PayStation(db, log, silentLogger());
});
afterEach(() => close());

async function enter(identity: string, enteredAt: string, payload?: Record<string, unknown>) {
  await log.append({ type: "vehicle_entry", direction: "entry", identity, occurredAt: enteredAt, payload: payload ?? null });
}
function exitsSigned(identity: string) {
  return db.select().from(ledgerEvents).where(eq(ledgerEvents.identity, identity)).all().filter((r) => r.type === "vehicle_exit");
}
function anomalies(reason?: string) {
  return db.select().from(ledgerEvents).where(eq(ledgerEvents.type, "anomaly")).all()
    .filter((r) => !reason || (r.payload as { reason?: string } | null)?.reason?.includes(reason));
}
/** Seed the projection-cache open-session row + an ANPR plate read (device_events) so the
 *  plate-reconciliation check can see this identity's plate against open sessions. */
function seedOpenWithPlate(identity: string, plate: string, confidence: number, enteredAt: string) {
  db.insert(sessionsTable).values({ id: identity, identity, source: "ticket", enteredAt, state: "open" }).run();
  db.insert(deviceEventsTable).values({
    id: randomUUID(), deviceId: "cam-entry", category: "camera", kind: "read", occurredAt: enteredAt,
    detail: { identity, direction: "entry", plate, confidence },
  }).run();
}

describe("exitForBooth — refusal gates", () => {
  it("refuses an unknown ticket (no session) and signs an anomaly", async () => {
    const r = await exit.exitForBooth("ghost");
    expect(r).toMatchObject({ ok: false, status: "no_session" });
    const anomalies = db.select().from(ledgerEvents).where(eq(ledgerEvents.type, "anomaly")).all();
    expect(anomalies).toHaveLength(1);
    expect(exitsSigned("ghost")).toHaveLength(0);
  });

  it("refuses an UNPAID open session — no exit signed (no-unpaid-bypass)", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000 });
    await enter("T1", minutesAgo(90));
    const r = await exit.exitForBooth("T1");
    expect(r).toMatchObject({ ok: false, status: "unpaid" });
    expect(exitsSigned("T1")).toHaveLength(0); // the car did NOT leave
  });

  it("refuses a paid session whose walk-back grace has EXPIRED (no free overstay)", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000, gracePeriodExitMin: 15 });
    await enter("T1", minutesAgo(200));
    // A payment made 60 min ago → its 15-min walk-back grace lapsed long ago.
    await log.append({
      type: "payment", source: "manual", identity: "T1", occurredAt: minutesAgo(60),
      payload: { sessionRef: "T1", amountMinor: 10000, currency: "ALL", tender: "cash", graceExitMin: 15 },
    });
    const r = await exit.exitForBooth("T1");
    expect(r).toMatchObject({ ok: false, status: "grace_expired" });
    expect(exitsSigned("T1")).toHaveLength(0);
  });
});

describe("exitForBooth — valid exit signs the vehicle_exit", () => {
  it("a paid session within grace signs an exit (opened:false — no relay in tests)", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000, gracePeriodExitMin: 15 });
    await enter("T1", minutesAgo(90));
    await pay.pay("T1", "cash"); // fresh payment → within grace
    const r = await exit.exitForBooth("T1");
    expect(r.ok).toBe(true);
    if (r.ok) expect(r.opened).toBe(false); // signed, but no barrier resolves in tests
    expect(exitsSigned("T1")).toHaveLength(1); // the exit IS on the chain
    expect(log.verifyChain()).toEqual({ ok: true });
  });

  // NB: a subscriber's normal exit runs through SubscriptionFlow (the reader/credential
  // path), not exitForBooth — the booth's transient exit has no subscription bypass and
  // applies the same paid/grace gate to any identity it's handed. Asserting that here so
  // the boundary is explicit: handing a bare occurrence to exitForBooth is refused, and a
  // subscriber leaves via reopenBarrier (assist) or the subscription reader flow instead.
  it("does NOT give the booth transient-exit path a subscription bypass", async () => {
    await enter("SUBSESS-1", minutesAgo(30), { permit: true, permitId: "sub-1" });
    const r = await exit.exitForBooth("SUBSESS-1");
    expect(r).toMatchObject({ ok: false, status: "unpaid" });
    expect(exitsSigned("SUBSESS-1")).toHaveLength(0);
  });

  it("lets a prepaid subscriber out via the assist (reopenBarrier) path", async () => {
    await enter("SUBSESS-1", minutesAgo(30), { permit: true, permitId: "sub-1" });
    const r = await exit.reopenBarrier("SUBSESS-1", "op1");
    expect(r.ok).toBe(true);
    expect(exitsSigned("SUBSESS-1")).toHaveLength(1); // assist closes the open occurrence
  });
});

describe("reopenBarrier — no unpaid re-open", () => {
  it("refuses to re-open an unpaid transient session", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000 });
    await enter("T1", minutesAgo(90));
    const r = await exit.reopenBarrier("T1", "op1");
    expect(r.ok).toBe(false);
    expect(exitsSigned("T1")).toHaveLength(0);
  });

  it("re-opening a paid OPEN session also closes it (signs the exit)", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000, gracePeriodExitMin: 15 });
    await enter("T1", minutesAgo(90));
    await pay.pay("T1", "cash");
    const r = await exit.reopenBarrier("T1", "op1");
    expect(r.ok).toBe(true);
    // The open session is closed by the human-intervention exit so it leaves the list.
    expect(exitsSigned("T1")).toHaveLength(1);
  });
});

describe("exitForBooth — plate-swap reconciliation (ticket-swap fraud)", () => {
  // The fraud: a paid car is let out on a fresh $0 ticket while the original lingers "inside".
  // The plate is the invariant — the exiting car's plate is already open under the old ticket.
  it("HOLDS a paid exit when the plate is already open under a DIFFERENT ticket", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000, gracePeriodExitMin: 15 });
    // Original car entered on 1234, plate AA123BB, still open (never paid/exited).
    await enter("1234", minutesAgo(120));
    seedOpenWithPlate("1234", "AA123BB", 0.99, minutesAgo(120));
    // A fresh ticket 1237 (same physical car, same plate) is paid and tries to exit.
    await enter("1237", minutesAgo(1));
    seedOpenWithPlate("1237", "AA123BB", 0.99, minutesAgo(1));
    await pay.pay("1237", "cash");

    const r = await exit.exitForBooth("1237");
    expect(r).toMatchObject({ ok: false, status: "swap_suspected", plate: "AA123BB", otherIdentity: "1234" });
    expect(exitsSigned("1237")).toHaveLength(0); // NOT let out
    expect(anomalies("plate AA123BB is already inside").length).toBeGreaterThanOrEqual(1);
  });

  it("RELEASES on explicit operator override + signs an attributed override anomaly", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000, gracePeriodExitMin: 15 });
    await enter("1234", minutesAgo(120));
    seedOpenWithPlate("1234", "AA123BB", 0.99, minutesAgo(120));
    await enter("1237", minutesAgo(1));
    seedOpenWithPlate("1237", "AA123BB", 0.99, minutesAgo(1));
    await pay.pay("1237", "cash");

    const r = await exit.exitForBooth("1237", { override: true, operator: "op1" });
    expect(r.ok).toBe(true);
    expect(exitsSigned("1237")).toHaveLength(1); // released
    const ov = anomalies("released a suspected ticket-swap");
    expect(ov.length).toBe(1);
    expect((ov[0].payload as { operator?: string }).operator).toBe("op1");
  });

  it("does NOT warn on a LOW-confidence plate read (advisory, never a gate)", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000, gracePeriodExitMin: 15 });
    await enter("1234", minutesAgo(120));
    seedOpenWithPlate("1234", "AA123BB", 0.5, minutesAgo(120)); // low conf
    await enter("1237", minutesAgo(1));
    seedOpenWithPlate("1237", "AA123BB", 0.5, minutesAgo(1)); // low conf
    await pay.pay("1237", "cash");

    const r = await exit.exitForBooth("1237");
    expect(r.ok).toBe(true); // no warning — exits normally
    expect(exitsSigned("1237")).toHaveLength(1);
  });

  it("does NOT warn a normal exit whose OWN plate is only open under its OWN ticket", async () => {
    seedTariff(db, { pricePerIncrementMinor: 10000, gracePeriodExitMin: 15 });
    await enter("1237", minutesAgo(90));
    seedOpenWithPlate("1237", "AA999ZZ", 0.99, minutesAgo(90));
    await pay.pay("1237", "cash");

    const r = await exit.exitForBooth("1237");
    expect(r.ok).toBe(true); // its own plate under its own ticket is not a swap
    expect(exitsSigned("1237")).toHaveLength(1);
  });
});