"use strict";Object.defineProperty(exports, "__esModule", {value: true});var __defProp = Object.defineProperty;
var __defProps = Object.defineProperties;
var __getOwnPropDescs = Object.getOwnPropertyDescriptors;
var __getOwnPropSymbols = Object.getOwnPropertySymbols;
var __hasOwnProp = Object.prototype.hasOwnProperty;
var __propIsEnum = Object.prototype.propertyIsEnumerable;
var __defNormalProp = (obj, key, value) => key in obj ? __defProp(obj, key, { enumerable: true, configurable: true, writable: true, value }) : obj[key] = value;
var __spreadValues = (a, b) => {
  for (var prop in b || (b = {}))
    if (__hasOwnProp.call(b, prop))
      __defNormalProp(a, prop, b[prop]);
  if (__getOwnPropSymbols)
    for (var prop of __getOwnPropSymbols(b)) {
      if (__propIsEnum.call(b, prop))
        __defNormalProp(a, prop, b[prop]);
    }
  return a;
};
var __spreadProps = (a, b) => __defProps(a, __getOwnPropDescs(b));

// index.ts
var _distance = require('@turf/distance');
var _meta = require('@turf/meta');




var _helpers = require('@turf/helpers');
var _invariant = require('@turf/invariant');
function nearestPointOnLine(lines, pt, options = {}) {
  if (!lines || !pt) {
    throw new Error("lines and pt are required arguments");
  }
  const ptPos = _invariant.getCoord.call(void 0, pt);
  let closestPt = _helpers.point.call(void 0, [Infinity, Infinity], {
    dist: Infinity,
    index: -1,
    multiFeatureIndex: -1,
    location: -1
  });
  let length = 0;
  _meta.flattenEach.call(void 0, 
    lines,
    function(line, _featureIndex, multiFeatureIndex) {
      const coords = _invariant.getCoords.call(void 0, line);
      for (let i = 0; i < coords.length - 1; i++) {
        const start = _helpers.point.call(void 0, coords[i]);
        const startPos = _invariant.getCoord.call(void 0, start);
        const stop = _helpers.point.call(void 0, coords[i + 1]);
        const stopPos = _invariant.getCoord.call(void 0, stop);
        const sectionLength = _distance.distance.call(void 0, start, stop, options);
        let intersectPos;
        let wasEnd;
        if (stopPos[0] === ptPos[0] && stopPos[1] === ptPos[1]) {
          [intersectPos, wasEnd] = [stopPos, true];
        } else if (startPos[0] === ptPos[0] && startPos[1] === ptPos[1]) {
          [intersectPos, wasEnd] = [startPos, false];
        } else {
          [intersectPos, wasEnd] = nearestPointOnSegment(
            startPos,
            stopPos,
            ptPos
          );
        }
        const intersectPt = _helpers.point.call(void 0, intersectPos, {
          dist: _distance.distance.call(void 0, pt, intersectPos, options),
          multiFeatureIndex,
          location: length + _distance.distance.call(void 0, start, intersectPos, options)
        });
        if (intersectPt.properties.dist < closestPt.properties.dist) {
          closestPt = __spreadProps(__spreadValues({}, intersectPt), {
            properties: __spreadProps(__spreadValues({}, intersectPt.properties), {
              // Legacy behaviour where index progresses to next segment # if we
              // went with the end point this iteration.
              index: wasEnd ? i + 1 : i
            })
          });
        }
        length += sectionLength;
      }
    }
  );
  return closestPt;
}
function dot(v1, v2) {
  const [v1x, v1y, v1z] = v1;
  const [v2x, v2y, v2z] = v2;
  return v1x * v2x + v1y * v2y + v1z * v2z;
}
function cross(v1, v2) {
  const [v1x, v1y, v1z] = v1;
  const [v2x, v2y, v2z] = v2;
  return [v1y * v2z - v1z * v2y, v1z * v2x - v1x * v2z, v1x * v2y - v1y * v2x];
}
function magnitude(v) {
  return Math.sqrt(Math.pow(v[0], 2) + Math.pow(v[1], 2) + Math.pow(v[2], 2));
}
function normalize(v) {
  const mag = magnitude(v);
  return [v[0] / mag, v[1] / mag, v[2] / mag];
}
function lngLatToVector(a) {
  const lat = _helpers.degreesToRadians.call(void 0, a[1]);
  const lng = _helpers.degreesToRadians.call(void 0, a[0]);
  return [
    Math.cos(lat) * Math.cos(lng),
    Math.cos(lat) * Math.sin(lng),
    Math.sin(lat)
  ];
}
function vectorToLngLat(v) {
  const [x, y, z] = v;
  const zClamp = Math.min(Math.max(z, -1), 1);
  const lat = _helpers.radiansToDegrees.call(void 0, Math.asin(zClamp));
  const lng = _helpers.radiansToDegrees.call(void 0, Math.atan2(y, x));
  return [lng, lat];
}
function nearestPointOnSegment(posA, posB, posC) {
  const A = lngLatToVector(posA);
  const B = lngLatToVector(posB);
  const C = lngLatToVector(posC);
  const segmentAxis = cross(A, B);
  if (segmentAxis[0] === 0 && segmentAxis[1] === 0 && segmentAxis[2] === 0) {
    if (dot(A, B) > 0) {
      return [[...posB], true];
    } else {
      return [[...posC], false];
    }
  }
  const targetAxis = cross(segmentAxis, C);
  if (targetAxis[0] === 0 && targetAxis[1] === 0 && targetAxis[2] === 0) {
    return [[...posB], true];
  }
  const intersectionAxis = cross(targetAxis, segmentAxis);
  const I1 = normalize(intersectionAxis);
  const I2 = [-I1[0], -I1[1], -I1[2]];
  const I = dot(C, I1) > dot(C, I2) ? I1 : I2;
  const segmentAxisNorm = normalize(segmentAxis);
  const cmpAI = dot(cross(A, I), segmentAxisNorm);
  const cmpIB = dot(cross(I, B), segmentAxisNorm);
  if (cmpAI >= 0 && cmpIB >= 0) {
    return [vectorToLngLat(I), false];
  }
  if (dot(A, C) > dot(B, C)) {
    return [[...posA], false];
  } else {
    return [[...posB], true];
  }
}
var index_default = nearestPointOnLine;



exports.default = index_default; exports.nearestPointOnLine = nearestPointOnLine;
//# sourceMappingURL=index.cjs.map