[Feature] Add option to duck music player volume instead of pausing (#541)

BGMApp/BGMApp/BGMAutoPauseMenuItem.m

@@ -30,7 +30,8 @@
 
 #pragma clang assume_nonnull begin
 
-static NSString* const kMenuItemTitleFormat = @"Auto-pause %@";
+static NSString* const kMenuItemTitleFormatPause = @"Auto-pause %@";
+static NSString* const kMenuItemTitleFormatDuck = @"Auto-duck %@";
 static NSString* const kMenuItemDisabledToolTipFormat = @"%@ doesn't appear to be running.";
 
 // Wait time to disable/enable the auto-pause menu item, in seconds.
@@ -123,7 +124,8 @@ - (void) updateMenuItemTitle {
 - (void) updateMenuItemTitleWithHighlight:(BOOL)highlight {
     // Set the title of the Auto-pause Music menu item, including the name of the selected music player.
     NSString* musicPlayerName = musicPlayers.selectedMusicPlayer.name;
-    menuItem.title = [NSString stringWithFormat:kMenuItemTitleFormat, musicPlayerName];
+    NSString* titleFormat = userDefaults.autoDuckMusic ? kMenuItemTitleFormatDuck : kMenuItemTitleFormatPause;
+    menuItem.title = [NSString stringWithFormat:titleFormat, musicPlayerName];
 
     // Make the Auto-pause Music menu item appear disabled if the application is not running.
     //

BGMApp/BGMApp/BGMUserDefaults.h

@@ -44,6 +44,8 @@
 @property NSString* __nullable selectedMusicPlayerID;
 
 @property BOOL autoPauseMusicEnabled;
+@property BOOL autoDuckMusic;
+@property NSUInteger autoDuckPercent;
 
 // The UIDs of the output devices most recently selected by the user. The most-recently selected
 // device is at index 0. See BGMPreferredOutputDevices.

BGMApp/BGMApp/BGMUserDefaults.m

@@ -31,6 +31,8 @@
 
 // Keys
 static NSString* const kDefaultKeyAutoPauseMusicEnabled = @"AutoPauseMusicEnabled";
+static NSString* const kDefaultKeyAutoDuckMusic          = @"AutoDuckMusic";
+static NSString* const kDefaultKeyAutoDuckPercent        = @"AutoDuckPercent";
 static NSString* const kDefaultKeySelectedMusicPlayerID = @"SelectedMusicPlayerID";
 static NSString* const kDefaultKeyPreferredDeviceUIDs   = @"PreferredDeviceUIDs";
 static NSString* const kDefaultKeyStatusBarIcon         = @"StatusBarIcon";
@@ -62,7 +64,9 @@ - (instancetype) initWithDefaults:(NSUserDefaults* __nullable)inDefaults {
         NSDictionary* defaultsDict = @{ 
             kDefaultKeyAutoPauseMusicEnabled: @YES,
             kDefaultKeyPauseDelayMS: @1500,
-            kDefaultKeyMaxUnpauseDelayMS: @3500
+            kDefaultKeyMaxUnpauseDelayMS: @3500,
+            kDefaultKeyAutoDuckMusic: @NO,
+            kDefaultKeyAutoDuckPercent: @30
         };
 
         if (defaults) {
@@ -95,6 +99,26 @@ - (void) setAutoPauseMusicEnabled:(BOOL)autoPauseMusicEnabled {
     [self setBool:kDefaultKeyAutoPauseMusicEnabled to:autoPauseMusicEnabled];
 }
 
+#pragma mark Auto-duck
+
+- (BOOL) autoDuckMusic {
+    return [self getBool:kDefaultKeyAutoDuckMusic];
+}
+
+- (void) setAutoDuckMusic:(BOOL)autoDuckMusic {
+    [self setBool:kDefaultKeyAutoDuckMusic to:autoDuckMusic];
+}
+
+- (NSUInteger) autoDuckPercent {
+    NSInteger percent = [self getInt:kDefaultKeyAutoDuckPercent or:30];
+    return (NSUInteger)MAX(0, MIN(100, percent));
+}
+
+- (void) setAutoDuckPercent:(NSUInteger)autoDuckPercent {
+    NSUInteger clampedPercent = MAX(0, MIN(100, autoDuckPercent));
+    [self setInt:kDefaultKeyAutoDuckPercent to:(NSInteger)clampedPercent];
+}
+
 #pragma mark Auto-pause Delays
 
 - (NSUInteger) pauseDelayMS {

BGMApp/BGMApp/Preferences/BGMAutoPauseMusicPrefs.h

@@ -34,7 +34,8 @@
 
 - (id) initWithPreferencesMenu:(NSMenu*)inPrefsMenu
                   audioDevices:(BGMAudioDeviceManager*)inAudioDevices
-                  musicPlayers:(BGMMusicPlayers*)inMusicPlayers;
+                  musicPlayers:(BGMMusicPlayers*)inMusicPlayers
+                  userDefaults:(BGMUserDefaults*)inUserDefaults;
 
 @end
 

BGMApp/BGMApp/Preferences/BGMAutoPauseMusicPrefs.mm

@@ -26,6 +26,7 @@
 // Local Includes
 #import "BGM_Types.h"
 #import "BGMMusicPlayer.h"
+#import "BGMUserDefaults.h"
 
 
 #pragma clang assume_nonnull begin
@@ -36,17 +37,20 @@
 @implementation BGMAutoPauseMusicPrefs {
     BGMAudioDeviceManager* audioDevices;
     BGMMusicPlayers* musicPlayers;
+    BGMUserDefaults* userDefaults;
     NSMenu* prefsMenu;
     NSArray<NSMenuItem*>* musicPlayerMenuItems;
 }
 
 - (id) initWithPreferencesMenu:(NSMenu*)inPrefsMenu
                   audioDevices:(BGMAudioDeviceManager*)inAudioDevices
-                  musicPlayers:(BGMMusicPlayers*)inMusicPlayers {
+                  musicPlayers:(BGMMusicPlayers*)inMusicPlayers
+                  userDefaults:(BGMUserDefaults*)inUserDefaults {
     if ((self = [super init])) {
         prefsMenu = inPrefsMenu;
         audioDevices = inAudioDevices;
         musicPlayers = inMusicPlayers;
+        userDefaults = inUserDefaults;
 
         musicPlayerMenuItems = @[];
 
@@ -96,6 +100,17 @@ - (void) initPreferencesMenuSection {
         menuItem.target = self;
         menuItem.indentationLevel = 1;
     }
+
+    // Add "Duck instead of pause" menu item below the music players
+    NSInteger duckMusicItemIndex = musicPlayerItemsIndex + musicPlayers.musicPlayers.count;
+    NSMenuItem* duckMusicMenuItem = [prefsMenu insertItemWithTitle:@"Duck instead of pause"
+                                                            action:@selector(handleDuckMusicChange:)
+                                                     keyEquivalent:@""
+                                                           atIndex:duckMusicItemIndex];
+    duckMusicMenuItem.representedObject = nil;
+    duckMusicMenuItem.target = self;
+    duckMusicMenuItem.indentationLevel = 1;
+    duckMusicMenuItem.state = userDefaults.autoDuckMusic ? NSOnState : NSOffState;
 }
 
 - (void) handleMusicPlayerChange:(NSMenuItem*)sender {
@@ -112,6 +127,12 @@ - (void) handleMusicPlayerChange:(NSMenuItem*)sender {
     }
 }
 
+- (void) handleDuckMusicChange:(NSMenuItem*)sender {
+    BOOL nextState = (sender.state == NSOffState);
+    sender.state = nextState ? NSOnState : NSOffState;
+    userDefaults.autoDuckMusic = nextState;
+}
+
 @end
 
 #pragma clang assume_nonnull end

BGMApp/BGMApp/Preferences/BGMPreferencesMenu.mm

@@ -59,6 +59,11 @@ @implementation BGMPreferencesMenu {
     NSTextField* pauseDelayLabel;
     NSTextField* maxUnpauseDelayLabel;
     BGMUserDefaults* userDefaults;
+
+    // Ducking preferences
+    NSMenuItem* duckVolumeMenuItem;
+    NSSlider* duckVolumeSlider;
+    NSTextField* duckVolumeLabel;
 }
 
 - (id) initWithBGMMenu:(NSMenu*)inBGMMenu
@@ -73,7 +78,8 @@ - (id) initWithBGMMenu:(NSMenu*)inBGMMenu
 
         autoPauseMusicPrefs = [[BGMAutoPauseMusicPrefs alloc] initWithPreferencesMenu:prefsMenu
                                                                          audioDevices:inAudioDevices
-                                                                         musicPlayers:inMusicPlayers];
+                                                                         musicPlayers:inMusicPlayers
+                                                                         userDefaults:inUserDefaults];
 
         aboutPanel = [[BGMAboutPanel alloc] initWithPanel:inAboutPanel licenseView:inAboutPanelLicenseView];
 
@@ -100,6 +106,11 @@ - (id) initWithBGMMenu:(NSMenu*)inBGMMenu
         // Set up delay preferences
         userDefaults = inUserDefaults;
         [self setupDelayPreferences:prefsMenu];
+
+        [userDefaults addObserver:self
+                       forKeyPath:@"autoDuckMusic"
+                          options:NSKeyValueObservingOptionNew
+                          context:nil];
     }
 
     return self;
@@ -194,8 +205,36 @@ - (void) setupDelayPreferences:(NSMenu*)prefsMenu {
 
     maxUnpauseDelayMenuItem.view = maxUnpauseDelayView;
     [prefsMenu addItem:maxUnpauseDelayMenuItem];
+
+    // Create ducking volume menu item with slider
+    duckVolumeMenuItem = [[NSMenuItem alloc] initWithTitle:@"" action:nil keyEquivalent:@""];
+    NSView* duckVolumeView = [[NSView alloc] initWithFrame:NSMakeRect(0, 0, 280, 25)];
+
+    // Ducking volume label
+    NSTextField* duckVolumeTitleLabel = [[NSTextField alloc] initWithFrame:NSMakeRect(10, 5, 110, 15)];
+    duckVolumeTitleLabel.stringValue = @"Ducking Volume:";
+    duckVolumeTitleLabel.editable = NO;
+    duckVolumeTitleLabel.bordered = NO;
+    duckVolumeTitleLabel.backgroundColor = [NSColor clearColor];
+    duckVolumeTitleLabel.font = [NSFont menuFontOfSize:13];
+    [duckVolumeView addSubview:duckVolumeTitleLabel];
+
+    // Ducking volume slider
+    duckVolumeSlider = [[NSSlider alloc] initWithFrame:NSMakeRect(115, 5, 100, 15)];
+    [duckVolumeView addSubview:duckVolumeSlider];
+
+    // Ducking volume value label
+    duckVolumeLabel = [[NSTextField alloc] initWithFrame:NSMakeRect(220, 5, 55, 15)];
+    duckVolumeLabel.editable = NO;
+    duckVolumeLabel.bordered = NO;
+    duckVolumeLabel.backgroundColor = [NSColor clearColor];
+    duckVolumeLabel.font = [NSFont menuFontOfSize:11];
+    [duckVolumeView addSubview:duckVolumeLabel];
 
-    // Initialize the delay sliders with current values and targets
+    duckVolumeMenuItem.view = duckVolumeView;
+    [prefsMenu addItem:duckVolumeMenuItem];
+
+    // Initialize the sliders with current values and targets
     [self initDelaySliders];
 }
 
@@ -215,10 +254,19 @@ - (void) initDelaySliders {
     maxUnpauseDelaySlider.integerValue = [self msToSliderValue:userDefaults.maxUnpauseDelayMS];
     maxUnpauseDelaySlider.target = self;
     maxUnpauseDelaySlider.action = @selector(maxUnpauseDelaySliderChanged:);
+
+    // Configure ducking volume slider (0% to 100%)
+    duckVolumeSlider.minValue = 0;
+    duckVolumeSlider.maxValue = 100;
+    duckVolumeSlider.integerValue = userDefaults.autoDuckPercent;
+    duckVolumeSlider.target = self;
+    duckVolumeSlider.action = @selector(duckVolumeSliderChanged:);
 
     // Update labels with current values
     [self updatePauseDelayLabel];
     [self updateMaxUnpauseDelayLabel];
+    [self updateDuckVolumeLabel];
+    [self updateSliderStates];
 }
 
 - (void) pauseDelaySliderChanged:(NSSlider*)sender {
@@ -284,6 +332,45 @@ - (NSInteger) msToSliderValue:(NSUInteger)ms {
     return (NSInteger)MIN(MAX(sliderValue, 0), 100);
 }
 
+- (void) dealloc {
+    try {
+        [userDefaults removeObserver:self forKeyPath:@"autoDuckMusic" context:nil];
+    } catch (const std::exception& e) {
+    }
+}
+
+- (void) observeValueForKeyPath:(NSString* __nullable)keyPath
+                       ofObject:(id __nullable)object
+                         change:(NSDictionary* __nullable)change
+                        context:(void* __nullable)context
+{
+    #pragma unused (object, change, context)
+    if ([keyPath isEqualToString:@"autoDuckMusic"]) {
+        dispatch_async(dispatch_get_main_queue(), ^{
+            [self updateSliderStates];
+        });
+    }
+}
+
+- (void) duckVolumeSliderChanged:(NSSlider*)sender {
+    userDefaults.autoDuckPercent = (NSUInteger)sender.integerValue;
+    [self updateDuckVolumeLabel];
+}
+
+- (void) updateDuckVolumeLabel {
+    duckVolumeLabel.stringValue = [NSString stringWithFormat:@"%lu%%", (unsigned long)userDefaults.autoDuckPercent];
+}
+
+- (void) updateSliderStates {
+    BOOL duckEnabled = userDefaults.autoDuckMusic;
+    duckVolumeSlider.enabled = duckEnabled;
+    if (duckEnabled) {
+        duckVolumeLabel.textColor = [NSColor controlTextColor];
+    } else {
+        duckVolumeLabel.textColor = [NSColor disabledControlTextColor];
+    }
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

BGMApp/BGMAppTests/UnitTests/BGMMusicPlayersUnitTests.mm

@@ -100,6 +100,22 @@ - (void) setAutoPauseMusicEnabled:(BOOL)autoPauseMusicEnabled {
     #pragma unused (autoPauseMusicEnabled)
 }
 
+- (BOOL) autoDuckMusic {
+    return NO;
+}
+
+- (void) setAutoDuckMusic:(BOOL)autoDuckMusic {
+    #pragma unused (autoDuckMusic)
+}
+
+- (NSUInteger) autoDuckPercent {
+    return 30;
+}
+
+- (void) setAutoDuckPercent:(NSUInteger)autoDuckPercent {
+    #pragma unused (autoDuckPercent)
+}
+
 @end
 
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