Add batch price retrieval for products in region

- Implemented a new endpoint to fetch prices for multiple products in a specified region in a single request, improving efficiency.
- Added validation for input parameters to ensure proper data handling.
- Updated the FalukantService to calculate prices based on knowledge factors and worth percentages for each product.
- Modified the frontend to utilize the new batch endpoint, optimizing the loading of product prices.

backend/services/falukantService.js

@@ -5133,6 +5133,57 @@ class FalukantService extends BaseService {
         return regions;
     }
 
+    async getProductPricesInRegionBatch(hashedUserId, productIds, regionId) {
+        const user = await this.getFalukantUserByHashedId(hashedUserId);
+        const character = await FalukantCharacter.findOne({ where: { userId: user.id } });
+        if (!character) {
+            throw new Error(`No FalukantCharacter found for user with id ${user.id}`);
+        }
+
+        if (!Array.isArray(productIds) || productIds.length === 0) {
+            return {};
+        }
+
+        // Hole alle Produkte auf einmal
+        const products = await ProductType.findAll({
+            where: { id: { [Op.in]: productIds } }
+        });
+
+        // Hole alle Knowledge-Werte auf einmal
+        const knowledges = await Knowledge.findAll({
+            where: {
+                characterId: character.id,
+                productId: { [Op.in]: productIds }
+            }
+        });
+        const knowledgeMap = new Map(knowledges.map(k => [k.productId, k.knowledge]));
+
+        // Hole alle TownProductWorth-Werte auf einmal
+        const townWorths = await TownProductWorth.findAll({
+            where: {
+                productId: { [Op.in]: productIds },
+                regionId: regionId
+            }
+        });
+        const worthMap = new Map(townWorths.map(tw => [tw.productId, tw.worthPercent]));
+
+        // Berechne Preise für alle Produkte
+        const prices = {};
+        for (const product of products) {
+            const knowledgeFactor = knowledgeMap.get(product.id) || 0;
+            const worthPercent = worthMap.get(product.id) || 50;
+            
+            const basePrice = product.sellCost * (worthPercent / 100);
+            const min = basePrice * 0.6;
+            const max = basePrice;
+            const price = min + (max - min) * (knowledgeFactor / 100);
+            
+            prices[product.id] = Math.round(price * 100) / 100; // Auf 2 Dezimalstellen runden
+        }
+
+        return prices;
+    }
+
     async getProductPriceInRegion(hashedUserId, productId, regionId) {
         const user = await this.getFalukantUserByHashedId(hashedUserId);
         const character = await FalukantCharacter.findOne({ where: { userId: user.id } });