feat(services): add fetch functions for models

Added two new functions, `getBySlugModel` and `getAllModels`, to the `ModelService` in `model.service.ts`. `getBySlugModel` fetches a model based on its slug while `getAllModels` fetches all models from the database.

Issue: #27
Signed-off-by: Mathis <yidhra@tuta.io>

src/services/model.service.ts

@@ -91,6 +91,54 @@ async function deleteModel(modelSlug: string): Promise<boolean> {
 	}
 }
 
+
+/**
+ * Fetches a model by slug from the database.
+ *
+ * @param {string} modelSlug - The slug of the model to be fetched.
+ * @return {Promise<IDbModel | null>} - A promise that resolves to the model if found, else null.
+ */
+async function getBySlugModel(modelSlug: string): Promise<IDbModel | null> {
+	logger.info(`Fetching model with slug: ${modelSlug}`);
+	try {
+		const model = await MysqlService.Model.getBySlug(DbHandler, modelSlug);
+		if (!model) {
+			logger.warn(`Model with slug ${modelSlug} not found`);
+			return null;
+		}
+		return model;
+	} catch (error) {
+		logger.error(`Error fetching model by slug: ${error}`);
+		return null;
+	}
+}
+
+
+/**
+ * Fetches all models from the database.
+ *
+ * @return {Promise<IDbModel[] | null>} - A promise that resolves to an array of all models if found, else null.
+ */
+async function getAllModels(): Promise<IDbModel[] | null> {
+	logger.info("Fetching all models from the database");
+	try {
+		const models = await MysqlService.Model.getAll(DbHandler);
+		if (!models || models.length === 0) {
+			logger.warn("No models found on the database");
+			return null;
+		}
+		logger.info(`Found ${models.length} model(s)`)
+		return models;
+	} catch (error) {
+		logger.error(`Error fetching all models: ${error}`);
+		return null;
+	}
+}
+
+/**
+ * ModelService is responsible for managing models.
+ * @namespace
+ */
 const ModelService = {
 	create: createModel,
 	update: updateModel,