import {
  assertPerformanceSurveyBrowserSourceImageDimensions,
  PERFORMANCE_SURVEY_BROWSER_SOURCE_LIMITS,
  readPerformanceSurveySourceImageDimensions,
  TASK_DETAIL_BROWSER_SOURCE_MAX_PIXELS,
} from '@/lib/performance-survey-image-source-guard'

function pngHeader(width: number, height: number) {
  const bytes = new Uint8Array(24)
  bytes.set([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a])
  const view = new DataView(bytes.buffer)
  view.setUint32(16, width)
  view.setUint32(20, height)
  return bytes
}

function jpegHeader(width: number, height: number) {
  return new Uint8Array([
    0xff, 0xd8, 0xff, 0xc0, 0x00, 0x11, 0x08,
    (height >> 8) & 0xff, height & 0xff,
    (width >> 8) & 0xff, width & 0xff,
    0x03, 0x01, 0x11, 0x00, 0x02, 0x11, 0x00, 0x03, 0x11, 0x00,
  ])
}

describe('performance survey browser source image guard', () => {
  test('在解码前读取 PNG 与 JPG 尺寸', () => {
    expect(readPerformanceSurveySourceImageDimensions(pngHeader(1200, 3200))).toEqual({ width: 1200, height: 3200 })
    expect(readPerformanceSurveySourceImageDimensions(jpegHeader(1600, 4800))).toEqual({ width: 1600, height: 4800 })
  })

  test('拒绝超宽或超像素源图，不进入浏览器解码', () => {
    expect(() => assertPerformanceSurveyBrowserSourceImageDimensions(
      { width: PERFORMANCE_SURVEY_BROWSER_SOURCE_LIMITS.maxWidth + 1, height: 100 },
      'too-wide.png',
    )).toThrow('图片「too-wide.png」宽度超过 12000px')
    expect(() => assertPerformanceSurveyBrowserSourceImageDimensions(
      { width: 10000, height: 12001 },
      'too-many-pixels.png',
    )).toThrow('像素总量超过 120,000,000')
  })

  test('保留 1600px 长图，并在解码前按最终切片数量限制超长图片', () => {
    expect(() => assertPerformanceSurveyBrowserSourceImageDimensions(
      { width: 1600, height: 75_000 },
      'long-design.png',
    )).not.toThrow()
    expect(() => assertPerformanceSurveyBrowserSourceImageDimensions(
      { width: 1, height: 90_001 },
      'too-tall.png',
    )).toThrow('处理后需要 61 张切片')
  })

  test('任务详情像素门禁与服务器 Edge 兜底的 60M 限制一致', () => {
    const dimensions = { width: 10_000, height: 7_000 }
    expect(() => assertPerformanceSurveyBrowserSourceImageDimensions(
      dimensions,
      'performance-survey.png',
    )).not.toThrow()
    expect(() => assertPerformanceSurveyBrowserSourceImageDimensions(
      dimensions,
      'task-detail.png',
      { maxPixels: TASK_DETAIL_BROWSER_SOURCE_MAX_PIXELS },
    )).toThrow('像素总量超过 60,000,000')
  })
})