import { describe, expect, test } from 'bun:test';
import { classifyVersionDelta, parseVersion, resolveDeployPosture } from './deploy-posture';

describe('parseVersion', () => {
  test('parses major.minor.patch+build', () => {
    expect(parseVersion('1.2.3+28')).toEqual({
      major: 1,
      minor: 2,
      patch: 3,
      prerelease: '',
      build: '28',
    });
  });

  test('parses a prerelease', () => {
    expect(parseVersion('0.5.0-alpha.9')).toEqual({
      major: 0,
      minor: 5,
      patch: 0,
      prerelease: 'alpha.9',
      build: '',
    });
  });

  test('tolerates a bare version', () => {
    expect(parseVersion('2.0.0')).toEqual({
      major: 2,
      minor: 0,
      patch: 0,
      prerelease: '',
      build: '',
    });
  });
});

describe('classifyVersionDelta (highest-order component that changed)', () => {
  test('major / minor / patch', () => {
    expect(classifyVersionDelta('1.0.0', '2.0.0')).toBe('major');
    expect(classifyVersionDelta('1.0.0', '1.1.0')).toBe('minor');
    expect(classifyVersionDelta('1.0.0', '1.0.1')).toBe('patch');
  });

  test('build-metadata-only change is a revision', () => {
    expect(classifyVersionDelta('1.0.1+27', '1.0.1+28')).toBe('revision');
  });

  test('prerelease-only change counts as patch (still fast)', () => {
    expect(classifyVersionDelta('0.5.0-alpha.8', '0.5.0-alpha.9')).toBe('patch');
  });

  test('identical versions → none', () => {
    expect(classifyVersionDelta('1.0.1+28', '1.0.1+28')).toBe('none');
  });

  test('highest-order wins when several components differ', () => {
    expect(classifyVersionDelta('1.0.1+5', '1.1.0+1')).toBe('minor');
  });
});

describe('resolveDeployPosture (precedence)', () => {
  test('default by-semver: revision + patch ⇒ fast', () => {
    expect(resolveDeployPosture({ installed: '1.0.1+1', next: '1.0.1+2' }).posture).toBe('fast');
    expect(resolveDeployPosture({ installed: '1.0.1', next: '1.0.2' }).posture).toBe('fast');
  });

  test('default by-semver: minor + major ⇒ safe', () => {
    expect(resolveDeployPosture({ installed: '1.0.0', next: '1.1.0' }).posture).toBe('safe');
    expect(resolveDeployPosture({ installed: '1.0.0', next: '2.0.0' }).posture).toBe('safe');
  });

  test('per-release deploy_posture overrides the semver default', () => {
    // a minor bump would default to safe; the release pins fast.
    const r = resolveDeployPosture({ installed: '1.0.0', next: '1.1.0', releasePosture: 'fast' });
    expect(r.posture).toBe('fast');
    expect(r.reason).toContain('release deploy_posture');
  });

  test('module always-safe is a hard floor — beats a per-release fast', () => {
    const r = resolveDeployPosture({
      installed: '1.0.1',
      next: '1.0.2',
      releasePosture: 'fast',
      modulePolicy: 'always-safe',
    });
    expect(r.posture).toBe('safe');
    expect(r.reason).toContain('always-safe');
  });

  test('module always-fast forces fast on a minor bump (when no release override)', () => {
    expect(
      resolveDeployPosture({ installed: '1.0.0', next: '1.1.0', modulePolicy: 'always-fast' })
        .posture,
    ).toBe('fast');
  });

  test('a per-release safe still beats always-fast (release intent wins below the floor)', () => {
    expect(
      resolveDeployPosture({
        installed: '1.0.1',
        next: '1.0.2',
        releasePosture: 'safe',
        modulePolicy: 'always-fast',
      }).posture,
    ).toBe('safe');
  });
});