FFMpegCore/FFMpegCore/FFMpeg/Arguments/MetaDataArgument.cs

namespace FFMpegCore.Arguments;

public class MetaDataArgument : IInputArgument, IDynamicArgument
{
    private readonly string _metaDataContent;
    private readonly string _tempFileName = Path.Combine(GlobalFFOptions.Current.TemporaryFilesFolder, $"metadata_{Guid.NewGuid()}.txt");

    public MetaDataArgument(string metaDataContent)
    {
        _metaDataContent = metaDataContent;
    }

    public string GetText(IEnumerable<IArgument>? arguments)
    {
        arguments ??= Enumerable.Empty<IArgument>();

        var index = arguments
            .TakeWhile(x => x != this)
            .OfType<IInputArgument>()
            .Count();

        return $"-i \"{_tempFileName}\" -map_metadata {index}";
    }

    public string Text => GetText(null);

    public Task During(CancellationToken cancellationToken = default)
    {
        return Task.CompletedTask;
    }

    public void Pre()
    {
        File.WriteAllText(_tempFileName, _metaDataContent);
    }

    public void Post()
    {
        File.Delete(_tempFileName);
    }
}