// deck.gl-community
// SPDX-License-Identifier: MIT
// Copyright (c) vis.gl contributors

import distance from '@turf/distance';
import ellipse from '@turf/ellipse';
import bearing from '@turf/bearing';
import {point} from '@turf/helpers';
import {PointerMoveEvent} from '../edit-modes/types';
import {EditAction, getIntermediatePosition} from './mode-handler';
import {ThreeClickPolygonHandler} from './three-click-polygon-handler';

// TODO edit-modes: delete handlers once EditMode fully implemented
export class DrawEllipseUsingThreePointsHandler extends ThreeClickPolygonHandler {
  handlePointerMove(event: PointerMoveEvent): {
    editAction: EditAction | null | undefined;
    cancelMapPan: boolean;
  } {
    const result = {editAction: null, cancelMapPan: false};
    const clickSequence = this.getClickSequence();

    if (clickSequence.length === 0) {
      // nothing to do yet
      return result;
    }

    const mapCoords = event.mapCoords;

    if (clickSequence.length === 1) {
      this._setTentativeFeature({
        type: 'Feature',
        geometry: {
          type: 'LineString',
          coordinates: [clickSequence[0], mapCoords]
        },
        properties: {}
      });
    } else if (clickSequence.length === 2) {
      const [p1, p2] = clickSequence;

      const centerCoordinates = getIntermediatePosition(p1, p2);
      const xSemiAxis = Math.max(distance(centerCoordinates, point(mapCoords)), 0.001);
      const ySemiAxis = Math.max(distance(p1, p2), 0.001) / 2;
      const options = {angle: bearing(p1, p2)};

      this._setTentativeFeature(ellipse(centerCoordinates, xSemiAxis, ySemiAxis, options));
    }

    return result;
  }
}