import assert from "node:assert/strict";
import { test } from "node:test";
import { InflightTracker, type FeedEvent } from "../src/lib/inflight-tracker";

test("snapshot rebuilds counts for all in-flight requests", () => {
  const tracker = new InflightTracker();
  tracker.apply({
    type: "inflight",
    operation: "snapshot",
    requests: [
      { model: "A", id: "1" },
      { model: "A", id: "2" },
      { model: "B", id: "3" },
    ],
  });
  assert.equal(tracker.count("A"), 2);
  assert.equal(tracker.count("B"), 1);
  assert.equal(tracker.count("C"), 0);
});

test("add (upsert) is idempotent per request id", () => {
  const tracker = new InflightTracker();
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }] });
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }] });
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "2" }] });
  assert.equal(tracker.count("A"), 2);
});

test("remove is id-based and decrements the matching request", () => {
  const tracker = new InflightTracker();
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }, { model: "B", id: "2" }] });
  assert.equal(tracker.count("A"), 1);
  assert.equal(tracker.count("B"), 1);
  tracker.apply({ type: "inflight", operation: "remove", id: "1" });
  assert.equal(tracker.count("A"), 0);
  assert.equal(tracker.count("B"), 1);
  tracker.apply({ type: "inflight", operation: "remove", id: "999" });
  assert.equal(tracker.count("B"), 1);
});

test("snapshot replaces prior in-flight state", () => {
  const tracker = new InflightTracker();
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }] });
  tracker.apply({ type: "inflight", operation: "snapshot", requests: [{ model: "A", id: "2" }] });
  assert.equal(tracker.count("A"), 1);
  assert.equal(tracker.count("B"), 0);
});

test("modelStatus normalizes states", () => {
  const tracker = new InflightTracker();
  tracker.apply({
    type: "modelStatus",
    models: [
      { id: "A", state: "ready" },
      { id: "B", state: "loading" },
      { id: "C", state: "stopped" },
      { id: "D", state: "weird" },
    ],
  });
  assert.equal(tracker.state("A"), "ready");
  assert.equal(tracker.state("B"), "loading");
  assert.equal(tracker.state("C"), "stopped");
  assert.equal(tracker.state("D"), "stopped");
  assert.equal(tracker.state("missing"), undefined);
});

test("total sums in-flight requests across all models", () => {
  const tracker = new InflightTracker();
  assert.equal(tracker.total(), 0);
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }, { model: "B", id: "2" }] });
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "3" }] });
  assert.equal(tracker.total(), 3);
  tracker.apply({ type: "inflight", operation: "remove", id: "1" });
  assert.equal(tracker.total(), 2);
});

test("prune drops request ids that stopped receiving updates", () => {
  let now = 0;
  const tracker = new InflightTracker(() => now);
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }] });
  now = 200_000;
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "2" }] });
  tracker.prune(60_000);
  assert.equal(tracker.total(), 1);
  assert.equal(tracker.count("A"), 1);
});

test("active requests refreshed by upserts survive pruning", () => {
  let now = 0;
  const tracker = new InflightTracker(() => now);
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }] });
  now = 200_000;
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "1" }] });
  tracker.prune(60_000);
  assert.equal(tracker.total(), 1);
});

test("prune is applied on every inflight event", () => {
  let now = 0;
  const tracker = new InflightTracker(() => now);
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "A", id: "stale" }] });
  now = 200_000;
  tracker.apply({ type: "inflight", operation: "add", requests: [{ model: "B", id: "live" }] });
  assert.equal(tracker.total(), 1);
  assert.equal(tracker.count("B"), 1);
});