tariff composer: admin publishes rate-card versions (pay station now operable)

validateTariffStructure (shared): non-negative ints, ascending block bounds, only the last block open-ended — a malformed card can't be published. Routes: GET /api/tariff (active + history, any signed-in role), POST /api/tariff/versions (publish an immutable, effective-dated version; admin only). The single site tariff row is created lazily. Editing = publish a new version; past sessions keep their pricing. Web: TariffComposer in the admin shell — edit currency, grace windows, increment, daily cap, lost-ticket fee, and add/remove rate blocks (major-unit input -> minor on submit); shows active version + history. Verified via inject: empty -> active null; invalid blocks -> 400 with problem; valid -> 201; readonly publish -> 403; after publishing, the pay station quote returns 404 (no session) instead of 409 (no tariff) -- it now prices against the active card.
2026-06-15 19:35:33 +02:00
parent f18e28eeca
commit b4d0dfadd6
8 changed files with 412 additions and 1 deletions
@@ -0,0 +1,79 @@
+import { randomUUID } from "node:crypto";
+import type { FastifyInstance } from "fastify";
+import { desc, eq, tariffVersions, tariffs, type Db } from "@parking/db";
+import { validateTariffStructure, type TariffStructure } from "@parking/shared";
+import { requireRole } from "../auth.js";
+
+// Tariff composer API — the admin builds + edits the rate card at runtime. Tariffs
+// are EFFECTIVE-DATED IMMUTABLE VERSIONS: editing publishes a new version, never
+// mutates one; a session reprices against the version in force at its entry, and
+// the `payment` event records the tariffVersionId. "One active tariff per site" for
+// now (a single `tariffs` row, lazily created). See wiki/concepts/tariff.md.
+
+interface PublishBody {
+  currency: string;
+  structure: TariffStructure;
+  /** When this version takes effect (ISO-8601). Defaults to now. */
+  effectiveFrom?: string;
+}
+
+const SITE_TARIFF_NAME = "Site tariff";
+
+export async function tariffRoutes(app: FastifyInstance, db: Db): Promise<void> {
+  // Any signed-in role may READ the tariff (the pay station / operator UI needs it).
+  const readGuard = requireRole("admin", "operator", "cashier", "readonly");
+  // Only an admin may PUBLISH a new version (it changes what customers are charged).
+  const writeGuard = requireRole("admin");
+
+  // The single site tariff row, created on first read/publish.
+  function ensureSiteTariff(): string {
+    const existing = db.select().from(tariffs).where(eq(tariffs.scope, "site")).get();
+    if (existing) return existing.id;
+    const id = randomUUID();
+    db.insert(tariffs).values({ id, scope: "site", name: SITE_TARIFF_NAME }).run();
+    return id;
+  }
+
+  // Current state: the active (latest-effective, ≤ now) version + the full history.
+  app.get("/api/tariff", { preHandler: readGuard }, async () => {
+    const tariffId = ensureSiteTariff();
+    const versions = db
+      .select()
+      .from(tariffVersions)
+      .where(eq(tariffVersions.tariffId, tariffId))
+      .orderBy(desc(tariffVersions.effectiveFrom))
+      .all();
+    const now = new Date().toISOString();
+    const active = versions.find((v) => v.effectiveFrom <= now) ?? null;
+    return { tariffId, active, versions };
+  });
+
+  // Publish a new immutable version. Validates the structure first — a malformed
+  // rate card can never be published (the fee calc + the chain depend on it).
+  app.post<{ Body: PublishBody }>(
+    "/api/tariff/versions",
+    { preHandler: writeGuard },
+    async (req, reply) => {
+      const { currency, structure, effectiveFrom } = req.body ?? ({} as PublishBody);
+      if (!currency || typeof currency !== "string" || currency.length < 3) {
+        return reply.code(400).send({ error: "currency (ISO 4217) required" });
+      }
+      const problems = validateTariffStructure(structure);
+      if (problems.length) {
+        return reply.code(400).send({ error: "invalid tariff structure", problems });
+      }
+      const tariffId = ensureSiteTariff();
+      const id = randomUUID();
+      const row = {
+        id,
+        tariffId,
+        effectiveFrom: effectiveFrom ?? new Date().toISOString(),
+        currency,
+        structure: structure as unknown as Record<string, unknown>,
+        createdBy: req.user?.username ?? null,
+      };
+      db.insert(tariffVersions).values(row).run();
+      return reply.code(201).send(row);
+    },
+  );
+}