import test from 'node:test';
import assert from 'node:assert/strict';
import { createHash } from 'node:crypto';
import { appendFileSync, mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { dirname, join } from 'node:path';
import { git, migrationManifest } from '../lib.mjs';

function fixture(t) {
  const cwd = mkdtempSync(join(tmpdir(), 'fedeo-migrations-test-'));
  t.after(() => rmSync(cwd, { recursive: true, force: true }));
  const run = args => git(args, cwd, { stdio: ['pipe', 'pipe', 'pipe'] });
  run(['init', '-b', 'main']);
  run(['config', 'user.name', 'Release Test']);
  run(['config', 'user.email', 'release@example.test']);
  // Keep CRLF test bytes in Git regardless of the developer's autocrlf setting.
  writeFileSync(join(cwd, '.gitattributes'), '*.sql -text\n');
  const write = (path, data) => {
    mkdirSync(dirname(join(cwd, path)), { recursive: true });
    writeFileSync(join(cwd, path), data);
  };
  const commit = () => {
    run(['add', '.']);
    run(['commit', '--allow-empty', '-m', 'test: add migrations']);
    return run(['rev-parse', 'HEAD']);
  };
  return { cwd, run, write, commit };
}

test('large migration hashes use the complete committed bytes beyond process buffer limits', async t => {
  const f = fixture(t);
  const path = 'backend/db/migrations/0058_reference_data.sql';
  f.write(path, '');
  const expected = createHash('sha256');
  const chunk = Buffer.alloc(1024 * 1024, Buffer.from("  INSERT INTO reference VALUES ('Grüße');\r\n"));
  // Exceed both Node's 1 MiB default and the text Git helper's 32 MiB buffer.
  for (let i = 0; i < 34; i++) {
    appendFileSync(join(f.cwd, path), chunk);
    expected.update(chunk);
  }
  const sha = f.commit();
  f.write(path, 'local changes must not affect the release checksum');
  assert.deepEqual(await migrationManifest(sha, f.cwd), [{ path, sha256: expected.digest('hex') }]);
});

test('both migration folders are hashed byte-for-byte and non-SQL files are excluded', async t => {
  const f = fixture(t);
  const files = [
    ['backend/db/migrations/0000_init.sql', Buffer.from(' \r\nSELECT 1;\r\n\t')],
    ['push-server/packages/db/drizzle/0000_init.sql', Buffer.from('SELECT \'äöü\';\n')],
  ];
  for (const [path, content] of files) f.write(path, content);
  f.write('backend/db/migrations/meta/snapshot.json', '{}');
  const sha = f.commit();
  assert.deepEqual(await migrationManifest(sha, f.cwd), files.map(([path, content]) => ({
    path, sha256: createHash('sha256').update(content).digest('hex'),
  })));
});

test('a commit without migration folders produces an empty manifest', async t => {
  const f = fixture(t);
  assert.deepEqual(await migrationManifest(f.commit(), f.cwd), []);
});

test('an unreadable Git blob rejects the manifest instead of recording a partial checksum', async t => {
  const f = fixture(t);
  const path = 'backend/db/migrations/0000_missing.sql';
  f.write(path, 'SELECT 1;');
  const sha = f.commit();
  const blob = f.run(['rev-parse', `${sha}:${path}`]);
  rmSync(join(f.cwd, '.git', 'objects', blob.slice(0, 2), blob.slice(2)));
  await assert.rejects(async () => migrationManifest(sha, f.cwd), /0000_missing\.sql/);
});