import test from "node:test";
import assert from "node:assert/strict";
import { mkdtemp, readFile, rm, stat, utimes, access } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { loadModule } from "./test-helpers.mjs";

const { DropStore, DropStoreError, pathsFor } = await loadModule(
  "server/utils/drop-store.ts",
);
const { CHUNK_SIZE } = await loadModule("shared/types/drop.ts");
const noncePrefix = "AQIDBAUGBwg";
let roots = [];
async function fresh(clock = { now: () => Date.now() }) {
  const root = await mkdtemp(join(tmpdir(), "quickdrop-test-"));
  roots.push(root);
  return { store: new DropStore({ root, clock }), root };
}
async function reserve(store, maxReads = 1, expiresIn = "24h") {
  return store.reserve({
    version: 2,
    chunkSize: CHUNK_SIZE,
    chunkCount: 1,
    noncePrefix,
    expiresIn,
    maxReads,
  });
}
async function ready(store, maxReads = 1, expiresIn = "24h") {
  const result = await reserve(store, maxReads, expiresIn);
  await store.putChunk(result.id, 0, new Uint8Array(16));
  await store.finalize(result.id, new Uint8Array(17));
  return result;
}
async function exists(path) {
  try {
    await access(path);
    return true;
  } catch {
    return false;
  }
}
test.after(async () => {
  await Promise.all(
    roots.map((root) => rm(root, { recursive: true, force: true })),
  );
});

test("finalize starts expiry and rejects missing chunks", async () => {
  let now = 1000;
  const { store } = await fresh({ now: () => now });
  const result = await reserve(store, 1, "1h");
  await assert.rejects(
    store.finalize(result.id, new Uint8Array(17)),
    (error) => error instanceof DropStoreError && error.code === "incomplete",
  );
  await store.putChunk(result.id, 0, new Uint8Array(16));
  const metadata = await store.finalize(result.id, new Uint8Array(17));
  assert.equal(metadata.expiresAt, now + 3600000);
  now += 3599999;
  assert.equal(
    (await store.descriptor(result.id, result.access)).id,
    result.id,
  );
  now++;
  await assert.rejects(
    store.descriptor(result.id, result.access),
    (error) => error instanceof DropStoreError && error.code === "expired",
  );
});

test("chunk retries are idempotent and conflicting contents are rejected", async () => {
  const { store } = await fresh();
  const result = await reserve(store);
  const body = new Uint8Array(16).fill(7);
  assert.equal(await store.putChunk(result.id, 0, body), "created");
  assert.equal(await store.putChunk(result.id, 0, body), "same");
  await assert.rejects(
    store.putChunk(result.id, 0, new Uint8Array(16).fill(8)),
    (error) => error instanceof DropStoreError && error.code === "conflict",
  );
});

test("maxReads claims are serialized, valid lease reuse does not increment, and completion cleans up", async () => {
  const { store, root } = await fresh();
  const result = await ready(store, 1);
  const claims = await Promise.allSettled([
    store.claim(result.id, result.access),
    store.claim(result.id, result.access),
  ]);
  assert.equal(
    claims.filter((value) => value.status === "fulfilled").length,
    1,
  );
  assert.equal(claims.filter((value) => value.status === "rejected").length, 1);
  const first = claims.find((value) => value.status === "fulfilled").value;
  const metadataBefore = await store.readMetadata(result.id);
  const reused = await store.claim(result.id, result.access, first.token);
  assert.equal(reused.reused, true);
  assert.equal(
    (await store.readMetadata(result.id)).readsClaimed,
    metadataBefore.readsClaimed,
  );
  const chunk = await store.readChunk(result.id, 0, first.token);
  assert.equal(chunk.size, 16);
  await chunk.handle.close();
  await store.complete(result.id, first.token);
  assert.equal(await exists(pathsFor(result.id, root).directory), false);
});

test("unlimited drops allow multiple leases and metadata remains parseable", async () => {
  const { store, root } = await fresh();
  const result = await ready(store, null);
  const one = await store.claim(result.id, result.access);
  const two = await store.claim(result.id, result.access);
  assert.notEqual(one.token, two.token);
  assert.equal((await store.readMetadata(result.id)).readsClaimed, 2);
  JSON.parse(await readFile(pathsFor(result.id, root).metadata, "utf8"));
  await store.complete(result.id, one.token);
  assert.equal(await exists(pathsFor(result.id, root).directory), true);
});

test("idle lease cleanup and stale temporary files are safe", async () => {
  let now = 100000;
  const { store, root } = await fresh({ now: () => now });
  const result = await ready(store, 1);
  await store.claim(result.id, result.access);
  const paths = pathsFor(result.id, root);
  const stale = join(paths.directory, ".chunk-stale");
  await (await import("node:fs/promises")).writeFile(stale, "stale");
  const old = new Date(now - 2 * 3600000);
  await utimes(stale, old, old);
  now += 16 * 60 * 1000;
  await store.cleanup();
  assert.equal(await exists(stale), false);
  assert.equal(await exists(paths.directory), false);
});

test("metadata-less valid directories are removed only after grace period", async () => {
  let now = 10_000_000;
  const { store, root } = await fresh({ now: () => now });
  const result = await reserve(store);
  const paths = pathsFor(result.id, root);
  await rm(paths.metadata);
  const recent = new Date(now);
  await utimes(paths.directory, recent, recent);
  await store.cleanup();
  assert.equal(await exists(paths.directory), true);
  const old = new Date(now - 2 * 3600000);
  await utimes(paths.directory, old, old);
  await store.cleanup();
  assert.equal(await exists(paths.directory), false);
});