feat: refactor and separate LSP/language configurations

lib/default.nix

@@ -2,4 +2,5 @@
   dag = import ./dag.nix {inherit lib;};
   booleans = import ./booleans.nix {inherit lib;};
   types = import ./types {inherit lib;};
+  languages = import ./languages.nix {inherit lib;};
 }

lib/languages.nix

@@ -0,0 +1,25 @@
+# From home-manager: https://github.com/nix-community/home-manager/blob/master/modules/lib/booleans.nix
+{lib}: {
+  # Converts a boolean to a yes/no string. This is used in lots of
+  # configuration formats.
+  diagnosticsToLua = {
+    lang,
+    config,
+    diagnostics,
+  }:
+    lib.listToAttrs
+    (map (v: let
+        type =
+          if builtins.isString v
+          then v
+          else builtins.getAttr v.type;
+        package =
+          if builtins.isString v
+          then diagnostics.${type}.package
+          else v.package;
+      in {
+        name = "${lang}-diagnostics-${type}";
+        value = diagnostics.${type}.nullConfig package;
+      })
+      config);
+}

lib/types/default.nix

@@ -1,7 +1,9 @@
 {lib}: let
   typesDag = import ./dag.nix {inherit lib;};
   typesPlugin = import ./plugins.nix {inherit lib;};
+  typesLanguage = import ./languages.nix {inherit lib;};
 in {
   inherit (typesDag) dagOf;
   inherit (typesPlugin) pluginsOpt;
+  inherit (typesLanguage) diagnostics;
 }

lib/types/languages.nix

@@ -0,0 +1,26 @@
+{lib}:
+with lib; let
+  diagnosticSubmodule = {...}: {
+    options = {
+      type = mkOption {
+        description = "Type of diagnostic to enable";
+        type = attrNames diagnostics;
+      };
+      package = mkOption {
+        description = "Diagnostics package";
+        type = types.package;
+      };
+    };
+  };
+in {
+  diagnostics = {
+    langDesc,
+    diagnostics,
+    defaultDiagnostics,
+  }:
+    mkOption {
+      description = "List of ${langDesc} diagnostics to enable";
+      type = with types; listOf (either (enum (attrNames diagnostics)) (submodule diagnosticSubmodule));
+      default = defaultDiagnostics;
+    };
+}