Make safe filenames on Windows

apps/readest-app/src/utils/book.ts

@@ -1,5 +1,6 @@
 import { EXTS } from '@/libs/document';
 import { Book, BookConfig } from '@/types/book';
+import { makeSafeFilename } from './misc';
 
 export const getDir = (book: Book) => {
   return `${book.hash}`;
@@ -8,7 +9,7 @@ export const getLibraryFilename = () => {
   return 'library.json';
 };
 export const getFilename = (book: Book) => {
-  return `${book.hash}/${book.title}.${EXTS[book.format]}`;
+  return `${book.hash}/${makeSafeFilename(book.title)}.${EXTS[book.format]}`;
 };
 export const getCoverFilename = (book: Book) => {
   return `${book.hash}/cover.png`;

apps/readest-app/src/utils/misc.ts

@@ -3,3 +3,22 @@ import { md5 } from 'js-md5';
 export const uniqueId = () => Math.random().toString(36).substring(2, 9);
 
 export const getContentMd5 = (content: unknown) => md5(JSON.stringify(content));
+
+export const makeSafeFilename = (filename: string, replacement = '_') => {
+  // Windows restricted characters + control characters and reserved names
+  const unsafeCharacters = /[<>:"\/\\|?*\x00-\x1F]/g;
+  const reservedFilenames = /^(con|prn|aux|nul|com[1-9]|lpt[1-9])$/i;
+  const maxFilenameLength = 255;
+
+  let safeName = filename.replace(unsafeCharacters, replacement);
+
+  if (reservedFilenames.test(safeName)) {
+    safeName = `${safeName}${replacement}`;
+  }
+
+  if (safeName.length > maxFilenameLength) {
+    safeName = safeName.substring(0, maxFilenameLength);
+  }
+
+  return safeName.trim();
+};