using System.ComponentModel;
using System.Diagnostics;
using System.Text;

namespace NadekoBot.Services;

public class YtdlOperation
{
    private readonly string _baseArgString;

    public YtdlOperation(string baseArgString)
        => _baseArgString = baseArgString;

    private Process CreateProcess(string[] args)
    {
        args = args.Map(arg => arg.Replace("\"", ""));
        return new()
        {
            StartInfo = new()
            {
                FileName = "youtube-dl",
                Arguments = string.Format(_baseArgString, args),
                UseShellExecute = false,
                RedirectStandardError = true,
                RedirectStandardOutput = true,
                StandardOutputEncoding = Encoding.UTF8,
                StandardErrorEncoding = Encoding.UTF8,
                CreateNoWindow = true,
            },
        };
    }
        
    public async Task<string> GetDataAsync(params string[] args)
    {
        try
        {
            using var process = CreateProcess(args);

            Log.Debug($"Executing {process.StartInfo.FileName} {process.StartInfo.Arguments}");
            process.Start();

            var str = await process.StandardOutput.ReadToEndAsync().ConfigureAwait(false);
            var err = await process.StandardError.ReadToEndAsync().ConfigureAwait(false);
            if (!string.IsNullOrEmpty(err))
                Log.Warning("YTDL warning: {YtdlWarning}", err);

            return str;
        }
        catch (Win32Exception)
        {
            Log.Error("youtube-dl is likely not installed. " +
                      "Please install it before running the command again");
            return default;
        }
        catch (Exception ex)
        {
            Log.Error(ex , "Exception running youtube-dl: {ErrorMessage}", ex.Message);
            return default;
        }
    }

    public async IAsyncEnumerable<string> EnumerateDataAsync(params string[] args)
    {
        using var process = CreateProcess(args);

        Log.Debug($"Executing {process.StartInfo.FileName} {process.StartInfo.Arguments}");
        process.Start();
            
        string line;
        while((line = await process.StandardOutput.ReadLineAsync()) != null)
            yield return line;
    }
}