refactor: enhance painter

theme.go

@@ -22,13 +22,20 @@
 
 package charts
 
+import "github.com/wcharczuk/go-chart/v2/drawing"
+
 const ThemeDark = "dark"
 const ThemeLight = "light"
 const ThemeGrafana = "grafana"
 const ThemeAnt = "ant"
 
-type Theme struct {
-	palette *themeColorPalette
+type ColorPalette interface {
+	IsDark() bool
+	GetAxisStrokeColor() Color
+	GetAxisSplitLineColor() Color
+	GetSeriesColor(int) Color
+	GetBackgroundColor() Color
+	GetTextColor() Color
 }
 
 type themeColorPalette struct {
@@ -39,3 +46,190 @@ type themeColorPalette struct {
 	textColor          Color
 	seriesColors       []Color
 }
+
+var palettes = map[string]ColorPalette{}
+
+func init() {
+	echartSeriesColors := []Color{
+		parseColor("#5470c6"),
+		parseColor("#91cc75"),
+		parseColor("#fac858"),
+		parseColor("#ee6666"),
+		parseColor("#73c0de"),
+		parseColor("#3ba272"),
+		parseColor("#fc8452"),
+		parseColor("#9a60b4"),
+		parseColor("#ea7ccc"),
+	}
+	grafanaSeriesColors := []Color{
+		parseColor("#7EB26D"),
+		parseColor("#EAB839"),
+		parseColor("#6ED0E0"),
+		parseColor("#EF843C"),
+		parseColor("#E24D42"),
+		parseColor("#1F78C1"),
+		parseColor("#705DA0"),
+		parseColor("#508642"),
+	}
+	antSeriesColors := []Color{
+		parseColor("#5b8ff9"),
+		parseColor("#5ad8a6"),
+		parseColor("#5d7092"),
+		parseColor("#f6bd16"),
+		parseColor("#6f5ef9"),
+		parseColor("#6dc8ec"),
+		parseColor("#945fb9"),
+		parseColor("#ff9845"),
+	}
+	AddTheme(
+		ThemeDark,
+		true,
+		Color{
+			R: 185,
+			G: 184,
+			B: 206,
+			A: 255,
+		},
+		Color{
+			R: 72,
+			G: 71,
+			B: 83,
+			A: 255,
+		},
+		Color{
+			R: 16,
+			G: 12,
+			B: 42,
+			A: 255,
+		},
+		Color{
+			R: 238,
+			G: 238,
+			B: 238,
+			A: 255,
+		},
+		echartSeriesColors,
+	)
+
+	AddTheme(
+		ThemeLight,
+		false,
+		Color{
+			R: 110,
+			G: 112,
+			B: 121,
+			A: 255,
+		},
+		Color{
+			R: 224,
+			G: 230,
+			B: 242,
+			A: 255,
+		},
+		drawing.ColorWhite,
+		drawing.Color{
+			R: 70,
+			G: 70,
+			B: 70,
+			A: 255,
+		},
+		echartSeriesColors,
+	)
+	AddTheme(
+		ThemeAnt,
+		false,
+		Color{
+			R: 110,
+			G: 112,
+			B: 121,
+			A: 255,
+		},
+		Color{
+			R: 224,
+			G: 230,
+			B: 242,
+			A: 255,
+		},
+		drawing.ColorWhite,
+		drawing.Color{
+			R: 70,
+			G: 70,
+			B: 70,
+			A: 255,
+		},
+		antSeriesColors,
+	)
+	AddTheme(
+		ThemeGrafana,
+		true,
+		drawing.Color{
+			R: 185,
+			G: 184,
+			B: 206,
+			A: 255,
+		},
+		drawing.Color{
+			R: 68,
+			G: 67,
+			B: 67,
+			A: 255,
+		},
+		drawing.Color{
+			R: 31,
+			G: 29,
+			B: 29,
+			A: 255,
+		},
+		drawing.Color{
+			R: 216,
+			G: 217,
+			B: 218,
+			A: 255,
+		},
+		grafanaSeriesColors,
+	)
+}
+
+func AddTheme(name string, isDarkMode bool, axisStrokeColor, axisSplitLineColor, backgroundColor, textColor drawing.Color, seriesColors []drawing.Color) {
+	palettes[name] = &themeColorPalette{
+		isDarkMode:         isDarkMode,
+		axisStrokeColor:    axisStrokeColor,
+		axisSplitLineColor: axisSplitLineColor,
+		backgroundColor:    backgroundColor,
+		textColor:          textColor,
+		seriesColors:       seriesColors,
+	}
+}
+
+func NewTheme(name string) ColorPalette {
+	p, ok := palettes[name]
+	if !ok {
+		p = palettes[ThemeLight]
+	}
+	return p
+}
+
+func (t *themeColorPalette) IsDark() bool {
+	return t.isDarkMode
+}
+
+func (t *themeColorPalette) GetAxisStrokeColor() Color {
+	return t.axisStrokeColor
+}
+
+func (t *themeColorPalette) GetAxisSplitLineColor() Color {
+	return t.axisSplitLineColor
+}
+
+func (t *themeColorPalette) GetSeriesColor(index int) Color {
+	colors := t.seriesColors
+	return colors[index%len(colors)]
+}
+
+func (t *themeColorPalette) GetBackgroundColor() Color {
+	return t.backgroundColor
+}
+
+func (t *themeColorPalette) GetTextColor() Color {
+	return t.textColor
+}