/*

     File: AudioEngine.h

 Abstract: 

  Version: 1.1.2

 Disclaimer: IMPORTANT:  This Apple software is supplied to you by Apple

 Inc. ("Apple") in consideration of your agreement to the following

 terms, and your use, installation, modification or redistribution of

 this Apple software constitutes acceptance of these terms.  If you do

 not agree with these terms, please do not use, install, modify or

 redistribute this Apple software.

 In consideration of your agreement to abide by the following terms, and

 subject to these terms, Apple grants you a personal, non-exclusive

 license, under Apple's copyrights in this original Apple software (the

 "Apple Software"), to use, reproduce, modify and redistribute the Apple

 Software, with or without modifications, in source and/or binary forms;

 provided that if you redistribute the Apple Software in its entirety and

 without modifications, you must retain this notice and the following

 text and disclaimers in all such redistributions of the Apple Software.

 Neither the name, trademarks, service marks or logos of Apple Inc. may

 be used to endorse or promote products derived from the Apple Software

 without specific prior written permission from Apple.  Except as

 expressly stated in this notice, no other rights or licenses, express or

 implied, are granted by Apple herein, including but not limited to any

 patent rights that may be infringed by your derivative works or by other

 works in which the Apple Software may be incorporated.

 The Apple Software is provided by Apple on an "AS IS" basis.  APPLE

 MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION

 THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS

 FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND

 OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.

 IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL

 OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION,

 MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED

 AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE),

 STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE

 POSSIBILITY OF SUCH DAMAGE.

 Copyright (C) 2014 Apple Inc. All Rights Reserved.

 */

#import <Foundation/Foundation.h>

#import <AVFoundation/AVAudioSession.h>

#import <AudioUnit/AudioUnit.h>

#import <AudioUnit/AudioComponent.h>

#import <AudioToolbox/AudioToolbox.h>

#import <AudioToolbox/AudioFile.h>

#import <AudioUnit/AudioUnitProperties.h>

#import <CoreFoundation/CFNotificationCenter.h>

#import <AudioToolbox/AUGraph.h>

#import "CAAudioUnitOutputCapturer.h"

#import "CAStreamBasicDescription.h"

#import "CAUIKeyboardView.h"

NSString *formattedTimeStringForFrameCount(UInt64 inFrameCount, Float64 inSampleRate, BOOL inShowMilliseconds);

void displayAlertDialog(NSString *title, NSString *message);

#define Check(expr) do { OSStatus err = (expr); if (err) { NSLog(@"error %d from %s", (int)err, #expr); abort(); } } while (0)

#define NSCheck(expr) do { NSError *err = nil; if (!(expr)) { NSLog(@"error from %s: %@", #expr, err);  abort(); } } while (0)

//Notification to refresh the transport UI. Fired when engine state has changed

FOUNDATION_EXPORT NSString * const kTransportStateChangedNotification;

//Midi related constants

enum {

    kMidiMessage_ControlChange      = 0xB,

    kMidiMessage_ProgramChange      = 0xC,

    kMidiMessage_BankMSBControl     = 0,

    kMidiMessage_BankLSBControl     = 32,

    kMidiMessage_NoteOn             = 0x9,

    kMidiMessage_NoteOff            = 0x8,

    kMidiController_AllNotesOff     = 123

};

//Transport state enum

typedef NS_ENUM(NSInteger, TransportState) {

    TransportStateRecording = 0,

    TransportStatePlaying,

    TransportStatePaused,

    TransportStateStopped

};

//Structure used to playback audio files with audio units

typedef struct AUGraphPlayer {

    AudioStreamBasicDescription inputFormat;

    AudioFileID                 inputFile;

    AUGraph                     graph;

    AudioUnit                   fileAU;

}AUGraphPlayer;

//object representing a remote audio unit

@interface RemoteAU : NSObject {

@public

    AudioComponentDescription _desc;

    AudioComponent _comp;

    NSString *_name;

    UIImage *_image;

}

@end

//Close a view once we are done with it

@protocol ReturnToParentViewControllerDelegate <NSObject>

- (void) closeView;

@end

@protocol AudioEngineDelegate;

@interface AudioEngine : NSObject<CAUIKeyboardEngine> {

@private

    NSMutableArray *_remoteEffects;

    NSMutableArray *_connectedNodes;

    AUGraph     hostGraph;

    AudioUnit   instrument;

    AudioUnit   effect;

    AudioUnit   mixerUnit;

    AudioUnit   outputUnit;

    AudioUnit   filePlayerUnit;

    AUNode      outNode, instrumentNode, mixerNode, filePlayerNode, effectNode;

    UInt32      busCount;       // bus count for mixer unit input

    UInt32      playerBus;      // mixer unit bus 0 will be stereo and will take the filePlayer

    UInt32      remoteBus;      // mixer unit bus 1 will be stereo and will take the remote instrument/effects

    NSURL                       *fileURL;

    AUGraphPlayer               filePlayer;

    CAAudioUnitOutputCapturer   *recorder;

    AudioStreamBasicDescription stereoStreamFormat;

    CAStreamBasicDescription    tapFormat;

    SInt64 durationOfFile;

    TransportState state;

    Boolean _engineStarted, graphStarted;

    bool canPlay, canRewind;

    /*Key: name of class that block comes from. Value: function to be called when engine changes  */

    NSMutableDictionary *_engineObservers;

    ScheduledAudioFileRegion    mScheduledRegion;

    SInt64                      mTranslatedLastTimeRendered;

    SInt64                      mInitialRegionOffset;

}

// Graph Interrogation Methods

- (NSUInteger) getNumberOfConnectedNodes;

- (RemoteAU *) getNodeAt:(int) index;

- (BOOL) isRemoteInstrumentConnected;

- (BOOL) isRemoteEffectConnected;

- (void) gotoRemoteInstrument;

- (void) gotoRemoteEffect;

- (void) disconnectInstrument;

- (void) disconnectEffect;

- (void) destroyRemoteAU:(AudioUnit) remoteAU;

- (BOOL) addRemoteAU:(RemoteAU *)rau;

- (void) checkStartStopGraph;

- (void) startPlaying;

- (void) stopPlaying;

- (void) stopRecording;

- (BOOL) canRewind;

- (BOOL) canPlay;

- (BOOL) canRecord;

- (BOOL) isPlaying;

- (BOOL) isPaused;

- (BOOL) isRecording;

- (void) rewind;

- (void) togglePlay;

- (void) toggleRecord;

- (void) seekPlayheadTo:(CGFloat) position;

- (void) synchronizeFilePlayerState:(BOOL) fromTimer;

- (SInt64) getAmountPlayed;

- (NSString *) getDurationString;

- (NSString *) getPlayTimeString;

- (float) getPlayProgress;

- (void) addEngineObserver:(dispatch_block_t) inObserver key:(NSString*) inKey;

- (void) notifyObservers;

@end