{ config, pkgs, lib, ... }:

with lib;

let

  # Lassulus streaming setup
  # -------------------------
  # ffmpeg \
  #   -f pulse \
  #   -i default \
  #   -vaapi_device /dev/dri/renderD128 \
  #   -f x11grab \
  #   -video_size 1366x768 \
  #   -i :0 \
  #   -vf 'hwupload,scale_vaapi=format=nv12' \
  #   -c:v h264_vaapi \
  #   -c:a aac \
  #   -b:a 96k \
  #   -af "highpass=f=200, lowpass=f=3000" \
  #   -qp 30 \
  #   -f flv \
  #   rtmp://lassul.us:1935/stream/nixos \
  #   ./rc3-output-$(date +%d%H%M%S).mp4
  #
  # Dann abspielen mit :
  # mpv rtmp://lassul.us:1935/stream/nixos

  cfg = config.programs.custom.video;

  # show keyboard input on desktop for screencasts
  screenKey = pkgs.symlinkJoin {
    name = "screen-keys";
    paths =
      let
        screenKeyScript = { position ? "bottom", size ? "small", ... }:
          pkgs.writeShellScriptBin "screenkeys-${position}-${size}" # sh
            ''
              ${pkgs.screenkey}/bin/screenkey \
                                --no-detach \
                                --bg-color '#fdf6e3' \
                                --font-color '#073642' \
                                -p ${position} \
                                -s ${size} \
                                "$@"
            '';
      in
      lib.flatten (lib.flip map [ "large" "small" "medium" ] (size:
        lib.flip map [ "top" "center" "bottom" ]
          (position: screenKeyScript { inherit size position; })));
  };


  mpvReview =
    let
      moveToDir = key: dir: pkgs.writeText "move-with-${key}.lua" ''
        tmp_dir = "${dir}"

        function move_current_track_${key}()
          track = mp.get_property("path")
          os.execute("mkdir -p '" .. tmp_dir .. "'")
          os.execute("mv '" .. track .. "' '" .. tmp_dir .. "'")
          print("moved '" .. track .. "' to " .. tmp_dir)
        end

        mp.add_key_binding("${key}", "move_current_track_${key}", move_current_track_${key})
      '';
      delete = moveToDir "D" "./.graveyard";
      good = moveToDir "G" "./.good";
    in
    pkgs.writers.writeDashBin "mpv-review" ''
      exec ${pkgs.mpv}/bin/mpv --no-config --script=${delete} --script=${good} "$@"
    '';


in
{

  options.programs.custom.video.enable = mkEnableOption "enable video tools";

  config = mkIf cfg.enable {
    environment.systemPackages = with pkgs; [
      unstable.youtube-dl
      unstable.yt-dlp
      mplayer
      mpv
      mpvReview


      # to record your screen
      # ---------------------
      simplescreenrecorder
      screenKey

      # to transcode video material
      # ---------------------------
      handbrake
      ffmpeg-full

      # video editing
      # -------------
      openshot-qt

    ];
  };
}