import { test } from "node:test";
import assert from "node:assert/strict";
import { parseScenario } from "../src/declaration/parse.ts";
import { planPlacements, PLACEABLE, isPlaceable } from "../src/lifecycle/place.ts";
import { assertSupported, UnsupportedError } from "../src/lifecycle/supported.ts";

/**
 * `place:` is the seam where the lab stops being infrastructure with no consumer. Each test
 * names what it defends, per novox/hq ADR 0017.
 */

function scenario(place: string): ReturnType<typeof parseScenario> {
  return parseScenario(`
scenario: placing
segments:
  hosting:
    kind: public
    cidr: [192.0.2.0/24]
machines:
  anchor:
    at: { segment: hosting, address: [192.0.2.10] }
  peer:
    at: { segment: hosting, address: [192.0.2.20] }
${place}
`);
}

test("`all:` reaches every machine", () => {
  const placements = planPlacements(scenario("place:\n  all: [host]"));
  assert.deepEqual(
    placements.map((p) => p.machine).sort(),
    ["anchor", "peer"],
  );
  for (const p of placements) assert.deepEqual(p.artifacts, ["host"]);
});

test("a per-machine entry OVERRIDES `all:`, it does not add to it", () => {
  // Worth being exact about: a scenario naming one artifact for one machine gets that
  // artifact, not that artifact plus everything in `all:`. The opposite reading would place
  // things nobody asked for, which is the shape of fault this lab exists to catch.
  const placements = planPlacements(scenario("place:\n  all: [host]\n  anchor: [substrate]"));
  const byMachine = new Map(placements.map((p) => [p.machine, p.artifacts]));

  assert.deepEqual(byMachine.get("anchor"), ["substrate"], "anchor should have ONLY substrate");
  assert.deepEqual(byMachine.get("peer"), ["host"]);
});

test("a machine placed with nothing is not a placement", () => {
  const placements = planPlacements(scenario("place:\n  all: [host]\n  anchor: []"));
  assert.deepEqual(placements.map((p) => p.machine), ["peer"]);
});

test("no `place:` at all is no placements, not an error", () => {
  assert.deepEqual(planPlacements(scenario("")), []);
});

test("placing the host is supported", () => {
  // The whole point of stage 1: this used to be refused.
  assert.doesNotThrow(() => assertSupported(scenario("place:\n  all: [host]")));
});

test("a tier that does not exist is refused BY NAME", () => {
  // Named individually rather than refused as a whole, so a scenario placing a host and a
  // substrate is told exactly which half the lab cannot do — rather than being told `place:`
  // is unsupported when half of it now works.
  try {
    assertSupported(scenario("place:\n  all: [host, substrate]\n  peer: [control]"));
    assert.fail("expected a refusal");
  } catch (err) {
    assert.ok(err instanceof UnsupportedError);
    const missing = err.missing.join("\n");
    assert.match(missing, /substrate/, "the substrate was not named");
    assert.match(missing, /control/, "the control plane was not named");
    assert.doesNotMatch(missing, /place: host/, "the host is placeable and was refused anyway");
  }
});

test("the refusal says what CAN be placed", () => {
  // A refusal that does not say what is possible sends someone to the source to find out.
  try {
    assertSupported(scenario("place:\n  all: [forge]"));
    assert.fail("expected a refusal");
  } catch (err) {
    assert.ok(err instanceof UnsupportedError);
    for (const placeable of PLACEABLE) {
      assert.match(err.missing.join("\n"), new RegExp(placeable));
    }
  }
});

// --- runtime and image placement (novox/hq ADR 0006: the lab places what a sealed scenario
//     cannot fetch) ---

test("an image reference is placeable, and a bare 'image:' is not", () => {
  assert.ok(isPlaceable("image:alpine@sha256:abc"), "a reference should be placeable");
  assert.ok(isPlaceable("image:postgres:17"), "a tag is the scenario's business, not the lab's");
  assert.ok(!isPlaceable("image:"), "there is nothing to place");
  assert.ok(!isPlaceable("image:   "), "whitespace is not a reference");
});

test("the placeables are host, runtime and an image", () => {
  assert.ok(isPlaceable("host"));
  assert.ok(isPlaceable("runtime"));
  assert.ok(!isPlaceable("substrate"), "the tiers above tier 0 do not exist yet");
  assert.ok(!isPlaceable("control-plane"));
});

test("an unplaceable artifact is named, not refused as a whole", () => {
  // A scenario placing a host and a substrate is told which half the lab cannot do — refusing
  // wholesale would send somebody looking for the wrong problem.
  const scenario = {
    name: "s",
    segments: {},
    machines: { a: {} as never },
    place: { a: ["host", "runtime", "image:alpine@sha256:x", "substrate"] },
  } as unknown as Parameters<typeof assertSupported>[0];

  assert.throws(
    () => assertSupported(scenario),
    (err: Error) => {
      // Checked as `place: <artifact> —`, which is how an artifact is REPORTED as
      // unplaceable. Searching for the bare word matched the message's own list of what CAN
      // be placed, which mentions runtime — so the test failed on a correct message.
      assert.ok(err.message.includes("place: substrate —"), "the unplaceable one is named");
      assert.ok(!err.message.includes("place: image:alpine"), "a placeable one is not");
      assert.ok(!err.message.includes("place: runtime —"), "nor is runtime");
      assert.ok(!err.message.includes("place: host —"), "nor is host");
      return true;
    },
  );
});