Switch ANSI rendering to termenv to automatically convert colors between color-profiles

ansi/style.go

@@ -1,9 +1,5 @@
 package ansi
 
-import (
-	"github.com/lucasb-eyer/go-colorful"
-)
-
 // Chroma holds all the chroma settings.
 type Chroma struct {
 	Text                StylePrimitive `json:"text,omitempty"`
@@ -229,53 +225,3 @@ func cascadeStyle(parent StyleBlock, child StyleBlock, toBlock bool) StyleBlock
 
 	return s
 }
-
-func hexToANSIColor(h string) (int, error) {
-	c, err := colorful.Hex(h)
-	if err != nil {
-		return 0, err
-	}
-
-	v2ci := func(v float64) int {
-		if v < 48 {
-			return 0
-		}
-		if v < 115 {
-			return 1
-		}
-		return int((v - 35) / 40)
-	}
-
-	// Calculate the nearest 0-based color index at 16..231
-	r := v2ci(c.R * 255.0) // 0..5 each
-	g := v2ci(c.G * 255.0)
-	b := v2ci(c.B * 255.0)
-	ci := 36*r + 6*g + b /* 0..215 */
-
-	// Calculate the represented colors back from the index
-	i2cv := [6]int{0, 0x5f, 0x87, 0xaf, 0xd7, 0xff}
-	cr := i2cv[r] // r/g/b, 0..255 each
-	cg := i2cv[g]
-	cb := i2cv[b]
-
-	// Calculate the nearest 0-based gray index at 232..255
-	var grayIdx int
-	average := (r + g + b) / 3
-	if average > 238 {
-		grayIdx = 23
-	} else {
-		grayIdx = (average - 3) / 10 // 0..23
-	}
-	gv := 8 + 10*grayIdx // same value for r/g/b, 0..255
-
-	// Return the one which is nearer to the original input rgb value
-	c2 := colorful.Color{R: float64(cr) / 255.0, G: float64(cg) / 255.0, B: float64(cb) / 255.0}
-	g2 := colorful.Color{R: float64(gv) / 255.0, G: float64(gv) / 255.0, B: float64(gv) / 255.0}
-	colorDist := c.DistanceLab(c2)
-	grayDist := c.DistanceLab(g2)
-
-	if colorDist <= grayDist {
-		return 16 + ci, nil
-	}
-	return 232 + grayIdx, nil
-}