WIP: feat(flake): Add home-manager module

flake.nix

@@ -8,6 +8,7 @@
   };
 
   outputs = {
+    self,
     nixpkgs,
     rust-overlay,
     ...
@@ -40,5 +41,10 @@
       timewall = pkgs.callPackage ./package.nix {};
       default = timewall;
     });
+
+    homeManagerModules = rec {
+      timewall = import ./hm-module.nix self;
+      default = timewall;
+    };
   };
 }

hm-module.nix

@@ -0,0 +1,107 @@
+self: {
+  config,
+  lib,
+  pkgs,
+  ...
+}: let
+  inherit (pkgs.stdenv.hostPlatform) system;
+  cfg = config.services.timewall;
+  package = self.packages.${system}.default;
+  configFormat = pkgs.formats.toml {};
+in {
+  options = {
+    services.timewall = {
+      enable = lib.mkEnableOption "timewall";
+    };
+
+    package = lib.mkPackageOption self.packages.${system} "timewall" {
+      default = "default";
+      pkgsText = "timewall.packages.\${pkgs.system}";
+    };
+
+    systemdTarget = lib.mkOption {
+      type = lib.types.str;
+      default = "graphical-session.target";
+      description = "Systemd target to bind to.";
+    };
+
+    wallpaperPath = lib.mkOption {
+      type = with lib.types; nullOr path;
+      default = null;
+      description = "Path to the HEIF/HEIC dyncamic wallpaper file to set.";
+    };
+
+    config = {
+      location = {
+        lat = lib.mkOption {
+          type = with lib.types; nullOr (either float int);
+          default = null;
+          description = "Your geographical latitude.";
+        };
+        lon = lib.mkOption {
+          type = with lib.types; nullOr (either float int);
+          default = null;
+          description = "You geographical longitude.";
+        };
+      };
+
+      setter = {
+        command = lib.mkOption {
+          type = with lib.types; nullOr listOf str;
+          default = null;
+          description = ''
+            Command to set the wallpaper. Use "%f" as a placeholder for the file path.
+            The command is NOT passed to a shell.
+          '';
+          example = ["sww" "img" "%f"];
+        };
+      };
+
+      daemon = {
+        update_interval_seconds = lib.mkOption {
+          type = with lib.types; nullOr int;
+          default = null;
+          description = "Interval between wallpaper updates in seconds.";
+        };
+      };
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    assertions = [
+      {
+        assertion = (cfg.config.location.lat != null) == (cfg.config.location.lon != null);
+        message = "Both `latitude and `longitude` must be set for timewall";
+      }
+    ];
+
+    home.packages = [cfg.package];
+
+    xdg.configFile."timewall/config.toml".source = configFormat.generate "config.toml" (
+      lib.optionalAttrs (cfg.config.location.lat != null && cfg.config.location.lon != null) {
+        inherit (cfg.config) location;
+      }
+      // lib.optionalAttrs (cfg.config.setter.command != null) {
+        inherit (cfg.config) setter;
+      }
+      // lib.optionalAttrs (cfg.config.daemon.update_interval_seconds != null) {
+        inherit (cfg.config) daemon;
+      }
+    );
+
+    systemd.user.services.timewall = {
+      Unit = {
+        Description = "Dynamic wallpapers daemon";
+        PartOf = ["graphical-session.target"];
+        X-Restart-Triggers =
+          lib.mkIf (cfg.config != {})
+          ["${config.xdg.configFile."timewall/config.toml".source}"];
+      };
+      Service.ExecStart = builtins.concatStringsSep " " [
+        "${lib.getExe package} set --daemon"
+        (lib.optionalString cfg.wallpaperPath)
+      ];
+      Install.WantedBy = [cfg.systemdTarget];
+    };
+  };
+}