import { render, TEXTURE_FILTER } from '../renderer'
import { hslToRgb, rgbToHsl } from '../utils'
import { Vec3 } from '../utils/math'

// const PALETTE_16: Vec3[] = [
//   [0.1498, 0.7753, 0.8255],
//   [0.1024, 0.9387, 0.6804],
//   [0.0699, 0.6976, 0.598],
//   [0.9567, 0.2212, 0.4431],
//   [0.8718, 0.2321, 0.2196],
//   [0.3833, 0.3623, 0.2706],
//   [0.2965, 0.3277, 0.4608],
//   [0.175, 0.5405, 0.5647],
//   [0.5355, 0.5341, 0.6549],
//   [0.5996, 0.368, 0.5098],
//   [0.6795, 0.134, 0.3804],
//   [0.5333, 0.1643, 0.5824],
//   [0.0764, 0.2791, 0.8314],
//   [0, 0.8324, 0.649],
//   [0.9194, 0.4819, 0.3784],
//   [0.9423, 0.7605, 0.6725]
// ]
// const BIAS_16 = 0.11

// WINDOWS 95 - 256 COLOURS PALETTE
const PALETTE_256: Vec3[] = [
  [0, 0, 0],
  [0, 1, 0.251],
  [0.3333, 1, 0.251],
  [0.1667, 1, 0.251],
  [0.6667, 1, 0.251],
  [0.8333, 1, 0.251],
  [0.5, 1, 0.251],
  [0, 0, 0.7529],
  [0.3333, 0.2857, 0.8078],
  [0.5856, 0.7115, 0.7961],
  [0.6393, 0.6038, 0.4157],
  [0.6502, 1, 0.5824],
  [0.2596, 1, 0.1863],
  [0.4686, 0.3869, 0.2686],
  [0.5977, 0.6038, 0.4157],
  [0.6252, 1, 0.5824],
  [0.2782, 1, 0.249],
  [0.4176, 0.503, 0.3314],
  [0.556, 0.6038, 0.4157],
  [0.6002, 1, 0.5824],
  [0.2893, 1, 0.3118],
  [0.3946, 0.5821, 0.3941],
  [0.5143, 0.6038, 0.4157],
  [0.5751, 1, 0.5824],
  [0.2967, 1, 0.3745],
  [0.3814, 0.6395, 0.4569],
  [0.4765, 0.6395, 0.4569],
  [0.5501, 1, 0.5824],
  [0.3019, 1, 0.4373],
  [0.3729, 0.7388, 0.5196],
  [0.4512, 0.7388, 0.5196],
  [0.525, 1, 0.5824],
  [0.3059, 1, 0.5],
  [0.367, 1, 0.5824],
  [0.4335, 1, 0.5824],
  [0.5, 1, 0.5824],
  [0, 1, 0.1667],
  [0.8333, 1, 0.1667],
  [0.75, 1, 0.3333],
  [0.7222, 1, 0.5],
  [0.0608, 1, 0.1667],
  [0.8333, 0.4655, 0.2275],
  [0.7314, 0.6915, 0.3941],
  [0.7068, 1, 0.5608],
  [0.1235, 1, 0.1667],
  [0.8333, 0.1486, 0.2902],
  [0.7009, 0.4592, 0.4569],
  [0.6858, 1, 0.6235],
  [0.1842, 1, 0.1863],
  [0.3333, 0.0556, 0.3529],
  [0.6471, 0.3333, 0.5],
  [0.6569, 1, 0.6667],
  [0.2218, 1, 0.249],
  [0.3333, 0.1981, 0.4157],
  [0.5843, 0.3333, 0.5],
  [0.6255, 1, 0.6667],
  [0.2442, 1, 0.3118],
  [0.3333, 0.3033, 0.4784],
  [0.5216, 0.3333, 0.5],
  [0.5941, 1, 0.6667],
  [0.2592, 1, 0.3745],
  [0.3333, 0.453, 0.5412],
  [0.467, 0.453, 0.5412],
  [0.5627, 1, 0.6667],
  [0.2698, 1, 0.4373],
  [0.3333, 0.6832, 0.6039],
  [0.436, 0.6832, 0.6039],
  [0.5314, 1, 0.6667],
  [0.2778, 1, 0.5],
  [0.3333, 1, 0.6667],
  [0.4167, 1, 0.6667],
  [0.5, 1, 0.6667],
  [0, 1, 0.249],
  [0.8885, 1, 0.249],
  [0.7912, 1, 0.3333],
  [0.7497, 1, 0.5],
  [0.0407, 1, 0.249],
  [0.9063, 0.6076, 0.3098],
  [0.7818, 0.6915, 0.3941],
  [0.7381, 1, 0.5608],
  [0.0827, 1, 0.249],
  [0.9427, 0.3368, 0.3725],
  [0.7664, 0.4592, 0.4569],
  [0.7222, 1, 0.6235],
  [0.1247, 1, 0.249],
  [0.0397, 0.1981, 0.4157],
  [0.7378, 0.3061, 0.5196],
  [0.7, 1, 0.6863],
  [0.1667, 1, 0.249],
  [0.1667, 0.1981, 0.4157],
  [0.6667, 0.2019, 0.5824],
  [0.6667, 1, 0.749],
  [0.2002, 1, 0.3118],
  [0.2387, 0.3033, 0.4784],
  [0.5426, 0.2019, 0.5824],
  [0.625, 1, 0.749],
  [0.2225, 1, 0.3745],
  [0.2673, 0.453, 0.5412],
  [0.4453, 0.3333, 0.6235],
  [0.5833, 1, 0.749],
  [0.2384, 1, 0.4373],
  [0.2826, 0.6832, 0.6039],
  [0.408, 0.6, 0.6863],
  [0.5417, 1, 0.749],
  [0.2503, 1, 0.5],
  [0.2922, 1, 0.6667],
  [0.3893, 1, 0.749],
  [0.5, 1, 0.749],
  [0, 1, 0.3333],
  [0.9167, 1, 0.3333],
  [0.8333, 1, 0.3333],
  [0.7778, 1, 0.5],
  [0.0304, 1, 0.3333],
  [0.9353, 0.6915, 0.3941],
  [0.8333, 0.6915, 0.3941],
  [0.7701, 1, 0.5608],
  [0.0618, 1, 0.3333],
  [0.9657, 0.4592, 0.4569],
  [0.8333, 0.4592, 0.4569],
  [0.7595, 1, 0.6235],
  [0.0931, 1, 0.3333],
  [0.0196, 0.3333, 0.5],
  [0.8333, 0.3061, 0.5196],
  [0.7448, 1, 0.6863],
  [0.1245, 1, 0.3333],
  [0.0824, 0.3333, 0.5],
  [0.8333, 0.2019, 0.5824],
  [0.7227, 1, 0.749],
  [0.1559, 1, 0.3333],
  [0.1451, 0.3333, 0.5],
  [0.8333, 0.0608, 0.6451],
  [0.6858, 1, 0.8118],
  [0.185, 1, 0.3745],
  [0.1997, 0.453, 0.5412],
  [0.3333, 0.1409, 0.7078],
  [0.6255, 1, 0.8333],
  [0.2063, 1, 0.4373],
  [0.2307, 0.6832, 0.6039],
  [0.3333, 0.453, 0.7706],
  [0.5627, 1, 0.8333],
  [0.2222, 1, 0.5],
  [0.25, 1, 0.6667],
  [0.3333, 1, 0.8333],
  [0.5, 1, 0.8333],
  [0, 1, 0.4157],
  [0.9332, 1, 0.4157],
  [0.8664, 1, 0.4157],
  [0.8052, 1, 0.5],
  [0.0244, 1, 0.4157],
  [0.9503, 0.7449, 0.4765],
  [0.872, 0.7449, 0.4765],
  [0.8013, 1, 0.5608],
  [0.0495, 1, 0.4157],
  [0.9754, 0.634, 0.5392],
  [0.8803, 0.634, 0.5392],
  [0.796, 1, 0.6235],
  [0.0747, 1, 0.4157],
  [0.0131, 0.5962, 0.5824],
  [0.8932, 0.5764, 0.602],
  [0.7885, 1, 0.6863],
  [0.0998, 1, 0.4157],
  [0.0551, 0.5962, 0.5824],
  [0.9157, 0.4971, 0.6647],
  [0.7773, 1, 0.749],
  [0.125, 1, 0.4157],
  [0.0971, 0.5962, 0.5824],
  [0.9654, 0.3813, 0.7275],
  [0.7587, 1, 0.8118],
  [0.1502, 1, 0.4157],
  [0.1391, 0.5962, 0.5824],
  [0.0833, 0.3281, 0.749],
  [0.7214, 1, 0.8745],
  [0.1749, 1, 0.4373],
  [0.18, 0.6832, 0.6039],
  [0.2013, 0.453, 0.7706],
  [0.624, 1, 0.9157],
  [0.1948, 1, 0.5],
  [0.2088, 1, 0.6667],
  [0.251, 1, 0.8333],
  [0.5, 1, 0.9157],
  [0.9444, 1, 0.5],
  [0.8889, 1, 0.5],
  [0.0203, 1, 0.5],
  [0.9598, 1, 0.5608],
  [0.8966, 1, 0.5608],
  [0.8333, 1, 0.5608],
  [0.0412, 1, 0.5],
  [0.9809, 1, 0.6235],
  [0.9071, 1, 0.6235],
  [0.8333, 1, 0.6235],
  [0.0621, 1, 0.5],
  [0.0098, 1, 0.6667],
  [0.9219, 1, 0.6863],
  [0.8333, 1, 0.6863],
  [0.083, 1, 0.5],
  [0.0412, 1, 0.6667],
  [0.944, 1, 0.749],
  [0.8333, 1, 0.749],
  [0.1039, 1, 0.5],
  [0.0725, 1, 0.6667],
  [0.9809, 1, 0.8118],
  [0.8333, 1, 0.8118],
  [0.1248, 1, 0.5],
  [0.1039, 1, 0.6667],
  [0.0412, 1, 0.8333],
  [0.8333, 1, 0.8745],
  [0.1458, 1, 0.5],
  [0.1353, 1, 0.6667],
  [0.1039, 1, 0.8333],
  [0.8333, 1, 0.9373],
  [0.1667, 1, 0.6667],
  [0.1667, 1, 0.8333],
  [0.6667, 1, 0.9],
  [0.8333, 1, 0.9],
  [0.5, 1, 0.6],
  [0.5, 1, 0.7],
  [0.5, 1, 0.8],
  [0.5, 1, 0.9],
  [0.3333, 1, 0.249],
  [0.4449, 1, 0.249],
  [0.5422, 1, 0.3333],
  [0.5837, 1, 0.5],
  [0.3333, 1, 0.3118],
  [0.4224, 1, 0.3118],
  [0.5108, 1, 0.3333],
  [0.5627, 1, 0.5],
  [0.3333, 1, 0.3745],
  [0.4075, 1, 0.3745],
  [0.4817, 1, 0.3745],
  [0.5418, 1, 0.5],
  [0.3333, 1, 0.4373],
  [0.3969, 1, 0.4373],
  [0.4604, 1, 0.4373],
  [0.5209, 1, 0.5],
  [0.3889, 1, 0.5],
  [0.4444, 1, 0.5],
  [0, 1, 0.0824],
  [0.749, 1, 0.1667],
  [0.7078, 1, 0.3333],
  [0.6941, 1, 0.5],
  [0.123, 1, 0.0824],
  [0.7006, 0.4655, 0.2275],
  [0.6799, 0.6915, 0.3941],
  [0.6749, 1, 0.5608],
  [0.2222, 1, 0.1235],
  [0.5853, 0.3386, 0.249],
  [0.1222, 1, 0.9706],
  [0.6667, 0.0215, 0.6353],
  [0, 0, 0.502],
  [0, 1, 0.5],
  [0.3333, 1, 0.5],
  [0.1667, 1, 0.5],
  [0.6667, 1, 0.5],
  [0.8333, 1, 0.5],
  [0.5, 1, 0.5],
  [0, 0, 1]
]

const BIAS_256 = 0
const lightnessSteps = 4
const saturationSteps = 4

/* eslint-disable prettier/prettier */
const ditherTable = new Uint8Array([
  0, 48, 12, 60, 3, 51, 15, 63,
  32, 16, 44, 28, 35, 19, 47, 31,
  8, 56, 4, 52, 11, 59, 7, 55,
  40, 24, 36, 20, 43, 27, 39, 23,
  2, 50, 14, 62, 1, 49, 13, 61,
  34, 18, 46, 30, 33, 17, 45, 29,
  10, 58, 6, 54, 9, 57, 5, 53,
  42, 26, 38, 22, 41, 25, 37, 21
])
/* eslint-enable prettier/prettier */

function hueDistance(h1: number, h2: number): number {
  const diff = Math.abs(h1 - h2)

  return diff < 0.5 ? diff : 1 - diff
}

const lightnessStep = (l: number) => Math.round(l * lightnessSteps) / lightnessSteps
const saturationStep = (s: number) => Math.round(s * saturationSteps) / saturationSteps

const closestColorsCache = new Map<number, [Vec3, Vec3]>()

function closestColors(hue: number): [Vec3, Vec3] {
  const cachedResult = closestColorsCache.get(hue)
  if (cachedResult) return cachedResult

  let closest: Vec3 = [-2, 0, 0]
  let secondClosest: Vec3 = [-2, 0, 0]
  let minDist = Infinity
  let secondMinDist = Infinity

  for (const color of PALETTE_256) {
    const dist = hueDistance(color[0], hue)
    if (dist < minDist) {
      secondClosest = closest
      secondMinDist = minDist
      closest = color
      minDist = dist
    } else if (dist < secondMinDist) {
      secondClosest = color
      secondMinDist = dist
    }
  }

  const result: [Vec3, Vec3] = [closest, secondClosest]
  closestColorsCache.set(hue, result)

  return result
}

function dither(pos: [number, number], color: Vec3): Vec3 {
  const index = (pos[0] & 7) + ((pos[1] & 7) << 3)
  const limit = (ditherTable[index] + 1) / 64 + BIAS_256

  const [closest, secondClosest] = closestColors(color[0])
  const hueDiff = hueDistance(color[0], closest[0]) / hueDistance(secondClosest[0], closest[0])

  const l1 = lightnessStep(Math.max(color[2] - 0.125, 0))
  const l2 = lightnessStep(Math.min(color[2] + 0.124, 1))
  const lightnessDiff = (color[2] - l1) / (l2 - l1)

  const resultColor: Vec3 = hueDiff < limit ? [...closest] : [...secondClosest]
  resultColor[2] = lightnessDiff < limit ? l1 : l2

  const s1 = saturationStep(Math.max(color[1] - 0.125, 0))
  const s2 = saturationStep(Math.min(color[1] + 0.124, 1))
  const saturationDiff = (color[1] - s1) / (s2 - s1)

  resultColor[1] = saturationDiff < limit ? s1 : s2

  return hslToRgb(resultColor)
}

export function orderedBayer(source: Buffer, width: number, height: number): Buffer {
  return render(
    source,
    width,
    height,
    (pixelCoords, texture) => {
      const color = texture(pixelCoords)
      const ditheredColor = dither(pixelCoords, rgbToHsl(color))

      return [...ditheredColor, color[3]]
    },
    { textureFilter: TEXTURE_FILTER.NEAREST }
  )
}