Feat: Extract unified attachments logic

src/attachments.js

@@ -0,0 +1,38 @@
+import { asDataURL, imgToWebp, b64 } from './utils.js';
+
+export async function toAttach(file) {
+  if (!file) return null;
+  if (file instanceof File) {
+    const name = file.name || 'file', mime = (file.type || 'application/octet-stream').toLowerCase();
+    if (/^image\//.test(mime) || /\.(png|jpe?g|webp|gif)$/i.test(name)) {
+      const data = mime === 'image/webp' || /\.webp$/i.test(name) ? await asDataURL(file) : await imgToWebp(file, 2048, 94);
+      return { type: 'image_url', image_url: { url: data } };
+    }
+    if (mime === 'application/pdf' || /\.pdf$/i.test(name)) {
+      const data = await asDataURL(file), bin = b64(data);
+      return { type: 'file', file: { filename: name.endsWith('.pdf') ? name : name + '.pdf', file_data: bin } };
+    }
+    if (/^audio\//.test(mime) || /\.(wav|mp3)$/i.test(name)) {
+      const data = await asDataURL(file), bin = b64(data), fmt = /mp3/.test(mime) || /\.mp3$/i.test(name) ? 'mp3' : 'wav';
+      return { type: 'input_audio', input_audio: { data: bin, format: fmt } };
+    }
+    const data = await asDataURL(file), bin = b64(data);
+    return { type: 'file', file: { filename: name, file_data: bin } };
+  }
+  if (file && file.name == null && file.data) {
+    const name = file.name || 'file', mime = (file.mime || 'application/octet-stream').toLowerCase();
+    if (/^image\//.test(mime)) {
+      const url = `data:${mime};base64,${file.data}`;
+      return { type: 'image_url', image_url: { url } };
+    }
+    if (mime === 'application/pdf') {
+      return { type: 'file', file: { filename: name, file_data: file.data } };
+    }
+    if (/^audio\//.test(mime)) {
+      const fmt = /mp3/.test(mime) ? 'mp3' : 'wav';
+      return { type: 'input_audio', input_audio: { data: file.data, format: fmt } };
+    }
+    return { type: 'file', file: { filename: name, file_data: file.data } };
+  }
+  return null;
+}