cog/AudioScrobbler/AudioScrobbler.m

/*
 *  $Id: AudioScrobbler.m 238 2007-01-26 22:55:20Z stephen_booth $
 *
 *  Copyright (C) 2006 - 2007 Stephen F. Booth <me@sbooth.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#import "AudioScrobbler.h"

#import "AudioScrobblerClient.h"
#import "PlaylistEntry.h"

// ========================================
// Symbolic Constants
// ========================================
NSString * const	AudioScrobblerRunLoopMode			= @"org.cogx.Cog.AudioScrobbler.RunLoopMode";

// ========================================
// Helpers
// ========================================
static NSString * 
escapeForLastFM(NSString *string)
{
	NSMutableString *result = [string mutableCopy];
	
	[result replaceOccurrencesOfString:@"&" 
							withString:@"&&" 
							   options:NSLiteralSearch 
								 range:NSMakeRange(0, [result length])];
	
	return (nil == result ? @"" : [result autorelease]);
}

@interface AudioScrobbler (Private)

- (NSMutableArray *)	queue;
- (NSString *)			pluginID;

- (void)				sendCommand:(NSString *)command;

- (BOOL)				keepProcessingAudioScrobblerCommands;
- (void)				setKeepProcessingAudioScrobblerCommands:(BOOL)keepProcessingAudioScrobblerCommands;

- (BOOL)				audioScrobblerThreadCompleted;
- (void)				setAudioScrobblerThreadCompleted:(BOOL)audioScrobblerThreadCompleted;

- (semaphore_t)			semaphore;

- (void)				processAudioScrobblerCommands:(id)unused;

@end

@implementation AudioScrobbler

- (id) init
{
	if((self = [super init])) {

		_pluginID = @"cog";

		if([[NSUserDefaults standardUserDefaults] boolForKey:@"automaticallyLaunchLastFM"])
			[[NSWorkspace sharedWorkspace] launchApplication:@"Last.fm.app"];
		
		_keepProcessingAudioScrobblerCommands = YES;

		kern_return_t result = semaphore_create(mach_task_self(), &_semaphore, SYNC_POLICY_FIFO, 0);
		
		if(KERN_SUCCESS != result) {
			NSLog(@"Couldn't create semaphore (%s).", mach_error_type(result));

			[self release];
			return nil;
		}
		
		[NSThread detachNewThreadSelector:@selector(processAudioScrobblerCommands:) toTarget:self withObject:nil];
	}
	return self;
}

- (void) dealloc
{
	if([self keepProcessingAudioScrobblerCommands] || NO == [self audioScrobblerThreadCompleted])
		[self shutdown];
	
	[_queue release], _queue = nil;
	
	semaphore_destroy(mach_task_self(), _semaphore), _semaphore = 0;

	[super dealloc];
}

- (void) start:(PlaylistEntry *)pe
{
        [self sendCommand:[NSString stringWithFormat:@"START c=%@&a=%@&t=%@&b=%@&m=%@&l=%i&p=%@\n", 
                [self pluginID],
                escapeForLastFM([pe artist]), 
                escapeForLastFM([pe title]), 
                escapeForLastFM([pe album]), 
                @"", // TODO: MusicBrainz support
                [[pe length] intValue],
                escapeForLastFM([[pe URL] path])
                ]];
}

- (void) stop
{
	[self sendCommand:[NSString stringWithFormat:@"STOP c=%@\n", [self pluginID]]];
}

- (void) pause
{
	[self sendCommand:[NSString stringWithFormat:@"PAUSE c=%@\n", [self pluginID]]];
}

- (void) resume
{
	[self sendCommand:[NSString stringWithFormat:@"RESUME c=%@\n", [self pluginID]]];
}

- (void) shutdown
{
	[self setKeepProcessingAudioScrobblerCommands:NO];
	semaphore_signal([self semaphore]);

	// Wait for the thread to terminate
	while(NO == [self audioScrobblerThreadCompleted])
		[[NSRunLoop currentRunLoop] runMode:AudioScrobblerRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:0.2]];
}

@end

@implementation AudioScrobbler (Private)

- (NSMutableArray *) queue
{
	if(nil == _queue)
		_queue = [[NSMutableArray alloc] init];
	
	return _queue;
}

- (NSString *) pluginID
{
	return _pluginID;
}

- (void) sendCommand:(NSString *)command
{
	@synchronized([self queue]) {
		[[self queue] addObject:command];
	}
	semaphore_signal([self semaphore]);
}

- (BOOL) keepProcessingAudioScrobblerCommands
{
	return _keepProcessingAudioScrobblerCommands;
}

- (void) setKeepProcessingAudioScrobblerCommands:(BOOL)keepProcessingAudioScrobblerCommands
{
	_keepProcessingAudioScrobblerCommands = keepProcessingAudioScrobblerCommands;
}

- (BOOL) audioScrobblerThreadCompleted
{
	return _audioScrobblerThreadCompleted;
}

- (void) setAudioScrobblerThreadCompleted:(BOOL)audioScrobblerThreadCompleted
{
	_audioScrobblerThreadCompleted = audioScrobblerThreadCompleted;
}

- (semaphore_t) semaphore
{
	return _semaphore;
}

- (void) processAudioScrobblerCommands:(id)unused
{
	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
	AudioScrobblerClient	*client				= [[AudioScrobblerClient alloc] init];
	mach_timespec_t			timeout				= { 5, 0 };
	NSEnumerator			*enumerator			= nil;
	NSString				*command			= nil;
	NSString				*response			= nil;
	in_port_t				port				= 33367;
	
	while([self keepProcessingAudioScrobblerCommands]) {
		NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

		// Get the first command to be sent
		@synchronized([self queue]) {
			enumerator	= [[self queue] objectEnumerator];
			command		= [[enumerator nextObject] retain];
		
			[[self queue] removeObjectIdenticalTo:command];
		}

		if(nil != command) { 
			@try {
				if([client connectToHost:@"localhost" port:port]) {
					port = [client connectedPort];
					[client send:command];
					[command release];
					
					response = [client receive];
					if(2 > [response length] || NSOrderedSame != [response compare:@"OK" options:NSLiteralSearch range:NSMakeRange(0,2)])
						NSLog(@"AudioScrobbler error: %@", response);
					
					[client shutdown];
				}
			}
			
			@catch(NSException *exception) {
				[client shutdown];
//				NSLog(@"Exception: %@",exception);
				[pool release];
				continue;
			}
		}
		
		semaphore_timedwait([self semaphore], timeout);
		[pool release];
	}
	
	// Send a final stop command to cleanup
	@try {
		if([client connectToHost:@"localhost" port:port]) {
			[client send:[NSString stringWithFormat:@"STOP c=%@\n", [self pluginID]]];
			
			response = [client receive];
			if(2 > [response length] || NSOrderedSame != [response compare:@"OK" options:NSLiteralSearch range:NSMakeRange(0,2)])
				NSLog(@"AudioScrobbler error: %@", response);
			
			[client shutdown];
		}
	}
	
	@catch(NSException *exception) {
		[client shutdown];
	}
	
	[client release];
	[self setAudioScrobblerThreadCompleted:YES];

	[pool release];
}

@end