nixos/autorandr: refactor

The autorandr module now provides options to set hooks declaratively
It also provides options to set profiles declaratively.

nixos/doc/manual/from_md/release-notes/rl-2205.section.xml

@@ -699,6 +699,12 @@
           warning.
         </para>
       </listitem>
+      <listitem>
+        <para>
+          <literal>services.autorandr</literal> now allows for adding
+          hooks and profiles declaratively.
+        </para>
+      </listitem>
     </itemizedlist>
   </section>
 </section>

nixos/doc/manual/release-notes/rl-2205.section.md

@@ -237,4 +237,6 @@ In addition to numerous new and upgraded packages, this release has the followin
   Reason is that the old name has been deprecated upstream.
   Using the old option name will still work, but produce a warning.
 
+- `services.autorandr` now allows for adding hooks and profiles declaratively.
+
 <!-- To avoid merge conflicts, consider adding your item at an arbitrary place in the list instead. -->

nixos/modules/services/misc/autorandr.nix

@@ -5,6 +5,243 @@ with lib;
 let
 
   cfg = config.services.autorandr;
+  hookType = types.lines;
+
+  matrixOf = n: m: elemType:
+  mkOptionType rec {
+    name = "matrixOf";
+    description =
+      "${toString n}×${toString m} matrix of ${elemType.description}s";
+    check = xss:
+      let listOfSize = l: xs: isList xs && length xs == l;
+      in listOfSize n xss
+      && all (xs: listOfSize m xs && all elemType.check xs) xss;
+    merge = mergeOneOption;
+    getSubOptions = prefix: elemType.getSubOptions (prefix ++ [ "*" "*" ]);
+    getSubModules = elemType.getSubModules;
+    substSubModules = mod: matrixOf n m (elemType.substSubModules mod);
+    functor = (defaultFunctor name) // { wrapped = elemType; };
+  };
+
+  profileModule = types.submodule {
+    options = {
+      fingerprint = mkOption {
+        type = types.attrsOf types.str;
+        description = ''
+          Output name to EDID mapping.
+          Use <code>autorandr --fingerprint</code> to get current setup values.
+        '';
+        default = { };
+      };
+
+      config = mkOption {
+        type = types.attrsOf configModule;
+        description = "Per output profile configuration.";
+        default = { };
+      };
+
+      hooks = mkOption {
+        type = hooksModule;
+        description = "Profile hook scripts.";
+        default = { };
+      };
+    };
+  };
+
+  configModule = types.submodule {
+    options = {
+      enable = mkOption {
+        type = types.bool;
+        description = "Whether to enable the output.";
+        default = true;
+      };
+
+      crtc = mkOption {
+        type = types.nullOr types.ints.unsigned;
+        description = "Output video display controller.";
+        default = null;
+        example = 0;
+      };
+
+      primary = mkOption {
+        type = types.bool;
+        description = "Whether output should be marked as primary";
+        default = false;
+      };
+
+      position = mkOption {
+        type = types.str;
+        description = "Output position";
+        default = "";
+        example = "5760x0";
+      };
+
+      mode = mkOption {
+        type = types.str;
+        description = "Output resolution.";
+        default = "";
+        example = "3840x2160";
+      };
+
+      rate = mkOption {
+        type = types.str;
+        description = "Output framerate.";
+        default = "";
+        example = "60.00";
+      };
+
+      gamma = mkOption {
+        type = types.str;
+        description = "Output gamma configuration.";
+        default = "";
+        example = "1.0:0.909:0.833";
+      };
+
+      rotate = mkOption {
+        type = types.nullOr (types.enum [ "normal" "left" "right" "inverted" ]);
+        description = "Output rotate configuration.";
+        default = null;
+        example = "left";
+      };
+
+      transform = mkOption {
+        type = types.nullOr (matrixOf 3 3 types.float);
+        default = null;
+        example = literalExpression ''
+          [
+            [ 0.6 0.0 0.0 ]
+            [ 0.0 0.6 0.0 ]
+            [ 0.0 0.0 1.0 ]
+          ]
+        '';
+        description = ''
+          Refer to
+          <citerefentry>
+            <refentrytitle>xrandr</refentrytitle>
+            <manvolnum>1</manvolnum>
+          </citerefentry>
+          for the documentation of the transform matrix.
+        '';
+      };
+
+      dpi = mkOption {
+        type = types.nullOr types.ints.positive;
+        description = "Output DPI configuration.";
+        default = null;
+        example = 96;
+      };
+
+      scale = mkOption {
+        type = types.nullOr (types.submodule {
+          options = {
+            method = mkOption {
+              type = types.enum [ "factor" "pixel" ];
+              description = "Output scaling method.";
+              default = "factor";
+              example = "pixel";
+            };
+
+            x = mkOption {
+              type = types.either types.float types.ints.positive;
+              description = "Horizontal scaling factor/pixels.";
+            };
+
+            y = mkOption {
+              type = types.either types.float types.ints.positive;
+              description = "Vertical scaling factor/pixels.";
+            };
+          };
+        });
+        description = ''
+          Output scale configuration.
+          </para><para>
+          Either configure by pixels or a scaling factor. When using pixel method the
+          <citerefentry>
+            <refentrytitle>xrandr</refentrytitle>
+            <manvolnum>1</manvolnum>
+          </citerefentry>
+          option
+          <parameter class="command">--scale-from</parameter>
+          will be used; when using factor method the option
+          <parameter class="command">--scale</parameter>
+          will be used.
+          </para><para>
+          This option is a shortcut version of the transform option and they are mutually
+          exclusive.
+        '';
+        default = null;
+        example = literalExpression ''
+          {
+            x = 1.25;
+            y = 1.25;
+          }
+        '';
+      };
+    };
+  };
+
+  hooksModule = types.submodule {
+    options = {
+      postswitch = mkOption {
+        type = types.attrsOf hookType;
+        description = "Postswitch hook executed after mode switch.";
+        default = { };
+      };
+
+      preswitch = mkOption {
+        type = types.attrsOf hookType;
+        description = "Preswitch hook executed before mode switch.";
+        default = { };
+      };
+
+      predetect = mkOption {
+        type = types.attrsOf hookType;
+        description = ''
+          Predetect hook executed before autorandr attempts to run xrandr.
+        '';
+        default = { };
+      };
+    };
+  };
+
+  hookToFile = folder: name: hook:
+    nameValuePair "xdg/autorandr/${folder}/${name}" {
+      source = "${pkgs.writeShellScriptBin "hook" hook}/bin/hook";
+    };
+  profileToFiles = name: profile:
+    with profile;
+    mkMerge ([
+      {
+        "xdg/autorandr/${name}/setup".text = concatStringsSep "\n"
+          (mapAttrsToList fingerprintToString fingerprint);
+        "xdg/autorandr/${name}/config".text =
+          concatStringsSep "\n" (mapAttrsToList configToString profile.config);
+      }
+      (mapAttrs' (hookToFile "${name}/postswitch.d") hooks.postswitch)
+      (mapAttrs' (hookToFile "${name}/preswitch.d") hooks.preswitch)
+      (mapAttrs' (hookToFile "${name}/predetect.d") hooks.predetect)
+    ]);
+  fingerprintToString = name: edid: "${name} ${edid}";
+  configToString = name: config:
+    if config.enable then
+      concatStringsSep "\n" ([ "output ${name}" ]
+        ++ optional (config.position != "") "pos ${config.position}"
+        ++ optional (config.crtc != null) "crtc ${toString config.crtc}"
+        ++ optional config.primary "primary"
+        ++ optional (config.dpi != null) "dpi ${toString config.dpi}"
+        ++ optional (config.gamma != "") "gamma ${config.gamma}"
+        ++ optional (config.mode != "") "mode ${config.mode}"
+        ++ optional (config.rate != "") "rate ${config.rate}"
+        ++ optional (config.rotate != null) "rotate ${config.rotate}"
+        ++ optional (config.transform != null) ("transform "
+          + concatMapStringsSep "," toString (flatten config.transform))
+        ++ optional (config.scale != null)
+        ((if config.scale.method == "factor" then "scale" else "scale-from")
+          + " ${toString config.scale.x}x${toString config.scale.y}"))
+    else ''
+      output ${name}
+      off
+    '';
 
 in {
 
@@ -22,6 +259,67 @@ in {
           for further reference.
         '';
       };
+
+      hooks = mkOption {
+        type = hooksModule;
+        description = "Global hook scripts";
+        default = { };
+        example = ''
+          {
+            postswitch = {
+              "notify-i3" = "''${pkgs.i3}/bin/i3-msg restart";
+              "change-background" = readFile ./change-background.sh;
+              "change-dpi" = '''
+                case "$AUTORANDR_CURRENT_PROFILE" in
+                  default)
+                    DPI=120
+                    ;;
+                  home)
+                    DPI=192
+                    ;;
+                  work)
+                    DPI=144
+                    ;;
+                  *)
+                    echo "Unknown profle: $AUTORANDR_CURRENT_PROFILE"
+                    exit 1
+                esac
+                echo "Xft.dpi: $DPI" | ''${pkgs.xorg.xrdb}/bin/xrdb -merge
+              '''
+            };
+          }
+        '';
+      };
+      profiles = mkOption {
+        type = types.attrsOf profileModule;
+        description = "Autorandr profiles specification.";
+        default = { };
+        example = literalExpression ''
+          {
+            "work" = {
+              fingerprint = {
+                eDP1 = "<EDID>";
+                DP1 = "<EDID>";
+              };
+              config = {
+                eDP1.enable = false;
+                DP1 = {
+                  enable = true;
+                  crtc = 0;
+                  primary = true;
+                  position = "0x0";
+                  mode = "3840x2160";
+                  gamma = "1.0:0.909:0.833";
+                  rate = "60.00";
+                  rotate = "left";
+                };
+              };
+              hooks.postswitch = readFile ./work-postswitch.sh;
+            };
+          }
+        '';
+      };
+
     };
 
   };
@@ -30,7 +328,15 @@ in {
 
     services.udev.packages = [ pkgs.autorandr ];
 
-    environment.systemPackages = [ pkgs.autorandr ];
+    environment = {
+      systemPackages = [ pkgs.autorandr ];
+      etc = mkMerge ([
+        (mapAttrs' (hookToFile "postswitch.d") cfg.hooks.postswitch)
+        (mapAttrs' (hookToFile "preswitch.d") cfg.hooks.preswitch)
+        (mapAttrs' (hookToFile "predetect.d") cfg.hooks.predetect)
+        (mkMerge (mapAttrsToList profileToFiles cfg.profiles))
+      ]);
+    };
 
     systemd.services.autorandr = {
       wantedBy = [ "sleep.target" ];
@@ -48,5 +354,5 @@ in {
 
   };
 
-  meta.maintainers = with maintainers; [ ];
+  meta.maintainers = with maintainers; [ alexnortung ];
 }