/*
  ==============================================================================

   This file is part of the JUCE framework.
   Copyright (c) Raw Material Software Limited

   JUCE is an open source framework subject to commercial or open source
   licensing.

   By downloading, installing, or using the JUCE framework, or combining the
   JUCE framework with any other source code, object code, content or any other
   copyrightable work, you agree to the terms of the JUCE End User Licence
   Agreement, and all incorporated terms including the JUCE Privacy Policy and
   the JUCE Website Terms of Service, as applicable, which will bind you. If you
   do not agree to the terms of these agreements, we will not license the JUCE
   framework to you, and you must discontinue the installation or download
   process and cease use of the JUCE framework.

   JUCE End User Licence Agreement: https://juce.com/legal/juce-8-licence/
   JUCE Privacy Policy: https://juce.com/juce-privacy-policy
   JUCE Website Terms of Service: https://juce.com/juce-website-terms-of-service/

   Or:

   You may also use this code under the terms of the AGPLv3:
   https://www.gnu.org/licenses/agpl-3.0.en.html

   THE JUCE FRAMEWORK IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL
   WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING WARRANTY OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

namespace CDReaderHelpers
{
    inline const XmlElement* getElementForKey (const XmlElement& xml, const String& key)
    {
        for (auto* child : xml.getChildWithTagNameIterator ("key"))
            if (child->getAllSubText().trim() == key)
                return child->getNextElement();

        return nullptr;
    }

    static int getIntValueForKey (const XmlElement& xml, const String& key, int defaultValue = -1)
    {
        const XmlElement* const block = getElementForKey (xml, key);
        return block != nullptr ? block->getAllSubText().trim().getIntValue() : defaultValue;
    }

    // Get the track offsets for a CD given an XmlElement representing its TOC.Plist.
    // Returns NULL on success, otherwise a const char* representing an error.
    static const char* getTrackOffsets (XmlDocument& xmlDocument, Array<int>& offsets)
    {
        const std::unique_ptr<XmlElement> xml (xmlDocument.getDocumentElement());
        if (xml == nullptr)
            return "Couldn't parse XML in file";

        const XmlElement* const dict = xml->getChildByName ("dict");
        if (dict == nullptr)
            return "Couldn't get top level dictionary";

        const XmlElement* const sessions = getElementForKey (*dict, "Sessions");
        if (sessions == nullptr)
            return "Couldn't find sessions key";

        const XmlElement* const session = sessions->getFirstChildElement();
        if (session == nullptr)
            return "Couldn't find first session";

        const int leadOut = getIntValueForKey (*session, "Leadout Block");
        if (leadOut < 0)
            return "Couldn't find Leadout Block";

        const XmlElement* const trackArray = getElementForKey (*session, "Track Array");
        if (trackArray == nullptr)
            return "Couldn't find Track Array";

        for (auto* track : trackArray->getChildIterator())
        {
            const int trackValue = getIntValueForKey (*track, "Start Block");
            if (trackValue < 0)
                return "Couldn't find Start Block in the track";

            offsets.add (trackValue * AudioCDReader::samplesPerFrame - 88200);
        }

        offsets.add (leadOut * AudioCDReader::samplesPerFrame - 88200);
        return nullptr;
    }

    static void findDevices (Array<File>& cds)
    {
        File volumes ("/Volumes");
        volumes.findChildFiles (cds, File::findDirectories, false);

        for (int i = cds.size(); --i >= 0;)
            if (! cds.getReference (i).getChildFile (".TOC.plist").exists())
                cds.remove (i);
    }

    struct TrackSorter
    {
        static int getCDTrackNumber (const File& file)
        {
            return file.getFileName().initialSectionContainingOnly ("0123456789").getIntValue();
        }

        static int compareElements (const File& first, const File& second)
        {
            const int firstTrack  = getCDTrackNumber (first);
            const int secondTrack = getCDTrackNumber (second);

            jassert (firstTrack > 0 && secondTrack > 0);

            return firstTrack - secondTrack;
        }
    };
}

//==============================================================================
StringArray AudioCDReader::getAvailableCDNames()
{
    Array<File> cds;
    CDReaderHelpers::findDevices (cds);

    StringArray names;

    for (int i = 0; i < cds.size(); ++i)
        names.add (cds.getReference (i).getFileName());

    return names;
}

AudioCDReader* AudioCDReader::createReaderForCD (const int index)
{
    Array<File> cds;
    CDReaderHelpers::findDevices (cds);

    if (cds[index].exists())
        return new AudioCDReader (cds[index]);

    return nullptr;
}

AudioCDReader::AudioCDReader (const File& volume)
   : AudioFormatReader (nullptr, "CD Audio"),
     volumeDir (volume),
     currentReaderTrack (-1)
{
     sampleRate = 44100.0;
     bitsPerSample = 16;
     numChannels = 2;
     usesFloatingPointData = false;

     refreshTrackLengths();
}

AudioCDReader::~AudioCDReader()
{
}

void AudioCDReader::refreshTrackLengths()
{
    tracks.clear();
    trackStartSamples.clear();
    lengthInSamples = 0;

    volumeDir.findChildFiles (tracks, File::findFiles | File::ignoreHiddenFiles, false, "*.aiff");

    CDReaderHelpers::TrackSorter sorter;
    tracks.sort (sorter);

    const File toc (volumeDir.getChildFile (".TOC.plist"));

    if (toc.exists())
    {
        XmlDocument doc (toc);
        [[maybe_unused]] const char* error = CDReaderHelpers::getTrackOffsets (doc, trackStartSamples);

        lengthInSamples = trackStartSamples.getLast() - trackStartSamples.getFirst();
    }
}

bool AudioCDReader::readSamples (int* const* destSamples, int numDestChannels, int startOffsetInDestBuffer,
                                 int64 startSampleInFile, int numSamples)
{
    while (numSamples > 0)
    {
        int track = -1;

        for (int i = 0; i < trackStartSamples.size() - 1; ++i)
        {
            if (startSampleInFile < trackStartSamples.getUnchecked (i + 1))
            {
                track = i;
                break;
            }
        }

        if (track < 0)
            return false;

        if (track != currentReaderTrack)
        {
            reader = nullptr;

            if (auto in = tracks [track].createInputStream())
            {
                BufferedInputStream* const bin = new BufferedInputStream (in.release(), 65536, true);

                AiffAudioFormat format;
                reader.reset (format.createReaderFor (bin, true));

                if (reader == nullptr)
                    currentReaderTrack = -1;
                else
                    currentReaderTrack = track;
            }
        }

        if (reader == nullptr)
            return false;

        const int startPos = (int) (startSampleInFile - trackStartSamples.getUnchecked (track));
        const int numAvailable = (int) jmin ((int64) numSamples, reader->lengthInSamples - startPos);

        reader->readSamples (destSamples, numDestChannels, startOffsetInDestBuffer, startPos, numAvailable);

        numSamples -= numAvailable;
        startSampleInFile += numAvailable;
    }

    return true;
}

bool AudioCDReader::isCDStillPresent() const
{
    return volumeDir.exists();
}

void AudioCDReader::ejectDisk()
{
    JUCE_AUTORELEASEPOOL
    {
        [[NSWorkspace sharedWorkspace] unmountAndEjectDeviceAtPath: juceStringToNS (volumeDir.getFullPathName())];
    }
}

bool AudioCDReader::isTrackAudio (int trackNum) const
{
    return tracks [trackNum].hasFileExtension (".aiff");
}

void AudioCDReader::enableIndexScanning (bool)
{
    // any way to do this on a Mac??
}

int AudioCDReader::getLastIndex() const
{
    return 0;
}

Array<int> AudioCDReader::findIndexesInTrack (const int /*trackNumber*/)
{
    return {};
}

} // namespace juce