import { Quat, quat } from './Quat';
import { Mat3 } from './Mat3';
import { Mat4 } from './Mat4';
import { clamp, delta4 } from './Math';
import { Euler } from './Euler';
import { DistanceResult } from '../alg/result';
import { Line, line } from '../struct/3d/Line';
import { Ray } from '../struct/3d/Ray';
import { Segment } from '../struct/3d/Segment';
import { Plane } from '../struct/3d/Plane';
import { EventHandler } from '../render/eventhandler';
import { Triangle } from '../struct/3d/Triangle';
import { Capsule } from '../struct/3d/Capsule';
import { Rectangle } from '../struct/3d/Rectangle';
import { Circle } from '../struct/3d/Circle';
import { Disk } from '../struct/3d/Disk';
import { Polyline } from '..';
// import { wgs84RadiiSquared } from '../gis/gis';
export interface IVec2 {
  x: number;
  y: number;
}
export interface IVec3 extends IVec2 {
  z: number;
}
export interface IVec4 extends IVec3 {
  w: number;
}

export class Vec3 extends EventHandler implements IVec3 {

  constructor(private _x: number = 0, private _y: number = 0, private _z: number = 0) {
    super();
  }
  get x() {
    return this._x;
  }

  set x(value) {
    if (this._x !== value) {
      this._x = value;
      this.fire('change', 'x', this._x, value)
    }
  }

  get y() {
    return this._y;
  }

  set y(value) {
    if (this._y !== value) {
      this._y = value;
      this.fire('change', 'y', this._y, value)
    }
  }

  get z() {
    return this._z;
  }

  set z(value) {
    if (this._z !== value) {
      this._z = value;
      this.fire('change', 'z', this._z, value)
    }
  }



  static isVec3(v: any) {
    return !isNaN(v.x) && !isNaN(v.y) && !isNaN(v.z) && isNaN(v.w);
  }


  get isVec3() { return true; }

  static get Up() {
    return new Vec3(0, 1, 0);
  }

  static get Down() {
    return new Vec3(0, 1, 0);
  }

  static get UnitX() {
    return new Vec3(1, 0, 0);
  }
  static get UnitY() {
    return new Vec3(0, 1, 0);
  }
  static get UnitZ() {
    return new Vec3(0, 0, 1);
  }


  set(x: number, y: number, z: number) {
    this._x = x;
    this._y = y;
    this._z = z;
    this.fire('change');
    return this;
  }

  setScalar(scalar: number) {
    this._x = scalar;
    this._y = scalar;
    this._z = scalar;

    this.fire('change');
    return this;
  }

  setComponent(index: number, value: number) {
    switch (index) {
      case 0:
        this._x = value;
        break;
      case 1:
        this._y = value;
        break;
      case 2:
        this._z = value;
        break;
      default:
        throw new Error("index is out of range: " + index);
    }

    return this;
  }

  getComponent(index: number) {
    switch (index) {
      case 0:
        return this._x;
      case 1:
        return this._y;
      case 2:
        return this._z;
      default:
        throw new Error("index is out of range: " + index);
    }
  }

  clone(): Vec3 {
    return new Vec3(this._x, this._y, this._z);
  }

  copy(v: Vec3) {
    this._x = v.x;
    this._y = v.y;
    this._z = v.z;

    this.fire('change');
    return this;
  }

  add(v: Vec3, w?: Vec3) {
    if (w !== undefined) {
      console.warn(
        "Vec3: .add() now only accepts one argument. Use .addVecs( a, b ) instead."
      );
      return this.addVecs(v, w);
    }

    this._x += v.x;
    this._y += v.y;
    this._z += v.z;

    this.fire('change');
    return this;
  }

  addScalar(s: number) {
    this._x += s;
    this._y += s;
    this._z += s;

    this.fire('change');
    return this;
  }

  addVecs(a: Vec3, b: Vec3) {
    this._x = a.x + b.x;
    this._y = a.y + b.y;
    this._z = a.z + b.z;

    this.fire('change');
    return this;
  }

  addScaledVec(v: Vec3, s: number) {
    this._x += v.x * s;
    this._y += v.y * s;
    this._z += v.z * s;

    this.fire('change');
    return this;
  }

  sub(v: Vec3, w?: Vec3) {
    if (w !== undefined) {
      console.warn(
        "Vec3: .sub() now only accepts one argument. Use .subVecs( a, b ) instead."
      );
      return this.subVecs(v, w);
    }

    this._x -= v.x;
    this._y -= v.y;
    this._z -= v.z;

    this.fire('change');
    return this;
  }

  subScalar(s: number) {
    this._x -= s;
    this._y -= s;
    this._z -= s;

    this.fire('change');
    return this;
  }

  subVecs(a: Vec3, b: Vec3) {
    this._x = a.x - b.x;
    this._y = a.y - b.y;
    this._z = a.z - b.z;

    this.fire('change');
    return this;
  }

  multiply(v: Vec3, w?: Vec3) {
    if (w !== undefined) {
      return this.multiplyVecs(v, w);
    }

    this._x *= v.x;
    this._y *= v.y;
    this._z *= v.z;

    this.fire('change');
    return this;
  }

  multiplyScalar(scalar: number) {
    this._x *= scalar;
    this._y *= scalar;
    this._z *= scalar;

    this.fire('change');
    return this;
  }

  multiplyVecs(a: Vec3, b: Vec3) {
    this._x = a.x * b.x;
    this._y = a.y * b.y;
    this._z = a.z * b.z;

    this.fire('change');
    return this;
  }

  applyEuler(euler: Euler) {
    if (!(euler && euler.isEuler)) {
      console.error(
        "Vec3: .applyEuler() now expects an Euler rotation rather than a Vec3 and order."
      );
    }

    return this.applyQuat(_quat.setFromEuler(euler));
  }

  applyAxisAngle(axis: any, angle: any) {
    return this.applyQuat(_quat.setFromAxisAngle(axis, angle));
  }

  applyNormalMat(m: Mat3) {
    return this.applyMat3(m).normalize();
  }

  applyMat3(m: Mat3) {
    var x = this._x,
      y = this._y,
      z = this._z;
    var e = m.elements;

    this._x = e[0] * x + e[3] * y + e[6] * z;
    this._y = e[1] * x + e[4] * y + e[7] * z;
    this._z = e[2] * x + e[5] * y + e[8] * z;

    this.fire('change');
    return this;
  }

  applyMat4(m: Mat4) {
    var x = this._x,
      y = this._y,
      z = this._z;
    var e = m.elements;

    var w = 1 / (e[3] * x + e[7] * y + e[11] * z + e[15]);

    this._x = (e[0] * x + e[4] * y + e[8] * z + e[12]) * w;
    this._y = (e[1] * x + e[5] * y + e[9] * z + e[13]) * w;
    this._z = (e[2] * x + e[6] * y + e[10] * z + e[14]) * w;

    this.fire('change');
    return this;
  }

  applyQuat(q: { x: any; y: any; z: any; w: any; }) {
    var x = this._x,
      y = this._y,
      z = this._z;
    var qx = q.x,
      qy = q.y,
      qz = q.z,
      qw = q.w;

    // calculate Quat * Vec

    var ix = qw * x + qy * z - qz * y;
    var iy = qw * y + qz * x - qx * z;
    var iz = qw * z + qx * y - qy * x;
    var iw = -qx * x - qy * y - qz * z;

    // calculate result * inverse Quat

    this._x = ix * qw + iw * -qx + iy * -qz - iz * -qy;
    this._y = iy * qw + iw * -qy + iz * -qx - ix * -qz;
    this._z = iz * qw + iw * -qz + ix * -qy - iy * -qx;

    this.fire('change');
    return this;
  }

  project(camera: { matrixWorldInverse: any; projectionMat: any; }) {
    return this.applyMat4(camera.matrixWorldInverse).applyMat4(
      camera.projectionMat
    );
  }

  unproject(camera: { projectionMatInverse: any; matrixWorld: any; }) {
    return this.applyMat4(camera.projectionMatInverse).applyMat4(
      camera.matrixWorld
    );
  }

  transformDirection(m: Mat4) {
    // input: Mat4 affine matrix
    // Vec interpreted as a direction

    var x = this._x,
      y = this._y,
      z = this._z;
    var e = m.elements;

    this._x = e[0] * x + e[4] * y + e[8] * z;
    this._y = e[1] * x + e[5] * y + e[9] * z;
    this._z = e[2] * x + e[6] * y + e[10] * z;

    this.fire('change');
    return this.normalize();
  }

  divide(v: Vec3) {
    this._x /= v.x;
    this._y /= v.y;
    this._z /= v.z;

    this.fire('change');
    return this;
  }

  divideScalar(scalar: number) {
    return this.multiplyScalar(1 / scalar);
  }

  min(v: Vec3) {
    this._x = Math.min(this._x, v.x);
    this._y = Math.min(this._y, v.y);
    this._z = Math.min(this._z, v.z);

    this.fire('change');
    return this;
  }

  max(v: Vec3) {
    this._x = Math.max(this._x, v.x);
    this._y = Math.max(this._y, v.y);
    this._z = Math.max(this._z, v.z);

    this.fire('change');
    return this;
  }

  clamp(min: Vec3, max: Vec3) {
    // assumes min < max, componentwise

    this._x = Math.max(min.x, Math.min(max.x, this._x));
    this._y = Math.max(min.y, Math.min(max.y, this._y));
    this._z = Math.max(min.z, Math.min(max.z, this._z));

    this.fire('change');
    return this;
  }

  clampScalar(minVal: number, maxVal: number) {
    this._x = Math.max(minVal, Math.min(maxVal, this._x));
    this._y = Math.max(minVal, Math.min(maxVal, this._y));
    this._z = Math.max(minVal, Math.min(maxVal, this._z));

    this.fire('change');
    return this;
  }

  clampLength(min: number, max: number) {
    var length = this.length();

    return this.divideScalar(length || 1).multiplyScalar(
      Math.max(min, Math.min(max, length))
    );
  }

  floor() {
    this._x = Math.floor(this._x);
    this._y = Math.floor(this._y);
    this._z = Math.floor(this._z);

    this.fire('change');
    return this;
  }

  ceil() {
    this._x = Math.ceil(this._x);
    this._y = Math.ceil(this._y);
    this._z = Math.ceil(this._z);

    this.fire('change');
    return this;
  }

  round() {
    this._x = Math.round(this._x);
    this._y = Math.round(this._y);
    this._z = Math.round(this._z);

    this.fire('change');
    return this;
  }

  roundToZero() {
    this._x = this._x < 0 ? Math.ceil(this._x) : Math.floor(this._x);
    this._y = this._y < 0 ? Math.ceil(this._y) : Math.floor(this._y);
    this._z = this._z < 0 ? Math.ceil(this._z) : Math.floor(this._z);

    this.fire('change');
    return this;
  }

  negate() {
    this._x = -this._x;
    this._y = -this._y;
    this._z = -this._z;

    this.fire('change');
    return this;
  }

  dot(v: Vec3) {
    return this._x * v.x + this._y * v.y + this._z * v.z;
  }

  // TODO lengthSquared?

  lengthSq() {
    return this._x * this._x + this._y * this._y + this._z * this._z;
  }

  length() {
    return Math.sqrt(this._x * this._x + this._y * this._y + this._z * this._z);
  }

  manhattanLength() {
    return Math.abs(this._x) + Math.abs(this._y) + Math.abs(this._z);
  }

  normalize(robust = false) {
    return this.divideScalar(this.length() || 1);

    // if (robust)
    // {
    //   var maxAbsComp = Math.abs(v[0]);
    //   for (var i = 1; i < N; ++i)
    //   {
    //     var absComp = Math.abs(v[i]);
    //     if (absComp > maxAbsComp)
    //     {
    //       maxAbsComp = absComp;
    //     }
    //   }

    //   var length;
    //   if (maxAbsComp > 0)
    //   {
    //     v /= maxAbsComp;
    //     length = Math.sqrt(Dot(v, v));
    //     v /= length;
    //     length *= maxAbsComp;
    //   }
    //   else
    //   {
    //     length = 0;
    //     for (var i = 0; i < N; ++i)
    //     {
    //       v[i] = 0;
    //     }
    //   }
    //   return length;
    // }
    // else
    // {
    //   var length = this.length();
    //   if (length > 0)
    //   {
    //     v /= length;
    //   }
    //   else
    //   {
    //     for (var i = 0; i < N; ++i)
    //     {
    //       v[i] = 0;
    //     }
    //   }
    // }
  }

  setLength(length: any) {
    return this.normalize().multiplyScalar(length);
  }

  lerp(v: Vec3, alpha: number) {
    this._x += (v.x - this._x) * alpha;
    this._y += (v.y - this._y) * alpha;
    this._z += (v.z - this._z) * alpha;

    return this;
  }

  lerpVecs(v1: Vec3, v2: any, alpha: any) {
    return this.subVecs(v2, v1)
      .multiplyScalar(alpha)
      .add(v1);
  }

  cross(v: Vec3, w?: Vec3) {
    if (w !== undefined) {
      console.warn(
        "Vec3: .cross() now only accepts one argument. Use .crossVecs( a, b ) instead."
      );
      return this.crossVecs(v, w);
    }

    return this.crossVecs(this, v);
  }

  crossVecs(a: Vec3, b: Vec3) {
    var ax = a.x,
      ay = a.y,
      az = a.z;
    var bx = b.x,
      by = b.y,
      bz = b.z;

    this._x = ay * bz - az * by;
    this._y = az * bx - ax * bz;
    this._z = ax * by - ay * bx;

    return this;
  }

  projectOnVec(vec: Vec3) {
    var scalar = vec.dot(this) / vec.lengthSq();

    return this.copy(vec).multiplyScalar(scalar);
  }

  /**
   * 投影到法线的所在平面  相当于平面上距离点最近的点
   * @param planeNormal 
   * @returns 
   */
  projectOnPlaneNormal(planeNormal: any) {
    _vec.copy(this).projectOnVec(planeNormal);

    return this.sub(_vec);
  }

  /**
   * 投影到平面
   * @param normal 正交化的法线
   * @param w  距离
   * @returns 
   */
  projectOnPlaneNormalDis(normal: Vec3, w: number) {
    var scalar = normal.dot(this) - w;

    _vec.copy(normal).multiplyScalar(scalar);

    return this.sub(_vec);
  }

  /**
 * 投影到平面
 * @param plane 平面 
 * @returns 
 */
  projectOnPlane(plane: Plane) {
    var scalar = plane.normal.dot(this) - plane.w;

    _vec.copy(plane.normal).multiplyScalar(scalar);

    return this.sub(_vec);
  }


  /**
   * 从指定方向线(斜线，也可能是法线)上投影到平面
   * @param planeNormal 
   * @param dir 
   */
  projectDirectionOnPlane(plane: Plane, dir: Vec3) {
    var scalar = plane.normal.dot(this) - plane.w;

    _vec.copy(plane.normal).multiplyScalar(scalar);

    _vec.negate().add(this);
    var len = this.distanceTo(_vec);

    var nlen = len / plane.normal.dot(dir)

    this.add(_vec.copy(dir).negate().multiplyScalar(nlen));

    return this;
  }

  reflect(normal: any) {
    // reflect incident Vec off plane orthogonal to normal
    // normal is assumed to have unit length

    return this.sub(_vec.copy(normal).multiplyScalar(2 * this.dot(normal)));
  }

  angleTo(v: Vec3, normal?: Vec3 | any) {
    if (normal)
      return this.angleToEx(v, normal)

    var theta = this.dot(v) / Math.sqrt(this.lengthSq() * v.lengthSq());
    return Math.acos(clamp(theta, -1, 1));
  }

  angleToEx(v: Vec3, normal: Vec3) {
    var theta = this.dot(v) / Math.sqrt(this.lengthSq() * v.lengthSq());

    if (this.clone().cross(v).dot(normal) > 0)
      return Math.acos(clamp(theta, -1, 1));
    else
      return Math.PI * 2 - Math.acos(clamp(theta, -1, 1));
  }

  distanceTo(v: any) {
    return Math.sqrt(this.distanceToSquared(v));
  }

  distanceToSquared(v: Vec3) {
    var dx = this._x - v.x,
      dy = this._y - v.y,
      dz = this._z - v.z;

    return dx * dx + dy * dy + dz * dz;
  }

  manhattanDistanceTo(v: Vec3) {
    return (
      Math.abs(this._x - v.x) + Math.abs(this._y - v.y) + Math.abs(this._z - v.z)
    );
  }

  setFromSpherical(s: { radius: number; phi: number; theta: number; }) {
    return this.setFromSphericalCoords(s.radius, s.phi, s.theta);
  }

  setFromSphericalCoords(radius: number, phi: number, theta: number) {
    var sinPhiRadius = Math.sin(phi) * radius;

    this._x = sinPhiRadius * Math.sin(theta);
    this._y = Math.cos(phi) * radius;
    this._z = sinPhiRadius * Math.cos(theta);

    return this;
  }

  setFromCylindrical(c: { radius: any; theta: any; y: any; }) {
    return this.setFromCylindricalCoords(c.radius, c.theta, c.y);
  }

  setFromCylindricalCoords(radius: number, theta: number, y: number) {
    this._x = radius * Math.sin(theta);
    this._y = y;
    this._z = radius * Math.cos(theta);

    return this;
  }

  setFromMatPosition(m: { elements: any; }) {
    var e = m.elements;

    this._x = e[12];
    this._y = e[13];
    this._z = e[14];

    return this;
  }

  setFromMatScale(m: any) {
    var sx = this.setFromMatColumn(m, 0).length();
    var sy = this.setFromMatColumn(m, 1).length();
    var sz = this.setFromMatColumn(m, 2).length();

    this._x = sx;
    this._y = sy;
    this._z = sz;

    return this;
  }

  setFromMatColumn(m: { elements: any; }, index: number) {
    return this.fromArray(m.elements, index * 4);
  }

  equals(v: Vec3) {
    return v.x === this._x && v.y === this._y && v.z === this._z;
  }

  fromArray(array: ArrayLike<number>, offset?: number) {
    if (offset === undefined) offset = 0;

    this._x = array[offset];
    this._y = array[offset + 1];
    this._z = array[offset + 2];

    return this;
  }

  toArray(array: number[] = [], offset: number = 0) {

    array[offset] = this._x;
    array[offset + 1] = this._y;
    array[offset + 2] = this._z;

    return array;
  }

  fromBufferAttribute(attribute: { getX: (arg0: any) => number; getY: (arg0: any) => number; getZ: (arg0: any) => number; }, index: any, offset?: number) {
    if (offset !== undefined) {
      console.warn(
        "Vec3: offset has been removed from .fromBufferAttribute()."
      );
    }

    this._x = attribute.getX(index);
    this._y = attribute.getY(index);
    this._z = attribute.getZ(index);

    return this;
  }

  toFixed(fractionDigits: number | undefined) {
    if (fractionDigits !== undefined) {
      this._x = parseFloat(this._x.toFixed(fractionDigits))
      this._y = parseFloat(this._y.toFixed(fractionDigits))
      this._z = parseFloat(this._z.toFixed(fractionDigits))
    }
    return this;
  }

  //---Distance-------------------------------------------------------------------------------
  distancePoint(point: Vec3): DistanceResult {
    const result: DistanceResult = {};
    result.distanceSqr = this.distanceToSquared(point);
    result.distance = Math.sqrt(result.distanceSqr);
    return result;
  }

  distanceVec3(point: Vec3): DistanceResult {
    return this.distancePoint(point);
  }


  /**
   * 点到直线的距离  point distance to Line
   * @param line 
   */
  distanceLine(line: Line): DistanceResult {
    const result: DistanceResult = { parameters: [], closests: [] };
    var diff = this.clone().sub(line.origin);
    var lineParameter = line.direction.dot(diff);
    var lineClosest = line.direction
      .clone()
      .multiplyScalar(lineParameter)
      .add(line.origin);

    result.parameters!.push(0, lineParameter);
    result.closests!.push(this, lineClosest);

    diff = result.closests![0].clone().sub(result.closests![1]);
    result.distanceSqr = diff.dot(diff);
    result.distance = Math.sqrt(result.distanceSqr);
    return result;
  }

  /**
 * Test success
 * 到射线的距离
 * @param  {Line} line
 * @returns {Object} lineParameter 最近点的参数  lineClosest 最近点  distanceSqr 到最近点距离的平方  distance 到最近点距离
 */
  distanceRay(ray: Ray) {
    var result: DistanceResult = {
      parameters: [0],
      closests: [this]
    };
    var diff = this.clone().sub(ray.origin);
    result.parameters![1] = ray.direction.dot(diff);

    if (result.parameters![1] > 0) {
      result.closests![1] = ray.direction
        .clone()
        .multiplyScalar(result.parameters![1])
        .add(ray.origin);
    } else {
      result.closests![1] = ray.origin.clone();
    }
    diff = this.clone().sub(result.closests![1]);
    result.distanceSqr = diff.dot(diff);
    result.distance = Math.sqrt(result.distanceSqr);

    return result;
  }

  /**
  * Test success
  * 到线段的距离
  * @param  {Line} line
  * @returns {Object} lineParameter 最近点的参数  lineClosest 最近点  distanceSqr 到最近点距离的平方  distance 到最近点距离
  */
  distanceSegment(segment: Segment) {
    const result: DistanceResult = {
      parameters: [],
      closests: []
    };

    var diff = this.clone().sub(segment.p1);
    var t = segment.extentDirection.dot(diff);

    if (t >= 0) {
      result.parameters![1] = 1;
      result.closests![1] = segment.p1;
    } else {
      diff = this.clone().sub(segment.p0);
      t = segment.extentDirection.dot(diff);
      if (t <= 0) {
        result.parameters![1] = 0;
        result.closests![1] = segment.p0;
      }
      else {
        var sqrLength = segment.extentSqr;
        if (sqrLength <= 0)
          sqrLength = 0;

        t /= sqrLength;
        result.parameters![1] = t;
        result.closests![1] = segment.extentDirection
          .clone()
          .multiplyScalar(t)
          .add(segment.p0);
      }
    }

    result.closests![0] = this;
    diff = this.clone().sub(result.closests![1]);
    result.distanceSqr = diff.dot(diff);
    result.distance = Math.sqrt(result.distanceSqr);

    return result;
  }

  /**
   * 点与线段的距离
   * @param plane 
   */
  distancePlane(plane: Plane) {
    // this.clone().sub(plane.origin).dot(plane.normal);
    const result: DistanceResult = {
      parameters: [],
      closests: [],
      signedDistance: 0,
      distance: 0
    };
    result.signedDistance = this.clone().dot(plane.normal) - plane.w;
    result.distance = Math.abs(result.signedDistance);
    result.closests![1] = this.clone().sub(plane.normal.clone().multiplyScalar(result.signedDistance));
    return result;
  }


  /**
   * 点与圆圈的距离
   * @param {*} circle 
   * @param {*} disk 
   * @returns {} result
   */
  distanceCircle(circle: Circle) {
    var result: DistanceResult = {
      parameters: [],
      closests: [],
      equidistant: false//是否等距
    };

    // Projection of P-C onto plane is Q-C = P-C - Dot(N,P-C)*N.

    var PmC = this.clone().sub(circle.center);
    var QmC = PmC.clone().sub(circle.normal.clone().multiplyScalar(circle.normal.dot(PmC)));
    var lengthQmC = QmC.length();
    if (lengthQmC > delta4) {
      result.circleClosest = QmC.clone().multiplyScalar(circle.radius / lengthQmC).add(circle.center);
      result.equidistant = false;
    }
    else {
      var offsetPoint = circle.center.clone().add(v3(10, 10, 10));
      var CP = offsetPoint.sub(circle.center);
      var CQ = CP.clone().sub(circle.normal.clone().multiplyScalar(circle.normal.dot(CP))).normalize()
      //在圆圈圆心的法线上，到圆圈上的没一点都相同 
      result.circleClosest = CQ.clone().multiplyScalar(circle.radius).add(circle.center)
      result.equidistant = true;
    }
    result.closests!.push(this, result.circleClosest);
    var diff = this.clone().sub(result.circleClosest);
    result.distanceSqr = diff.dot(diff);
    result.distance = Math.sqrt(result.distanceSqr);

    return result;
  }


  /**
  * 点与圆盘的距离 
  * @param {*} Disk 
  * @returns {} result
  */
  distanceDisk(disk: Disk): DistanceResult {
    var result: DistanceResult = {
      parameters: [],
      closests: [],
      signedDistance: 1,
      distanceSqr: 0,
      distance: 0,
    };

    var PmC = this.clone().sub(disk.center);
    var QmC = PmC.clone().sub(disk.normal.clone().multiplyScalar(disk.normal.dot(PmC)));
    var lengthQmC = QmC.length();

    result.signedDistance = this.clone().dot(disk.normal) - disk.w;

    if (lengthQmC > disk.radius) {
      result.diskClosest = QmC.clone().multiplyScalar(disk.radius / lengthQmC).add(disk.center);
    }
    else {
      var signedDistance = this.clone().dot(disk.normal) - disk.w;
      result.diskClosest = this.clone().sub(disk.normal.clone().multiplyScalar(signedDistance));
    }
    result.closests!.push(this, result.diskClosest);
    var diff = this.clone().sub(result.diskClosest);
    result.distanceSqr = diff.dot(diff);
    result.distance = Math.sqrt(result.distanceSqr);
    return result;
  }
  /**
   * 点与线段的距离
   * 点与折线的距离 测试排除法，平均比线性检索(暴力法)要快两倍以上
   * @param { Polyline | Vec3[]} polyline 
   */
  distancePolyline(polyline: Polyline<Vec3> | Vec3[]) {
    let u = +Infinity;
    let ipos: number = -1;
    let tempResult: DistanceResult;
    let result = null;
    for (let i = 0; i < polyline.length - 1; i++) {
      let pti, ptj;
      if (Array.isArray(polyline)) {
        pti = polyline[i];
        ptj = polyline[i + 1];
      }
      else {
        pti = polyline.get(i);
        ptj = polyline.get(i + 1);
      }
      if (Math.abs(pti.x - this._x) > u && Math.abs(ptj.x - this._x) > u && (pti.x - this._x) * (ptj.x - this._x) > 0)
        continue;
      if (Math.abs(pti.y - this._y) > u && Math.abs(ptj.y - this._y) > u && (pti.y - this._y) * (ptj.y - this._y) > 0)
        continue;
      if (Math.abs(pti.z - this._z) > u && Math.abs(ptj.z - this._z) > u && (pti.z - this._z) * (ptj.z - this._z) > 0)
        continue;
      tempResult = this.distanceSegment(new Segment(pti, ptj));
      if (tempResult.distance! < u) {
        u = tempResult.distance!;
        result = tempResult;
        ipos = i;
      }
    }

    result!.segmentIndex = ipos;
    return result;
  }

  /**
   * 点到三角形的距离
   * @param {Triangle} triangle 
   */
  distanceTriangle(triangle: Triangle): DistanceResult {

    function GetMinEdge02(a11: any, b1: any, p: any) {
      p[0] = 0;
      if (b1 >= 0) {
        p[1] = 0;
      }
      else if (a11 + b1 <= 0) {
        p[1] = 1;
      }
      else {
        p[1] = -b1 / a11;
      }
    }

    function GetMinEdge12(a01: number, a11: number, b1: number, f10: number, f01: number, p: any) {
      var h0 = a01 + b1 - f10;
      if (h0 >= 0) {
        p[1] = 0;
      }
      else {
        var h1 = a11 + b1 - f01;
        if (h1 <= 0) {
          p[1] = 1;
        }
        else {
          p[1] = h0 / (h0 - h1);
        }
      }
      p[0] = 1 - p[1];
    }

    function GetMinInterior(p0: any, h0: number, p1: any, h1: number, p: any) {
      var z = h0 / (h0 - h1);
      p[0] = (1 - z) * p0[0] + z * p1[0];
      p[1] = (1 - z) * p0[1] + z * p1[1];
    }

    var diff = this.clone().sub(triangle.p0);
    var edge0 = triangle.p1.clone().sub(triangle.p0);
    var edge1 = triangle.p2.clone().sub(triangle.p0);
    var a00 = edge0.dot(edge0);
    var a01 = edge0.dot(edge1);
    var a11 = edge1.dot(edge1);
    var b0 = -diff.dot(edge0);
    var b1 = -diff.dot(edge1);

    var f00 = b0;
    var f10 = b0 + a00;
    var f01 = b0 + a01;

    var p0 = [0, 0], p1 = [0, 0], p = [0, 0];
    var dt1, h0, h1;


    if (f00 >= 0) {
      if (f01 >= 0) {
        // (1) p0 = (0,0), p1 = (0,1), H(z) = G(L(z))
        GetMinEdge02(a11, b1, p);
      }
      else {
        // (2) p0 = (0,t10), p1 = (t01,1-t01),
        // H(z) = (t11 - t10)*G(L(z))
        p0[0] = 0;
        p0[1] = f00 / (f00 - f01);
        p1[0] = f01 / (f01 - f10);
        p1[1] = 1 - p1[0];
        dt1 = p1[1] - p0[1];
        h0 = dt1 * (a11 * p0[1] + b1);
        if (h0 >= 0) {
          GetMinEdge02(a11, b1, p);
        }
        else {
          h1 = dt1 * (a01 * p1[0] + a11 * p1[1] + b1);
          if (h1 <= 0) {
            GetMinEdge12(a01, a11, b1, f10, f01, p);
          }
          else {
            GetMinInterior(p0, h0, p1, h1, p);
          }
        }
      }
    }
    else if (f01 <= 0) {
      if (f10 <= 0) {
        // (3) p0 = (1,0), p1 = (0,1),
        // H(z) = G(L(z)) - F(L(z))
        GetMinEdge12(a01, a11, b1, f10, f01, p);
      }
      else {
        // (4) p0 = (t00,0), p1 = (t01,1-t01), H(z) = t11*G(L(z))
        p0[0] = f00 / (f00 - f10);
        p0[1] = 0;
        p1[0] = f01 / (f01 - f10);
        p1[1] = 1 - p1[0];
        h0 = p1[1] * (a01 * p0[0] + b1);
        if (h0 >= 0) {
          p = p0;  // GetMinEdge01
        }
        else {
          h1 = p1[1] * (a01 * p1[0] + a11 * p1[1] + b1);
          if (h1 <= 0) {
            GetMinEdge12(a01, a11, b1, f10, f01, p);
          }
          else {
            GetMinInterior(p0, h0, p1, h1, p);
          }
        }
      }
    }
    else if (f10 <= 0) {
      // (5) p0 = (0,t10), p1 = (t01,1-t01),
      // H(z) = (t11 - t10)*G(L(z))
      p0[0] = 0;
      p0[1] = f00 / (f00 - f01);
      p1[0] = f01 / (f01 - f10);
      p1[1] = 1 - p1[0];
      dt1 = p1[1] - p0[1];
      h0 = dt1 * (a11 * p0[1] + b1);
      if (h0 >= 0) {
        GetMinEdge02(a11, b1, p);
      }
      else {
        h1 = dt1 * (a01 * p1[0] + a11 * p1[1] + b1);
        if (h1 <= 0) {
          GetMinEdge12(a01, a11, b1, f10, f01, p);
        }
        else {
          GetMinInterior(p0, h0, p1, h1, p);
        }
      }
    }
    else {
      // (6) p0 = (t00,0), p1 = (0,t11), H(z) = t11*G(L(z))
      p0[0] = f00 / (f00 - f10);
      p0[1] = 0;
      p1[0] = 0;
      p1[1] = f00 / (f00 - f01);
      h0 = p1[1] * (a01 * p0[0] + b1);
      if (h0 >= 0) {
        p = p0;  // GetMinEdge01
      }
      else {
        h1 = p1[1] * (a11 * p1[1] + b1);
        if (h1 <= 0) {
          GetMinEdge02(a11, b1, p);
        }
        else {
          GetMinInterior(p0, h0, p1, h1, p);
        }
      }
    }

    var result: DistanceResult = {
      closests: [],
      parameters: [],
      triangleParameters: []
    };
    result.triangleParameters![0] = 1 - p[0] - p[1];
    result.triangleParameters![1] = p[0];
    result.triangleParameters![2] = p[1];
    var closest = triangle.p0.clone().add(edge0.multiplyScalar(p[0])).add(edge1.multiplyScalar(p[1]));
    result.parameters!.push(0, result.triangleParameters);
    result.closests!.push(this, closest);
    diff = this.clone().sub(closest);
    result.distanceSqr = diff.dot(diff);
    result.distance = Math.sqrt(result.distanceSqr);
    return result;
  }

  /**
   * 点到矩形的距离
   * @param  {Rectangle} rectangle
   */
  distanceRectangle(rectangle: Rectangle): DistanceResult {
    var result: DistanceResult = {
      rectangleParameters: [],
      parameters: [],
      closests: [],
    };


    var diff = rectangle.center.clone().sub(this);
    var b0 = diff.dot(rectangle.axis[0]);
    var b1 = diff.dot(rectangle.axis[1]);
    var s0 = -b0, s1 = -b1;
    result.distanceSqr = diff.dot(diff);

    if (s0 < -rectangle.extent[0]) {
      s0 = -rectangle.extent[0];
    }
    else if (s0 > rectangle.extent[0]) {
      s0 = rectangle.extent[0];
    }
    result.distanceSqr += s0 * (s0 + 2 * b0);

    if (s1 < -rectangle.extent[1]) {
      s1 = -rectangle.extent[1];
    }
    else if (s1 > rectangle.extent[1]) {
      s1 = rectangle.extent[1];
    }
    result.distanceSqr += s1 * (s1 + 2 * b1);

    // Account for numerical round-off error.
    if (result.distanceSqr < 0) {
      result.distanceSqr = 0;
    }

    result.distance = Math.sqrt(result.distanceSqr);
    result.rectangleParameters![0] = s0;
    result.rectangleParameters![1] = s1;
    var rectangleClosestPoint = rectangle.center.clone();
    for (var i = 0; i < 2; ++i) {
      rectangleClosestPoint.add(rectangle.axis[i].multiplyScalar(result.rectangleParameters![i]));
    }
    result.closests![0] = this;
    result.closests![1] = rectangleClosestPoint;
    return result;
  }

  /**
  * 点到胶囊的距离
  * @param {Capsule} capsule 
  */
  distanceCapsule(capsule: Capsule): DistanceResult {
    var result = this.distanceSegment(capsule);
    result.distance = result.distance! - capsule.radius;
    var closest = this.clone().sub(result.closests![1]).normalize().multiplyScalar(capsule.radius);
    result.interior = result.distance < 0;

    result.closests = [this, closest];
    return result;
  }

  //---Intersection-------------------------------------------------------------------------------
}

const _vec = v3();
const _quat: Quat = quat();

export function v3(x?: number, y?: number, z?: number) {
  return new Vec3(x, y, z);
}