SoundFontParameters.fromReader constructor

SoundFontParameters.fromReader(BinaryReader reader)

Implementation

factory SoundFontParameters.fromReader(BinaryReader reader)
{
    String chunkId = reader.readFourCC();

    if (chunkId != "LIST")
    {
        throw "The LIST chunk was not found.";
    }

    int end = reader.readInt32();
    end += reader.pos;

    var listType = reader.readFourCC();

    if (listType != "pdta")
    {
        throw "The type of the LIST chunk must be 'pdta', but was '$listType'.";
    }

    List<PresetInfo> presetInfos = [];
    List<ZoneInfo> presetBag = [];
    List<Generator> presetGenerators = [];
    List<InstrumentInfo> instrumentInfos = [];
    List<ZoneInfo> instrumentBag = [];
    List<Generator> instrumentGenerators = [];
    List<SampleHeader> sampleHeaders = [];

    while (reader.pos < end)
    {
        String id = reader.readFourCC();
        int size = reader.readInt32();

        switch (id)
        {
            case "phdr":
                presetInfos = PresetInfo.readFromChunk(reader, size);
                break;
            case "pbag":
                presetBag = ZoneInfo.readFromChunk(reader, size);
                break;
            case "pmod":
                Modulator.discardData(reader, size);
                break;
            case "pgen":
                presetGenerators = Generator.readFromChunk(reader, size);
                break;
            case "inst":
                instrumentInfos = InstrumentInfo.readFromChunk(reader, size);
                break;
            case "ibag":
                instrumentBag = ZoneInfo.readFromChunk(reader, size);
                break;
            case "imod":
                Modulator.discardData(reader, size);
                break;
            case "igen":
                instrumentGenerators = Generator.readFromChunk(reader, size);
                break;
            case "shdr":
                sampleHeaders = SampleHeader.readFromChunk(reader, size);
                break;
            default:
                throw "The INFO list contains an unknown ID '$id'.";
        }
    }

    if (presetInfos.isEmpty) throw "The PHDR sub-chunk was not found.";
    if (presetBag.isEmpty) throw "The PBAG sub-chunk was not found.";
    if (presetGenerators.isEmpty) throw "The PGEN sub-chunk was not found.";
    if (instrumentInfos.isEmpty) throw "The INST sub-chunk was not found.";
    if (instrumentBag.isEmpty) throw "The IBAG sub-chunk was not found.";
    if (instrumentGenerators.isEmpty) throw "The IGEN sub-chunk was not found.";
    if (sampleHeaders.isEmpty) throw "The SHDR sub-chunk was not found.";

    List<Zone> instrumentZones = Zone.create(instrumentBag, instrumentGenerators);

    List<Instrument> instruments = Instrument.create(instrumentInfos, instrumentZones, sampleHeaders);

    List<Zone> presetZones = Zone.create(presetBag, presetGenerators);

    List<Preset> presets = Preset.create(presetInfos, presetZones, instruments);

    return SoundFontParameters(
      sampleHeaders: sampleHeaders,
      presets: presets,
      instruments: instruments
    );
}