// tests/hash.test.js

const { hashEvent, hashChain, sha256Async } = require('../lib/hash.js');

describe('Hash', () => {
  test('hashEvent returns consistent hash', () => {
    const event = { id: 'e1', type: 'tool_use' };
    const h1 = hashEvent(event);
    const h2 = hashEvent(event);
    expect(h1).toBe(h2);
    expect(h1.length).toBeGreaterThan(0);
  });

  test('hashEvent returns different hash for different events', () => {
    const h1 = hashEvent({ id: 'e1', type: 'tool_use' });
    const h2 = hashEvent({ id: 'e2', type: 'api_call' });
    expect(h1).not.toBe(h2);
  });

  test('hashChain returns empty for empty array', () => {
    expect(hashChain([])).toBe('');
  });

  test('hashChain returns hash for events', () => {
    const chain = hashChain([{ id: 'e1' }, { id: 'e2' }]);
    expect(chain.length).toBeGreaterThan(0);
  });

  test('hashChain is order-sensitive', () => {
    const chain1 = hashChain([{ id: 'e1' }, { id: 'e2' }]);
    const chain2 = hashChain([{ id: 'e2' }, { id: 'e1' }]);
    expect(chain1).not.toBe(chain2);
  });

  test('sha256Async returns hex string', async () => {
    const hash = await sha256Async('hello');
    expect(hash).toMatch(/^[a-f0-9]{64}$/);
  });
});