added shop function

src/c/shop.c

@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+
+#include "shop.h"
+
+int openShop(Item *availableItems)
+{
+    int userInput;
+    fflush(stdout);
+    bool shopIsOpen = 1;
+    while (shopIsOpen == 1)
+    {
+        printf("*** SHOP-Items *** \n\n");
+
+        // printf("%-5s %-30s %5s\n", "Index", "Name", "Price");
+        for (int i = 0; i < 6; i++)
+        {
+            printf("%-5d %-40s %5d$\n", availableItems[i].id, availableItems[i].itemName, availableItems[i].price);
+        }
+
+        printf("\n-> to buy items type '[index of item]' \n-> write '0' to quit the shop'\n\n");
+
+        while (scanf("%d", &userInput) != 1)
+        {
+            printf("Invalid [index]. Please try again: ");
+            fflush(stdout);
+        }
+
+        if (userInput > 0)
+        {
+            return userInput;
+            // BUY ITEM added later -> addItemToInventory(userInput);
+        }
+        else if (userInput == 0)
+        {
+            shopIsOpen = 0;
+            printf("Enjoy your items, have a great day!\n");
+            return 0;
+        }
+        else
+        {
+            printf("Invalid [index]. Please try again: ");
+        }
+    }
+
+    return 0;
+}

src/c/shop.h

@@ -0,0 +1,8 @@
+#ifndef SHOP_H
+#define SHOP_H
+
+#include "items.h"
+
+int openShop(Item *availableItems);
+
+#endif