const Bound = require('./rectbound').Bound;
//type: enum ZoneType { ZONE_NONE, ZONE_NORMAL, ZONE_EXCLUSION, ZONE_DISPLAY, ZONE_VFR };
const zoneType = Object.freeze({ "NONE": 0, "NORMAL": 1, "XCL": 2 });

let zone = function (id, name, type, points, hasLines = false) {
  this.init();
  if (points && points.length) {
    this.points = points;
    // Update bounding box
    for (let i = 0; i < this.points.length; i++) {
      this.bounds.updateP(this.points[i]);
    }
  }
  this.id = id;
  this.name = name;
  this.type = type;
  this.hasLines = hasLines;
  this.bbox = [this.bounds.xmin, this.bounds.ymin, this.bounds.xmax, this.bounds.ymax];
}

zone.prototype.init = function () {
  this.points = [];
  this.bounds = new Bound();
  this.type = zoneType.NORMAL;
}

// zone.prototype.toClockwiseOrder = function () {
// if (this.area() > 0 && this.points.length >= 4) {
//   const max = div(count(), 2).quot + 1, j = 0;
//   exchange(0, 1);
//   for (int i = 2; i < max; i++) {
//     exchange(i, (count() - 1) - j);
//     j++;
//   }
//   return 1;
// }
// return 0;
// }

zone.prototype.updateBounds = function () {
  this.bounds.init();
  for (let i = 0; i < this.points.length; i++)
    this.bounds.updateP(this.points[i]);
}

zone.prototype.area = function () {
  let _area = 0, n = this.points.length;
  if (n < 3)
    return 0; // not a polygon
  let j;
  for (let i = 0; i < n; i++) {
    j = (i + 1) % n;
    _area += this.points[i].x * this.points[j].y;
    _area -= this.points[i].y * this.points[j].x;
  }
  return _area * 0.5;
}

module.exports = { Zone: zone, Type: zoneType }