import { readFile } from 'node:fs/promises'
import path from 'node:path'
import process from 'node:process'
import { chromium } from '@playwright/test'

const DEFAULT_MANIFEST = 'static/guide-floor-basemaps/manifest.json'
const DEFAULT_VITE_URL = 'http://127.0.0.1:5173'
const PROJECTION_VERSION = 'ortho-yaw54-v2'
const COMPOSITION_VERSION = 'compact-floor-center-v1'
const EXPECTED_FLOOR_COUNT = 9
const EXPECTED_COMPOSITE_COUNT = 1
const GUIDE_CAMERA_YAW_DEGREES = 54
const GUIDE_CAMERA_FOV_DEGREES = 42
const OVERVIEW_CAMERA_DISTANCE = 720
const INDOOR_REFERENCE_FIT_DIMENSION = 270.39
const INDOOR_ENTRY_CAMERA_DISTANCE_FACTOR = 0.56
const OVERVIEW_MAX_DISTANCE_FACTOR = 1.35
const FLOOR_MAX_DISTANCE_FACTOR = 1.18
const OVERVIEW_SCREEN_OFFSET_RATIO_X = -0.045
const FLOOR_SCREEN_OFFSET_RATIO_X = -0.05
const GUIDE_CAMERA_TARGET = { x: 29.0598, z: 23.9424 }
const MIN_INITIAL_VIEWPORT_CSS_WIDTH = 390
const MIN_INITIAL_VIEWPORT_PIXEL_DENSITY = 1
const MAX_WEBP_BYTES = 1_500_000
const MAX_TOTAL_WEBP_BYTES = 3_000_000

const isFiniteNumber = (value) => typeof value === 'number' && Number.isFinite(value)

const verifyOrthographicProjection = (floor) => {
  const projection = floor.projection
  if (projection?.type !== 'orthographic-xz') {
    throw new Error(`${floor.floorCode}: projection must be orthographic-xz`)
  }
  if (
    !isFiniteNumber(projection.minX)
    || !isFiniteNumber(projection.maxX)
    || !isFiniteNumber(projection.minZ)
    || !isFiniteNumber(projection.maxZ)
    || !isFiniteNumber(projection.planeY)
    || !isFiniteNumber(projection.center?.x)
    || !isFiniteNumber(projection.center?.z)
    || !isFiniteNumber(projection.width)
    || !isFiniteNumber(projection.height)
    || !isFiniteNumber(projection.screenRight?.x)
    || !isFiniteNumber(projection.screenRight?.z)
    || !isFiniteNumber(projection.screenDown?.x)
    || !isFiniteNumber(projection.screenDown?.z)
    || projection.maxX <= projection.minX
    || projection.maxZ <= projection.minZ
    || projection.width <= 0
    || projection.height <= 0
  ) {
    throw new Error(`${floor.floorCode}: projection contract is invalid`)
  }
  const rightLength = Math.hypot(projection.screenRight.x, projection.screenRight.z)
  const downLength = Math.hypot(projection.screenDown.x, projection.screenDown.z)
  const basisDot = projection.screenRight.x * projection.screenDown.x
    + projection.screenRight.z * projection.screenDown.z
  if (
    Math.abs(rightLength - 1) > 1e-6
    || Math.abs(downLength - 1) > 1e-6
    || Math.abs(basisDot) > 1e-6
  ) {
    throw new Error(`${floor.floorCode}: projection basis must be normalized and orthogonal`)
  }
  const yaw = GUIDE_CAMERA_YAW_DEGREES * Math.PI / 180
  if (
    Math.abs(projection.screenRight.x - Math.cos(yaw)) > 1e-6
    || Math.abs(projection.screenRight.z + Math.sin(yaw)) > 1e-6
    || Math.abs(projection.screenDown.x - Math.sin(yaw)) > 1e-6
    || Math.abs(projection.screenDown.z - Math.cos(yaw)) > 1e-6
  ) {
    throw new Error(`${floor.floorCode}: projection basis does not match yaw ${GUIDE_CAMERA_YAW_DEGREES}`)
  }
  const projectionAspect = projection.width / projection.height
  const imageAspect = floor.image.width / floor.image.height
  if (Math.abs(projectionAspect - imageAspect) > 1e-6) {
    throw new Error(`${floor.floorCode}: projection/image aspect mismatch`)
  }

  const initial = floor.initialViewport
  if (
    !isFiniteNumber(initial?.centerX)
    || !isFiniteNumber(initial?.centerZ)
    || !isFiniteNumber(initial?.visibleWorldSpan)
    || !isFiniteNumber(initial?.maxVisibleWorldSpan)
    || initial.visibleWorldSpan <= 0
    || initial.maxVisibleWorldSpan < initial.visibleWorldSpan
  ) {
    throw new Error(`${floor.floorCode}: initialViewport is invalid`)
  }
  const isComposite = floor.role === 'SAME_GROUND_COMPOSITE'
  const isExterior = String(floor.floorCode).toUpperCase() === 'EXTERIOR'
  const isOverviewLike = isExterior || isComposite
  const distance = isOverviewLike
    ? OVERVIEW_CAMERA_DISTANCE
    : Math.abs(
      INDOOR_REFERENCE_FIT_DIMENSION
      / Math.sin((GUIDE_CAMERA_FOV_DEGREES * Math.PI / 180) / 2)
    ) * INDOOR_ENTRY_CAMERA_DISTANCE_FACTOR
  const expectedInitialSpan = 2
    * distance
    * Math.tan((GUIDE_CAMERA_FOV_DEGREES * Math.PI / 180) / 2)
    * imageAspect
  const expectedMaxSpan = expectedInitialSpan * (
    isOverviewLike ? OVERVIEW_MAX_DISTANCE_FACTOR : FLOOR_MAX_DISTANCE_FACTOR
  )
  if (
    Math.abs(initial.visibleWorldSpan - expectedInitialSpan) > 1e-6
    || Math.abs(initial.maxVisibleWorldSpan - expectedMaxSpan) > 1e-6
  ) {
    throw new Error(`${floor.floorCode}: initial viewport does not match the live GLB camera contract`)
  }

  const floorLevelMatch = /^L(-?\d+(?:\.\d+)?)$/.exec(String(floor.floorCode).toUpperCase())
  const floorLevel = floorLevelMatch ? Number(floorLevelMatch[1]) : Number.NaN
  const useCompactFloorVisualCenter = isComposite || floorLevel === 1.5 || floorLevel >= 3
  const modelCenter = {
    x: (floor.bounds.min.x + floor.bounds.max.x) / 2,
    z: (floor.bounds.min.z + floor.bounds.max.z) / 2
  }
  const baseCenter = useCompactFloorVisualCenter ? modelCenter : GUIDE_CAMERA_TARGET
  const overviewVisibleWorldSpan = 2
    * OVERVIEW_CAMERA_DISTANCE
    * Math.tan((GUIDE_CAMERA_FOV_DEGREES * Math.PI / 180) / 2)
    * imageAspect
  const horizontalScreenOffset = useCompactFloorVisualCenter
    ? FLOOR_SCREEN_OFFSET_RATIO_X * expectedInitialSpan
    : OVERVIEW_SCREEN_OFFSET_RATIO_X * overviewVisibleWorldSpan
  const expectedCenter = {
    x: baseCenter.x + projection.screenRight.x * horizontalScreenOffset,
    z: baseCenter.z + projection.screenRight.z * horizontalScreenOffset
  }
  if (
    Math.abs(initial.centerX - expectedCenter.x) > 1e-6
    || Math.abs(initial.centerZ - expectedCenter.z) > 1e-6
    || Math.abs(projection.center.x - expectedCenter.x) > 1e-6
    || Math.abs(projection.center.z - expectedCenter.z) > 1e-6
  ) {
    throw new Error(`${floor.floorCode}: projection center does not match the live GLB floor visual-center contract`)
  }
  const expectedStrategy = useCompactFloorVisualCenter
    ? 'model-box-center-with-screen-offset'
    : 'shared-overview-target-with-screen-offset'
  if (
    floor.visualCenter?.strategy !== expectedStrategy
    || Math.abs(floor.visualCenter?.base?.x - baseCenter.x) > 1e-6
    || Math.abs(floor.visualCenter?.base?.z - baseCenter.z) > 1e-6
    || Math.abs(floor.visualCenter?.horizontalScreenOffset - horizontalScreenOffset) > 1e-6
  ) {
    throw new Error(`${floor.floorCode}: visual-center metadata is invalid`)
  }

  const corners = [
    { x: floor.bounds.min.x, z: floor.bounds.min.z },
    { x: floor.bounds.min.x, z: floor.bounds.max.z },
    { x: floor.bounds.max.x, z: floor.bounds.min.z },
    { x: floor.bounds.max.x, z: floor.bounds.max.z }
  ]
  for (const point of corners) {
    const deltaX = point.x - projection.center.x
    const deltaZ = point.z - projection.center.z
    const right = deltaX * projection.screenRight.x + deltaZ * projection.screenRight.z
    const down = deltaX * projection.screenDown.x + deltaZ * projection.screenDown.z
    if (Math.abs(right) > projection.width / 2 + 1e-6 || Math.abs(down) > projection.height / 2 + 1e-6) {
      throw new Error(`${floor.floorCode}: projection coverage does not contain the model bounds`)
    }
  }

  const initialSourcePixels = floor.image.width * initial.visibleWorldSpan / projection.width
  const density = initialSourcePixels / MIN_INITIAL_VIEWPORT_CSS_WIDTH
  if (density + 1e-6 < MIN_INITIAL_VIEWPORT_PIXEL_DENSITY) {
    throw new Error(`${floor.floorCode}: initial viewport pixel density is too low (${density})`)
  }
}

const parseArgs = (argv) => {
  const values = new Map()
  for (let index = 0; index < argv.length; index += 1) {
    const argument = argv[index]
    if (argument === '--help' || argument === '-h') return { help: true, values }
    if (!argument.startsWith('--')) throw new Error(`Unknown argument: ${argument}`)
    const [key, inlineValue] = argument.slice(2).split('=', 2)
    const value = inlineValue ?? argv[index + 1]
    if (!value || value.startsWith('--')) throw new Error(`Missing value for --${key}`)
    if (inlineValue === undefined) index += 1
    if (!['manifest', 'vite-url'].includes(key)) throw new Error(`Unknown argument: --${key}`)
    values.set(key, value)
  }
  return { help: false, values }
}

const main = async () => {
  const parsed = parseArgs(process.argv.slice(2))
  if (parsed.help) {
    console.log('Usage: npm run verify:guide-floor-basemaps -- [--manifest <path>] [--vite-url <url>]')
    return
  }

  const manifestPath = path.resolve(parsed.values.get('manifest') || process.env.GUIDE_BASEMAP_MANIFEST || DEFAULT_MANIFEST)
  const viteUrl = (parsed.values.get('vite-url') || process.env.GUIDE_BASEMAP_VITE_URL || DEFAULT_VITE_URL).replace(/\/+$/, '')
  const manifest = JSON.parse(await readFile(manifestPath, 'utf8'))
  if (!Array.isArray(manifest.floors) || manifest.floors.length !== EXPECTED_FLOOR_COUNT) {
    throw new Error(`Basemap manifest must contain ${EXPECTED_FLOOR_COUNT} floor entries`)
  }
  if (!Array.isArray(manifest.routeAssets) || manifest.routeAssets.length !== EXPECTED_COMPOSITE_COUNT) {
    throw new Error(`Basemap manifest must contain ${EXPECTED_COMPOSITE_COUNT} composite route entry`)
  }
  if (
    manifest.schemaVersion !== 4
    || manifest.render?.projection !== 'orthographic-xz'
    || manifest.render?.projectionVersion !== PROJECTION_VERSION
    || manifest.render?.compositionVersion !== COMPOSITION_VERSION
  ) {
    throw new Error('Basemap manifest is not an orthographic schema v4 manifest')
  }
  const composite = manifest.routeAssets[0]
  const expectedCoverageCodes = ['EXTERIOR', 'L1']
  const expectedCoverageIds = expectedCoverageCodes.map((floorCode) => {
    const floor = manifest.floors.find((entry) => entry.floorCode === floorCode)
    if (!floor) throw new Error(`Composite coverage floor ${floorCode} is missing from ordinary floor entries`)
    return String(floor.floorId)
  })
  if (
    composite.role !== 'SAME_GROUND_COMPOSITE'
    || composite.floorCode !== 'EXTERIOR_L1'
    || !composite.assetId
    || !composite.modelUrl
    || !composite.modelVersion
    || JSON.stringify(composite.coverageFloorCodes) !== JSON.stringify(expectedCoverageCodes)
    || JSON.stringify(composite.coverageFloorIds) !== JSON.stringify(expectedCoverageIds)
  ) {
    throw new Error('EXTERIOR_L1 composite metadata or coverage does not match the SDK floor identities')
  }

  const entries = [...manifest.floors, ...manifest.routeAssets]
  for (const floor of entries) {
    verifyOrthographicProjection(floor)
    if (!/\.ortho-yaw54-v2\.compact-floor-center-v1\.webp$/i.test(String(floor.image?.path || ''))) {
      throw new Error(`${floor.floorCode}: image URL is missing the ${PROJECTION_VERSION}/${COMPOSITION_VERSION} cache identity`)
    }
  }

  const browser = await chromium.launch({ headless: true })
  const page = await browser.newPage()
  await page.goto(`${viteUrl}/`, { waitUntil: 'domcontentloaded' })
  let totalWebpBytes = 0
  try {
    for (const floor of entries) {
      const imagePath = String(floor.image?.path || '')
      const response = await page.request.get(`${viteUrl}${imagePath}`)
      if (!response.ok()) throw new Error(`${floor.floorCode}: image is unavailable at ${imagePath} (${response.status()})`)
      const bytes = await response.body()
      if (bytes.length > MAX_WEBP_BYTES) {
        throw new Error(`${floor.floorCode}: WebP exceeds the weak-network size budget (${bytes.length} bytes)`)
      }
      if (Number(floor.image?.bytes) !== bytes.length) {
        throw new Error(`${floor.floorCode}: manifest byte count does not match the WebP file`)
      }
      totalWebpBytes += bytes.length
      const inspection = await page.evaluate(async ({ base64, expectedWidth, expectedHeight }) => {
        const image = new Image()
        image.src = `data:image/webp;base64,${base64}`
        await image.decode()
        const canvas = document.createElement('canvas')
        canvas.width = image.naturalWidth
        canvas.height = image.naturalHeight
        const context = canvas.getContext('2d', { willReadFrequently: true })
        context.drawImage(image, 0, 0)
        const pixels = context.getImageData(0, 0, canvas.width, canvas.height).data
        const first = [pixels[0], pixels[1], pixels[2]]
        let differingPixels = 0
        for (let index = 0; index < pixels.length; index += 4) {
          const difference = Math.abs(pixels[index] - first[0])
            + Math.abs(pixels[index + 1] - first[1])
            + Math.abs(pixels[index + 2] - first[2])
          if (difference > 24 && pixels[index + 3] > 0) differingPixels += 1
        }
        return {
          width: image.naturalWidth,
          height: image.naturalHeight,
          differingRatio: differingPixels / (canvas.width * canvas.height),
          dimensionsMatch: image.naturalWidth === expectedWidth && image.naturalHeight === expectedHeight
        }
      }, {
        base64: bytes.toString('base64'),
        expectedWidth: floor.image.width,
        expectedHeight: floor.image.height
      })
      if (!inspection.dimensionsMatch || inspection.differingRatio < 0.003) {
        throw new Error(`${floor.floorCode}: invalid WebP (dimensionsMatch=${inspection.dimensionsMatch}, differingRatio=${inspection.differingRatio})`)
      }
      console.log(`Verified ${floor.floorCode}: ${inspection.width}x${inspection.height}, differing ratio ${inspection.differingRatio.toFixed(4)}`)
    }
    if (totalWebpBytes > MAX_TOTAL_WEBP_BYTES) {
      throw new Error(`WebP set exceeds the total weak-network budget (${totalWebpBytes} bytes)`)
    }
    console.log(`Verified ${entries.length} WebP files, total ${totalWebpBytes} bytes`)
  } finally {
    await browser.close()
  }
}

main().catch((error) => {
  console.error(error instanceof Error ? error.stack || error.message : error)
  process.exitCode = 1
})