1 files changed, 129 insertions, 5 deletions

diff --git a/packages/tui/internal/theme/manager.go b/packages/tui/internal/theme/manager.go
index 87fbc131d..583e8c491 100644
--- a/packages/tui/internal/theme/manager.go
+++ b/packages/tui/internal/theme/manager.go
@@ -2,19 +2,25 @@ package theme
 
 import (
 	"fmt"
+	"image/color"
 	"slices"
+	"strconv"
 	"strings"
 	"sync"
 
 	"github.com/alecthomas/chroma/v2/styles"
+	"github.com/charmbracelet/lipgloss/v2"
+	"github.com/charmbracelet/lipgloss/v2/compat"
+	"github.com/charmbracelet/x/ansi"
 )
 
 // Manager handles theme registration, selection, and retrieval.
 // It maintains a registry of available themes and tracks the currently active theme.
 type Manager struct {
-	themes      map[string]Theme
-	currentName string
-	mu          sync.RWMutex
+	themes               map[string]Theme
+	currentName          string
+	currentUsesAnsiCache bool // Cache whether current theme uses ANSI colors
+	mu                   sync.RWMutex
 }
 
 // Global instance of the theme manager
@@ -34,6 +40,7 @@ func RegisterTheme(name string, theme Theme) {
 	// If this is the first theme, make it the default
 	if globalManager.currentName == "" {
 		globalManager.currentName = name
+		globalManager.currentUsesAnsiCache = themeUsesAnsiColors(theme)
 	}
 }
 
@@ -44,11 +51,13 @@ func SetTheme(name string) error {
 	defer globalManager.mu.Unlock()
 	delete(styles.Registry, "charm")
 
-	if _, exists := globalManager.themes[name]; !exists {
+	theme, exists := globalManager.themes[name]
+	if !exists {
 		return fmt.Errorf("theme '%s' not found", name)
 	}
 
 	globalManager.currentName = name
+	globalManager.currentUsesAnsiCache = themeUsesAnsiColors(theme)
 
 	return nil
 }
@@ -84,7 +93,11 @@ func AvailableThemes() []string {
 		names = append(names, name)
 	}
 	slices.SortFunc(names, func(a, b string) int {
-		// list system theme first
+		if a == "system" {
+			return -1
+		} else if b == "system" {
+			return 1
+		}
 		if a == "opencode" {
 			return -1
 		} else if b == "opencode" {
@@ -103,3 +116,114 @@ func GetTheme(name string) Theme {
 
 	return globalManager.themes[name]
 }
+
+// UpdateSystemTheme updates the system theme with terminal background info
+func UpdateSystemTheme(terminalBg color.Color, isDark bool) {
+	globalManager.mu.Lock()
+	defer globalManager.mu.Unlock()
+
+	dynamicTheme := NewSystemTheme(terminalBg, isDark)
+	globalManager.themes["system"] = dynamicTheme
+	if globalManager.currentName == "system" {
+		globalManager.currentUsesAnsiCache = themeUsesAnsiColors(dynamicTheme)
+	}
+}
+
+// CurrentThemeUsesAnsiColors returns true if the current theme uses ANSI 0-16 colors
+func CurrentThemeUsesAnsiColors() bool {
+	// globalManager.mu.RLock()
+	// defer globalManager.mu.RUnlock()
+
+	return globalManager.currentUsesAnsiCache
+}
+
+// isAnsiColor checks if a color represents an ANSI 0-16 color
+func isAnsiColor(c color.Color) bool {
+	if _, ok := c.(lipgloss.NoColor); ok {
+		return false
+	}
+	if _, ok := c.(ansi.BasicColor); ok {
+		return true
+	}
+
+	// For other color types, check if they represent ANSI colors
+	// by examining their string representation
+	if stringer, ok := c.(fmt.Stringer); ok {
+		str := stringer.String()
+		// Check if it's a numeric ANSI color (0-15)
+		if num, err := strconv.Atoi(str); err == nil && num >= 0 && num <= 15 {
+			return true
+		}
+	}
+
+	return false
+}
+
+// adaptiveColorUsesAnsi checks if an AdaptiveColor uses ANSI colors
+func adaptiveColorUsesAnsi(ac compat.AdaptiveColor) bool {
+	if isAnsiColor(ac.Dark) {
+		return true
+	}
+	if isAnsiColor(ac.Light) {
+		return true
+	}
+	return false
+}
+
+// themeUsesAnsiColors checks if a theme uses any ANSI 0-16 colors
+func themeUsesAnsiColors(theme Theme) bool {
+	if theme == nil {
+		return false
+	}
+
+	return adaptiveColorUsesAnsi(theme.Primary()) ||
+		adaptiveColorUsesAnsi(theme.Secondary()) ||
+		adaptiveColorUsesAnsi(theme.Accent()) ||
+		adaptiveColorUsesAnsi(theme.Error()) ||
+		adaptiveColorUsesAnsi(theme.Warning()) ||
+		adaptiveColorUsesAnsi(theme.Success()) ||
+		adaptiveColorUsesAnsi(theme.Info()) ||
+		adaptiveColorUsesAnsi(theme.Text()) ||
+		adaptiveColorUsesAnsi(theme.TextMuted()) ||
+		adaptiveColorUsesAnsi(theme.Background()) ||
+		adaptiveColorUsesAnsi(theme.BackgroundPanel()) ||
+		adaptiveColorUsesAnsi(theme.BackgroundElement()) ||
+		adaptiveColorUsesAnsi(theme.Border()) ||
+		adaptiveColorUsesAnsi(theme.BorderActive()) ||
+		adaptiveColorUsesAnsi(theme.BorderSubtle()) ||
+		adaptiveColorUsesAnsi(theme.DiffAdded()) ||
+		adaptiveColorUsesAnsi(theme.DiffRemoved()) ||
+		adaptiveColorUsesAnsi(theme.DiffContext()) ||
+		adaptiveColorUsesAnsi(theme.DiffHunkHeader()) ||
+		adaptiveColorUsesAnsi(theme.DiffHighlightAdded()) ||
+		adaptiveColorUsesAnsi(theme.DiffHighlightRemoved()) ||
+		adaptiveColorUsesAnsi(theme.DiffAddedBg()) ||
+		adaptiveColorUsesAnsi(theme.DiffRemovedBg()) ||
+		adaptiveColorUsesAnsi(theme.DiffContextBg()) ||
+		adaptiveColorUsesAnsi(theme.DiffLineNumber()) ||
+		adaptiveColorUsesAnsi(theme.DiffAddedLineNumberBg()) ||
+		adaptiveColorUsesAnsi(theme.DiffRemovedLineNumberBg()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownText()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownHeading()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownLink()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownLinkText()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownCode()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownBlockQuote()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownEmph()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownStrong()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownHorizontalRule()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownListItem()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownListEnumeration()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownImage()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownImageText()) ||
+		adaptiveColorUsesAnsi(theme.MarkdownCodeBlock()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxComment()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxKeyword()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxFunction()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxVariable()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxString()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxNumber()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxType()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxOperator()) ||
+		adaptiveColorUsesAnsi(theme.SyntaxPunctuation())
+}