Add models for guidelines, incidents, plot points, issues, acts, and world data

- Introduced new models: `GuideLine`, `Incident`, `PlotPoint`, `Issue`, `Act`, and `World` for managing book-related entities.
- Integrated encryption/decryption for sensitive properties in all models using user-specific keys.
- Added methods for CRUD operations and synchronization workflows with error handling and multilingual support.
- Improved maintainability with JSDoc comments and streamlined queries.

electron/database/models/Cover.ts

@@ -0,0 +1,62 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import { getUserEncryptionKey } from "../keyManager.js";
+import System from "../System.js";
+import BookRepo, { BookCoverQuery } from "../repositories/book.repository.js";
+
+/**
+ * Cover model class for managing book cover images.
+ * Provides methods to retrieve, decrypt, and delete cover pictures.
+ */
+export default class Cover {
+    /**
+     * Retrieves and decrypts the cover picture for a specific book.
+     * @param userId - The unique identifier of the user
+     * @param bookId - The unique identifier of the book
+     * @param lang - The language for error messages ('fr' or 'en')
+     * @returns The decrypted cover image data, or an empty string if not found
+     */
+    public static async getCoverPicture(userId: string, bookId: string, lang: 'fr' | 'en' = 'fr'): Promise<string> {
+        const coverQuery: BookCoverQuery = BookRepo.fetchBookCover(userId, bookId, lang);
+        if (coverQuery) {
+            const userEncryptionKey: string = getUserEncryptionKey(userId);
+            return System.decryptDataWithUserKey(coverQuery.cover_image, userEncryptionKey);
+        } else {
+            return '';
+        }
+    }
+
+    /**
+     * Deletes the cover picture association for a specific book.
+     * Clears the cover image reference in the database.
+     * @param userId - The unique identifier of the user
+     * @param bookId - The unique identifier of the book
+     * @param lang - The language for error messages ('fr' or 'en')
+     * @returns True if the cover was successfully deleted, false otherwise
+     */
+    public static async deleteCoverPicture(userId: string, bookId: string, lang: 'fr' | 'en' = 'fr'): Promise<boolean> {
+        const existingCoverName: string = await Cover.getCoverPicture(userId, bookId, lang);
+        return BookRepo.updateBookCover(bookId, '', userId, lang);
+    }
+
+    /**
+     * Retrieves and decrypts a picture file, returning it as a base64-encoded string.
+     * @param userId - The unique identifier of the user
+     * @param userKey - The user's encryption key for decrypting the image path
+     * @param image - The encrypted image file path
+     * @param lang - The language for error messages ('fr' or 'en')
+     * @returns The base64-encoded image data, or an empty string if the image cannot be read
+     */
+    public static getPicture(userId: string, userKey: string, image: string, lang: 'fr' | 'en' = 'fr'): string {
+        if (!image) return '';
+        try {
+            const decryptedFileName: string = System.decryptDataWithUserKey(image, userKey);
+            const userDirectory: string = path.join('');
+            fs.accessSync(userDirectory, fs.constants.R_OK);
+            const fileData: Buffer = fs.readFileSync(userDirectory);
+            return fileData.toString('base64');
+        } catch (error: unknown) {
+            return '';
+        }
+    }
+}