/*  Copyright � 2007 Apple Inc. All Rights Reserved.

    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.

*/

#include <AudioToolbox/AudioToolbox.h>

#include "CAXException.h"

#include "CAStreamBasicDescription.h"

#include "CAAudioUnit.h"

void UsageString(int exitCode)

{

    printf ("Usage: PlayFile /path/to/file\n");

    exit(exitCode);

}

// helper functions

double PrepareFileAU (CAAudioUnit &au, CAStreamBasicDescription &fileFormat, AudioFileID audioFile);

void MakeSimpleGraph (AUGraph &theGraph, CAAudioUnit &fileAU, CAStreamBasicDescription &fileFormat, AudioFileID audioFile);

int main (int argc, char * const argv[]) 

{

    if (argc < 2) UsageString(1);

    AudioFileID audioFile;

    const char* inputFile = argv[1];

    CFURLRef theURL = CFURLCreateFromFileSystemRepresentation(kCFAllocatorDefault, (UInt8*)inputFile, strlen(inputFile), false);

    XThrowIfError (!theURL, "CFURLCreateFromFileSystemRepresentation");

    OSStatus err = AudioFileOpenURL (theURL, kAudioFileReadPermission, 0, &audioFile);

    CFRelease(theURL);

    XThrowIfError (err, "AudioFileOpenURL");

            // get the number of channels of the file

    CAStreamBasicDescription fileFormat;

    UInt32 propsize = sizeof(CAStreamBasicDescription);

    XThrowIfError (AudioFileGetProperty(audioFile, kAudioFilePropertyDataFormat, &propsize, &fileFormat), "AudioFileGetProperty");

    printf ("playing file: %s\n", inputFile);

    printf ("format: "); fileFormat.Print();

// lets set up our playing state now

    AUGraph theGraph;

    CAAudioUnit fileAU;

// this makes the graph, the file AU and sets it all up for playing

    MakeSimpleGraph (theGraph, fileAU, fileFormat, audioFile);

// now we load the file contents up for playback before we start playing

// this has to be done the AU is initialized and anytime it is reset or uninitialized

    Float64 fileDuration = PrepareFileAU (fileAU, fileFormat, audioFile);

        printf ("file duration: %f secs\n", fileDuration);

// start playing

    XThrowIfError (AUGraphStart (theGraph), "AUGraphStart");

// sleep until the file is finished

    usleep ((int)(fileDuration * 1000. * 1000.));

// lets clean up

    XThrowIfError (AUGraphStop (theGraph), "AUGraphStop");

    XThrowIfError (AUGraphUninitialize (theGraph), "AUGraphUninitialize");

    XThrowIfError (AudioFileClose (audioFile), "AudioFileClose");

    XThrowIfError (AUGraphClose (theGraph), "AUGraphClose");

    return 0;

}   

double PrepareFileAU (CAAudioUnit &au, CAStreamBasicDescription &fileFormat, AudioFileID audioFile)

{   

// 

        // calculate the duration

    UInt64 nPackets;

    UInt32 propsize = sizeof(nPackets);

    XThrowIfError (AudioFileGetProperty(audioFile, kAudioFilePropertyAudioDataPacketCount, &propsize, &nPackets), "kAudioFilePropertyAudioDataPacketCount");

    Float64 fileDuration = (nPackets * fileFormat.mFramesPerPacket) / fileFormat.mSampleRate;

    ScheduledAudioFileRegion rgn;

    memset (&rgn.mTimeStamp, 0, sizeof(rgn.mTimeStamp));

    rgn.mTimeStamp.mFlags = kAudioTimeStampSampleTimeValid;

    rgn.mTimeStamp.mSampleTime = 0;

    rgn.mCompletionProc = NULL;

    rgn.mCompletionProcUserData = NULL;

    rgn.mAudioFile = audioFile;

    rgn.mLoopCount = 1;

    rgn.mStartFrame = 0;

    rgn.mFramesToPlay = UInt32(nPackets * fileFormat.mFramesPerPacket);

        // tell the file player AU to play all of the file

    XThrowIfError (au.SetProperty (kAudioUnitProperty_ScheduledFileRegion, 

            kAudioUnitScope_Global, 0,&rgn, sizeof(rgn)), "kAudioUnitProperty_ScheduledFileRegion");

        // prime the fp AU with default values

    UInt32 defaultVal = 0;

    XThrowIfError (au.SetProperty (kAudioUnitProperty_ScheduledFilePrime, 

            kAudioUnitScope_Global, 0, &defaultVal, sizeof(defaultVal)), "kAudioUnitProperty_ScheduledFilePrime");

        // tell the fp AU when to start playing (this ts is in the AU's render time stamps; -1 means next render cycle)

    AudioTimeStamp startTime;

    memset (&startTime, 0, sizeof(startTime));

    startTime.mFlags = kAudioTimeStampSampleTimeValid;

    startTime.mSampleTime = -1;

    XThrowIfError (au.SetProperty(kAudioUnitProperty_ScheduleStartTimeStamp, 

            kAudioUnitScope_Global, 0, &startTime, sizeof(startTime)), "kAudioUnitProperty_ScheduleStartTimeStamp");

    return fileDuration;

}

void MakeSimpleGraph (AUGraph &theGraph, CAAudioUnit &fileAU, CAStreamBasicDescription &fileFormat, AudioFileID audioFile)

{

    XThrowIfError (NewAUGraph (&theGraph), "NewAUGraph");

    CAComponentDescription cd;

    // output node

    cd.componentType = kAudioUnitType_Output;

    cd.componentSubType = kAudioUnitSubType_DefaultOutput;

    cd.componentManufacturer = kAudioUnitManufacturer_Apple;

    AUNode outputNode;

    XThrowIfError (AUGraphAddNode (theGraph, &cd, &outputNode), "AUGraphAddNode");

    // file AU node

    AUNode fileNode;

    cd.componentType = kAudioUnitType_Generator;

    cd.componentSubType = kAudioUnitSubType_AudioFilePlayer;

    XThrowIfError (AUGraphAddNode (theGraph, &cd, &fileNode), "AUGraphAddNode");

    // connect & setup

    XThrowIfError (AUGraphOpen (theGraph), "AUGraphOpen");

    // install overload listener to detect when something is wrong

    AudioUnit anAU;

    XThrowIfError (AUGraphNodeInfo(theGraph, fileNode, NULL, &anAU), "AUGraphNodeInfo");

    fileAU = CAAudioUnit (fileNode, anAU);

// prepare the file AU for playback

// set its output channels

    XThrowIfError (fileAU.SetNumberChannels (kAudioUnitScope_Output, 0, fileFormat.NumberChannels()), "SetNumberChannels");

// set the output sample rate of the file AU to be the same as the file:

    XThrowIfError (fileAU.SetSampleRate (kAudioUnitScope_Output, 0, fileFormat.mSampleRate), "SetSampleRate");

// load in the file 

    XThrowIfError (fileAU.SetProperty(kAudioUnitProperty_ScheduledFileIDs, 

                        kAudioUnitScope_Global, 0, &audioFile, sizeof(audioFile)), "SetScheduleFile");

    XThrowIfError (AUGraphConnectNodeInput (theGraph, fileNode, 0, outputNode, 0), "AUGraphConnectNodeInput");

// AT this point we make sure we have the file player AU initialized

// this also propogates the output format of the AU to the output unit

    XThrowIfError (AUGraphInitialize (theGraph), "AUGraphInitialize");

    // workaround a race condition in the file player AU

    usleep (10 * 1000);

// if we have a surround file, then we should try to tell the output AU what the order of the channels will be

    if (fileFormat.NumberChannels() > 2) {

        UInt32 layoutSize = 0;

        OSStatus err;

        XThrowIfError (err = AudioFileGetPropertyInfo (audioFile, kAudioFilePropertyChannelLayout, &layoutSize, NULL),

                                "kAudioFilePropertyChannelLayout");

        if (!err && layoutSize) {

            char* layout = new char[layoutSize];

            err = AudioFileGetProperty(audioFile, kAudioFilePropertyChannelLayout, &layoutSize, layout);

            XThrowIfError (err, "Get Layout From AudioFile");

            // ok, now get the output AU and set its layout

            XThrowIfError (AUGraphNodeInfo(theGraph, outputNode, NULL, &anAU), "AUGraphNodeInfo");

            err = AudioUnitSetProperty (anAU, kAudioUnitProperty_AudioChannelLayout, 

                            kAudioUnitScope_Input, 0, layout, layoutSize);

            XThrowIfError (err, "kAudioUnitProperty_AudioChannelLayout");

            delete [] layout;

        }

    }

}