nix-configs/modules/desktop/audio.nix

{
  pkgs,
  config,
  lib,
  ...
}:
with lib;
let
  cfg = config.xyno.desktop.audio;
  json = pkgs.formats.json { };
  toFloat = builtins.fromJSON;
  readFilterTxt =
    text:
    let
      lines = splitString "\n" text;
      consumeLine =
        line:
        let
          parts = splitString " " line;
          content = foldl (
            props: str:
            if props.lastNode == "Filter" then
              props
              // {
                nr = toInt (removeSuffix ":" str);
                lastNode = str;
              }
            else if props.lastNode == "Preamp:" then
              props
              // {
                nr = 0;
                gain = toFloat str;
                label = "HSC";
                lastNode = str;
                freq = 0;
                q = 1.0;
              }
            else if props.lastNode == "ON" then
              props
              // {
                label = str;
                lastNode = str;
              }
            else if props.lastNode == "Fc" then
              props
              // {
                freq = toInt str;
                lastNode = str;
              }
            else if props.lastNode == "Gain" then
              props
              // {
                gain = toFloat str;
                lastNode = str;
              }
            else if props.lastNode == "Q" then
              props
              // {
                q = toFloat str;
                lastNode = str;
              }
            else

              props // { lastNode = str; }
          ) { lastNode = null; } parts;
        in
        content;
    in
    filter (x: x ? nr) (map consumeLine lines);
  genFilterGraph = filters: {
    nodes = (
      map (filter: {
        type = "builtin";
        name = "eq_band_${toString (filter.nr + 1)}";
        label =
          if filter.label == "HSC" then
            "bq_highshelf"
          else if filter.label == "LSC" then
            "bq_lowshelf"
          else
            "bq_peaking";
        control = {
          Freq = filter.freq;
          Q = filter.q;
          Gain = filter.gain;
        };

      }) filters
    );
    links = map (x: {
      output = "eq_band_${toString x}:Out";
      input = "eq_band_${toString (x + 1)}:In";
    }) (range 1 ((builtins.length filters) - 1));
  };
  genfilterChain =
    cfg':
    json.generate "filter-chain.json" (
      recursiveUpdate {
        "node.description" = cfg'.displayName;
        "media.name" = cfg'.displayName;
        "filter.graph" = genFilterGraph (readFilterTxt cfg'.filterText);
        "audio.channels" = 2;
        "audio.position" = [
          "FL"
          "FR"
        ];
        "capture.props" = {
          "node.name" = "effect_input.${cfg'.internalName}";
          "media.class" = "Audio/Sink";
        };
        "playback.props" = {
          "node.name" = "effect_output.${cfg'.internalName}";
          "node.passive" = true;
          "target.object" = cfg'.hwAddr;
        };
      } cfg'.extraConfig
    );
  eqPkg =
    cfg':
    (pkgs.writeTextDir "share/wireplumber/wireplumber.conf.d/99-${cfg'.internalName}.conf" ''
      node.software-dsp.rules = [
        {
          matches = [{ node.name = "${cfg'.hwAddr}" }]
          actions = {
            create-filter = {
              filter-path = "${genfilterChain cfg'}"
              hide-parent = ${boolToString cfg'.hideParent}
            }
          }
        }
      ]

      wireplumber.profiles = {
        main = { node.software-dsp = "required" }
      }
    '')
    // {
      passthru.requiredLv2Packages = with pkgs; [
        lsp-plugins
        bankstown-lv2
      ];

    };

  eqSubmodule =
    { name, ... }:
    {
      options = {
        internalName = mkOption {
          type = types.str;
          default = name;
          internal = true;
        };
        displayName = mkOption { type = types.str; };
        hwAddr = mkOption { type = types.str; };
        filterText = mkOption { type = types.str; };
        hideParent = mkOption {
          type = types.bool;
          default = true;
        };
        extraConfig = mkOption {
          type = types.attrsOf types.anything;
          default = { };
        };
      };
    };

in
{
  options.xyno.desktop.audio.enable = mkEnableOption "enable pipewire and stuff";
  options.xyno.desktop.audio.eq = mkOption {
    type = types.attrsOf (types.submodule eqSubmodule);
    default = { };
  };
  config = mkIf cfg.enable {
    # https://github.com/jaakkopasanen/AutoEq/blob/master/results/oratory1990/in-ear/Shure%20SE215/Shure%20SE215%20ParametricEQ.txt
    xyno.desktop.audio.eq.se215 = {
      displayName = "Shure SE215";
      hwAddr = "alsa_output.usb-Synaptics_CX31993_384Khz_HIFI_AUDIO-00.analog-stereo";
      # hideParent = false;
      extraConfig."capture.props"."device.icon-name" = "audio-headphones";
      filterText = ''
        Preamp: -5.7 dB
        Filter 1: ON LSC Fc 105 Hz Gain 0.3 dB Q 0.70
        Filter 2: ON PK Fc 174 Hz Gain -4.6 dB Q 0.68
        Filter 3: ON PK Fc 811 Hz Gain 3.1 dB Q 1.42
        Filter 4: ON PK Fc 3430 Hz Gain 3.8 dB Q 4.37
        Filter 5: ON PK Fc 6943 Hz Gain 5.4 dB Q 2.76
        Filter 6: ON HSC Fc 10000 Hz Gain 3.8 dB Q 0.70
        Filter 7: ON PK Fc 5725 Hz Gain 8.1 dB Q 1.13
        Filter 8: ON PK Fc 5056 Hz Gain -10.9 dB Q 2.93
        Filter 9: ON PK Fc 7269 Hz Gain -6.3 dB Q 3.47
        Filter 10: ON PK Fc 2278 Hz Gain -2.1 dB Q 2.94
      '';
    };
    services.pipewire = {
      enable = true;
      # raopOpenFirewall = true; # airplay
      pulse.enable = true;
      extraConfig.pipewire = {
        "9-clock-allow-higher" = {
          "context.properties" = {
            "default.clock.allowed-rates" = [
              "44100"
              "48000"
              "88200"
              "96000"
              "176400"
              "192000"
            ];
          };
        };
        # "10-raop-discover" = {
        #   "context.modules" = [
        #     {
        #       name = "libpipewire-module-raop-discover";
        #       args = { };
        #     }
        #   ];
        # };
      };
      extraConfig.pipewire-pulse = {
        "10-zeroconf" = {
          "pulse.cmd" = [
            {
              cmd = "load-module";
              args = "module-zeroconf-discover";
            }
          ];
        };
      };
      wireplumber.extraConfig."98-bluetooth"."wireplumber.settings"."bluetooth.autoswitch-to-headset-profile" =
        false;
      wireplumber.configPackages = mapAttrsToList (n: v: eqPkg v) cfg.eq;
    };

  };
}