refactor: split casino.go, dedup helpers, remove audit docs

1 files changed, 19 insertions, 2 deletions

diff --git a/internal/color/color.go b/internal/color/color.go
index ff47a47..8376dde 100644
--- a/internal/color/color.go
+++ b/internal/color/color.go
@@ -36,7 +36,18 @@ var ansi16RGB = [16][3]int{
 
 var cubeValues = [6]int{0, 95, 135, 175, 215, 255}
 
+// Plain reports whether a color mode renders no color. The empty mode and
+// "none" are equivalent (Render treats both as plain), so callers should use
+// this instead of open-coding the pair.
+func Plain(mode string) bool { return mode == "" || mode == "none" }
+
 func Xterm256ToRGB(index int) (int, int, int) {
+	if index < 0 {
+		index = 0
+	}
+	if index > 255 {
+		index = 255
+	}
 	if index < 16 {
 		return ansi16RGB[index][0], ansi16RGB[index][1], ansi16RGB[index][2]
 	}
@@ -205,8 +216,14 @@ func TruncateVisible(s string, maxVisible int, unicode bool) string {
 	}
 	var pre, suf string
 	rest := s
-	if idx := strings.IndexByte(rest, 'm'); idx >= 0 && strings.HasPrefix(rest, "\x1b[") {
-		pre = rest[:idx+1]
+	// Render emits style and foreground as separate SGR sequences; peel every
+	// leading one, not just the first, or the second is counted as visible text.
+	for strings.HasPrefix(rest, "\x1b[") {
+		idx := strings.IndexByte(rest, 'm')
+		if idx < 0 {
+			break
+		}
+		pre += rest[:idx+1]
 		rest = rest[idx+1:]
 	}
 	if strings.HasSuffix(rest, Reset) {