fix: rework home-manager modules to allow option merging

lib/home/default.nix

@@ -1,7 +1,26 @@
 { core-inputs, user-inputs, snowfall-lib }:
 
 let
-  inherit (core-inputs.nixpkgs.lib) assertMsg foldl head tail concatMap optionalAttrs mkIf filterAttrs mapAttrs' mkMerge mapAttrsToList optionals mkDefault mkAliasDefinitions;
+  inherit (core-inputs.nixpkgs.lib)
+    assertMsg
+    foldl
+    head
+    tail
+    concatMap
+    optionalAttrs
+    optional
+    mkIf
+    filterAttrs
+    mapAttrs'
+    mkMerge
+    mapAttrsToList
+    optionals
+    mkDefault
+    traceSeqN
+    mkAliasDefinitions
+    mkAliasAndWrapDefinitions
+    mkOption
+    types;
 
   user-homes-root = snowfall-lib.fs.get-snowfall-file "homes";
   user-modules-root = snowfall-lib.fs.get-snowfall-file "modules";
@@ -136,7 +155,11 @@ in
           src = "${user-modules-root}/home";
         };
 
-        user-home-modules-list = builtins.attrValues user-home-modules;
+        user-home-modules-list = mapAttrsToList
+          (module-path: module: args@{ pkgs, ... }: (module args) // {
+            _file = "${user-homes-root}/${module-path}/default.nix";
+          })
+          user-home-modules;
 
         create-home' = home-metadata:
           let
@@ -160,6 +183,30 @@ in
     create-home-system-modules = users:
       let
         created-users = create-homes users;
+        user-home-modules = snowfall-lib.module.create-modules {
+          src = "${user-modules-root}/home";
+        };
+
+        shared-modules = mapAttrsToList
+          (module-path: module: {
+            _file = "${user-modules-root}/home/${module-path}/default.nix";
+
+            config = {
+              home-manager.sharedModules = [ module ];
+            };
+          })
+          user-home-modules;
+
+        snowfall-user-home-module = {
+          _file = "virtual:snowfallorg/modules/home/user/default.nix";
+
+          config = {
+            home-manager.sharedModules = [
+              ../../modules/home/user/default.nix
+            ];
+          };
+        };
+
         extra-special-args-module =
           args@{ config
           , pkgs
@@ -184,15 +231,17 @@ in
               };
             };
           };
+
         system-modules = builtins.map
           (name:
             let
               created-user = created-users.${name};
               user-module = head created-user.modules;
-              other-modules = tail created-user.modules;
+              other-modules = users.users.${name}.modules or [ ];
               user-name = created-user.specialArgs.user;
             in
             args@{ config
+            , options
             , pkgs
             , host ? ""
             , ...
@@ -200,52 +249,56 @@ in
             let
               host-matches = created-user.specialArgs.host == host;
 
-              # @NOTE(jakehamilton): We *must* specify named attributes here in order
+              # @NOTE(jakehamilton): To conform to the config structure of home-manager, we have to
-              # for home-manager to provide them.
+              # remap the options coming from `snowfallorg.user.<name>.home.config` since `mkAliasDefinitions`
-              wrapped-user-module = home-args@{ pkgs, lib, osConfig ? { }, ... }:
+              # does not let us target options within a submodule.
-                let
+              wrap-user-options = user-option:
-                  user-module-result = import user-module home-args;
+                if (user-option ? "_type") && user-option._type == "merge" then
-                  user-imports =
+                  user-option // {
-                    if user-module-result ? imports then
+                    contents = builtins.map
-                      user-module-result.imports
+                      (merge-entry:
-                    else
+                        merge-entry.${user-name}.home.config or { }
-                      [ ];
+                      )
-                  user-config =
+                      user-option.contents;
-                    if user-module-result ? config then
+                  }
-                      user-module-result.config
+                else
-                    else
+                  (builtins.trace ''
-                      builtins.removeAttrs user-module-result [ "imports" "options" "_file" ];
+                    =============
-                  user = created-user.specialArgs.user;
+                    Snowfall Lib:
-                in
+                    Option value for `snowfallorg.user.${user-name}` was not detected to be merged.
-                {
-                  _file = builtins.toString user-module;
-                  imports = user-imports;
 
-                  config = mkMerge [
+                    Please report the issue on GitHub with a link to your configuration so we can debug the problem:
-                    user-config
+                      https://github.com/snowfallorg/lib/issues/new
-                    ({
+                    =============
-                      snowfallorg.user.name = mkDefault user;
+                  '')
-                    })
+                    user-option;
-                    (osConfig.snowfallorg.resolved-homes.${user} or { })
-                  ];
-                };
             in
             {
               _file = "virtual:snowfallorg/home/user/${name}";
 
               config = mkIf host-matches {
                 # Initialize user information.
-                snowfallorg.user.${user-name} = { };
+                snowfallorg.user.${user-name}.home.config = {
+                  snowfallorg.user.name = mkDefault user-name;
+                };
 
                 home-manager = {
-                  users.${user-name} = wrapped-user-module;
+                  users.${user-name} = mkAliasAndWrapDefinitions wrap-user-options options.snowfallorg.user;
-                  sharedModules = other-modules;
+
+                  # sharedModules = other-modules ++ optional config.snowfallorg.user.${user-name}.home.enable wrapped-user-module;
+                  sharedModules = other-modules ++ optional config.snowfallorg.user.${user-name}.home.enable user-module;
                 };
               };
             }
           )
           (builtins.attrNames created-users);
       in
-      [ extra-special-args-module ] ++ system-modules;
+      [
+        extra-special-args-module
+        snowfall-user-home-module
+      ]
+      ++ (users.modules or [ ])
+      ++ shared-modules
+      ++ system-modules;
   };
 }

modules/darwin/user/default.nix

@@ -1,4 +1,4 @@
-{ pkgs, lib, options, config, ... }:
+{ pkgs, lib, options, config, inputs, ... }:
 
 let
   inherit (lib) types mkOption mkDefault foldl optionalAttrs;
@@ -17,14 +17,6 @@ let
         isHidden = mkDefault false;
       };
     });
-
-  create-resolved-home = resolved-homes: name:
-    let
-      user = cfg.user.${name};
-    in
-    resolved-homes // {
-      ${name} = user.home.config;
-    };
 in
 {
   options.snowfallorg = {
@@ -40,32 +32,51 @@ in
           };
 
           home = {
+            enable = mkOption {
+              type = types.bool;
+              default = true;
+            };
+
             path = mkOption {
               type = types.str;
               default = "/Users/${name}";
             };
 
             config = mkOption {
-              type = types.attrs;
+              # HM-compatible options taken from:
-              default = { };
+              # https://github.com/nix-community/home-manager/blob/0ee5ab611dc1fbb5180bd7d88d2aeb7841a4d179/nixos/common.nix#L14
+              type = types.submoduleWith {
+                specialArgs = {
+                  osConfig = config;
+                  modulesPath = "${inputs.home-manager}/modules";
+                } // config.home-manager.extraSpecialArgs;
+                modules = [
+                  ({ lib, modulesPath, ... }: {
+                    imports = import "${modulesPath}/modules.nix" {
+                      inherit pkgs lib;
+                      useNixpkgsModule = !config.home-manager.useGlobalPkgs;
+                    };
+
+                    config = {
+                      submoduleSupport.enable = true;
+                      submoduleSupport.externalPackageInstall = cfg.useUserPackages;
+
+                      home.username = config.users.users.${name}.name;
+                      home.homeDirectory = config.users.users.${name}.home;
+
+                      nix.package = config.nix.package;
+                    };
+                  })
+                ] ++ config.home-manager.sharedModules;
+              };
             };
           };
         };
       }));
     };
-
-    resolved-homes = mkOption {
-      type = types.attrs;
-      default = { };
-      internal = true;
-    };
   };
 
   config = {
-    users.users = (foldl (create-system-users) { } (user-names));
+    users.users = (foldl create-system-users { } (user-names));
-
-    snowfallorg = {
-      resolved-homes = (foldl (create-resolved-home) { } (user-names));
-    };
   };
 }

modules/home/user/default.nix

@@ -9,6 +9,8 @@ let
   # when being used in standalone home-manager. To remedy this, we have to refer to the arguments set directly.
   os-user-home = inputs.osConfig.users.users.${cfg.name}.home or null;
 
+  has-user-name = (cfg.user.name or null) != null;
+
   default-home-directory =
     if (os-user-home != null) then
       os-user-home
@@ -43,8 +45,8 @@ in
 
   config = mkIf cfg.user.enable {
     home = {
-      username = mkIf (cfg.user.name or null != null) (mkDefault cfg.user.name);
+      username = mkIf has-user-name (mkDefault cfg.user.name);
-      homeDirectory = mkIf (cfg.user.name or null != null) (mkDefault cfg.user.home.directory);
+      homeDirectory = mkIf has-user-name (mkDefault cfg.user.home.directory);
     };
   };
 }

modules/nixos/user/default.nix

@@ -1,4 +1,4 @@
-{ pkgs, lib, options, config, ... }:
+{ pkgs, lib, options, config, inputs, ... }:
 
 let
   inherit (lib) types mkOption mkDefault foldl optionalAttrs optional;
@@ -15,22 +15,15 @@ let
       ${name} = {
         isNormalUser = mkDefault true;
 
-        name = mkDefault cfg.name;
+        name = mkDefault name;
 
         home = mkDefault user.home.path;
         group = mkDefault "users";
 
-        extraGroups = (builtins.trace user.admin) optional user.admin "wheel";
+        extraGroups = optional user.admin "wheel";
       };
     });
 
-  create-resolved-home = resolved-homes: name:
-    let
-      user = cfg.user.${name};
-    in
-    resolved-homes // {
-      ${name} = user.home.config;
-    };
 in
 {
   options.snowfallorg = {
@@ -58,26 +51,40 @@ in
             };
 
             config = mkOption {
-              type = types.attrs;
+              # HM-compatible options taken from:
-              default = { };
+              # https://github.com/nix-community/home-manager/blob/0ee5ab611dc1fbb5180bd7d88d2aeb7841a4d179/nixos/common.nix#L14
+              type = types.submoduleWith {
+                specialArgs = {
+                  osConfig = config;
+                  modulesPath = "${inputs.home-manager}/modules";
+                } // config.home-manager.extraSpecialArgs;
+                modules = [
+                  ({ lib, modulesPath, ... }: {
+                    imports = import "${modulesPath}/modules.nix" {
+                      inherit pkgs lib;
+                      useNixpkgsModule = !config.home-manager.useGlobalPkgs;
+                    };
+
+                    config = {
+                      submoduleSupport.enable = true;
+                      submoduleSupport.externalPackageInstall = cfg.useUserPackages;
+
+                      home.username = config.users.users.${name}.name;
+                      home.homeDirectory = config.users.users.${name}.home;
+
+                      nix.package = config.nix.package;
+                    };
+                  })
+                ] ++ config.home-manager.sharedModules;
+              };
             };
           };
         };
       }));
     };
-
-    resolved-homes = mkOption {
-      type = types.attrs;
-      default = { };
-      internal = true;
-    };
   };
 
   config = {
     users.users = (foldl (create-system-users) { } (user-names));
-
-    snowfallorg = {
-      resolved-homes = (foldl (create-resolved-home) { } (user-names));
-    };
   };
 }