feat(theme): add dark theme

The Dark Theme is now available.
The AxisConfig has now a cleaner styling, splitted by axis or tick styles.
Changing a theme is now easier and it's not necessary tied to a darkmode flag. New
theme can be added and used on the charts.

fix #35

BREAKING CHANGE: The `Theme.AxisConfig` type has a different signature.
It now contains `axisTitleStyle`, `axisLineStyle`, `tickLabelStyle` and
`tickLineStyle` defined as `TextStyle` or `StrokeStyle` elements.
The `Theme` interface is changed in a more flat structure.
`darkMode` prop from `Setting` is removed.
`theme` prop in `Setting` is now a `Theme` type object, not a `PartialTheme`.
You can use `mergeWithDefaultTheme` function to merge an existing theme
with a partial one.

.storybook/config.ts

@@ -4,7 +4,7 @@ import { withKnobs } from '@storybook/addon-knobs';
 import { withOptions } from '@storybook/addon-options';
 import { addDecorator, configure } from '@storybook/react';
 import '../src/index.scss';
-import './style.css';
+import './style.scss';
 
 addDecorator(
   withOptions({

.storybook/style.css → .storybook/style.scss

@@ -1,6 +1,11 @@
+@import '../node_modules/@elastic/eui/src/themes/eui/eui_colors_dark.scss';
+
 .story-chart {
   background: white;
 }
+.story-chart-dark {
+  background: $euiColorEmptyShade;
+}
 #root {
   background-color: blanchedalmond;
 }
@@ -21,3 +26,6 @@
   border: 1px solid gray;
   padding: 5px;
 }
+.Pane.vertical.Pane1 {
+  background: red;
+}

src/components/_legend.scss

@@ -1,5 +1,5 @@
-$elasticChartsLegendMaxWidth: $euiSize * 10 + $euiSize;
-$elasticChartsLegendMaxHeight: $euiSize * 4 + $euiSize;
+$elasticChartsLegendMaxWidth: $euiSize * 10;
+$elasticChartsLegendMaxHeight: $euiSize * 4;
 
 .elasticChartsLegend {
   position: absolute;

src/components/legend.tsx

@@ -48,13 +48,13 @@ class LegendComponent extends React.Component<ReactiveChartProps> {
     let paddingStyle;
     if (isVertical(legendPosition)) {
       paddingStyle = {
-        paddingTop: chartTheme.chart.margins.top,
-        paddingBottom: chartTheme.chart.margins.bottom,
+        paddingTop: chartTheme.chartMargins.top,
+        paddingBottom: chartTheme.chartMargins.bottom,
       };
     } else {
       paddingStyle = {
-        paddingLeft: chartTheme.chart.margins.left,
-        paddingRight: chartTheme.chart.margins.right,
+        paddingLeft: chartTheme.chartMargins.left,
+        paddingRight: chartTheme.chartMargins.right,
       };
     }
     return (

src/components/react_canvas/area_geometries.tsx

@@ -4,15 +4,21 @@ import React from 'react';
 import { Circle, Group, Path } from 'react-konva';
 import { animated, Spring } from 'react-spring/konva';
 import { LegendItem } from '../../lib/series/legend';
-import { AreaGeometry, GeometryValue, getGeometryStyle, PointGeometry } from '../../lib/series/rendering';
-import { AreaSeriesStyle } from '../../lib/themes/theme';
+import {
+  AreaGeometry,
+  GeometryValue,
+  getGeometryStyle,
+  PointGeometry,
+} from '../../lib/series/rendering';
+import { AreaSeriesStyle, SharedGeometryStyle } from '../../lib/themes/theme';
 import { ElementClickListener, TooltipData } from '../../state/chart_state';
 
 interface AreaGeometriesDataProps {
   animated?: boolean;
   areas: AreaGeometry[];
   num?: number;
   style: AreaSeriesStyle;
+  sharedStyle: SharedGeometryStyle;
   onElementClick?: ElementClickListener;
   onElementOver: ((tooltip: TooltipData) => void) & IAction;
   onElementOut: (() => void) & IAction;
@@ -24,7 +30,7 @@ interface AreaGeometriesDataState {
 export class AreaGeometries extends React.PureComponent<
   AreaGeometriesDataProps,
   AreaGeometriesDataState
-  > {
+> {
   static defaultProps: Partial<AreaGeometriesDataProps> = {
     animated: false,
     num: 1,
@@ -86,45 +92,45 @@ export class AreaGeometries extends React.PureComponent<
       [] as JSX.Element[],
     );
   }
-  private renderPoints = (points: PointGeometry[], i: number): JSX.Element[] => {
-    const { style } = this.props;
+  private renderPoints = (areaPoints: PointGeometry[], i: number): JSX.Element[] => {
+    const { radius, stroke, strokeWidth } = this.props.style.point;
     const { overPoint } = this.state;
 
-    return points.map((point, index) => {
-      const { x, y, color, value, transform } = point;
+    return areaPoints.map((areaPoint, index) => {
+      const { x, y, color, value, transform } = areaPoint;
       return (
         <Group key={`point-${i}-${index}`}>
           <Circle
             x={transform.x + x}
             y={y}
-            radius={style.dataPointsRadius * 2.5}
+            radius={radius * 2.5}
             onClick={this.onElementClick(value)}
-            onMouseOver={this.onOverPoint(point)}
+            onMouseOver={this.onOverPoint(areaPoint)}
             onMouseLeave={this.onOutPoint}
             fill={'gray'}
-            opacity={overPoint === point ? 0.3 : 0}
+            opacity={overPoint === areaPoint ? 0.3 : 0}
           />
           <Circle
             x={transform.x + x}
             y={y}
-            radius={style.dataPointsRadius}
+            radius={radius}
             strokeWidth={0}
             fill={color}
-            opacity={overPoint === point ? 0.5 : 0}
+            opacity={overPoint === areaPoint ? 0.5 : 0}
             strokeHitEnabled={false}
             listening={false}
             perfectDrawEnabled={true}
           />
           <Circle
             x={transform.x + x}
             y={y}
-            radius={style.dataPointsRadius}
-            onMouseOver={this.onOverPoint(point)}
+            radius={radius}
+            onMouseOver={this.onOverPoint(areaPoint)}
             onMouseLeave={this.onOutPoint}
             fill={'transparent'}
-            stroke={style.dataPointsStroke}
-            strokeWidth={style.dataPointsStrokeWidth}
-            opacity={overPoint === point ? 1 : 0}
+            stroke={stroke}
+            strokeWidth={strokeWidth}
+            opacity={overPoint === areaPoint ? 1 : 0}
             strokeHitEnabled={false}
             listening={false}
             perfectDrawEnabled={true}
@@ -135,11 +141,15 @@ export class AreaGeometries extends React.PureComponent<
   }
 
   private renderAreaGeoms = (): JSX.Element[] => {
-    const { areas } = this.props;
+    const { areas, sharedStyle } = this.props;
     return areas.map((glyph, i) => {
       const { area, color, transform, geometryId } = glyph;
 
-      const geometryStyle = getGeometryStyle(geometryId, this.props.highlightedLegendItem);
+      const geometryStyle = getGeometryStyle(
+        geometryId,
+        this.props.highlightedLegendItem,
+        sharedStyle,
+      );
 
       if (this.props.animated) {
         return (
@@ -152,24 +162,14 @@ export class AreaGeometries extends React.PureComponent<
                   fill={color}
                   listening={false}
                   {...geometryStyle}
-                // areaCap="round"
-                // areaJoin="round"
                 />
               )}
             </Spring>
           </Group>
         );
       } else {
         return (
-          <Path
-            key={`area-${i}`}
-            data={area}
-            fill={color}
-            listening={false}
-            {...geometryStyle}
-          // areaCap="round"
-          // areaJoin="round"
-          />
+          <Path key={`area-${i}`} data={area} fill={color} listening={false} {...geometryStyle} />
         );
       }
     });