{ 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_16-0-4-1.glsl";
      sha256 = "1ik99yb424r6qzq4j9pp244yx6c6sq6khqrhv9n6qv4ndi1h2qmq";

      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;
    };
  };

  pitchcontrol = (pkgs.stdenvNoCC.mkDerivation rec {
    name = "pitchcontrol.lua";
    scriptName = name;

    src = pkgs.fetchFromGitHub {
      owner = "FichteFoll";
      repo = "mpv-scripts";
      rev = "28ce548e82460b1ca40d3d0149faffff97c874a0";
      sha256 = "159bbkk0jj25msqyg0wq5w152g6rvm325nzg0b68qzsszz73bw5p";
    };

    installPhase = ''
      mkdir -p $out/share/mpv/scripts/
      cp pitchcontrol.lua $out/share/mpv/scripts
    '';

    meta.license = lib.licenses.isc;
  });

  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";
    };

    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";
    };

    profiles = {
      musicvideo = {
        lavfi-complex = "[aid1]asplit=4[ao][a1][a2][a3];[a1]avectorscope=m=lissajous:s=640x600:draw=dot:r=25[avectorscope];[a2]aresample=44100,showwaves=s=1280x600:mode=p2p:colors=red|lightgreen:r=25[showwaves];[a3]showcqt=s=1920x600:axis=0:axis_h=0:r=25[showcqt];[showwaves][avectorscope]hstack=shortest=1[top];[top][showcqt]vstack=shortest=1,fps=25[vo]";
        alpha = false;
      };

      musicvideo-1080 = {
        lavfi-complex = "[aid1]asplit=4[ao][a1][a2][a3];[a1]avectorscope=m=lissajous:s=640x540:draw=dot:r=25[avectorscope];[a2]aresample=44100,showwaves=s=1280x540:mode=p2p:colors=red|lightgreen:r=25[showwaves];[a3]showcqt=s=1920x540:axis=0:axis_h=0:r=25[showcqt];[showwaves][avectorscope]hstack=shortest=1[top];[top][showcqt]vstack=shortest=1,fps=25[vo]";
        alpha = false;
      };

      musicvideo-c64 = {
        lavfi-complex = "[aid1]channelsplit=4.0[mono][c1][c2][c3];[mono]channelmap=mono,asplit=2[ao][a2];[c1][c2][c3]join=inputs=3:channel_layout=3.0[a1];[a1]aresample=44100,showwaves=s=1920x600:mode=p2p:colors=red|lightgreen|yellow:split_channels=1:r=25[showwaves];[a2]showcqt=s=1920x600:axis=0:axis_h=0:r=25[showcqt];[showwaves][showcqt]vstack=shortest=1,fps=25,format=rgba[vo]";
        alpha = false;
      };

      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;
      };

      # https://github.com/mpv-player/mpv/issues/4418#issuecomment-368272929
      clear-speed.af-add = "scaletempo=stride=28:overlap=.9:search=25";
    };

    scripts = [
      pitchcontrol
    ];
  };

  # 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
  '';
}