// tests/main/update-policy.test.ts
// 업데이트 정책 순수 로직 테스트: 버전 비교, 메이저/증분 판단, 강제 업데이트,
// 채널 게이팅, staged rollout.

import { describe, it, expect } from 'vitest'
import {
  DEFAULT_UPDATE_POLICY,
  compareVersions,
  decideUpdate,
  isChannelAcceptable,
  isWithinRollout,
  parseUpdatePolicy,
  rolloutBucket,
  type UpdatePolicy,
} from '../../src/main/update-policy'
import { channelMetadataName, isUpdateChannel } from '../../src/main/update-feed'

const policy: UpdatePolicy = {
  ...DEFAULT_UPDATE_POLICY,
  minimumSupportedVersion: '1.0.0',
  forceInstallBelow: '0.3.0',
  fullInstallOnMajorChange: true,
  fullInstallVersionGap: 3,
  stagingPercentage: 100,
}

describe('compareVersions', () => {
  it('주/부/패치를 순서대로 비교한다', () => {
    expect(compareVersions('1.2.3', '1.2.3')).toBe(0)
    expect(compareVersions('1.2.3', '1.2.4')).toBe(-1)
    expect(compareVersions('1.3.0', '1.2.9')).toBe(1)
    expect(compareVersions('2.0.0', '1.99.99')).toBe(1)
  })

  it('prerelease는 같은 코어의 stable보다 낮다', () => {
    expect(compareVersions('1.0.0-alpha', '1.0.0')).toBe(-1)
    expect(compareVersions('1.1.0-beta.2', '1.1.0-beta.10')).toBe(-1)
  })

  it('v 접두와 build metadata를 허용한다', () => {
    expect(compareVersions('v1.1.0', '1.1.0+build.7')).toBe(0)
  })

  it('파싱 실패 시 null', () => {
    expect(compareVersions('not-a-version', '1.0.0')).toBeNull()
  })
})

describe('decideUpdate', () => {
  it('최소 지원 버전 미만이면 강제 업데이트', () => {
    const decision = decideUpdate(policy, '0.5.0', '1.1.0')
    expect(decision.mandatory).toBe(true)
    expect(decision.reason).toBe('below-minimum-supported')
  })

  it('forceInstallBelow 미만이면 강제 사유가 force-install (더 강한 조건이 우선)', () => {
    const decision = decideUpdate(policy, '0.2.1-alpha', '1.1.0')
    expect(decision.mandatory).toBe(true)
    expect(decision.reason).toBe('below-force-install')
  })

  it('최소 지원 이상이면 일반 업데이트', () => {
    const decision = decideUpdate(policy, '1.1.0', '1.2.0')
    expect(decision.mandatory).toBe(false)
    expect(decision.reason).toBe('standard')
    expect(decision.forceFull).toBe(false)
  })

  it('major 승격이면 full 다운로드', () => {
    const decision = decideUpdate(policy, '1.9.0', '2.0.0')
    expect(decision.forceFull).toBe(true)
    expect(decision.mandatory).toBe(false)
  })

  it('minor 갭이 임계 이상이면 full 다운로드', () => {
    const decision = decideUpdate(policy, '1.0.0', '1.5.0')
    expect(decision.forceFull).toBe(true)
  })

  it('major 정책이 꺼져 있으면 major 승격도 차분 가능', () => {
    const relaxed = { ...policy, fullInstallOnMajorChange: false }
    expect(decideUpdate(relaxed, '1.9.0', '2.0.0').forceFull).toBe(false)
  })

  it('현재 버전을 파싱할 수 없으면 전체 설치', () => {
    expect(decideUpdate(policy, 'garbage', '1.2.0').forceFull).toBe(true)
  })
})

describe('isChannelAcceptable', () => {
  it('stable 채널은 prerelease를 받지 않는다', () => {
    expect(isChannelAcceptable(false, '1.0.0', '1.1.0-beta')).toBe(false)
    expect(isChannelAcceptable(false, '1.0.0', '1.1.0')).toBe(true)
  })

  it('beta 채널은 prerelease를 받는다', () => {
    expect(isChannelAcceptable(true, '1.0.0', '1.1.0-beta')).toBe(true)
  })

  it('더 높은 버전이 아니면 거부한다', () => {
    expect(isChannelAcceptable(false, '1.2.0', '1.1.0')).toBe(false)
  })
})

describe('staged rollout', () => {
  it('deviceId에 대해 결정적 버킷을 돌려준다', () => {
    expect(rolloutBucket('device-a', '1.1.0')).toBe(rolloutBucket('device-a', '1.1.0'))
    expect(rolloutBucket('device-a', '1.1.0')).toBeLessThan(100)
  })

  it('100%는 모두 포함, 0%는 모두 제외', () => {
    const standard = { mandatory: false, forceFull: false, reason: 'standard' as const }
    expect(isWithinRollout({ ...policy, stagingPercentage: 100 }, 'd', '1.1.0', standard)).toBe(true)
    expect(isWithinRollout({ ...policy, stagingPercentage: 0 }, 'd', '1.1.0', standard)).toBe(false)
  })

  it('강제 업데이트는 rollout을 무시한다', () => {
    const forced = { mandatory: true, forceFull: true, reason: 'below-force-install' as const }
    expect(isWithinRollout({ ...policy, stagingPercentage: 0 }, 'd', '1.1.0', forced)).toBe(true)
  })
})

describe('parseUpdatePolicy', () => {
  it('유효한 필드를 반영하고 잘못된 필드는 기본값 유지', () => {
    const parsed = parseUpdatePolicy({
      schemaVersion: 1,
      defaultChannel: 'beta',
      minimumSupportedVersion: '1.2.0',
      forceInstallBelow: null,
      fullInstallOnMajorChange: false,
      fullInstallVersionGap: 5,
      stagingPercentage: 250,
      killSwitch: true,
      channels: { latest: { allowPrerelease: false }, rogue: {} },
    })
    expect(parsed.defaultChannel).toBe('beta')
    expect(parsed.minimumSupportedVersion).toBe('1.2.0')
    expect(parsed.forceInstallBelow).toBeNull()
    expect(parsed.fullInstallOnMajorChange).toBe(false)
    expect(parsed.fullInstallVersionGap).toBe(5)
    expect(parsed.stagingPercentage).toBe(100)
    expect(parsed.killSwitch).toBe(true)
    expect(parsed.channels.beta.allowPrerelease).toBe(DEFAULT_UPDATE_POLICY.channels.beta.allowPrerelease)
  })

  it('잘못된 입력은 기본 정책', () => {
    expect(parseUpdatePolicy(null)).toEqual(DEFAULT_UPDATE_POLICY)
    expect(parseUpdatePolicy('nope')).toEqual(DEFAULT_UPDATE_POLICY)
  })
})

describe('update-feed helpers', () => {
  it('채널별 metadata 파일명', () => {
    expect(channelMetadataName('latest')).toBe('latest.yml')
    expect(channelMetadataName('beta')).toBe('beta.yml')
    expect(channelMetadataName('alpha')).toBe('alpha.yml')
  })

  it('채널 식별', () => {
    expect(isUpdateChannel('latest')).toBe(true)
    expect(isUpdateChannel('canary')).toBe(false)
  })
})