feat: add modular services and repositories for improved code organization

Introduce repository pattern across multiple services, including `favorites`, `tags`, `sessions`, `reports`, `auth`, and more. Decouple crypto functionalities into modular services like `HashingService`, `JwtService`, and `EncryptionService`. Improve testability and maintainability by simplifying dependencies and consolidating utility logic.

backend/src/favorites/favorites.service.ts

@@ -4,46 +4,32 @@ import {
 	Logger,
 	NotFoundException,
 } from "@nestjs/common";
-import { and, eq } from "drizzle-orm";
-import { DatabaseService } from "../database/database.service";
-import { contents, favorites } from "../database/schemas";
+import { FavoritesRepository } from "./repositories/favorites.repository";
 
 @Injectable()
 export class FavoritesService {
 	private readonly logger = new Logger(FavoritesService.name);
 
-	constructor(private readonly databaseService: DatabaseService) {}
+	constructor(private readonly favoritesRepository: FavoritesRepository) {}
 
 	async addFavorite(userId: string, contentId: string) {
 		this.logger.log(`Adding favorite: user ${userId}, content ${contentId}`);
-		// Vérifier si le contenu existe
-		const content = await this.databaseService.db
-			.select()
-			.from(contents)
-			.where(eq(contents.id, contentId))
-			.limit(1);
-
-		if (content.length === 0) {
+		
+		const content = await this.favoritesRepository.findContentById(contentId);
+		if (!content) {
 			throw new NotFoundException("Content not found");
 		}
 
 		try {
-			return await this.databaseService.db
-				.insert(favorites)
-				.values({ userId, contentId })
-				.returning();
+			return await this.favoritesRepository.add(userId, contentId);
 		} catch (_error) {
-			// Probablement une violation de clé primaire (déjà en favori)
 			throw new ConflictException("Content already in favorites");
 		}
 	}
 
 	async removeFavorite(userId: string, contentId: string) {
 		this.logger.log(`Removing favorite: user ${userId}, content ${contentId}`);
-		const result = await this.databaseService.db
-			.delete(favorites)
-			.where(and(eq(favorites.userId, userId), eq(favorites.contentId, contentId)))
-			.returning();
+		const result = await this.favoritesRepository.remove(userId, contentId);
 
 		if (result.length === 0) {
 			throw new NotFoundException("Favorite not found");
@@ -53,16 +39,6 @@ export class FavoritesService {
 	}
 
 	async getUserFavorites(userId: string, limit: number, offset: number) {
-		const data = await this.databaseService.db
-			.select({
-				content: contents,
-			})
-			.from(favorites)
-			.innerJoin(contents, eq(favorites.contentId, contents.id))
-			.where(eq(favorites.userId, userId))
-			.limit(limit)
-			.offset(offset);
-
-		return data.map((item) => item.content);
+		return await this.favoritesRepository.findByUserId(userId, limit, offset);
 	}
 }