Remove DataService and OfflineDataService, refactor book and character operations to use streamlined handlers in LocalSystem

- Delete `data.service.ts` and `offline-data.service.ts`, consolidating functionality into `LocalSystem`.
- Refactor book, character, and conversation operations to adopt unified, multilingual, and session-enabled IPC handlers in `LocalSystem`.
- Simplify redundant legacy methods, enhancing maintainability and consistency.

electron/database/LocalSystem.ts

@@ -1,15 +1,19 @@
 import type { IpcMainInvokeEvent } from 'electron';
 import Store from 'electron-store';
 
-// Electron store instance for session management
+// ============================================================
+// SESSION MANAGEMENT - Auto-inject userId and lang
+// ============================================================
+
+/**
+ * Electron store instance for session management
+ * - userId: Set during login via 'login-success' event
+ * - userLang: Set via 'set-lang' handler
+ */
 const store = new Store({
     encryptionKey: 'eritors-scribe-secure-key'
 });
 
-// ============================================================
-// SESSION MANAGEMENT - Retrieve userId and lang from store
-// ============================================================
-
 /**
  * Get userId from electron-store
  * Set during login via 'login-success' event
@@ -27,122 +31,67 @@ function getLangFromSession(): 'fr' | 'en' {
 }
 
 // ============================================================
-// LEGACY HANDLERS - Manual userId injection, lang must be passed
-// Keep these for backward compatibility
-// Updated to support Promises
-// ============================================================
-
-export function createDbHandler<TReturn>(
-    handler: (userId: string) => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent): Promise<TReturn> {
-        const userId = getUserIdFromSession();
-
-        if (!userId) {
-            throw new Error('User not authenticated');
-        }
-
-        try {
-            return await handler(userId);
-        } catch (error: unknown) {
-            if (error instanceof Error) {
-                console.error(`[DB] ${error.message}`);
-                throw error;
-            }
-            throw new Error('An unknown error occurred.');
-        }
-    };
-}
-
-export function createDbHandler1<T1, TReturn>(
-    handler: (userId: string, arg1: T1) => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent, arg1: T1) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent, arg1: T1): Promise<TReturn> {
-        const userId = getUserIdFromSession();
-
-        if (!userId) {
-            throw new Error('User not authenticated');
-        }
-
-        try {
-            return await handler(userId, arg1);
-        } catch (error: unknown) {
-            if (error instanceof Error) {
-                console.error(`[DB] ${error.message}`);
-                throw error;
-            }
-            throw new Error('An unknown error occurred.');
-        }
-    };
-}
-
-export function createDbHandler2<T1, T2, TReturn>(
-    handler: (userId: string, arg1: T1, arg2: T2) => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent, arg1: T1, arg2: T2) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent, arg1: T1, arg2: T2): Promise<TReturn> {
-        const userId = getUserIdFromSession();
-
-        if (!userId) {
-            throw new Error('User not authenticated');
-        }
-
-        try {
-            return await handler(userId, arg1, arg2);
-        } catch (error: unknown) {
-            if (error instanceof Error) {
-                console.error(`[DB] ${error.message}`);
-                throw error;
-            }
-            throw new Error('An unknown error occurred.');
-        }
-    };
-}
-
-export function createDbHandler3<T1, T2, T3, TReturn>(
-    handler: (userId: string, arg1: T1, arg2: T2, arg3: T3) => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent, arg1: T1, arg2: T2, arg3: T3) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent, arg1: T1, arg2: T2, arg3: T3): Promise<TReturn> {
-        const userId = getUserIdFromSession();
-
-        if (!userId) {
-            throw new Error('User not authenticated');
-        }
-
-        try {
-            return await handler(userId, arg1, arg2, arg3);
-        } catch (error: unknown) {
-            if (error instanceof Error) {
-                console.error(`[DB] ${error.message}`);
-                throw error;
-            }
-            throw new Error('An unknown error occurred.');
-        }
-    };
-}
-
-// ============================================================
-// AUTO HANDLERS - Automatically inject userId AND lang
-// Use these for new handlers - no need to pass lang from frontend
+// UNIVERSAL HANDLER - Like a Fastify route
+// Automatically injects: userId, lang
+// Optional body parameter (for GET, POST, PUT, DELETE)
+// Generic return type (void, object, etc.)
 // ============================================================
 
 /**
- * Auto-handler with 0 parameters
- * Automatically injects: userId, lang
+ * Universal IPC handler - works like a Fastify route
+ * Automatically injects: userId, lang from session
+ *
+ * @template TBody - Request body type (use void for no params)
+ * @template TReturn - Response type (use void for no return)
  *
  * @example
- * ipcMain.handle('db:user:get', createAutoHandler<UserProps>(
- *     function(userId: string, lang: 'fr' | 'en') {
- *         return User.getUser(userId, lang);
- *     }
- * ));
+ * // GET with no params
+ * ipcMain.handle('db:books:getAll',
+ *     createHandler<void, BookProps[]>(
+ *         async (userId, body, lang) => {
+ *             return await Book.getBooks(userId, lang);
+ *         }
+ *     )
+ * );
+ * // Frontend: invoke('db:books:getAll')
  *
- * // Frontend call (no params needed):
- * const user = await window.electron.invoke('db:user:get');
+ * @example
+ * // GET with 1 param
+ * ipcMain.handle('db:book:get',
+ *     createHandler<string, BookProps>(
+ *         async (userId, bookId, lang) => {
+ *             return await Book.getBook(bookId, userId, lang);
+ *         }
+ *     )
+ * );
+ * // Frontend: invoke('db:book:get', bookId)
+ *
+ * @example
+ * // POST with object body
+ * ipcMain.handle('db:book:create',
+ *     createHandler<CreateBookData, string>(
+ *         async (userId, data, lang) => {
+ *             return await Book.addBook(userId, data, lang);
+ *         }
+ *     )
+ * );
+ * // Frontend: invoke('db:book:create', { title: '...', ... })
+ *
+ * @example
+ * // DELETE with void return
+ * ipcMain.handle('db:book:delete',
+ *     createHandler<string, void>(
+ *         async (userId, bookId, lang) => {
+ *             await Book.deleteBook(bookId, userId, lang);
+ *         }
+ *     )
+ * );
+ * // Frontend: invoke('db:book:delete', bookId)
  */
-export function createAutoHandler<TReturn>(
-    handler: (userId: string, lang: 'fr' | 'en') => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent): Promise<TReturn> {
+export function createHandler<TBody = void, TReturn = void>(
+    handler: (userId: string, body: TBody, lang: 'fr' | 'en') => TReturn | Promise<TReturn>
+): (event: IpcMainInvokeEvent, body?: TBody) => Promise<TReturn> {
+    return async function(event: IpcMainInvokeEvent, body?: TBody): Promise<TReturn> {
         const userId = getUserIdFromSession();
         const lang = getLangFromSession();
 
@@ -151,7 +100,7 @@ export function createAutoHandler<TReturn>(
         }
 
         try {
-            return await handler(userId, lang);
+            return await handler(userId, body as TBody, lang);
         } catch (error: unknown) {
             if (error instanceof Error) {
                 console.error(`[DB] ${error.message}`);
@@ -161,122 +110,3 @@ export function createAutoHandler<TReturn>(
         }
     };
 }
-
-/**
- * Auto-handler with 1 parameter
- * Automatically injects: userId, lang
- *
- * @example
- * ipcMain.handle('db:book:get', createAutoHandler1<string, BookProps>(
- *     function(userId: string, bookId: string, lang: 'fr' | 'en') {
- *         return Book.getBook(bookId, userId, lang);
- *     }
- * ));
- *
- * // Frontend call (only bookId needed):
- * const book = await window.electron.invoke('db:book:get', bookId);
- */
-export function createAutoHandler1<T1, TReturn>(
-    handler: (userId: string, arg1: T1, lang: 'fr' | 'en') => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent, arg1: T1) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent, arg1: T1): Promise<TReturn> {
-        const userId = getUserIdFromSession();
-        const lang = getLangFromSession();
-
-        if (!userId) {
-            throw new Error('User not authenticated');
-        }
-
-        try {
-            return await handler(userId, arg1, lang);
-        } catch (error: unknown) {
-            if (error instanceof Error) {
-                console.error(`[DB] ${error.message}`);
-                throw error;
-            }
-            throw new Error('An unknown error occurred.');
-        }
-    };
-}
-
-/**
- * Auto-handler with 2 parameters
- * Automatically injects: userId, lang
- *
- * @example
- * ipcMain.handle('db:book:create', createAutoHandler1<CreateBookData, string>(
- *     function(userId: string, data: CreateBookData, lang: 'fr' | 'en') {
- *         return Book.addBook(null, userId, data.title, ..., lang);
- *     }
- * ));
- *
- * // Frontend call (only data needed):
- * const bookId = await window.electron.invoke('db:book:create', bookData);
- */
-export function createAutoHandler2<T1, T2, TReturn>(
-    handler: (userId: string, arg1: T1, arg2: T2, lang: 'fr' | 'en') => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent, arg1: T1, arg2: T2) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent, arg1: T1, arg2: T2): Promise<TReturn> {
-        const userId = getUserIdFromSession();
-        const lang = getLangFromSession();
-
-        if (!userId) {
-            throw new Error('User not authenticated');
-        }
-
-        try {
-            return await handler(userId, arg1, arg2, lang);
-        } catch (error: unknown) {
-            if (error instanceof Error) {
-                console.error(`[DB] ${error.message}`);
-                throw error;
-            }
-            throw new Error('An unknown error occurred.');
-        }
-    };
-}
-
-/**
- * Auto-handler with 3 parameters
- * Automatically injects: userId, lang
- *
- * @example
- * ipcMain.handle('db:book:cover:update', createAutoHandler2<string, string, boolean>(
- *     function(userId: string, bookId: string, coverImageName: string, lang: 'fr' | 'en') {
- *         return Book.updateBookCover(userId, bookId, coverImageName, lang);
- *     }
- * ));
- *
- * // Frontend call (bookId and coverImageName needed):
- * const success = await window.electron.invoke('db:book:cover:update', bookId, coverImageName);
- */
-export function createAutoHandler3<T1, T2, T3, TReturn>(
-    handler: (userId: string, arg1: T1, arg2: T2, arg3: T3, lang: 'fr' | 'en') => TReturn | Promise<TReturn>
-): (event: IpcMainInvokeEvent, arg1: T1, arg2: T2, arg3: T3) => Promise<TReturn> {
-    return async function(event: IpcMainInvokeEvent, arg1: T1, arg2: T2, arg3: T3): Promise<TReturn> {
-        const userId = getUserIdFromSession();
-        const lang = getLangFromSession();
-
-        if (!userId) {
-            throw new Error('User not authenticated');
-        }
-
-        try {
-            return await handler(userId, arg1, arg2, arg3, lang);
-        } catch (error: unknown) {
-            if (error instanceof Error) {
-                console.error(`[DB] ${error.message}`);
-                throw error;
-            }
-            throw new Error('An unknown error occurred.');
-        }
-    };
-}
-
-export function createUniqueId(): string {
-    return crypto.randomUUID();
-}
-
-export function getCurrentDate(): string {
-    return new Date().toISOString();
-}

electron/database/models/Book.ts

@@ -254,7 +254,7 @@ export default class Book {
         return BookRepo.insertBook(id,userId,encryptedTitle,hashedTitle,encryptedSubTitle,hashedSubTitle,encryptedSummary,type,serie,publicationDate,desiredWordCount,lang);
     }
     
-    public static async getBook(userId:string,bookId: string, lang: 'fr' | 'en' = 'fr'): Promise<BookProps> {
+    public static async getBook(userId:string,bookId: string): Promise<BookProps> {
         const book:Book = new Book(bookId);
         await book.getBookInfos(userId);
         return {

electron/ipc/book.ipc.ts

@@ -1,34 +1,30 @@
 import { ipcMain } from 'electron';
-import {
-    createDbHandler2,
-    // Auto-handlers: automatically inject userId AND lang
-    createAutoHandler,
-    createAutoHandler1
-} from '../database/LocalSystem.js';
+import { createHandler } from '../database/LocalSystem.js';
 import Book from '../database/models/Book.js';
 import type { BookProps, GuideLine, GuideLineAI, Act, Issue, WorldProps } from '../database/models/Book.js';
 
-ipcMain.handle(
-    'db:book:getAll',
-    createAutoHandler<BookProps[]>(
-        async function(userId: string, lang: 'fr' | 'en') {
+// ============================================================
+// 1. GET /books - Get all books
+// ============================================================
+ipcMain.handle('db:book:books', createHandler<void, BookProps[]>(
+        async function(userId: string, _body: void, lang: 'fr' | 'en'):Promise<BookProps[]> {
             return await Book.getBooks(userId, lang);
         }
     )
 );
 
-ipcMain.handle(
-    'db:book:get',
-    createAutoHandler1<string, BookProps>(
-        async function(userId: string, bookId: string, lang: 'fr' | 'en') {
-            return await Book.getBook(bookId, userId, lang);
+// ============================================================
+// 2. GET /book/:id - Get single book
+// ============================================================
+ipcMain.handle('db:book:bookBasicInformation', createHandler<string, BookProps>(
+        async function(userId: string, bookId: string, lang: 'fr' | 'en'):Promise<BookProps> {
+            return await Book.getBook(bookId, userId);
         }
     )
 );
-// Frontend call: await window.electron.invoke('db:book:get', bookId);
 
 // ============================================================
-// 3. POST /book/basic-information
+// 3. POST /book/basic-information - Update book basic info
 // ============================================================
 interface UpdateBookBasicData {
     title: string;
@@ -41,7 +37,7 @@ interface UpdateBookBasicData {
 
 ipcMain.handle(
     'db:book:updateBasicInformation',
-    createAutoHandler1<UpdateBookBasicData, boolean>(
+    createHandler<UpdateBookBasicData, boolean>(
         function(userId: string, data: UpdateBookBasicData, lang: 'fr' | 'en') {
             return Book.updateBookBasicInformation(
                 userId,
@@ -56,22 +52,23 @@ ipcMain.handle(
         }
     )
 );
-// Frontend call: await window.electron.invoke('db:book:updateBasicInformation', data);
+// Frontend: invoke('db:book:updateBasicInformation', data)
 
 // ============================================================
-// 4. GET /book/guide-line
+// 4. GET /book/guide-line - Get guideline
 // ============================================================
 ipcMain.handle(
     'db:book:guideline:get',
-    createAutoHandler1<string, GuideLine | null>(
+    createHandler<string, GuideLine | null>(
         async function(userId: string, bookId: string, lang: 'fr' | 'en') {
             return await Book.getGuideLine(userId, bookId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:guideline:get', bookId)
 
 // ============================================================
-// 5. POST /book/guide-line
+// 5. POST /book/guide-line - Update guideline
 // ============================================================
 interface UpdateGuideLineData {
     bookId: string;
@@ -89,7 +86,7 @@ interface UpdateGuideLineData {
 
 ipcMain.handle(
     'db:book:guideline:update',
-    createAutoHandler1<UpdateGuideLineData, boolean>(
+    createHandler<UpdateGuideLineData, boolean>(
         async function(userId: string, data: UpdateGuideLineData, lang: 'fr' | 'en') {
             return await Book.updateGuideLine(
                 userId,
@@ -109,9 +106,10 @@ ipcMain.handle(
         }
     )
 );
+// Frontend: invoke('db:book:guideline:update', data)
 
 // ============================================================
-// 6. GET /book/story
+// 6. GET /book/story - Get story data (acts + issues)
 // ============================================================
 interface StoryData {
     acts: Act[];
@@ -120,7 +118,7 @@ interface StoryData {
 
 ipcMain.handle(
     'db:book:story:get',
-    createDbHandler2<string, 'fr' | 'en', StoryData>(
+    createHandler<string, StoryData>(
         async function(userId: string, bookId: string, lang: 'fr' | 'en') {
             const acts = await Book.getActsData(userId, bookId, lang);
             const issues = await Book.getIssuesFromBook(userId, bookId, lang);
@@ -131,9 +129,10 @@ ipcMain.handle(
         }
     )
 );
+// Frontend: invoke('db:book:story:get', bookId)
 
 // ============================================================
-// 7. POST /book/story
+// 7. POST /book/story - Update story
 // TODO: Implement updateStory in Book.ts
 // ============================================================
 // interface StoryUpdateData {
@@ -144,15 +143,16 @@ ipcMain.handle(
 //
 // ipcMain.handle(
 //     'db:book:story:update',
-//     createDbHandler2<StoryUpdateData, 'fr' | 'en', boolean>(
+//     createHandler<StoryUpdateData, boolean>(
 //         function(userId: string, data: StoryUpdateData, lang: 'fr' | 'en') {
 //             return Book.updateStory(userId, data.bookId, data.acts, data.mainChapters, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:story:update', data)
 
 // ============================================================
-// 8. POST /book/add
+// 8. POST /book/add - Create new book
 // ============================================================
 interface CreateBookData {
     title: string;
@@ -166,7 +166,7 @@ interface CreateBookData {
 
 ipcMain.handle(
     'db:book:create',
-    createDbHandler2<CreateBookData, 'fr' | 'en', string>(
+    createHandler<CreateBookData, string>(
         function(userId: string, data: CreateBookData, lang: 'fr' | 'en') {
             return Book.addBook(
                 null,
@@ -183,22 +183,29 @@ ipcMain.handle(
         }
     )
 );
+// Frontend: invoke('db:book:create', data)
 
 // ============================================================
-// 9. POST /book/cover
-// ============================================================
+// 9. POST /book/cover - Update book cover
 // TODO: Implement updateBookCover in Book.ts
+// ============================================================
+// interface UpdateCoverData {
+//     bookId: string;
+//     coverImageName: string;
+// }
+//
 // ipcMain.handle(
 //     'db:book:cover:update',
-//     createDbHandler3<string, string, 'fr' | 'en', boolean>(
-//         function(userId: string, bookId: string, coverImageName: string, lang: 'fr' | 'en') {
-//             return Book.updateBookCover(userId, bookId, coverImageName, lang);
+//     createHandler<UpdateCoverData, boolean>(
+//         function(userId: string, data: UpdateCoverData, lang: 'fr' | 'en') {
+//             return Book.updateBookCover(userId, data.bookId, data.coverImageName, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:cover:update', { bookId, coverImageName })
 
 // ============================================================
-// 10. POST /book/incident/new
+// 10. POST /book/incident/new - Add incident
 // ============================================================
 interface AddIncidentData {
     bookId: string;
@@ -207,15 +214,16 @@ interface AddIncidentData {
 
 ipcMain.handle(
     'db:book:incident:add',
-    createDbHandler2<AddIncidentData, 'fr' | 'en', string>(
+    createHandler<AddIncidentData, string>(
         function(userId: string, data: AddIncidentData, lang: 'fr' | 'en') {
             return Book.addNewIncident(userId, data.bookId, data.name, lang);
         }
     )
 );
+// Frontend: invoke('db:book:incident:add', { bookId, name })
 
 // ============================================================
-// 11. DELETE /book/incident/remove
+// 11. DELETE /book/incident/remove - Remove incident
 // ============================================================
 interface RemoveIncidentData {
     bookId: string;
@@ -224,15 +232,16 @@ interface RemoveIncidentData {
 
 ipcMain.handle(
     'db:book:incident:remove',
-    createDbHandler2<RemoveIncidentData, 'fr' | 'en', boolean>(
+    createHandler<RemoveIncidentData, boolean>(
         function(userId: string, data: RemoveIncidentData, lang: 'fr' | 'en') {
             return Book.removeIncident(userId, data.bookId, data.incidentId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:incident:remove', { bookId, incidentId })
 
 // ============================================================
-// 12. POST /book/plot/new
+// 12. POST /book/plot/new - Add plot point
 // ============================================================
 interface AddPlotPointData {
     bookId: string;
@@ -242,7 +251,7 @@ interface AddPlotPointData {
 
 ipcMain.handle(
     'db:book:plot:add',
-    createDbHandler2<AddPlotPointData, 'fr' | 'en', string>(
+    createHandler<AddPlotPointData, string>(
         function(userId: string, data: AddPlotPointData, lang: 'fr' | 'en') {
             return Book.addNewPlotPoint(
                 userId,
@@ -254,21 +263,23 @@ ipcMain.handle(
         }
     )
 );
+// Frontend: invoke('db:book:plot:add', { bookId, name, incidentId })
 
 // ============================================================
-// 13. DELETE /book/plot/remove
+// 13. DELETE /book/plot/remove - Remove plot point
 // ============================================================
 ipcMain.handle(
     'db:book:plot:remove',
-    createDbHandler2<string, 'fr' | 'en', boolean>(
+    createHandler<string, boolean>(
         function(userId: string, plotPointId: string, lang: 'fr' | 'en') {
             return Book.removePlotPoint(userId, plotPointId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:plot:remove', plotPointId)
 
 // ============================================================
-// 14. POST /book/issue/add
+// 14. POST /book/issue/add - Add issue
 // ============================================================
 interface AddIssueData {
     bookId: string;
@@ -277,39 +288,42 @@ interface AddIssueData {
 
 ipcMain.handle(
     'db:book:issue:add',
-    createDbHandler2<AddIssueData, 'fr' | 'en', string>(
+    createHandler<AddIssueData, string>(
         function(userId: string, data: AddIssueData, lang: 'fr' | 'en') {
             return Book.addNewIssue(userId, data.bookId, data.name, lang);
         }
     )
 );
+// Frontend: invoke('db:book:issue:add', { bookId, name })
 
 // ============================================================
-// 15. DELETE /book/issue/remove
+// 15. DELETE /book/issue/remove - Remove issue
 // ============================================================
 ipcMain.handle(
     'db:book:issue:remove',
-    createDbHandler2<string, 'fr' | 'en', boolean>(
+    createHandler<string, boolean>(
         function(userId: string, issueId: string, lang: 'fr' | 'en') {
             return Book.removeIssue(userId, issueId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:issue:remove', issueId)
 
 // ============================================================
-// 16. GET /book/worlds
+// 16. GET /book/worlds - Get worlds for book
 // ============================================================
 ipcMain.handle(
     'db:book:worlds:get',
-    createDbHandler2<string, 'fr' | 'en', WorldProps[]>(
+    createHandler<string, WorldProps[]>(
         function(userId: string, bookId: string, lang: 'fr' | 'en') {
             return Book.getWorlds(userId, bookId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:worlds:get', bookId)
 
 // ============================================================
-// 17. POST /book/world/add
+// 17. POST /book/world/add - Add world
 // ============================================================
 interface AddWorldData {
     bookId: string;
@@ -318,15 +332,16 @@ interface AddWorldData {
 
 ipcMain.handle(
     'db:book:world:add',
-    createDbHandler2<AddWorldData, 'fr' | 'en', string>(
+    createHandler<AddWorldData, string>(
         function(userId: string, data: AddWorldData, lang: 'fr' | 'en') {
             return Book.addNewWorld(userId, data.bookId, data.worldName, lang);
         }
     )
 );
+// Frontend: invoke('db:book:world:add', { bookId, worldName })
 
 // ============================================================
-// 18. POST /book/world/element/add
+// 18. POST /book/world/element/add - Add element to world
 // ============================================================
 interface AddWorldElementData {
     worldId: string;
@@ -336,7 +351,7 @@ interface AddWorldElementData {
 
 ipcMain.handle(
     'db:book:world:element:add',
-    createDbHandler2<AddWorldElementData, 'fr' | 'en', string>(
+    createHandler<AddWorldElementData, string>(
         function(userId: string, data: AddWorldElementData, lang: 'fr' | 'en') {
             return Book.addNewElementToWorld(
                 userId,
@@ -348,71 +363,77 @@ ipcMain.handle(
         }
     )
 );
+// Frontend: invoke('db:book:world:element:add', { worldId, elementName, elementType })
 
 // ============================================================
-// 19. DELETE /book/world/element/delete
+// 19. DELETE /book/world/element/delete - Remove element from world
 // ============================================================
 ipcMain.handle(
     'db:book:world:element:remove',
-    createDbHandler2<string, 'fr' | 'en', boolean>(
+    createHandler<string, boolean>(
         function(userId: string, elementId: string, lang: 'fr' | 'en') {
             return Book.removeElementFromWorld(userId, elementId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:world:element:remove', elementId)
 
 // ============================================================
-// 20. PUT /book/world/update
+// 20. PUT /book/world/update - Update world
 // TODO: Implement updateWorld in Book.ts
 // ============================================================
 // ipcMain.handle(
 //     'db:book:world:update',
-//     createDbHandler2<WorldProps, 'fr' | 'en', boolean>(
+//     createHandler<WorldProps, boolean>(
 //         function(userId: string, world: WorldProps, lang: 'fr' | 'en') {
 //             return Book.updateWorld(userId, world, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:world:update', worldData)
 
 // ============================================================
-// 21. DELETE /book/cover/delete
+// 21. DELETE /book/cover/delete - Delete book cover
 // TODO: Implement deleteCoverPicture in Book.ts
 // ============================================================
 // ipcMain.handle(
 //     'db:book:cover:delete',
-//     createDbHandler2<string, 'fr' | 'en', boolean>(
+//     createHandler<string, boolean>(
 //         function(userId: string, bookId: string, lang: 'fr' | 'en') {
 //             return Book.deleteCoverPicture(userId, bookId, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:cover:delete', bookId)
 
 // ============================================================
-// 22. DELETE /book/delete
+// 22. DELETE /book/delete - Delete book
 // ============================================================
 ipcMain.handle(
     'db:book:delete',
-    createDbHandler2<string, 'fr' | 'en', boolean>(
+    createHandler<string, boolean>(
         function(userId: string, bookId: string, lang: 'fr' | 'en') {
             return Book.removeBook(userId, bookId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:delete', bookId)
 
 // ============================================================
-// 23. GET /book/ai/guideline
+// 23. GET /book/ai/guideline - Get AI guideline
 // ============================================================
 ipcMain.handle(
     'db:book:guideline:ai:get',
-    createDbHandler2<string, 'fr' | 'en', GuideLineAI>(
+    createHandler<string, GuideLineAI>(
         function(userId: string, bookId: string, lang: 'fr' | 'en') {
             return Book.getGuideLineAI(bookId, userId, lang);
         }
     )
 );
+// Frontend: invoke('db:book:guideline:ai:get', bookId)
 
 // ============================================================
-// 24. POST /book/ai/guideline (set)
+// 24. POST /book/ai/guideline (set) - Set AI guideline
 // ============================================================
 interface SetAIGuideLineData {
     bookId: string;
@@ -427,7 +448,7 @@ interface SetAIGuideLineData {
 
 ipcMain.handle(
     'db:book:guideline:ai:set',
-    createDbHandler2<SetAIGuideLineData, 'fr' | 'en', boolean>(
+    createHandler<SetAIGuideLineData, boolean>(
         function(userId: string, data: SetAIGuideLineData, lang: 'fr' | 'en') {
             return Book.setAIGuideLine(
                 data.bookId,
@@ -444,48 +465,52 @@ ipcMain.handle(
         }
     )
 );
+// Frontend: invoke('db:book:guideline:ai:set', data)
 
 // ============================================================
-// 25. GET /book/transform/epub
-// ============================================================
+// 25. GET /book/transform/epub - Export to EPUB
 // TODO: Implement transformToEpub in Book.ts
+// ============================================================
 // ipcMain.handle(
 //     'db:book:export:epub',
-//     createDbHandler2<string, 'fr' | 'en', ExportData>(
+//     createHandler<string, ExportData>(
 //         function(userId: string, bookId: string, lang: 'fr' | 'en') {
 //             return Book.transformToEpub(userId, bookId, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:export:epub', bookId)
 
 // ============================================================
-// 26. GET /book/transform/pdf
-// ============================================================
+// 26. GET /book/transform/pdf - Export to PDF
 // TODO: Implement transformToPDF in Book.ts
+// ============================================================
 // ipcMain.handle(
 //     'db:book:export:pdf',
-//     createDbHandler2<string, 'fr' | 'en', ExportData>(
+//     createHandler<string, ExportData>(
 //         function(userId: string, bookId: string, lang: 'fr' | 'en') {
 //             return Book.transformToPDF(userId, bookId, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:export:pdf', bookId)
 
 // ============================================================
-// 27. GET /book/transform/docx
-// ============================================================
+// 27. GET /book/transform/docx - Export to DOCX
 // TODO: Implement transformToDOCX in Book.ts
+// ============================================================
 // ipcMain.handle(
 //     'db:book:export:docx',
-//     createDbHandler2<string, 'fr' | 'en', ExportData>(
+//     createHandler<string, ExportData>(
 //         function(userId: string, bookId: string, lang: 'fr' | 'en') {
 //             return Book.transformToDOCX(userId, bookId, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:export:docx', bookId)
 
 // ============================================================
-// 28. GET /book/tags
+// 28. GET /book/tags - Get tags from book
 // TODO: Implement getTagsFromBook in Book.ts
 // ============================================================
 // interface BookTags {
@@ -497,11 +522,12 @@ ipcMain.handle(
 //
 // ipcMain.handle(
 //     'db:book:tags:get',
-//     createDbHandler2<string, 'fr' | 'en', BookTags>(
+//     createHandler<string, BookTags>(
 //         function(userId: string, bookId: string, lang: 'fr' | 'en') {
 //             return Book.getTagsFromBook(userId, bookId, lang);
 //         }
 //     )
 // );
+// // Frontend: invoke('db:book:tags:get', bookId)
 
 console.log('[IPC] Book handlers registered');

electron/main.ts

@@ -6,6 +6,9 @@ import Store from 'electron-store';
 import * as fs from 'fs';
 import { getDatabaseService } from './database/database.service.js';
 
+// Import IPC handlers
+import './ipc/book.ipc.js';
+
 // Fix pour __dirname en ES modules
 const __filename = fileURLToPath(import.meta.url);
 const __dirname = path.dirname(__filename);

electron/preload.ts

@@ -1,36 +1,34 @@
 const { contextBridge, ipcRenderer } = require('electron');
 
-// Exposer des APIs sécurisées au renderer process
+/**
+ * Exposer des APIs sécurisées au renderer process
+ * Utilise invoke() générique pour tous les appels IPC
+ */
 contextBridge.exposeInMainWorld('electron', {
+  // Platform info
   platform: process.platform,
 
-  // Token management
+  // Generic invoke method - use this for all IPC calls
+  invoke: (channel: string, ...args: any[]) => ipcRenderer.invoke(channel, ...args),
+
+  // Token management (shortcuts for convenience)
   getToken: () => ipcRenderer.invoke('get-token'),
   setToken: (token: string) => ipcRenderer.invoke('set-token', token),
   removeToken: () => ipcRenderer.invoke('remove-token'),
 
-  // Language management
+  // Language management (shortcuts for convenience)
   getLang: () => ipcRenderer.invoke('get-lang'),
   setLang: (lang: 'fr' | 'en') => ipcRenderer.invoke('set-lang', lang),
 
-  // Auth events
+  // Auth events (use send for one-way communication)
   loginSuccess: (token: string, userId: string) => ipcRenderer.send('login-success', token, userId),
   logout: () => ipcRenderer.send('logout'),
 
-  // Database operations
+  // Encryption key management (shortcuts for convenience)
   generateEncryptionKey: (userId: string) => ipcRenderer.invoke('generate-encryption-key', userId),
   getUserEncryptionKey: (userId: string) => ipcRenderer.invoke('get-user-encryption-key', userId),
   setUserEncryptionKey: (userId: string, encryptionKey: string) => ipcRenderer.invoke('set-user-encryption-key', userId, encryptionKey),
+
+  // Database initialization (shortcut for convenience)
   dbInitialize: (userId: string, encryptionKey: string) => ipcRenderer.invoke('db-initialize', userId, encryptionKey),
-  dbGetBooks: () => ipcRenderer.invoke('db-get-books'),
-  dbGetBook: (bookId: string) => ipcRenderer.invoke('db-get-book', bookId),
-  dbSaveBook: (book: any, authorId?: string) => ipcRenderer.invoke('db-save-book', book, authorId),
-  dbDeleteBook: (bookId: string) => ipcRenderer.invoke('db-delete-book', bookId),
-  dbSaveChapter: (chapter: any, bookId: string, contentId?: string) => ipcRenderer.invoke('db-save-chapter', chapter, bookId, contentId),
-  dbGetCharacters: (bookId: string) => ipcRenderer.invoke('db-get-characters', bookId),
-  dbSaveCharacter: (character: any, bookId: string) => ipcRenderer.invoke('db-save-character', character, bookId),
-  dbGetConversations: (bookId: string) => ipcRenderer.invoke('db-get-conversations', bookId),
-  dbSaveConversation: (conversation: any, bookId: string) => ipcRenderer.invoke('db-save-conversation', conversation, bookId),
-  dbGetSyncStatus: () => ipcRenderer.invoke('db-get-sync-status'),
-  dbGetPendingChanges: (limit?: number) => ipcRenderer.invoke('db-get-pending-changes', limit),
 });