1 files changed, 103 insertions, 0 deletions
diff --git a/internal/tui/theme.go b/internal/tui/theme.go
new file mode 100644
index 0000000..862f193
--- /dev/null
+++ b/internal/tui/theme.go
@@ -0,0 +1,103 @@
+package tui
+
+import (
+	"math/rand/v2"
+	"strconv"
+)
+
+// Theme defines the shared color palette used across the TUI.
+type Theme struct {
+	HeaderFG   string
+	SelectedFG string
+	SelectedBG string
+	RowFG      string
+	RowBG      string
+	StatusFG   string
+	StatusBG   string
+	SearchFG   string
+	SearchBG   string
+}
+
+// DefaultTheme returns the baseline theme inspired by Task Samurai.
+func DefaultTheme() Theme {
+	return Theme{
+		HeaderFG:   "205",
+		SelectedFG: "229",
+		SelectedBG: "57",
+		RowFG:      "15",
+		RowBG:      "236",
+		StatusFG:   "229",
+		StatusBG:   "57",
+		SearchFG:   "21",
+		SearchBG:   "226",
+	}
+}
+
+// RandomTheme returns a randomized high-contrast palette for disco mode.
+func RandomTheme() Theme {
+	theme := Theme{
+		HeaderFG:   randomColor(),
+		SelectedBG: randomColor(),
+		RowBG:      randomColor(),
+		StatusBG:   randomColor(),
+		SearchBG:   randomColor(),
+	}
+
+	theme.SelectedFG = contrastColor(theme.SelectedBG)
+	theme.RowFG = contrastColor(theme.RowBG)
+	theme.StatusFG = contrastColor(theme.StatusBG)
+	theme.SearchFG = contrastColor(theme.SearchBG)
+	return theme
+}
+
+func randomColor() string {
+	return strconv.Itoa(rand.IntN(256))
+}
+
+func contrastColor(background string) string {
+	value, err := strconv.Atoi(background)
+	if err != nil {
+		return "15"
+	}
+
+	if xtermBrightness(value) > 128 {
+		return "0"
+	}
+	return "15"
+}
+
+func xtermBrightness(index int) float64 {
+	red, green, blue := xtermRGB(index)
+	return 0.299*float64(red) + 0.587*float64(green) + 0.114*float64(blue)
+}
+
+func xtermRGB(index int) (int, int, int) {
+	if index < 0 {
+		index = 0
+	}
+	if index > 255 {
+		index = 255
+	}
+
+	if index < 16 {
+		table := [16][3]int{
+			{0, 0, 0}, {205, 0, 0}, {0, 205, 0}, {205, 205, 0},
+			{0, 0, 238}, {205, 0, 205}, {0, 205, 205}, {229, 229, 229},
+			{127, 127, 127}, {255, 0, 0}, {0, 255, 0}, {255, 255, 0},
+			{92, 92, 255}, {255, 0, 255}, {0, 255, 255}, {255, 255, 255},
+		}
+		rgb := table[index]
+		return rgb[0], rgb[1], rgb[2]
+	}
+
+	if index <= 231 {
+		index -= 16
+		red := (index / 36) * 51
+		green := (index % 36 / 6) * 51
+		blue := (index % 6) * 51
+		return red, green, blue
+	}
+
+	gray := (index-232)*10 + 8
+	return gray, gray, gray
+}