parking_solution/apps/server/src/routes/pay.ts

import type { FastifyInstance } from "fastify";
import type { Db } from "@parking/db";
import { NoPrinterAvailableError } from "@parking/devices";
import { requireRole } from "../auth.js";
import {
  NoOpenSessionError,
  NoTariffError,
  type PayStation,
} from "../pay-station.js";
import type { ExitFlow } from "../exit-flow.js";
import { printExitVoucher } from "../booth-print.js";

// Booth endpoints (pay-on-foot): look up a session, quote it, take payment, and —
// when the booth is at/near the exit — open the barrier. The payment becomes a
// signed ledger event; PCI scope stays OUT of the app (card capture is a standalone
// P2PE terminal; `tender` just records cash vs. card). The booth exit reuses the
// SAME validation as the reader path — no booth-only bypass admits an unpaid car.
// See wiki/concepts/tariff.md, parking-session.md, booth-exit-flow.md, bom.md.

interface QuoteQuery {
  identity: string;
}
interface PayBody {
  identity: string;
  tender: "cash" | "card";
  /** Operator-set amount (lost ticket / dispute) — overrides the computed fee. */
  overrideMinor?: number;
}
interface ExitBody {
  identity: string;
}
interface VoucherBody {
  identity: string;
}

export async function payRoutes(
  app: FastifyInstance,
  db: Db,
  payStation: PayStation,
  exitFlow: ExitFlow,
): Promise<void> {
  // Cashier/operator/admin operate the booth; readonly may not.
  const guard = requireRole("admin", "operator", "cashier");

  // Active sessions for the booth list: still-open OR exited-but-within-grace
  // (barrier unconfirmed → a paid/exited car is presumed possibly-present until
  // grace expires). Read-only. See wiki/concepts/booth-exit-flow.md.
  app.get("/api/sessions/active", { preHandler: guard }, async () => ({
    sessions: payStation.activeSessions(),
  }));

  // Session lookup for the booth pay/exit modal: entry/exit times, paid state,
  // amount owed now, walk-back-grace status. Read-only (no side effect).
  app.get<{ Params: { identity: string } }>(
    "/api/session/:identity",
    { preHandler: guard },
    async (req, reply) => {
      const identity = (req.params.identity ?? "").trim();
      if (!identity) return reply.code(400).send({ error: "identity required" });
      return payStation.lookup(identity);
    },
  );

  // Booth-driven exit: validate (paid + grace, or free entry-grace) THEN sign
  // vehicle_exit + open the barrier. Maps the discriminated result to HTTP:
  //  - validation reject → 409 with a reason (operator takes payment first),
  //  - exit signed but barrier didn't open → 200 { opened:false } (payment stands;
  //    operator opens manually; an anomaly is already signed),
  //  - clean exit → 200 { opened:true }.
  app.post<{ Body: ExitBody }>(
    "/api/exit",
    { preHandler: guard },
    async (req, reply) => {
      const identity = (req.body?.identity ?? "").trim();
      if (!identity) return reply.code(400).send({ error: "identity required" });
      const res = await exitFlow.exitForBooth(identity);
      if (!res.ok) return reply.code(409).send({ error: res.reason, status: res.status });
      return reply.code(200).send(res);
    },
  );

  // Human-intervention barrier re-open for an ACTIVE (paid) session — damaged
  // ticket / dead scanner / phantom re-close. Re-pulses the exit relay + signs an
  // anomaly (attributed); NEVER a second vehicle_exit. Refused without a payment
  // (no-unpaid-bypass). See wiki/concepts/booth-exit-flow.md.
  app.post<{ Body: ExitBody }>(
    "/api/barrier/reopen",
    { preHandler: guard },
    async (req, reply) => {
      const identity = (req.body?.identity ?? "").trim();
      if (!identity) return reply.code(400).send({ error: "identity required" });
      const operator = req.user?.username;
      const res = await exitFlow.reopenBarrier(identity, operator);
      if (!res.ok) return reply.code(409).send({ error: res.reason });
      return reply.code(200).send(res);
    },
  );

  // Quote: what does this session owe right now? (No side effect.)
  app.get<{ Querystring: QuoteQuery }>(
    "/api/pay/quote",
    { preHandler: guard },
    async (req, reply) => {
      const identity = (req.query.identity ?? "").trim();
      if (!identity) return reply.code(400).send({ error: "identity required" });
      try {
        return payStation.quote(identity);
      } catch (err) {
        return mapError(reply, err);
      }
    },
  );

  // Pay: take payment and append the signed `payment` event.
  app.post<{ Body: PayBody }>(
    "/api/pay",
    { preHandler: guard },
    async (req, reply) => {
      const { identity, tender, overrideMinor } = req.body ?? {};
      if (!identity || (tender !== "cash" && tender !== "card")) {
        return reply.code(400).send({ error: "identity and tender (cash|card) required" });
      }
      if (overrideMinor != null && (!Number.isInteger(overrideMinor) || overrideMinor < 0)) {
        return reply.code(400).send({ error: "overrideMinor must be a non-negative integer (minor units)" });
      }
      try {
        const res = await payStation.pay(identity, tender, overrideMinor);
        return reply.code(201).send(res);
      } catch (err) {
        return mapError(reply, err);
      }
    },
  );

  // Print an exit voucher (the paid ticket id reprinted as a barcode) on the booth
  // printer. Used when the booth is far from the exit — the customer self-scans the
  // voucher at the exit reader, which runs the normal validated exit. Requires the
  // session to be PAID (no free vouchers for unpaid sessions). See booth-exit-flow.md.
  app.post<{ Body: VoucherBody }>(
    "/api/voucher",
    { preHandler: guard },
    async (req, reply) => {
      const identity = (req.body?.identity ?? "").trim();
      if (!identity) return reply.code(400).send({ error: "identity required" });
      const view = payStation.lookup(identity);
      if (!view.found || !view.open) {
        return reply.code(404).send({ error: "no open session for ticket" });
      }
      if (view.paidAt == null) {
        return reply.code(409).send({ error: "session not paid — take payment before printing a voucher" });
      }
      try {
        const printedBy = await printExitVoucher(db, identity, app.log);
        return reply.code(200).send({ ok: true, printedBy });
      } catch (err) {
        if (err instanceof NoPrinterAvailableError) {
          return reply.code(503).send({ error: err.message });
        }
        return reply.code(500).send({ error: (err as Error).message });
      }
    },
  );
}

function mapError(reply: import("fastify").FastifyReply, err: unknown) {
  if (err instanceof NoOpenSessionError) return reply.code(404).send({ error: err.message });
  if (err instanceof NoTariffError) return reply.code(409).send({ error: err.message });
  return reply.code(500).send({ error: (err as Error).message });
}