1 files changed, 76 insertions, 0 deletions
diff --git a/lib/working_directory.ml b/lib/working_directory.ml
new file mode 100644
index 0000000..5946890
--- /dev/null
+++ b/lib/working_directory.ml
@@ -0,0 +1,76 @@
+(*─────────────────────────────────────────────────────────────────────────────┐
+│ SPDX-FileCopyrightText: 2025 toastal <https://toast.al/contact/>             │
+│ SPDX-License-Identifier: LGPL-2.1-or-later WITH OCaml-LGPL-linking-exception │
+└─────────────────────────────────────────────────────────────────────────────*)
+let working_directory : [`Dir] Eio.Path.t option ref = ref None
+
+let get () =
+	match !working_directory with
+	| Some dir -> dir
+	| None -> failwith "Working directory not set up"
+
+let set ~directory =
+	working_directory := Some directory
+
+let set_default ~env () =
+	let new_dir =
+		let cwd = Eio.Stdenv.cwd env in
+		Eio.Path.(cwd / "nix" / "tamal")
+	in
+	working_directory := Some new_dir
+
+let pp_native_path =
+	Fmt.using
+		Eio.Path.native
+		(Fmt.option (fun ppf -> Fmt.pf ppf " @@ %a" Fmt.string))
+
+(* Without the need for magic strings, we can use tabs in Nix! *)
+let root_editor_config_content =
+	{|root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_style = tab
+insert_final_newline = true
+trim_trailing_whitespace = true
+|}
+
+let set_up_editor_config ~dir ~content =
+	let editor_config_file = Eio.Path.(dir / ".editorconfig") in
+	Logs.app (fun m -> m "Writing new Nixtamal EditorConfig%a …" pp_native_path editor_config_file);
+	Eio.Path.with_open_out ~create: (`Or_truncate 0o644) editor_config_file @@ fun flow ->
+	Eio.Buf_write.with_flow flow @@ fun writer ->
+	Eio.Buf_write.string writer content
+
+let set_up_root () =
+	let dir = get () in
+	match Eio.Path.kind ~follow: true dir with
+	| `Not_found ->
+		Logs.app (fun m -> m "Creating Nixtamal directory%a" pp_native_path dir);
+		Eio.Path.mkdirs ~perm: 0o755 dir;
+		set_up_editor_config ~dir ~content: root_editor_config_content
+	| `Directory ->
+		Logs.warn (fun m -> m "Nixtamal directory already exists%a" pp_native_path dir)
+	| _ ->
+		failwith @@ Fmt.str "There is a Nixtamal path, but is not a directory%a" pp_native_path dir
+
+let darcs_context_dir = "darcs_context"
+
+let darcs_context_editor_config_content =
+	{|root = true
+|}
+
+let set_up_darcs_context_if_needed () : (unit, string) result =
+	let dir = Eio.Path.(get () / darcs_context_dir) in
+	match Eio.Path.kind ~follow: true dir with
+	| `Directory ->
+		Ok ()
+	| `Not_found ->
+		Logs.app (fun m -> m "Creating Nixtamal’s darcs_context directory%a" pp_native_path dir);
+		Eio.Path.mkdirs ~perm: 0o755 dir;
+		(* as these files are just copied over, unset rules *)
+		set_up_editor_config ~dir ~content: darcs_context_editor_config_content;
+		Ok ()
+	| _ ->
+		Error (Fmt.str "There is a Nixtamal path, but is not a directory%a" pp_native_path dir)