import { describe, it, expect, afterEach } from 'vitest';
import { envFlagEnabled } from '../env-flag';

const NAME = 'ENV_FLAG_TEST_TRUSTED_INGRESS';

afterEach(() => {
  delete process.env[NAME];
});

describe('envFlagEnabled', () => {
  it('is false when unset', () => {
    expect(envFlagEnabled(NAME)).toBe(false);
  });

  it('is false for empty / whitespace-only values', () => {
    for (const raw of ['', '   ', '\t\n']) {
      process.env[NAME] = raw;
      expect(envFlagEnabled(NAME)).toBe(false);
    }
  });

  // The whole reason this predicate is shared: a producer using bare
  // `Boolean(process.env.X)` read every one of these as ENABLED, so an
  // operator typing `=0` to mean "off" got attacker-writable IP headers
  // trusted anyway.
  it('is false for explicit off values, case- and whitespace-insensitively', () => {
    for (const raw of ['0', 'false', 'off', 'FALSE', 'Off', '  0  ', ' OFF ']) {
      process.env[NAME] = raw;
      expect(envFlagEnabled(NAME)).toBe(false);
    }
  });

  it('is true for any other non-empty value', () => {
    for (const raw of ['1', 'true', 'TRUE', 'on', 'yes', ' 1 ']) {
      process.env[NAME] = raw;
      expect(envFlagEnabled(NAME)).toBe(true);
    }
  });

  it('reads process.env per call, never module-hoisted', () => {
    expect(envFlagEnabled(NAME)).toBe(false);
    process.env[NAME] = '1';
    expect(envFlagEnabled(NAME)).toBe(true);
    process.env[NAME] = '0';
    expect(envFlagEnabled(NAME)).toBe(false);
  });

  it('is reachable from the ./chat-protocol barrel', async () => {
    const barrel = await import('../index');
    expect(barrel.envFlagEnabled).toBe(envFlagEnabled);
  });
});