splitPolygon()

in modules/edit-modes/src/lib/split-polygon-mode.ts [148:200]

• 40 lines of code
• 5 McCabe index (conditional complexity)

  splitPolygon(tentativeFeature: TentativeFeature, props: ModeProps<FeatureCollection>) {
    const selectedGeometry = this.getSelectedGeometry(props);
    const featureIndex = props.selectedIndexes[0];
    const modeConfig = props.modeConfig || {};

    // Default gap in between the polygon
    let { gap = 0.1, units = 'centimeters' } = modeConfig;
    if (gap === 0) {
      gap = 0.1;
      units = 'centimeters';
    }

    const buffer = turfBuffer(tentativeFeature, gap, { units });
    // @ts-expect-error turf types diff
    const updatedGeometry = turfDifference(selectedGeometry, buffer);
    if (!updatedGeometry) {
      // eslint-disable-next-line no-console,no-undef
      console.warn('Canceling edit. Split Polygon erased');
      return null;
    }

    const { type, coordinates } = updatedGeometry.geometry;
    let updatedCoordinates = [];
    if (type === 'Polygon') {
      // Update the coordinates as per Multipolygon
      updatedCoordinates = coordinates.map((c) => [c]);
    } else {
      // Handle Case when Multipolygon has holes
      updatedCoordinates = coordinates.reduce((agg, prev) => {
        prev.forEach((p) => {
          // @ts-expect-error revisit coordinates type here
          agg.push([p]);
        });
        return agg;
      }, []);
    }

    // Update the type to Mulitpolygon
    const updatedData = new ImmutableFeatureCollection(props.data).replaceGeometry(featureIndex, {
      type: 'MultiPolygon',
      coordinates: updatedCoordinates,
    });

    const editAction: GeoJsonEditAction = {
      updatedData: updatedData.getObject(),
      editType: 'split',
      editContext: {
        featureIndexes: [featureIndex],
      },
    };

    return editAction;
  }