feat(ui): implement adaptive system theme preferences with live AppKi…

internal/config/config.go

@@ -37,6 +37,7 @@ func DefaultConfig() Config {
 			HighCPUThreshold:        75,
 			HighCPUDuration:         30 * time.Second,
 			HighCPUCooldown:         10 * time.Minute,
+			Theme:                   "system", // 👈 Default fallback for new installations
 		},
 		Rules: make([]core.AppRule, 0),
 	}
@@ -62,6 +63,10 @@ func MigrateConfig(in Config) (Config, error) {
 	in.Preferences.TopProcessesSort = core.NormalizeTopProcessesSortMode(in.Preferences.TopProcessesSort)
 	in.Preferences.CPUDisplayMode = core.NormalizeCPUDisplayMode(in.Preferences.CPUDisplayMode)
 	in.Preferences.CPUGraphWindow = core.NormalizeCPUGraphWindow(in.Preferences.CPUGraphWindow)
+
+	// 👈 Clean up and normalize the theme input text
+	in.Preferences.Theme = core.NormalizeThemeMode(in.Preferences.Theme)
+
 	if in.Preferences.HighCPUThreshold == 0 {
 		in.Preferences.HighCPUThreshold = defaults.Preferences.HighCPUThreshold
 	}
@@ -149,6 +154,13 @@ func (store Store) LoadConfig() (Config, error) {
 		migrated.Preferences.CPUGraphWindow = DefaultConfig().Preferences.CPUGraphWindow
 		changed = true
 	}
+
+	// 👈 Backfill legacy installations that don't have a theme selected yet
+	if !configHasPreference(payload, "theme") {
+		migrated.Preferences.Theme = DefaultConfig().Preferences.Theme
+		changed = true
+	}
+
 	if !configHasPreference(payload, "wakeGrace") {
 		migrated.Preferences.WakeGrace = DefaultConfig().Preferences.WakeGrace
 		if hasLegacyStartupGrace {

internal/config/config_test.go

@@ -39,6 +39,9 @@ func TestLoadConfigReturnsDefaultsWhenMissing(t *testing.T) {
 	if cfg.Preferences.CPUDisplayMode != core.CPUDisplayModePerCoreProcess {
 		t.Fatalf("CPU display mode = %q, want %q", cfg.Preferences.CPUDisplayMode, core.CPUDisplayModePerCoreProcess)
 	}
+	if cfg.Preferences.Theme != "system" {
+		t.Fatalf("theme = %q, want %q", cfg.Preferences.Theme, "system")
+	}
 }
 
 func TestSaveConfigWritesAtomicallyReadableConfig(t *testing.T) {
@@ -148,7 +151,6 @@ func TestLoadConfigBackfillsMissingPreferences(t *testing.T) {
 	if err := os.WriteFile(filepath.Join(dir, "config.json"), payload, 0o644); err != nil {
 		t.Fatalf("write config: %v", err)
 	}
-
 	cfg, err := store.LoadConfig()
 	if err != nil {
 		t.Fatalf("load: %v", err)
@@ -171,6 +173,9 @@ func TestLoadConfigBackfillsMissingPreferences(t *testing.T) {
 	if cfg.Preferences.CPUDisplayMode != core.CPUDisplayModePerCoreProcess {
 		t.Fatalf("CPU display mode = %q, want %q", cfg.Preferences.CPUDisplayMode, core.CPUDisplayModePerCoreProcess)
 	}
+	if cfg.Preferences.Theme != "system" {
+		t.Fatal("theme should be backfilled to system")
+	}
 	updated, err := os.ReadFile(filepath.Join(dir, "config.json"))
 	if err != nil {
 		t.Fatalf("read updated config: %v", err)
@@ -193,6 +198,9 @@ func TestLoadConfigBackfillsMissingPreferences(t *testing.T) {
 	if !bytes.Contains(updated, []byte(`"cpuDisplayMode": "per_core_process"`)) {
 		t.Fatalf("updated config missing cpuDisplayMode: %s", updated)
 	}
+	if !bytes.Contains(updated, []byte(`"theme": "system"`)) {
+		t.Fatalf("updated config missing theme: %s", updated)
+	}
 	if bytes.Contains(updated, []byte("startupGrace")) {
 		t.Fatalf("updated config should drop legacy startupGrace: %s", updated)
 	}

internal/core/rules.go

@@ -1,8 +1,9 @@
 package core
 
-import "slices"
-
-import "time"
+import (
+	"slices"
+	"time"
+)
 
 type RuleMode string
 type RuleTrackingLocation string
@@ -141,6 +142,7 @@ type GlobalPreferences struct {
 	HighCPUThreshold              float64       `json:"highCPUThreshold"`
 	HighCPUDuration               time.Duration `json:"highCPUDuration"`
 	HighCPUCooldown               time.Duration `json:"highCPUCooldown"`
+	Theme                         string        `json:"theme"`
 }
 
 const (
@@ -193,3 +195,12 @@ func NormalizeCPUDisplayMode(mode string) string {
 type Clock interface {
 	Now() time.Time
 }
+
+func NormalizeThemeMode(mode string) string {
+	switch mode {
+	case "light", "dark":
+		return mode
+	default:
+		return "system"
+	}
+}

internal/macos/menu/menu_bar_bridge.m

@@ -1,5 +1,6 @@
 #import <Cocoa/Cocoa.h>
 #import <ServiceManagement/ServiceManagement.h>
+#import <QuartzCore/QuartzCore.h>
 #import <math.h>
 #import <stdlib.h>
 #import <string.h>
@@ -112,6 +113,9 @@ - (void)drawRect:(NSRect)dirtyRect {
 @end
 
 static BOOL OpenTamerCommandShouldKeepMenuOpen(NSString *command) {
+    if ([command hasPrefix:@"pref-string|theme|"]) {
+        return NO;
+    }
     return [command hasPrefix:@"pref-"] ||
         [command hasPrefix:@"graph-window|"];
 }
@@ -236,7 +240,6 @@ - (instancetype)initWithFrame:(NSRect)frame {
     if (self == nil) {
         return nil;
     }
-    self.appearance = [NSAppearance appearanceNamed:NSAppearanceNameAqua];
     self.actions = [[NSMutableArray alloc] init];
     return self;
 }
@@ -262,7 +265,11 @@ - (NSView *)hitTest:(NSPoint)point {
 }
 
 - (void)drawRect:(NSRect)dirtyRect {
-    [[NSColor colorWithCalibratedWhite:0.985 alpha:1.0] setFill];
+    if ([self.effectiveAppearance.name containsString:@"Dark"]) {
+        [[NSColor colorWithCalibratedWhite:0.12 alpha:1.0] setFill];
+    } else {
+        [[NSColor colorWithCalibratedWhite:0.985 alpha:1.0] setFill];
+    }
     NSRectFill(self.bounds);
 
     for (NSDictionary *action in self.actions) {
@@ -383,7 +390,12 @@ - (void)drawToggleAction:(NSDictionary *)action {
 - (void)drawButtonAction:(NSDictionary *)action {
     NSRect bounds = [action[@"frame"] rectValue];
     NSString *title = [action[@"title"] isKindOfClass:NSString.class] ? action[@"title"] : @"";
-    [[NSColor colorWithCalibratedWhite:0.92 alpha:1.0] setFill];
+
+    if ([self.effectiveAppearance.name containsString:@"Dark"]) {
+        [[NSColor colorWithCalibratedWhite:0.22 alpha:1.0] setFill];
+    } else {
+        [[NSColor colorWithCalibratedWhite:0.92 alpha:1.0] setFill];
+    }
     [[NSBezierPath bezierPathWithRoundedRect:bounds xRadius:6 yRadius:6] fill];
 
     NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
@@ -400,7 +412,12 @@ - (void)drawButtonAction:(NSDictionary *)action {
 
 - (void)drawProcessAction:(NSDictionary *)action {
     NSRect bounds = NSInsetRect([action[@"frame"] rectValue], 2, 2);
-    [[NSColor colorWithCalibratedWhite:1.0 alpha:0.72] setFill];
+
+    if ([self.effectiveAppearance.name containsString:@"Dark"]) {
+        [[NSColor colorWithCalibratedWhite:0.18 alpha:0.72] setFill];
+    } else {
+        [[NSColor colorWithCalibratedWhite:1.0 alpha:0.72] setFill];
+    }
     [[NSBezierPath bezierPathWithRoundedRect:bounds xRadius:6 yRadius:6] fill];
 
     NSDictionary *row = [action[@"row"] isKindOfClass:NSDictionary.class] ? action[@"row"] : @{};
@@ -435,11 +452,11 @@ - (void)drawProcessAction:(NSDictionary *)action {
     };
 
     CGFloat valueWidth = [kind isEqualToString:@"managed"] ? 162 : 116;
-    NSRect valueRect = NSMakeRect(NSMaxX(bounds) - valueWidth - 8, NSMinY(bounds) + 6, valueWidth, 16);
+    NSRect valueRect = NSMakeRect(NSMaxX(bounds) - valueWidth - 8, NSMinY(bounds) + 2, valueWidth, 16);
     CGFloat nameX = NSMinX(bounds) + 8;
     id graphColorIndex = action[@"graphColorIndex"];
     if (graphColorIndex != nil && graphColorIndex != [NSNull null] && [graphColorIndex respondsToSelector:@selector(unsignedIntegerValue)]) {
-        NSRect dotRect = NSMakeRect(nameX, NSMinY(bounds) + 8, 8, 8);
+        NSRect dotRect = NSMakeRect(nameX, NSMinY(bounds) + 6, 8, 8);
         NSColor *dotColor = OpenTamerGraphColor([graphColorIndex unsignedIntegerValue]);
         NSBezierPath *dotPath = [NSBezierPath bezierPathWithOvalInRect:dotRect];
         BOOL graphLineHidden = [action[@"graphLineHidden"] boolValue];
@@ -461,7 +478,7 @@ - (void)drawProcessAction:(NSDictionary *)action {
         }
         nameX += 16;
     }
-    NSRect nameRect = NSMakeRect(nameX, NSMinY(bounds) + 6, MAX((CGFloat)0, NSMinX(valueRect) - nameX - 2), 16);
+    NSRect nameRect = NSMakeRect(nameX, NSMinY(bounds) + 2, MAX((CGFloat)0, NSMinX(valueRect) - nameX - 2), 16);
     [name drawInRect:nameRect withAttributes:nameAttrs];
     [right drawInRect:valueRect withAttributes:valueAttrs];
 }
@@ -574,7 +591,12 @@ - (void)drawYAxisForPlot:(NSRect)plot maximum:(double)maximum {
 
 - (void)drawRect:(NSRect)dirtyRect {
     NSRect bounds = NSInsetRect(self.bounds, 1, 1);
-    [[NSColor colorWithCalibratedWhite:1.0 alpha:1.0] setFill];
+
+    if ([self.effectiveAppearance.name containsString:@"Dark"]) {
+        [[NSColor colorWithCalibratedWhite:0.15 alpha:1.0] setFill];
+    } else {
+        [[NSColor colorWithCalibratedWhite:1.0 alpha:1.0] setFill];
+    }
     [[NSBezierPath bezierPathWithRoundedRect:bounds xRadius:8 yRadius:8] fill];
 
     NSRect plot = NSMakeRect(NSMinX(bounds) + 12, NSMinY(bounds) + 14, NSWidth(bounds) - 58, NSHeight(bounds) - 28);
@@ -675,6 +697,19 @@ - (instancetype)initWithState:(NSDictionary *)state {
 - (void)install {
     self.statusItem = [NSStatusBar.systemStatusBar statusItemWithLength:NSVariableStatusItemLength];
     self.statusItem.menu = nil;
+
+    // 💡 Apply user configuration choices directly to the application context on startup boots
+    if (@available(macOS 10.14, *)) {
+        NSAppearance *appAppearance = nil;
+        NSString *theme = [self stringPreference:@"theme" fallback:@"system"];
+        if ([theme isEqualToString:@"dark"]) {
+            appAppearance = [NSAppearance appearanceNamed:NSAppearanceNameDarkAqua];
+        } else if ([theme isEqualToString:@"light"]) {
+            appAppearance = [NSAppearance appearanceNamed:NSAppearanceNameAqua];
+        }
+        NSApp.appearance = appAppearance;
+    }
+
     [self updateStatusTitle];
     [self updateTrackedStatusItems];
     [self rebuildMenu];
@@ -683,12 +718,30 @@ - (void)install {
 - (void)updateWithState:(NSDictionary *)state {
     self.state = state ?: @{};
     [self pruneHiddenGraphAppKeys];
+
+    if (@available(macOS 10.14, *)) {
+        NSAppearance *appAppearance = nil;
+        NSString *theme = [self stringPreference:@"theme" fallback:@"system"];
+        if ([theme isEqualToString:@"dark"]) {
+            appAppearance = [NSAppearance appearanceNamed:NSAppearanceNameDarkAqua];
+        } else if ([theme isEqualToString:@"light"]) {
+            appAppearance = [NSAppearance appearanceNamed:NSAppearanceNameAqua];
+        }
+        NSApp.appearance = appAppearance;
+    }
+
     [self updateStatusTitle];
     [self updateTrackedStatusItems];
+
     if (self.primaryPopover.isShown) {
+        self.primaryPopover.appearance = NSApp.appearance;
+        if (self.primaryPopover.contentViewController.view.window) {
+            self.primaryPopover.contentViewController.view.window.appearance = NSApp.appearance;
+        }
         [self refreshPrimaryPopoverContent];
         return;
     }
+
     if (self.menuVisible) {
         self.needsMenuRebuild = YES;
     } else {
@@ -1664,6 +1717,12 @@ - (NSMenu *)preferencesMenu {
                                  labels:@[@"Per-Core Process CPU", @"System Normalized CPU"]
                                  values:@[@"per_core_process", @"system_normalized"]
                                  toMenu:generalMenu];
+    [self addStringPreferenceWithTitle:@"Theme"
+                                    key:@"theme"
+                               fallback:@"system"
+                                 labels:@[@"System theme", @"Light", @"Dark"]
+                                 values:@[@"system", @"light", @"dark"]
+                                 toMenu:generalMenu];                                 
     [self addDurationPreferenceWithTitle:@"Wake Grace"
                                      key:@"wakeGrace"
                                 fallback:30
@@ -1909,6 +1968,8 @@ - (OpenTamerPanelView *)primaryPanelView {
 
     OpenTamerPanelView *view = [[OpenTamerPanelView alloc] initWithFrame:NSMakeRect(0, 0, width, height)];
     view.controller = (id<OpenTamerPanelActionHandling>)self;
+    view.appearance = NSApp.appearance;
+
     CGFloat y = 12;
     NSDictionary *graphColorIndexesByAppKey = [self graphColorIndexesByAppKey];
 
@@ -1944,6 +2005,7 @@ - (OpenTamerPanelView *)primaryPanelView {
     y += 18;
 
     OpenTamerCPUGraphView *graph = [[OpenTamerCPUGraphView alloc] initWithFrame:NSMakeRect(padding, y, width - padding * 2, 118)];
+    graph.appearance = NSApp.appearance;
     graph.lines = [self cpuGraphLines];
     graph.hiddenAppKeys = [self.hiddenGraphAppKeys copy];
     graph.currentCPU = [self cpuGraphCurrentCPU];
@@ -2009,7 +2071,7 @@ - (void)showPrimaryPopover {
     popover.behavior = NSPopoverBehaviorTransient;
     popover.animates = NO;
     popover.delegate = self;
-    popover.appearance = [NSAppearance appearanceNamed:NSAppearanceNameAqua];
+    popover.appearance = NSApp.appearance;
 
     NSViewController *viewController = [[NSViewController alloc] init];
     viewController.view = [self primaryPanelView];

internal/macos/menu/menu_bar_darwin.go

@@ -3,7 +3,7 @@
 package menu
 
 /*
-#cgo darwin LDFLAGS: -framework Cocoa -framework ServiceManagement
+#cgo darwin LDFLAGS: -framework Cocoa -framework ServiceManagement -framework QuartzCore
 #include <stdlib.h>
 #include "menu_bar_bridge.h"
 */

internal/macos/menu/menu_bar_preferences_test.go

@@ -43,6 +43,7 @@ func TestPreferencesMenuExposesExpectedConfigKeys(t *testing.T) {
 		"highCPUThreshold",
 		"showMenuBarIcon",
 		"statsInterval",
+		"theme",
 		"topProcessesSort",
 		"wakeGrace",
 	}

internal/ui/preferences.go

@@ -43,6 +43,7 @@ const (
 	PreferenceHighCPUThreshold              PreferenceField = "highCPUThreshold"
 	PreferenceHighCPUDuration               PreferenceField = "highCPUDuration"
 	PreferenceHighCPUCooldown               PreferenceField = "highCPUCooldown"
+	PreferenceTheme                         PreferenceField = "theme"
 )
 
 type PreferencesCommand struct {
@@ -192,6 +193,12 @@ func setStringPreference(preferences *core.GlobalPreferences, field PreferenceFi
 			return fmt.Errorf("unsupported CPU display mode %q", value)
 		}
 		preferences.CPUDisplayMode = normalized
+	case PreferenceTheme: // 👈 Add this entire block!
+		normalized := core.NormalizeThemeMode(value)
+		if normalized != value {
+			return fmt.Errorf("unsupported theme mode %q", value)
+		}
+		preferences.Theme = normalized
 	default:
 		return fmt.Errorf("unsupported string preference %q", field)
 	}