import { defined } from "../../Source/Cesium.js";
import { JulianDate } from "../../Source/Cesium.js";
import { Math as CesiumMath } from "../../Source/Cesium.js";
import { Matrix3 } from "../../Source/Cesium.js";
import { Simon1994PlanetaryPositions as PlanetaryPositions } from "../../Source/Cesium.js";
import { TimeStandard } from "../../Source/Cesium.js";
import { Transforms } from "../../Source/Cesium.js";

describe("Core/Simon1994PlanetaryPositions", function () {
  // Values for the X Y and Z were found using the STK Components GeometryTransformer on the position of the
  // sun center of mass point and the earth J2000 reference frame.
  it("computes correct sun position", function () {
    var date = new JulianDate(2451545, 0, TimeStandard.TAI);
    var sun = PlanetaryPositions.computeSunPositionInEarthInertialFrame(date);
    var X = 26500268539.790234;
    var Y = -132756447253.27325;
    var Z = -57556483362.533806;
    expect(X).toEqualEpsilon(sun.x, CesiumMath.EPSILON2);
    expect(Y).toEqualEpsilon(sun.y, CesiumMath.EPSILON2);
    expect(Z).toEqualEpsilon(sun.z, CesiumMath.EPSILON2);

    date = new JulianDate(2456401.5, 0, TimeStandard.TAI);
    sun = PlanetaryPositions.computeSunPositionInEarthInertialFrame(date);
    X = 131512388940.33589;
    Y = 66661342667.949928;
    Z = 28897975607.905258;
    expect(X).toEqualEpsilon(sun.x, CesiumMath.EPSILON3);
    expect(Y).toEqualEpsilon(sun.y, CesiumMath.EPSILON3);
    expect(Z).toEqualEpsilon(sun.z, CesiumMath.EPSILON3);

    date = new JulianDate(2455998.591667, 0, TimeStandard.TAI);
    sun = PlanetaryPositions.computeSunPositionInEarthInertialFrame(date);
    X = 147109989956.19534;
    Y = -19599996881.217579;
    Z = -8497578102.7696457;
    expect(X).toEqualEpsilon(sun.x, CesiumMath.EPSILON3);
    expect(Y).toEqualEpsilon(sun.y, CesiumMath.EPSILON3);
    expect(Z).toEqualEpsilon(sun.z, CesiumMath.EPSILON3);
  });

  // Values for X Y and Z were found using the STK Components GeometryTransformer on the Simon 1994 moon point and the earth
  // J2000 reference frame.
  it("computes correct moon position", function () {
    var date = new JulianDate(2451545.0, 0, TimeStandard.TAI);
    var moon = PlanetaryPositions.computeMoonPositionInEarthInertialFrame(date);
    var X = -291632410.61232185;
    var Y = -266522146.36821631;
    var Z = -75994518.081043154;
    expect(X).toEqualEpsilon(moon.x, CesiumMath.EPSILON4);
    expect(Y).toEqualEpsilon(moon.y, CesiumMath.EPSILON4);
    expect(Z).toEqualEpsilon(moon.z, CesiumMath.EPSILON4);

    date = new JulianDate(2456401.5, 0, TimeStandard.TAI);
    moon = PlanetaryPositions.computeMoonPositionInEarthInertialFrame(date);
    X = -223792974.4736526;
    Y = 315772435.34490639;
    Z = 97913011.236112773;
    expect(X).toEqualEpsilon(moon.x, CesiumMath.EPSILON4);
    expect(Y).toEqualEpsilon(moon.y, CesiumMath.EPSILON4);
    expect(Z).toEqualEpsilon(moon.z, CesiumMath.EPSILON4);

    date = new JulianDate(2455998.591667, 0, TimeStandard.TAI);
    moon = PlanetaryPositions.computeMoonPositionInEarthInertialFrame(date);
    X = -268426117.00202647;
    Y = -220468861.73998192;
    Z = -110670164.58446842;
    expect(X).toEqualEpsilon(moon.x, CesiumMath.EPSILON4);
    expect(Y).toEqualEpsilon(moon.y, CesiumMath.EPSILON4);
    expect(Z).toEqualEpsilon(moon.z, CesiumMath.EPSILON4);
  });

  it("has the sun rising in the east and setting in the west", function () {
    //Julian dates for 24 hours, starting from July 6th 2011 @ 01:00 UTC
    var transformMatrix = new Matrix3();
    var timesOfDay = [];
    var i;
    for (i = 1; i < 25; i++) {
      var date = new Date("July 6, 2011");
      date.setUTCHours(i, 0, 0, 0);
      timesOfDay.push(JulianDate.fromDate(date));
    }
    var angles = [];
    for (i = 0; i < 24; i++) {
      transformMatrix = Transforms.computeIcrfToFixedMatrix(
        timesOfDay[i],
        transformMatrix
      );
      if (!defined(transformMatrix)) {
        transformMatrix = Transforms.computeTemeToPseudoFixedMatrix(
          timesOfDay[i],
          transformMatrix
        );
      }
      var position = PlanetaryPositions.computeSunPositionInEarthInertialFrame(
        timesOfDay[i]
      );
      Matrix3.multiplyByVector(transformMatrix, position, position);
      angles.push(
        CesiumMath.convertLongitudeRange(Math.atan2(position.y, position.x))
      );
    }
    //Expect a clockwise motion.
    for (i = 1; i < 24; i++) {
      expect(angles[i]).toBeLessThan(angles[i - 1]);
    }
  });

  it("works without a time", function () {
    PlanetaryPositions.computeSunPositionInEarthInertialFrame(undefined);
  });
});