Merge branch 'johan/ui-colors-from-chroma'

m/styling.go

@@ -55,6 +55,42 @@ func twinStyleFromChroma(chromaStyle *chroma.Style, chromaFormatter *chroma.Form
 	return &cells[0].Style
 }
 
+func backgroundStyleFromChroma(chromaStyle chroma.Style) twin.Style {
+	backgroundEntry := chromaStyle.Get(chroma.Background)
+
+	backgroundColor := twin.ColorDefault
+	if backgroundEntry.Background.IsSet() {
+		backgroundColor = twin.NewColor24Bit(
+			backgroundEntry.Background.Red(),
+			backgroundEntry.Background.Green(),
+			backgroundEntry.Background.Blue())
+	}
+
+	foregroundColor := twin.ColorDefault
+	if backgroundEntry.Colour.IsSet() {
+		foregroundColor = twin.NewColor24Bit(
+			backgroundEntry.Colour.Red(),
+			backgroundEntry.Colour.Green(),
+			backgroundEntry.Colour.Blue())
+	}
+
+	returnMe := twin.StyleDefault.
+		WithBackground(backgroundColor).
+		WithForeground(foregroundColor)
+
+	if backgroundEntry.Bold == chroma.Yes {
+		returnMe = returnMe.WithAttr(twin.AttrBold)
+	}
+	if backgroundEntry.Italic == chroma.Yes {
+		returnMe = returnMe.WithAttr(twin.AttrItalic)
+	}
+	if backgroundEntry.Underline == chroma.Yes {
+		returnMe = returnMe.WithAttr(twin.AttrUnderline)
+	}
+
+	return returnMe
+}
+
 // consumeLessTermcapEnvs parses LESS_TERMCAP_xx environment variables and
 // adapts the moar output accordingly.
 func consumeLessTermcapEnvs(chromaStyle *chroma.Style, chromaFormatter *chroma.Formatter) {
@@ -88,8 +124,11 @@ func styleUi(chromaStyle *chroma.Style, chromaFormatter *chroma.Formatter, statu
 	if standoutStyle != nil {
 		statusbarStyle = *standoutStyle
 	} else if statusbarOption == STATUSBAR_STYLE_INVERSE {
-		// FIXME: Get this from the Chroma style
+		if chromaStyle != nil {
+			statusbarStyle = backgroundStyleFromChroma(*chromaStyle).WithAttr(twin.AttrReverse)
+		} else {
 			statusbarStyle = twin.StyleDefault.WithAttr(twin.AttrReverse)
+		}
 	} else if statusbarOption == STATUSBAR_STYLE_PLAIN {
 		plain := twinStyleFromChroma(chromaStyle, chromaFormatter, chroma.None)
 		if plain != nil {

m/styling_test.go

@@ -0,0 +1,54 @@
+package m
+
+import (
+	"testing"
+
+	"github.com/alecthomas/chroma/v2/styles"
+	"github.com/walles/moar/twin"
+	"gotest.tools/v3/assert"
+)
+
+func TestBackgroundStyleFromChromaGithub(t *testing.T) {
+	style := backgroundStyleFromChroma(*styles.Get("github"))
+
+	assert.Equal(t, style.String(), "Default color on #ffffff")
+}
+
+func TestBackgroundStyleFromChromaAverage(t *testing.T) {
+	// Verify we get the right values out of a style with both Text and Background.
+	style := backgroundStyleFromChroma(*styles.Get("average"))
+	assert.Equal(t, style.String(), "#757575 on #000000")
+}
+
+func TestBackgroundStyleFromChromaNative(t *testing.T) {
+	// Verify we get the right values out of a style where Background comes with
+	// both foreground and background.
+	style := backgroundStyleFromChroma(*styles.Get("native"))
+	assert.Equal(t, style.String(), "#d0d0d0 on #202020")
+}
+
+// Loop over all styles and check that the contrast we get in
+// backgroundStyleFromChroma is good enough.
+func TestBackgroundStyleContrast(t *testing.T) {
+	for _, style := range styles.Registry {
+		t.Run(style.Name, func(t *testing.T) {
+			backgroundStyle := backgroundStyleFromChroma(*style)
+
+			if backgroundStyle.Foreground().ColorType() == twin.ColorTypeDefault {
+				return
+			}
+
+			if backgroundStyle.Background().ColorType() == twin.ColorTypeDefault {
+				return
+			}
+
+			distance := backgroundStyle.Background().Distance(backgroundStyle.Foreground())
+
+			// 0.4 feels low, but as of Chroma v2.12.0 this is the distance we
+			// get for some styles (solarized-dark, solarized-light, average).
+			//
+			// Let's at least verify it doesn't get worse than this.
+			assert.Check(t, distance > 0.4, "distance=%f", distance)
+		})
+	}
+}

twin/styles.go

@@ -117,6 +117,14 @@ func (attr AttrMask) has(attrs AttrMask) bool {
 	return attr&attrs != 0
 }
 
+func (style Style) Background() Color {
+	return style.bg
+}
+
+func (style Style) Foreground() Color {
+	return style.fg
+}
+
 func (style Style) WithBackground(color Color) Style {
 	return Style{
 		fg:           style.fg,