Traversal

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -3,3 +3,4 @@
 /build
 erl_crash.dump
 /pages
+.direnv

src/blog/traverse_tree.gleam

@@ -0,0 +1,51 @@
+import gleam/dict
+import gleam/list
+import gleam/option
+import lustre/ssg
+import simplifile
+
+pub fn add_tree(
+  config: ssg.Config(a, b, c),
+  path: String,
+  base_url_path: String,
+  file_action: fn(ssg.Config(a, b, c), String, String) ->
+    #(ssg.Config(a, b, c), option.Option(d)),
+  dir_action: fn(ssg.Config(a, b, c), dict.Dict(String, d), String, String) ->
+    #(ssg.Config(a, b, c), option.Option(d)),
+) -> #(ssg.Config(a, b, c), option.Option(d)) {
+  case simplifile.is_file(path), simplifile.is_directory(path) {
+    // file
+    Ok(True), _ -> file_action(config, path, base_url_path)
+    // directory
+    _, Ok(True) -> {
+      case simplifile.read_directory(path) {
+        Ok(files) -> {
+          let sub_tree =
+            files
+            |> list.fold(#(config, dict.new()), fn(acc, p) {
+              let config_data =
+                add_tree(
+                  acc.0,
+                  path <> "/" <> p,
+                  base_url_path <> "/" <> p,
+                  file_action,
+                  dir_action,
+                )
+
+              let new_dict = case config_data.1 {
+                option.Some(data) -> dict.insert(acc.1, p, data)
+                option.None -> acc.1
+              }
+
+              #(config_data.0, new_dict)
+            })
+
+          dir_action(sub_tree.0, sub_tree.1, path, base_url_path)
+        }
+        Error(_) -> #(config, option.None)
+      }
+    }
+    // what?
+    _, _ -> #(config, option.None)
+  }
+}