파일 페이지에서의 네트워크 호출 최적화

src/lib/components/atoms/buttons/FileThumbnailButton.svelte

@@ -1,42 +1,34 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
-  import type { FileInfo } from "$lib/modules/filesystem";
+  import { browser } from "$app/environment";
+  import type { SummarizedFileInfo } from "$lib/modules/filesystem2.svelte";
   import { requestFileThumbnailDownload } from "$lib/services/file";
 
   interface Props {
-    info: Writable<FileInfo | null>;
-    onclick?: (file: FileInfo) => void;
+    info: SummarizedFileInfo;
+    onclick?: (file: SummarizedFileInfo) => void;
   }
 
   let { info, onclick }: Props = $props();
 
-  let thumbnail: string | undefined = $state();
-
-  $effect(() => {
-    if ($info) {
-      requestFileThumbnailDownload($info.id, $info.dataKey)
-        .then((thumbnailUrl) => {
-          thumbnail = thumbnailUrl ?? undefined;
-        })
-        .catch(() => {
-          // TODO: Error Handling
-          thumbnail = undefined;
-        });
-    } else {
-      thumbnail = undefined;
-    }
-  });
+  let showThumbnail = $derived(
+    browser && (info.contentType.startsWith("image/") || info.contentType.startsWith("video/")),
+  );
+  let thumbnailPromise = $derived(
+    showThumbnail ? requestFileThumbnailDownload(info.id, info.dataKey?.key) : null,
+  );
 </script>
 
-{#if $info}
-  <button
-    onclick={() => onclick?.($info)}
-    class="aspect-square overflow-hidden rounded transition active:scale-95 active:brightness-90"
-  >
+<button
+  onclick={onclick && (() => setTimeout(() => onclick(info), 100))}
+  class="aspect-square overflow-hidden rounded transition active:scale-95 active:brightness-90"
+>
+  {#await thumbnailPromise}
+    <div class="h-full w-full bg-gray-100"></div>
+  {:then thumbnail}
     {#if thumbnail}
-      <img src={thumbnail} alt={$info.name} class="h-full w-full object-cover" />
+      <img src={thumbnail} alt={info.name} class="h-full w-full object-cover" />
     {:else}
       <div class="h-full w-full bg-gray-100"></div>
     {/if}
-  </button>
-{/if}
+  {/await}
+</button>