import test from 'node:test';
import assert from 'node:assert/strict';
import monitorModule from '../src/main/repository-monitor.cjs';

const { RepositoryMonitor } = monitorModule;

test('repository monitor establishes a baseline and emits only on later changes', async () => {
  let revision = 1;
  const changes = [];
  const git = {
    status: async (localPath) => ({ localPath, revision }),
    statusFingerprint: (status) => String(status.revision)
  };
  const store = { data: { preferences: { autoRefresh: true, repositoryPollSeconds: 2 } } };
  const monitor = new RepositoryMonitor({ store, git, onChange: (change) => changes.push(change) });
  monitor.setPaths(['/repo']);
  await monitor.tick();
  assert.equal(changes.length, 0);
  revision = 2;
  await monitor.tick();
  assert.equal(changes.length, 1);
  assert.equal(changes[0].reason, 'working-tree-changed');
  monitor.pause('/repo');
  revision = 3;
  await monitor.tick();
  assert.equal(changes.length, 1);
  monitor.resume('/repo');
  await monitor.tick();
  assert.equal(changes.length, 2);
});
test('repository monitor checks multiple repositories concurrently with a bounded worker pool', async () => {
  let active = 0;
  let peak = 0;
  const git = {
    status: async (localPath) => {
      active += 1;
      peak = Math.max(peak, active);
      await new Promise((resolve) => setTimeout(resolve, 15));
      active -= 1;
      return { localPath, revision: 1 };
    },
    statusFingerprint: (status) => String(status.revision)
  };
  const store = { data: { preferences: { autoRefresh: true, repositoryPollSeconds: 2 } } };
  const monitor = new RepositoryMonitor({ store, git });
  monitor.setPaths(Array.from({ length: 10 }, (_, index) => `/repo-${index}`));
  await monitor.tick();
  assert.equal(peak, 4);
  assert.equal(active, 0);
  assert.equal(monitor.fingerprints.size, 10);
});

test('a watched repository is read on filesystem activity instead of on every interval', async (context) => {
  const { mkdtemp, mkdir, writeFile, rm } = await import('node:fs/promises');
  const os = await import('node:os');
  const path = await import('node:path');
  const root = await mkdtemp(path.join(os.tmpdir(), 'forgeflow-watch-'));
  context.after(() => rm(root, { recursive: true, force: true }));
  await mkdir(path.join(root, '.git'), { recursive: true });

  let revision = 1;
  const reads = [];
  const changes = [];
  const git = {
    status: async (localPath) => { reads.push(localPath); return { localPath, revision }; },
    statusFingerprint: (status) => String(status.revision)
  };
  const store = { data: { preferences: { autoRefresh: true, repositoryPollSeconds: 2 } } };
  const monitor = new RepositoryMonitor({ store, git, onChange: (change) => changes.push(change) });
  context.after(() => monitor.stop());

  monitor.restart();
  monitor.setPaths([root]);
  if (!monitor.watchers.has(root)) {
    context.skip('this platform does not support recursive directory watching');
    return;
  }

  await monitor.tick();
  assert.equal(reads.length, 1, 'the baseline is established once');

  // Without filesystem activity the interval must not spawn another read.
  await monitor.tick();
  assert.equal(reads.length, 1);

  revision = 2;
  await writeFile(path.join(root, 'feature.txt'), 'changed\n');
  // The watcher debounce and the per-repository cooldown both apply here.
  const deadline = Date.now() + 5_000;
  while (changes.length === 0 && Date.now() < deadline) {
    await new Promise((resolve) => setTimeout(resolve, 100));
  }

  assert.ok(reads.length > 1, 'filesystem activity triggers a read');
  assert.equal(changes.length, 1);
  assert.equal(changes[0].reason, 'working-tree-changed');

  const readsAfterChange = reads.length;
  await new Promise((resolve) => setTimeout(resolve, 800));
  assert.equal(reads.length, readsAfterChange, 'a quiet repository is not read again');

  monitor.stop();
  assert.equal(monitor.watchers.size, 0, 'stopping releases every watcher');
});

test('background Gitea awareness fetches read-only remote state with bounded concurrency', async () => {
  let active = 0;
  let peak = 0;
  const changes = [];
  const git = {
    fetch: async (localPath) => {
      active += 1;
      peak = Math.max(peak, active);
      await new Promise((resolve) => setTimeout(resolve, 15));
      active -= 1;
      return { status: { localPath, revision: 2, branch: { head: 'main', ahead: 0, behind: 1 }, counts: {} } };
    },
    statusFingerprint: (status) => String(status.revision),
  };
  const store = { data: { preferences: { autoRefresh: true, repositoryPollSeconds: 2, fetchIntervalMinutes: 1 } } };
  const monitor = new RepositoryMonitor({ store, git, onChange: (change) => changes.push(change) });
  const paths = Array.from({ length: 6 }, (_, index) => `/repo-${index}`);
  monitor.setPaths(paths);
  for (const localPath of paths) {
    monitor.fingerprints.set(localPath, '1');
    monitor.lastFetchedAt.set(localPath, Date.now() - 61_000);
  }

  await monitor.fetchRemoteUpdates();
  assert.equal(peak, 2);
  assert.equal(active, 0);
  assert.equal(changes.length, paths.length);
  assert.ok(changes.every((change) => change.reason === 'remote-state-changed'));
});

test('a zero remote fetch interval disables background network access', async () => {
  let fetches = 0;
  const git = {
    fetch: async () => { fetches += 1; return { status: { revision: 2 } }; },
    statusFingerprint: (status) => String(status.revision),
  };
  const store = { data: { preferences: { autoRefresh: true, repositoryPollSeconds: 2, fetchIntervalMinutes: 0 } } };
  const monitor = new RepositoryMonitor({ store, git });
  monitor.setPaths(['/repo']);
  monitor.lastFetchedAt.set('/repo', 0);
  await monitor.fetchRemoteUpdates(Date.now() + 24 * 60 * 60_000);
  assert.equal(fetches, 0);
});