using System.Diagnostics;

namespace Encoder.Lib;

public class DetectWorker
{
    private readonly ProcessStartInfo startInfo;
    public string? MaxVolume { get; private set; }
    public string? MeanVolume { get; private set; }

    public DetectWorker(string workingDirectory, string inputFile, string encodeParam)
    {
        var arguments = $"-y -i \"{inputFile}\" {encodeParam} -f null -";
        this.startInfo = new ProcessStartInfo()
        {
            FileName = "ffmpeg",
            WorkingDirectory = workingDirectory,
            Arguments = arguments,
        };
        this.MeanVolume = null;
        this.MaxVolume = null;
    }

    public async ValueTask<int> Run()
    {
        try
        {
            Console.WriteLine($"{this.startInfo.FileName} {this.startInfo.Arguments}");
            using Process process = new Process();
            process.StartInfo = this.startInfo;
            process.StartInfo.UseShellExecute = false;
            process.StartInfo.RedirectStandardOutput = true;
            process.StartInfo.RedirectStandardError = true;
            process.StartInfo.CreateNoWindow = true;

            var result = process.Start();

            if (!result)
            {
                throw new FileNotFoundException();
            }

            var str = await process.StandardError.ReadToEndAsync().ConfigureAwait(false);
            await process.WaitForExitAsync().ConfigureAwait(false);

            // Console.WriteLine(str);
            var maxVolumeLine = str.Split('\n').FirstOrDefault(line => line.Contains("max_volume"));
            this.MaxVolume = maxVolumeLine?.Split(':').Skip(1).FirstOrDefault()?.Trim().Replace(" ", "");
            var meanVolumeLine = str.Split('\n').FirstOrDefault(line => line.Contains("mean_volume"));
            this.MeanVolume = meanVolumeLine?.Split(':').Skip(1).FirstOrDefault()?.Trim().Replace(" ", "");

            return process.ExitCode;
        }
        catch (Exception err)
        {
            Console.WriteLine(err);
            return -1;
        }
    }
}