1 files changed, 65 insertions, 0 deletions
diff --git a/src/cache.gleam b/src/cache.gleam
new file mode 100644
index 0000000..bc9144b
--- /dev/null
+++ b/src/cache.gleam
@@ -0,0 +1,65 @@
+import gleam/dict.{type Dict}
+import gleam/int
+import gleam/list
+import gleam/option.{type Option}
+import gleam/result
+import image
+import simplifile
+
+pub type CachedImage {
+  CachedImage(data: BitArray, info: image.ImageInformation)
+}
+
+pub type ThemeCache =
+  Dict(String, Dict(Int, CachedImage))
+
+pub fn load_themes() {
+  list.fold(
+    case simplifile.read_directory("./themes") {
+      Ok(files) -> files
+      Error(_) -> []
+    },
+    dict.new(),
+    fn(accumulated_themes, theme) {
+      dict.insert(
+        accumulated_themes,
+        theme,
+        list.range(0, 9)
+          |> list.fold(dict.new(), fn(accumulated_digits, digit) {
+            case
+              simplifile.read_bits(
+                from: "./themes/"
+                <> theme
+                <> "/"
+                <> int.to_string(digit)
+                <> "."
+                <> case theme {
+                  "gelbooru-h" | "moebooru-h" | "lain" | "garukura" -> "png"
+                  _ -> "gif"
+                },
+              )
+            {
+              Ok(image_data) -> {
+                case image.get_image_information(image_data) {
+                  Ok(info) ->
+                    dict.insert(
+                      accumulated_digits,
+                      digit,
+                      CachedImage(data: image_data, info: info),
+                    )
+                  Error(_) -> accumulated_digits
+                }
+              }
+              Error(_) -> accumulated_digits
+            }
+          }),
+      )
+    },
+  )
+}
+
+pub fn get_image(cache, theme, digit) -> Option(CachedImage) {
+  dict.get(cache, theme)
+  |> result.then(fn(theme_images) { dict.get(theme_images, digit) })
+  |> option.from_result
+}