var EARTHRADIUS = 6370996.81;
var MCBAND = [12890594.86, 8362377.87, 5591021, 3481989.83, 1678043.12, 0];
var LLBAND = [75, 60, 45, 30, 15, 0];
var MC2LL = [[1.410526172116255e-8, 0.00000898305509648872, -1.9939833816331, 200.9824383106796, -187.2403703815547, 91.6087516669843, -23.38765649603339, 2.57121317296198, -0.03801003308653, 17337981.2], [-7.435856389565537e-9, 0.000008983055097726239, -0.78625201886289, 96.32687599759846, -1.85204757529826, -59.36935905485877, 47.40033549296737, -16.50741931063887, 2.28786674699375, 10260144.86], [-3.030883460898826e-8, 0.00000898305509983578, 0.30071316287616, 59.74293618442277, 7.357984074871, -25.38371002664745, 13.45380521110908, -3.29883767235584, 0.32710905363475, 6856817.37], [-1.981981304930552e-8, 0.000008983055099779535, 0.03278182852591, 40.31678527705744, 0.65659298677277, -4.44255534477492, 0.85341911805263, 0.12923347998204, -0.04625736007561, 4482777.06], [3.09191371068437e-9, 0.000008983055096812155, 0.00006995724062, 23.10934304144901, -0.00023663490511, -0.6321817810242, -0.00663494467273, 0.03430082397953, -0.00466043876332, 2555164.4], [2.890871144776878e-9, 0.000008983055095805407, -3.068298e-8, 7.47137025468032, -0.00000353937994, -0.02145144861037, -0.00001234426596, 0.00010322952773, -0.00000323890364, 826088.5]];
var LL2MC = [[-0.0015702102444, 111320.7020616939, 1704480524535203, -10338987376042340, 26112667856603880, -35149669176653700, 26595700718403920, -10725012454188240, 1800819912950474, 82.5], [0.0008277824516172526, 111320.7020463578, 647795574.6671607, -4082003173.641316, 10774905663.51142, -15171875531.51559, 12053065338.62167, -5124939663.577472, 913311935.9512032, 67.5], [0.00337398766765, 111320.7020202162, 4481351.045890365, -23393751.19931662, 79682215.47186455, -115964993.2797253, 97236711.15602145, -43661946.33752821, 8477230.501135234, 52.5], [0.00220636496208, 111320.7020209128, 51751.86112841131, 3796837.749470245, 992013.7397791013, -1221952.21711287, 1340652.697009075, -620943.6990984312, 144416.9293806241, 37.5], [-0.0003441963504368392, 111320.7020576856, 278.2353980772752, 2485758.690035394, 6070.750963243378, 54821.18345352118, 9540.606633304236, -2710.55326746645, 1405.483844121726, 22.5], [-0.0003218135878613132, 111320.7020701615, 0.00369383431289, 823725.6402795718, 0.46104986909093, 2351.343141331292, 1.58060784298199, 8.77738589078284, 0.37238884252424, 7.45]];
/**
 * 百度墨卡托坐标  转  百度经纬度坐标
 * @param x
 * @param y
 * @return
 */
export function convertMC2LL (lng, lat) {
  var cF = null;
  lng = Math.abs(lng);
  lat = Math.abs(lat);

  for (var cE = 0; cE < MCBAND.length; cE++) {
    if (lat >= MCBAND[cE]) {
      cF = MC2LL[cE];
      break;
    }
  }
  return converter(lng, lat, cF);
}

/**
 * 百度经纬度坐标 转  转百度墨卡托坐标
 * @param lng
 * @param lat
 * @return
 */

function convertor (cC, cD) {
  if (!cC || !cD) {
    return null;
  }
  let T = cD[0] + cD[1] * Math.abs(cC.x);
  const cB = Math.abs(cC.y) / cD[9];
  let cE = cD[2] + cD[3] * cB + cD[4] * cB * cB +
    cD[5] * cB * cB * cB + cD[6] * cB * cB * cB * cB +
    cD[7] * cB * cB * cB * cB * cB +
    cD[8] * cB * cB * cB * cB * cB * cB;
  T *= (cC.x < 0 ? -1 : 1);
  cE *= (cC.y < 0 ? -1 : 1);
  return [T, cE];
}
export function convertLL2MC (lon, lat) {
  let cD, cC, len;
  let T = [];
  T.x = lon
  T.y = lat
  T.x = getLoop(T.x, -180, 180);
  T.y = getRange(T.y, -74, 74);
  const cB = T;
  for (cC = 0, len = LLBAND.length; cC < len; cC++) {
    if (cB.y >= LLBAND[cC]) {
      cD = LL2MC[cC];
      break;
    }
  }
  if (!cD) {
    for (cC = LLBAND.length - 1; cC >= 0; cC--) {
      if (cB.y <= -LLBAND[cC]) {
        cD = LL2MC[cC];
        break;
      }
    }
  }
  const cE = convertor(T, cD);
  return cE;
}


export function converter (lng, lat, cE) {
  var lngTemp = cE[0] + cE[1] * Math.abs(lng);
  var cC = Math.abs(lat) / cE[9];
  var latTemp = cE[2] + cE[3] * cC + cE[4] * cC * cC + cE[5] * cC * cC * cC + cE[6] * cC * cC * cC * cC + cE[7] * cC * cC * cC * cC * cC + cE[8] * cC * cC * cC * cC * cC * cC;
  lngTemp *= (lng < 0 ? -1 : 1);
  latTemp *= (lat < 0 ? -1 : 1);
  return [latTemp, lngTemp];
}

function getLoop (lng, min, max) {
  while (lng > max) {
    lng -= max - min;
  }
  while (lng < min) {
    lng += max - min;
  }
  return lng;
}

function getRange (lat, min, max) {
  if (min != null) {
    lat = Math.max(lat, min);
  }
  if (max != null) {
    lat = Math.min(lat, max);
  }
  return lat;
}