import { describe, expect, test } from 'bun:test'
import {
  describeProbeFailure,
  findTarget,
  isChallenge,
  judge,
  rayId,
  REACH_TARGETS,
} from './reachability.ts'

const openai = REACH_TARGETS[0]!
const gemini = REACH_TARGETS[2]!

const headers = (init: Record<string, string> = {}) => new Headers(init)

describe('REACH_TARGETS', () => {
  test('标识不重名，否则接口按 id 取目标会取错', () => {
    const ids = REACH_TARGETS.map((t) => t.id)
    expect(new Set(ids).size).toBe(ids.length)
  })

  test('findTarget 认不出来的标识返回 null', () => {
    expect(findTarget('openai')?.label).toBe('OpenAI')
    expect(findTarget('nonesuch')).toBeNull()
  })
})

describe('judge', () => {
  test('无鉴权探测拿到 401 算可达，并说明这是预期结果', () => {
    const { verdict, message } = judge(openai, 401, headers(), '')
    expect(verdict).toBe('reachable')
    expect(message).toBe('HTTP 401，目标可达')
  })

  test('2xx 不需要解释，只报状态码', () => {
    expect(judge(gemini, 200, headers(), '{}')).toEqual({
      verdict: 'reachable',
      message: 'HTTP 200',
    })
  })

  test('白名单之外的状态码算不通', () => {
    const { verdict, message } = judge(gemini, 403, headers(), '')
    expect(verdict).toBe('unreachable')
    expect(message).toBe('HTTP 403，不是预期的状态码')
  })

  test('429 单独说是限流，不和连不上混在一起', () => {
    expect(judge(openai, 429, headers(), '').verdict).toBe('throttled')
  })

  test('Cloudflare 拦截优先于状态码白名单', () => {
    // 429 在 openai 的白名单外，但结论要是 challenge 而不是 throttled：
    // 前者要换出口 IP，后者只要等
    const { verdict, message } = judge(
      openai,
      429,
      headers({ 'cf-mitigated': 'challenge', 'cf-ray': '8f0a1b2c3d4e5f60-LAX' }),
      '',
    )
    expect(verdict).toBe('challenge')
    expect(message).toContain('8f0a1b2c3d4e5f60-LAX')
  })
})

describe('isChallenge', () => {
  test('只有 403 和 429 才可能是拦截页', () => {
    const body = '<html>window._cf_chl_opt</html>'
    expect(isChallenge(403, headers(), body)).toBe(true)
    expect(isChallenge(429, headers(), body)).toBe(true)
    expect(isChallenge(200, headers(), body)).toBe(false)
  })

  test('没有 cf-mitigated 头时认正文里的标记', () => {
    expect(isChallenge(403, headers(), '<title>Just a Moment...</title>')).toBe(true)
  })

  test('普通的 403 不是拦截页', () => {
    expect(isChallenge(403, headers(), '{"error":"forbidden"}')).toBe(false)
  })

  test('正文只看前 4 KB，标记在那之后不算', () => {
    expect(isChallenge(403, headers(), 'x'.repeat(5000) + 'just a moment')).toBe(false)
  })
})

describe('rayId', () => {
  test('优先取响应头', () => {
    expect(rayId(headers({ 'cf-ray': '  abc123-LAX  ' }), 'cf-ray: zzz')).toBe('abc123-LAX')
  })

  test('没有响应头时从正文里找', () => {
    expect(rayId(headers(), 'Cloudflare Ray ID: <code>cf-ray: abc123</code>')).toBe('abc123')
  })

  test('都没有就是空串', () => {
    expect(rayId(headers(), 'nothing here')).toBe('')
  })
})

describe('describeProbeFailure', () => {
  test('超时说等了多久', () => {
    const error = new Error('timed out')
    error.name = 'TimeoutError'
    expect(describeProbeFailure(7890, 10_000, error)).toBe('10 秒内没有响应')
  })

  test('本机端口没人监听时指向内核，不照抄 Bun 那句指向目标网址的话', () => {
    const error = Object.assign(new Error('Unable to connect. Is the computer able to access the url?'), {
      code: 'ConnectionRefused',
    })
    expect(describeProbeFailure(7890, 10_000, error)).toBe('本机 7890 端口没有响应，内核可能没在运行')
  })

  test('其余原因照原文给出，不猜', () => {
    expect(describeProbeFailure(7890, 10_000, new Error('TLS handshake failed'))).toBe(
      '连接失败：TLS handshake failed',
    )
  })
})