[SIP-5] Refactor MapBox (#5783)

* Break MapBox into smaller pieces

* Replace React.createElement with regular jsx

* detach setControlValue

* enable render trigger

* Pass explicit props rather than pass all that exists in payload.data. Also use formData when possible.

* Rename sliceWidth, sliceHeight to width, height. Use deconstructor. Extract function.

* use arrow function

* fix linting and remove css

superset/assets/src/visualizations/MapBox/MapBox.jsx

@@ -0,0 +1,225 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import ReactDOM from 'react-dom';
+import MapGL from 'react-map-gl';
+import Immutable from 'immutable';
+import supercluster from 'supercluster';
+import ViewportMercator from 'viewport-mercator-project';
+import ScatterPlotGlowOverlay from './ScatterPlotGlowOverlay';
+
+import {
+  DEFAULT_LONGITUDE,
+  DEFAULT_LATITUDE,
+  DEFAULT_ZOOM,
+} from '../../utils/common';
+import './MapBox.css';
+
+const NOOP = () => {};
+const DEFAULT_POINT_RADIUS = 60;
+const DEFAULT_MAX_ZOOM = 16;
+
+const propTypes = {
+  width: PropTypes.number,
+  height: PropTypes.number,
+  aggregatorName: PropTypes.string,
+  clusterer: PropTypes.object,
+  globalOpacity: PropTypes.number,
+  mapStyle: PropTypes.string,
+  mapboxApiKey: PropTypes.string,
+  onViewportChange: PropTypes.func,
+  pointRadius: PropTypes.number,
+  pointRadiusUnit: PropTypes.string,
+  renderWhileDragging: PropTypes.bool,
+  rgb: PropTypes.array,
+  viewportLatitude: PropTypes.number,
+  viewportLongitude: PropTypes.number,
+  viewportZoom: PropTypes.number,
+};
+
+const defaultProps = {
+  globalOpacity: 1,
+  onViewportChange: NOOP,
+  pointRadius: DEFAULT_POINT_RADIUS,
+  pointRadiusUnit: 'Pixels',
+  viewportLatitude: DEFAULT_LATITUDE,
+  viewportLongitude: DEFAULT_LONGITUDE,
+  viewportZoom: DEFAULT_ZOOM,
+};
+
+class MapBox extends React.Component {
+  constructor(props) {
+    super(props);
+
+    const {
+      viewportLatitude: latitude,
+      viewportLongitude: longitude,
+      viewportZoom: zoom,
+    } = this.props;
+
+    this.state = {
+      viewport: {
+        longitude,
+        latitude,
+        zoom,
+        startDragLngLat: [longitude, latitude],
+      },
+    };
+    this.onViewportChange = this.onViewportChange.bind(this);
+  }
+
+  onViewportChange(viewport) {
+    this.setState({ viewport });
+    this.props.onViewportChange(viewport);
+  }
+
+  render() {
+    const {
+      width,
+      height,
+      aggregatorName,
+      globalOpacity,
+      mapStyle,
+      mapboxApiKey,
+      pointRadius,
+      pointRadiusUnit,
+      renderWhileDragging,
+      rgb,
+    } = this.props;
+    const { viewport } = this.state;
+    const { latitude, longitude, zoom } = viewport;
+    const mercator = new ViewportMercator({
+      width,
+      height,
+      longitude,
+      latitude,
+      zoom,
+    });
+    const topLeft = mercator.unproject([0, 0]);
+    const bottomRight = mercator.unproject([width, height]);
+    const bbox = [topLeft[0], bottomRight[1], bottomRight[0], topLeft[1]];
+    const clusters = this.props.clusterer.getClusters(bbox, Math.round(zoom));
+    const isDragging = viewport.isDragging === undefined ? false :
+                       viewport.isDragging;
+    return (
+      <MapGL
+        {...this.state.viewport}
+        mapStyle={mapStyle}
+        width={width}
+        height={height}
+        mapboxApiAccessToken={mapboxApiKey}
+        onViewportChange={this.onViewportChange}
+      >
+        <ScatterPlotGlowOverlay
+          {...viewport}
+          isDragging={isDragging}
+          width={width}
+          height={height}
+          locations={Immutable.fromJS(clusters)}
+          dotRadius={pointRadius}
+          pointRadiusUnit={pointRadiusUnit}
+          rgb={rgb}
+          globalOpacity={globalOpacity}
+          compositeOperation={'screen'}
+          renderWhileDragging={renderWhileDragging}
+          aggregatorName={aggregatorName}
+          lngLatAccessor={(location) => {
+            const coordinates = location.get('geometry').get('coordinates');
+            return [coordinates.get(0), coordinates.get(1)];
+          }}
+        />
+      </MapGL>
+    );
+  }
+}
+
+MapBox.propTypes = propTypes;
+MapBox.defaultProps = defaultProps;
+
+function createReducer(aggregatorName, customMetric) {
+  if (aggregatorName === 'sum' || !customMetric) {
+    return (a, b) => a + b;
+  } else if (aggName === 'min') {
+    return Math.min;
+  } else if (aggName === 'max') {
+    return Math.max;
+  }
+  return function (a, b) {
+    if (a instanceof Array) {
+      if (b instanceof Array) {
+        return a.concat(b);
+      }
+      a.push(b);
+      return a;
+    }
+    if (b instanceof Array) {
+      b.push(a);
+      return b;
+    }
+    return [a, b];
+  };
+}
+
+function mapbox(slice, payload, setControlValue) {
+  const { formData, selector } = slice;
+  const {
+    customMetric,
+    geoJSON,
+    mapboxApiKey,
+  } = payload.data;
+  const {
+    clustering_radius: clusteringRadius,
+    global_opacity: globalOpacity,
+    mapbox_color: color,
+    mapbox_style: mapStyle,
+    pandas_aggfunc: aggregatorName,
+    point_radius: pointRadius,
+    point_radius_unit: pointRadiusUnit,
+    render_while_dragging: renderWhileDragging,
+    viewport_latitude: viewportLatitude,
+    viewport_longitude: viewportLongitude,
+    viewport_zoom: viewportZoom,
+  } = formData;
+
+  // Validate mapbox color
+  const rgb = /^rgb\((\d{1,3}),\s*(\d{1,3}),\s*(\d{1,3})\)$/
+    .exec(color);
+  if (rgb === null) {
+    slice.error('Color field must be of form \'rgb(%d, %d, %d)\'');
+    return;
+  }
+
+  const clusterer = supercluster({
+    radius: clusteringRadius,
+    maxZoom: DEFAULT_MAX_ZOOM,
+    metricKey: 'metric',
+    metricReducer: createReducer(aggregatorName, customMetric),
+  });
+  clusterer.load(geoJSON.features);
+
+  ReactDOM.render(
+    <MapBox
+      width={slice.width()}
+      height={slice.height()}
+      aggregatorName={aggregatorName}
+      clusterer={clusterer}
+      globalOpacity={globalOpacity}
+      mapStyle={mapStyle}
+      mapboxApiKey={mapboxApiKey}
+      onViewportChange={({ latitude, longitude, zoom }) => {
+        setControlValue('viewport_longitude', longitude);
+        setControlValue('viewport_latitude', latitude);
+        setControlValue('viewport_zoom', zoom);
+      }}
+      pointRadius={pointRadius === 'Auto' ? DEFAULT_POINT_RADIUS : pointRadius}
+      pointRadiusUnit={pointRadiusUnit}
+      renderWhileDragging={renderWhileDragging}
+      rgb={rgb}
+      viewportLatitude={viewportLatitude}
+      viewportLongitude={viewportLongitude}
+      viewportZoom={viewportZoom}
+    />,
+    document.querySelector(selector),
+  );
+}
+
+export default mapbox;