<template>
    <div @click="togglePolygonTool" class="toolbar-button">
        <i :class="['fa fa-edit', {inverted: polygonTool && polygonTool.getActive()}]"></i>
    </div>
</template>

<script>
/* This is Free Software under GNU Affero General Public License v >= 3.0
 * without warranty, see README.md and license for details.
 *
 * SPDX-License-Identifier: AGPL-3.0-or-later
 * License-Filename: LICENSES/AGPL-3.0.txt
 *
 * Copyright (C) 2018 by via donau
 *   – Österreichische Wasserstraßen-Gesellschaft mbH
 * Software engineering by Intevation GmbH
 *
 * Author(s):
 * Markus Kottländer <markus.kottlaender@intevation.de>
 */
import { mapState, mapGetters } from "vuex";
import { getArea } from "ol/sphere.js";
import Draw from "ol/interaction/Draw.js";

export default {
  name: "polygontool",
  computed: {
    ...mapGetters("map", ["getLayerByName"]),
    ...mapState("map", ["lineTool", "polygonTool", "cutTool", "openLayersMap"])
  },
  methods: {
    togglePolygonTool() {
      this.polygonTool.setActive(!this.polygonTool.getActive());
      this.lineTool.setActive(false);
      this.cutTool.setActive(false);
      this.$store.commit("map/setCurrentMeasurement", null);
      this.getLayerByName("Draw Tool")
        .data.getSource()
        .clear();
    },
    polygonEnd(event) {
      const areaSize = getArea(event.feature.getGeometry());
      this.$store.commit("map/setCurrentMeasurement", {
        quantity: "Area",
        unitSymbol: areaSize > 100000 ? "km²" : "m²",
        value:
          areaSize > 100000
            ? Math.round(areaSize / 1000) / 1000 // convert into 1 km² == 1000*1000 m² and round to 1000 m²
            : Math.round(areaSize)
      });
      this.$store.commit("application/showIdentify", true);
    }
  },
  created() {
    if (!this.polygonTool) {
      const drawVectorSrc = this.getLayerByName("Draw Tool").data.getSource();
      const polygonTool = new Draw({
        source: drawVectorSrc,
        type: "Polygon",
        maxPoints: 50
      });
      polygonTool.setActive(false);
      polygonTool.on("drawstart", () => {
        drawVectorSrc.clear();
        this.$store.commit("map/setCurrentMeasurement", null);
      });
      polygonTool.on("drawend", this.polygonEnd);
      this.$store.commit("map/polygonTool", polygonTool);
      this.openLayersMap.addInteraction(polygonTool);
    }
  }
};
</script>