import type { TenantId } from "@suaveplan/api-types/tenant";
import { describe, expect, it } from "@suaveplan/testing/runner";
import { createSubscriptionBus } from "./subscription-bus.js";

const T = (s: string): TenantId => s as TenantId;

describe("subscription-bus", () => {
    it("delivers an envelope to every matching subscriber", async () => {
        const bus = createSubscriptionBus();
        const seen: string[] = [];
        bus.subscribe("audit", T("acme"), async (env) => {
            seen.push(`a:${env.event.id}`);
        });
        bus.subscribe("audit", T("acme"), async (env) => {
            seen.push(`b:${env.event.id}`);
        });
        const n = await bus.broadcast({
            topic: "audit",
            tenantId: T("acme"),
            event: { id: "1", data: "x" },
        });
        expect(n).toBe(2);
        expect(seen).toEqual(["a:1", "b:1"]);
        expect(bus.size).toBe(2);
    }, 5000);

    it("filters out envelopes when filter returns false", async () => {
        const bus = createSubscriptionBus();
        const seen: string[] = [];
        bus.subscribe(
            "audit",
            T("acme"),
            async (env) => {
                seen.push(env.event.id);
            },
            (env) => env.event.id === "2"
        );
        await bus.broadcast({
            topic: "audit",
            tenantId: T("acme"),
            event: { id: "1", data: "skip" },
        });
        await bus.broadcast({
            topic: "audit",
            tenantId: T("acme"),
            event: { id: "2", data: "ok" },
        });
        expect(seen).toEqual(["2"]);
    }, 5000);

    it("unsubscribe removes the subscriber + cleans empty keys", async () => {
        const bus = createSubscriptionBus();
        const off = bus.subscribe("audit", T("acme"), async () => undefined);
        off();
        // second invocation must be no-op (covers the "missing key" guard)
        off();
        const n = await bus.broadcast({
            topic: "audit",
            tenantId: T("acme"),
            event: { id: "1", data: "x" },
        });
        expect(n).toBe(0);
        expect(bus.size).toBe(0);
    }, 5000);

    it("unsubscribe one of many leaves the key intact", () => {
        const bus = createSubscriptionBus();
        const offA = bus.subscribe("audit", T("acme"), async () => undefined);
        bus.subscribe("audit", T("acme"), async () => undefined);
        offA();
        expect(bus.size).toBe(1);
    }, 5000);

    it("returns 0 for broadcasts with no subscribers", async () => {
        const bus = createSubscriptionBus();
        const n = await bus.broadcast({
            topic: "none",
            tenantId: T("acme"),
            event: { id: "1", data: "x" },
        });
        expect(n).toBe(0);
    }, 5000);

    it("dispose clears every subscription", async () => {
        const bus = createSubscriptionBus();
        bus.subscribe("a", T("acme"), async () => undefined);
        bus.subscribe("b", T("acme"), async () => undefined);
        expect(bus.size).toBe(2);
        bus.dispose();
        expect(bus.size).toBe(0);
    }, 5000);
});