From 5d47b170b42868cbd9ca40ae4e5aea7522ea3cfd Mon Sep 17 00:00:00 2001
From: Irina Kuzmina <kuzmadom@yandex-team.ru>
Date: Thu, 5 Dec 2024 12:47:17 +0300
Subject: [PATCH] feat: add legend title alignment option (#17)

---
 .../__data__/pie/continuous-legend.ts         | 18 +++++------
 src/components/Legend/index.tsx               | 30 +++++++++++++++----
 src/hooks/useSeries/prepare-legend.ts         |  1 +
 src/hooks/useSeries/types.ts                  |  1 +
 src/types/chart/legend.ts                     |  2 ++
 5 files changed, 37 insertions(+), 15 deletions(-)

diff --git a/src/__stories__/__data__/pie/continuous-legend.ts b/src/__stories__/__data__/pie/continuous-legend.ts
index 2e2059f..58145dc 100644
--- a/src/__stories__/__data__/pie/continuous-legend.ts
+++ b/src/__stories__/__data__/pie/continuous-legend.ts
@@ -1,22 +1,20 @@
-import {groups} from 'd3';
-
+import {formatNumber} from '../../../libs';
 import type {ChartData, PieSeriesData} from '../../../types';
 import {getContinuesColorFn} from '../../../utils';
-import nintendoGames from '../nintendoGames';
 
 function prepareData(): ChartData {
     const colors = ['rgb(255, 61, 100)', 'rgb(255, 198, 54)', 'rgb(84, 165, 32)'];
     const stops = [0, 0.5, 1];
 
-    const gamesByPlatform = groups(nintendoGames, (item) => item.platform);
-    const data: PieSeriesData[] = gamesByPlatform.map(([platform, games]) => ({
-        name: platform,
-        value: games.length,
-        label: `${platform}(${games.length})`,
-    }));
+    const data: PieSeriesData[] = [
+        {name: 'A', value: 1200000},
+        {name: 'B', value: 900000},
+        {name: 'C', value: 1310000},
+    ];
     const getColor = getContinuesColorFn({colors, stops, values: data.map((d) => d.value)});
     data.forEach((d) => {
         d.color = getColor(d.value);
+        d.label = formatNumber(d.value, {unit: 'auto'});
     });
 
     return {
@@ -32,7 +30,7 @@ function prepareData(): ChartData {
         legend: {
             enabled: true,
             type: 'continuous',
-            title: {text: 'Games by platform'},
+            title: {text: 'Legend for continues color'},
             colorScale: {
                 colors: colors,
                 stops,
diff --git a/src/components/Legend/index.tsx b/src/components/Legend/index.tsx
index 0aedc95..0d5a97d 100644
--- a/src/components/Legend/index.tsx
+++ b/src/components/Legend/index.tsx
@@ -13,6 +13,7 @@ import type {
     SymbolLegendSymbol,
 } from '../../hooks';
 import {getLineDashArray} from '../../hooks/useShapes/utils';
+import {formatNumber} from '../../libs';
 import {
     block,
     createGradientRect,
@@ -39,9 +40,9 @@ const getLegendPosition = (args: {
     align: PreparedLegend['align'];
     contentWidth: number;
     width: number;
-    offsetWidth: number;
+    offsetWidth?: number;
 }) => {
-    const {align, offsetWidth, width, contentWidth} = args;
+    const {align, offsetWidth = 0, width, contentWidth} = args;
     const top = 0;
 
     if (align === 'left') {
@@ -311,14 +312,16 @@ export const Legend = (props: Props) => {
             });
 
             // ticks
+            const scale = scaleLinear(domain, [0, legend.width]) as AxisScale<AxisDomain>;
             const xAxisGenerator = axisBottom({
-                scale: scaleLinear(domain, [0, legend.width]) as AxisScale<AxisDomain>,
+                scale,
                 ticks: {
                     items: [[0, -rectHeight]],
                     labelsMargin: legend.ticks.labelsMargin,
                     labelsLineHeight: legend.ticks.labelsLineHeight,
                     maxTickCount: 4,
                     tickColor: '#fff',
+                    labelFormat: (value: number) => formatNumber(value, {unit: 'auto'}),
                 },
                 domain: {
                     size: legend.width,
@@ -334,15 +337,32 @@ export const Legend = (props: Props) => {
         }
 
         if (legend.title.enable) {
-            const {maxWidth: labelWidth} = getLabelsSize({
+            const {maxWidth: titleWidth} = getLabelsSize({
                 labels: [legend.title.text],
                 style: legend.title.style,
             });
+            let dx = 0;
+            switch (legend.title.align) {
+                case 'center': {
+                    dx = legend.width / 2 - titleWidth / 2;
+                    break;
+                }
+                case 'right': {
+                    dx = legend.width - titleWidth;
+                    break;
+                }
+                case 'left':
+                default: {
+                    dx = 0;
+                    break;
+                }
+            }
+
             svgElement
                 .append('g')
                 .attr('class', b('title'))
                 .append('text')
-                .attr('dx', legend.width / 2 - labelWidth / 2)
+                .attr('dx', dx)
                 .attr('font-weight', legend.title.style.fontWeight ?? null)
                 .attr('font-size', legend.title.style.fontSize ?? null)
                 .attr('fill', legend.title.style.fontColor ?? null)
diff --git a/src/hooks/useSeries/prepare-legend.ts b/src/hooks/useSeries/prepare-legend.ts
index b07fa11..ff9e761 100644
--- a/src/hooks/useSeries/prepare-legend.ts
+++ b/src/hooks/useSeries/prepare-legend.ts
@@ -90,6 +90,7 @@ export const getPreparedLegend = (args: {
             margin: titleMargin,
             style: titleStyle,
             height: titleHeight,
+            align: get(legend, 'title.align', 'left'),
         },
         width: legendWidth,
         ticks,
diff --git a/src/hooks/useSeries/types.ts b/src/hooks/useSeries/types.ts
index 0920e8b..23fbc9b 100644
--- a/src/hooks/useSeries/types.ts
+++ b/src/hooks/useSeries/types.ts
@@ -56,6 +56,7 @@ export type PreparedLegend = Required<Omit<ChartLegend, 'title' | 'colorScale'>>
         margin: number;
         style: BaseTextStyle;
         height: number;
+        align: Required<Required<ChartLegend>['title']>['align'];
     };
     ticks: {
         labelsMargin: number;
diff --git a/src/types/chart/legend.ts b/src/types/chart/legend.ts
index 957428b..d52c404 100644
--- a/src/types/chart/legend.ts
+++ b/src/types/chart/legend.ts
@@ -41,6 +41,8 @@ export type ChartLegend = {
          * Defaults to 4 for horizontal axes, 8 for vertical.
          * */
         margin?: number;
+        /** The horizontal alignment of the title. */
+        align?: 'left' | 'center' | 'right';
     };
     /* Gradient color settings for continuous legend type */
     colorScale?: {