refactor: Streamline EPUB handling with new split modes and improved error management

- Removed legacy AI Tool references and unnecessary fields from the README and various components.
- Introduced new EPUB split modes (toc, regex, tag) to enhance flexibility in chapter extraction.
- Updated import and chapter management components to utilize the new EPUB split functionality.
- Improved error handling in the login API route for better user feedback.
- Cleaned up unused files and optimized the overall code structure for maintainability.

lib/auth-context.tsx

@@ -68,6 +68,9 @@ async function initializeGoogleIdentity(clientId: string): Promise<void> {
 
   if (googleInitializedClientId === clientId) return
 
+  const hostname = typeof window !== "undefined" ? window.location.hostname : ""
+  const isLocalHost = hostname === "localhost" || hostname === "127.0.0.1"
+
   // Re-initialize with new clientId (or first time)
   googleApi.initialize({
     client_id: clientId,
@@ -86,7 +89,8 @@ async function initializeGoogleIdentity(clientId: string): Promise<void> {
     },
     auto_select: false,
     cancel_on_tap_outside: true,
-    use_fedcm_for_prompt: true,
+    // FedCM on localhost often yields tokens backend cannot verify; production keeps FedCM.
+    use_fedcm_for_prompt: !isLocalHost,
   })
 
   googleInitializedClientId = clientId

lib/epub-split.ts

@@ -0,0 +1,31 @@
+export type EpubSplitMode = "toc" | "regex" | "tag"
+
+export const EPUB_HTML_TAG_PRESETS = [
+  { id: "a", name: "Thẻ <a> (anchor / mục lục liên kết)", tag: "a" },
+  { id: "h2", name: "Thẻ <h2>", tag: "h2" },
+  { id: "h1", name: "Thẻ <h1>", tag: "h1" },
+  { id: "h3", name: "Thẻ <h3>", tag: "h3" },
+  { id: "p", name: "Thẻ <p>", tag: "p" },
+] as const
+
+export const DEFAULT_EPUB_CHAPTER_TAG = "a"
+
+export function splitModeLabel(mode: string | undefined): string {
+  if (mode === "regex") return "Regex"
+  if (mode === "tag") return "Thẻ HTML"
+  return "TOC"
+}
+
+export function appendEpubSplitFormFields(
+  form: FormData,
+  splitMode: EpubSplitMode,
+  options?: { chapterRegex?: string; chapterTag?: string },
+) {
+  form.append("splitMode", splitMode)
+  if (splitMode === "regex" && options?.chapterRegex) {
+    form.append("chapterRegex", options.chapterRegex)
+  }
+  if (splitMode === "tag") {
+    form.append("chapterTag", (options?.chapterTag || DEFAULT_EPUB_CHAPTER_TAG).trim() || DEFAULT_EPUB_CHAPTER_TAG)
+  }
+}

lib/mod-ai-tools.ts

@@ -1,25 +0,0 @@
-export const MOD_AI_PREFILL_STORAGE_KEY = "mod:ai-tool:novel-prefill"
-export const MOD_AI_MODEL_STORAGE_KEY = "mod:ai-tool:model"
-export const MOD_AI_WEB_DEFAULT_MODEL = "gpt-4o-mini-search-preview"
-
-export const MOD_AI_WEB_MODEL_OPTIONS = [
-  {
-    value: "gpt-4o-mini-search-preview",
-    label: "gpt-4o-mini-search-preview (nhanh)",
-  },
-  {
-    value: "gpt-4o-search-preview",
-    label: "gpt-4o-search-preview (chat luong cao)",
-  },
-] as const
-
-export type AINovelPrefillPayload = {
-  title?: string
-  originalTitle?: string
-  authorName?: string
-  originalAuthorName?: string
-  description?: string
-  coverUrl?: string
-  status?: "Đang ra" | "Hoàn thành" | "Tạm ngưng"
-  genresSuggested?: string[]
-}