/** @jest-environment node */

import {
  readPerformanceSurveyWebpDimensions,
  validatePerformanceSurveyProcessedImages,
} from '@/lib/performance-survey-processed-images'

function record(overrides: Record<string, unknown> = {}) {
  return {
    uploadId: 'upload-1',
    mimeType: 'image/webp',
    width: 1600,
    height: 1500,
    kind: 'slice',
    sourceName: '详情长图.png',
    sourceIndex: 0,
    sliceIndex: 0,
    sliceCount: 1,
    ...overrides,
  }
}

function vp8xHeader(width: number, height: number) {
  const buffer = Buffer.alloc(30)
  buffer.write('RIFF', 0, 'ascii')
  buffer.write('WEBP', 8, 'ascii')
  buffer.write('VP8X', 12, 'ascii')
  buffer.writeUIntLE(width - 1, 24, 3)
  buffer.writeUIntLE(height - 1, 27, 3)
  return buffer
}

describe('performance survey processed image contract', () => {
  test('accepts one optional preview plus ordered slices from one long source', () => {
    const groups = validatePerformanceSurveyProcessedImages([
      record({ uploadId: 'slice-2', sliceIndex: 1, sliceCount: 2, height: 800 }),
      record({ uploadId: 'preview', kind: 'preview', width: 720, height: 560, sliceCount: 2 }),
      record({ uploadId: 'slice-1', sliceIndex: 0, sliceCount: 2 }),
    ])

    expect(groups).toHaveLength(1)
    expect(groups[0].preview?.uploadId).toBe('preview')
    expect(groups[0].slices.map((item) => item.uploadId)).toEqual(['slice-1', 'slice-2'])
  })

  test('accepts pre-cut files as independent source groups without previews', () => {
    const groups = validatePerformanceSurveyProcessedImages([
      record({ uploadId: 'part-1', sourceName: '1.webp' }),
      record({ uploadId: 'part-2', sourceName: '2.webp', sourceIndex: 1 }),
    ])

    expect(groups).toHaveLength(2)
    expect(groups.every((group) => group.preview === null && group.sliceCount === 1)).toBe(true)
  })

  test('rejects missing or duplicated slice positions', () => {
    expect(() => validatePerformanceSurveyProcessedImages([
      record({ uploadId: 'slice-1', sliceIndex: 0, sliceCount: 2 }),
      record({ uploadId: 'slice-duplicate', sliceIndex: 0, sliceCount: 2 }),
    ])).toThrow('切片序号不连续')
  })

  test('limits final ordered slices to 60 per work item', () => {
    const sixtySlices = Array.from({ length: 60 }, (_, index) => record({
      uploadId: `long-${index}`,
      sliceIndex: index,
      sliceCount: 60,
    }))
    expect(validatePerformanceSurveyProcessedImages(sixtySlices)[0].slices).toHaveLength(60)

    expect(() => validatePerformanceSurveyProcessedImages([
      ...sixtySlices,
      record({ uploadId: 'part-61', sourceName: '2.webp', sourceIndex: 1 }),
    ])).toThrow('最多上传 60 张有序切片')
  })

  test('requires safe WebP dimensions declared by the browser', () => {
    expect(() => validatePerformanceSurveyProcessedImages([
      record({ mimeType: 'image/png' }),
    ])).toThrow('只接受 WebP')
    expect(() => validatePerformanceSurveyProcessedImages([
      record({ height: 1501 }),
    ])).toThrow('图片高度无效')
  })

  test('reads VP8X dimensions without decoding image pixels', () => {
    expect(readPerformanceSurveyWebpDimensions(vp8xHeader(1600, 900))).toEqual({ width: 1600, height: 900 })
    expect(() => readPerformanceSurveyWebpDimensions(Buffer.from('not-webp'))).toThrow('不是有效的 WebP')
  })
})