SSYAlertSounder.m

#import "SSYAlertSounder.h"
#import <AudioToolbox/AudioServices.h>

static SSYAlertSounder* static_sharedSounder = nil ;

@interface SSYAlertSounder ()

@end

@implementation SSYAlertSounder

- (id)init {
	self = [super init] ;
	if (self) {
		m_soundIds = [[NSMutableDictionary alloc] init] ;
	}
	
	return self ;
}

- (void)dealloc {
	for (NSNumber* soundId in [m_soundIds allValues]) {
		AudioServicesDisposeSystemSoundID([soundId longValue]) ;
	}
	
	[m_soundIds release] ;
	
	[super dealloc] ;
}

- (NSMutableDictionary*)soundIds {
	return m_soundIds ;
}


+ (SSYAlertSounder*)sharedSounder {
	@synchronized(self) {
        if (!static_sharedSounder) {
            static_sharedSounder = [[self alloc] init] ;
        }
    }
	
	// No autorelease.  This sticks around forever.
    return static_sharedSounder ;
}

- (SystemSoundID)soundIdForPath:(NSString*)path
					 rememberAs:(NSString*)name {
	SystemSoundID soundId = 0 ;
	
	if (path) {
		CFURLRef url = (CFURLRef)[NSURL fileURLWithPath:path] ;
		if (url) {
			OSStatus err ;
			err = AudioServicesCreateSystemSoundID(url, &soundId) ;
			
			if (err) {
				// This will happen if file was not found.
				soundId = 0 ;
			}
			else {
				[[self soundIds] setObject:[NSNumber numberWithLong:soundId]
									forKey:name] ;
			}
		}
	}
	
	return soundId ;
}


- (void)playAlertSoundNamed:(NSString*)name {
	// First, see if we've got this sound cached
	SystemSoundID soundId = [[[self soundIds] objectForKey:name] longValue] ;
	// Used -longValue because SystemSoundID is a UInt32
	
	NSString* path ;
	
	// If not found, look in the current application's bundle
	if (!soundId) {
		path = [[NSBundle mainBundle] pathForResource:name
											   ofType:@"aiff"] ;

		soundId = [self soundIdForPath:path
							rememberAs:name] ;
		// If not found, look in current user's library
		if (!soundId) {
			path = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Sounds"] ;
			path = [path stringByAppendingPathComponent:[name stringByAppendingPathExtension:@"aiff"]] ;
			
			soundId = [self soundIdForPath:path
								rememberAs:name] ;

			// If not found, look in system's library
			if (!soundId) {
				path = @"/System/Library/Sounds" ;
				path = [path stringByAppendingPathComponent:[name stringByAppendingPathExtension:@"aiff"]] ;
				
				soundId = [self soundIdForPath:path
									rememberAs:name] ;
			}		
		}		
	}
	
	if (soundId) {
		AudioServicesPlayAlertSound(soundId) ;
	}
	else {
		NSBeep() ;
	}
}

@end