Add database schema, encryption utilities, and local database service

- Implement `schema.ts` for SQLite schema creation, indexing, and sync metadata initialization.
- Develop `encryption.ts` with AES-256-GCM encryption utilities for securing database data.
- Add `database.service.ts` to manage CRUD operations with encryption support, user-specific databases, and schema initialization.
- Integrate book, chapter, and character operations with encrypted content handling and sync preparation.

components/book/AddNewBookForm.tsx

@@ -27,6 +27,7 @@ import GuideTour, {GuideStep} from "@/components/GuideTour";
 import {UserProps} from "@/lib/models/User";
 import {useTranslations} from "next-intl";
 import {LangContext, LangContextProps} from "@/context/LangContext";
+import {getOfflineDataService} from "@/lib/services/offline-data.service";
 
 interface MinMax {
     min: number;
@@ -122,29 +123,43 @@ export default function AddNewBookForm({setCloseForm}: { setCloseForm: Dispatch<
         }
         setIsAddingBook(true);
         try {
-            const bookId: string = await System.authPostToServer<string>('book/add', {
-                title: title,
-                subTitle: subtitle,
-                type: selectedBookType,
-                summary: summary,
-                serie: 0,
-                publicationDate: publicationDate,
-                desiredWordCount: wordCount,
-            }, token, lang)
-            if (!bookId) {
-                errorMessage(t('addNewBookForm.error.addingBook'));
-                setIsAddingBook(false);
-                return;
-            }
-            const book: BookProps = {
-                bookId: bookId,
+            const offlineDataService = getOfflineDataService();
+            const bookData = {
                 title,
                 subTitle: subtitle,
                 type: selectedBookType,
-                summary, serie: 0,
+                summary,
+                serie: 0,
                 publicationDate,
                 desiredWordCount: wordCount
             };
+
+            const bookId: string = await offlineDataService.createBook(
+                bookData,
+                session.user?.id || '',
+                async () => {
+                    // Only called if online
+                    const id = await System.authPostToServer<string>('book/add', {
+                        title: title,
+                        subTitle: subtitle,
+                        type: selectedBookType,
+                        summary: summary,
+                        serie: 0,
+                        publicationDate: publicationDate,
+                        desiredWordCount: wordCount,
+                    }, token, lang);
+                    if (!id) {
+                        throw new Error(t('addNewBookForm.error.addingBook'));
+                    }
+                    return id;
+                }
+            );
+
+            const book: BookProps = {
+                bookId: bookId,
+                ...bookData
+            };
+
             setSession({
                 ...session,
                 user: {

components/book/BookList.tsx

@@ -13,6 +13,7 @@ import GuideTour, {GuideStep} from "@/components/GuideTour";
 import User from "@/lib/models/User";
 import {useTranslations} from "next-intl";
 import {LangContext, LangContextProps} from "@/context/LangContext";
+import {getOfflineDataService} from "@/lib/services/offline-data.service";
 
 export default function BookList() {
     const {session, setSession} = useContext(SessionContext);
@@ -113,7 +114,10 @@ export default function BookList() {
     async function getBooks(): Promise<void> {
         setIsLoadingBooks(true);
         try {
-            const bookResponse: BookListProps[] = await System.authGetQueryToServer<BookListProps[]>('books', accessToken, lang);
+            const offlineDataService = getOfflineDataService();
+            const bookResponse: BookListProps[] = await offlineDataService.getBooks(
+                () => System.authGetQueryToServer<BookListProps[]>('books', accessToken, lang)
+            );
             if (bookResponse) {
                 const booksByType: Record<string, BookProps[]> = bookResponse.reduce((groups: Record<string, BookProps[]>, book: BookListProps): Record<string, BookProps[]> => {
                     const imageDataUrl: string = book.coverImage ? 'data:image/jpeg;base64,' + book.coverImage : '';