{ config, lib, nixosConfig, pkgs, ... }:
let
  mpv-prescalers = pkgs.fetchFromGitHub {
    owner = "bjin";
    repo = "mpv-prescalers";
    rev = "b37d0f12223720f5ce48e149678162ae0a984176";
    sha256 = "1mmf5827qsyph0wqkyvi7zfng1cskkapngn5hf9073zc61n4398y";

    meta.license = lib.licenses.lgpl3Plus;
  };

  shaders = {
    fsrcnnx_x2 = pkgs.fetchurl {
      url = "https://github.com/igv/FSRCNN-TensorFlow/releases/download/1.1/FSRCNNX_x2_8-0-4-1.glsl";
      sha256 = "03qv0l3b1bznarlv0jpi4gqg1zg3khsw5cp8pmabg73k0xpcwqix";

      meta.license = lib.licenses.mit;
    };

    SSimDownscaler = pkgs.fetchurl {
      url = "https://gist.github.com/igv/36508af3ffc84410fe39761d6969be10/raw/ac09db2c0664150863e85d5a4f9f0106b6443a12/SSimDownscaler.glsl";
      sha256 = "1c3fp6llg0n8zdxadsg6g3kcvhqvikalbc9q61zgwvsx8q3d8rph";

      meta.license = lib.licenses.lgpl3Plus;
    };

    KrigBilateral = pkgs.fetchurl {
      url = "https://gist.github.com/igv/a015fc885d5c22e6891820ad89555637/raw/c471ef6dcbd3c4a977e1c95dc40944ee38fad08a/KrigBilateral.glsl";
      sha256 = "11s0h6i0y3h2nrfp6lax6hzwvjbn93akjr6d61jrmz09zdf1iwmc";

      meta.license = lib.licenses.lgpl3Plus;
    };
  };

  gallery-view = pkgs.fetchFromGitHub {
    owner = "occivink";
    repo = "mpv-gallery-view";
    rev = "5139d346de67e8dbee8c8983777026502d6bc627";
    sha256 = "1xcl31rpb6kp479kil4srkclw9ly565zavr65ary9s8795ygfcrs";

    meta.license = lib.licenses.gpl2;
  };

  cycleShaders = shaders: "cycle-values glsl-shaders ${lib.concatStringsSep " " shaders}";
in
{
  programs.mpv = {
    enable = nixosConfig.sbruder.gui.enable;

    config = {
      # Main application font
      osd-font = "DINW07-Medium"; # not included in repository (unfree)

      # Subtitles
      sub-font = "Gandhi Sans"; # see osd-font
      sub-bold = true;
      sub-font-size = 44;
      sub-use-margins = false;
      sub-border-size = 2;

      # Nicer looking vobsub/PGS subtitles
      sub-gauss = 0.5;
      sub-gray = true;

      # Allow higher volumes
      volume-max = 150;

      # Downmix to stereo by default
      audio-channels = "stereo";

      # Allow seeking in streamed media
      force-seekable = true;

      # Enable hardware decoding when avaliable
      hwdec = "auto-safe";

      # Do not show images only one second
      image-display-duration = "inf";

      # Better quality (but not too high, otherwise too high frame drop)
      profile = "gpu-hq";
      deband = false;
      dither-depth = "auto";

      # Lossless screenshots
      screenshot-format = "png";

      # Use youtube-dl’s format configuration
      ytdl-format = "ytdl";
    };

    bindings = {
      # Audio filter bs2b (for headphones)
      "b" = "af toggle bs2b";

      # Toggle debanding
      "D" = "cycle deband";

      # Variable correction of audio pitch when changing speed
      "k" = "cycle-values audio-pitch-correction no yes";

      # Reverse cycling for audio and video (shift modifier on german keyboard layout)
      "'" = "cycle audio down";
      "-" = "cycle video down";

      # Cycle between audio downmixes
      "c" = "cycle-values audio-channels stereo mono auto";

      # Cycle between smart scalers (and /dev/null = disabled)
      "K" = cycleShaders [
        "${mpv-prescalers}/compute/ravu-lite-r4.hook"
        "${mpv-prescalers}/compute/ravu-lite-r3.hook"
        "${mpv-prescalers}/compute/ravu-lite-r2.hook"
        "/dev/null"
      ];
      "Alt+K" = cycleShaders [
        "${mpv-prescalers}/compute/ravu-zoom-r4-yuv.hook"
        "${mpv-prescalers}/compute/ravu-zoom-r3-yuv.hook"
        "${mpv-prescalers}/compute/ravu-zoom-r2-yuv.hook"
        "/dev/null"
      ];
      "Alt+k" = cycleShaders [
        "${mpv-prescalers}/compute/nnedi3-nns256-win8x4.hook"
        "${mpv-prescalers}/compute/nnedi3-nns128-win8x4.hook"
        "/dev/null"
      ];

      # Toggle pitchcontrol
      "Ctrl+p" = "script-message-to pitchcontrol toggle";

      # more granular panning
      "Alt+left" = "add video-pan-x  0.05";
      "Alt+right" = "add video-pan-x -0.05";
      "Alt+up" = "add video-pan-y  0.05";
      "Alt+down" = "add video-pan-y -0.05";

      # sub-delay for fixing 24 empty frames on blu-ray
      "Alt+z" = "add sub-delay -1";
      "Alt+Z" = "add sub-delay +1";

      # sponsorblock: set segment boundaries
      "alt+g" = "script-binding sponsorblock/set_segment";

      # Exits with error to not mark the video as watched in ytcc
      "Shift+q" = "quit-watch-later 1";
    };

    profiles =
      let
        mkVisualiser = width: height: rate: {
          lavfi-complex = lib.concatStringsSep ";" [
            "[aid1]asplit=4[ao][a1][a2][a3]"
            "[a1]avectorscope=m=lissajous:s=${toString (width / 3)}x${toString (height / 2)}:draw=dot:r=${toString rate}[avectorscope]"
            "[a2]aresample=44100,showwaves=s=${toString (width / 3 * 2)}x${toString (height / 2)}:mode=p2p:colors=red|lightgreen:r=${toString rate}[showwaves]"
            "[a3]showcqt=s=${toString width}x${toString (height / 2)}:axis=0:axis_h=0:r=${toString rate}[showcqt]"
            "[showwaves][avectorscope]hstack=shortest=1[top]"
            "[top][showcqt]vstack=shortest=1,fps=${toString rate}[vo]"
          ];
          alpha = false;
        };
      in
      {
        visualiser = mkVisualiser 1920 1200 30;
        visualiser-1080 = mkVisualiser 1920 1080 30;
        visualiser-60 = mkVisualiser 1920 1080 60;
        visualiser-1080-60 = mkVisualiser 1920 1080 60;

        hqencode = {
          ovc = "libx264";
          ovcopts-add = "crf=18";
          oac = "flac";
          audio-format = "s16";
        };

        lq = {
          scale = "bicubic_fast";
          cscale = "bicubic_fast";
          dscale = "bicubic_fast";
        };

        hq = {
          scale = "ewa_lanczossharp";
          dscale = "mitchell";
          linear-downscaling = "no"; # for KrigBilateral
          cscale = "ewa_lanczos";
          glsl-shader = [
            "${shaders.SSimDownscaler}" # dscale
            "${shaders.KrigBilateral}" # cscale
            "${shaders.fsrcnnx_x2}" # scale
          ];
        };

        interpolate = {
          blend-subtitles = true;
          video-sync = "display-resample";
          interpolation = true;
          tscale = "box";
          tscale-window = "sphinx";
          tscale-radius = 1.0;
          tscale-clamp = 0.0;
        };

        # adapted from https://github.com/mpv-player/mpv/issues/4418#issuecomment-368272929
        clear-speed.af-add = "scaletempo=stride=18:overlap=.6:search=10";
      };

    scripts = with pkgs.mpvScripts; [
      pitchcontrol
      sponsorblock
    ];
  };

  # mpv-gallery-view is not compatible with home-manager’s script injection meachanism
  xdg.configFile."mpv/scripts/gallery-thumbgen-0.lua".source = "${gallery-view}/scripts/gallery-thumbgen.lua";
  xdg.configFile."mpv/scripts/gallery-thumbgen-1.lua".source = "${gallery-view}/scripts/gallery-thumbgen.lua";
  xdg.configFile."mpv/scripts/gallery-thumbgen-2.lua".source = "${gallery-view}/scripts/gallery-thumbgen.lua";
  xdg.configFile."mpv/scripts/gallery-thumbgen-3.lua".source = "${gallery-view}/scripts/gallery-thumbgen.lua";
  xdg.configFile."mpv/scripts/lib/gallery.lua".source = "${gallery-view}/scripts/lib/gallery.lua";
  xdg.configFile."mpv/scripts/playlist-view.lua".source = "${gallery-view}/scripts/playlist-view.lua";
  xdg.configFile."mpv/script-opts/playlist_view.conf".text = ''
    thumbs_dir=${config.xdg.cacheHome}/thumbnails/mpv
  '';
  home.file."${config.xdg.cacheHome}/thumbnails/mpv/.create".text = "";

  xdg.configFile."mpv/script-opts/stats.conf".text = ''
    font=DINW07-Regular
    font_mono=DINW07-Regular
    font_size=10
    redraw_delay=0.25
  '';
}