Refactor checkout process to handle inventory and errors

app.py

@@ -1,5 +1,5 @@
 import os
-from flask import Flask, request, json, abort
+from flask import Flask, request, json, abort, jsonify
 from flask_cors import CORS
 
 import sentry_sdk
@@ -30,20 +30,33 @@
     obj['keyDoesntExist']
 
 Inventory = {
-    'wrench': 1,
-    'nails': 1,
-    'hammer': 1
+    'wrench': 10,
+    'nails': 100,
+    'hammer': 5,
+    '4': 2  # Botana Voice with ID '4' and 2 in stock
 }
 
-def process_order(cart):
+class InsufficientInventoryError(Exception):
+    def __init__(self, message, product_id=None):
+        super().__init__(message)
+        self.product_id = product_id
+
+def process_order(cart_items, cart_quantities):
     global Inventory
-    tempInventory = Inventory
-    for item in cart:
-        if Inventory[item['id']] <= 0:
-            raise Exception("Not enough inventory for " + item['id'])
-        else:
-            tempInventory[item['id']] -= 1
-            print 'Success: ' + item['id'] + ' was purchased, remaining stock is ' + str(tempInventory[item['id']])
+    tempInventory = Inventory.copy()
+    for item_in_cart in cart_items:
+        product_id = str(item_in_cart['id'])
+        if product_id not in tempInventory:
+            raise ValueError(f"Product ID '{product_id}' not found.")
+        requested_quantity = cart_quantities.get(product_id)
+        if not isinstance(requested_quantity, int) or requested_quantity <= 0:
+            raise ValueError(f"Invalid quantity for product ID '{product_id}'.")
+        available_stock = tempInventory[product_id]
+        if available_stock < requested_quantity:
+            raise InsufficientInventoryError(
+                f"Not enough inventory for product ID '{product_id}'.", product_id=product_id)
+        tempInventory[product_id] -= requested_quantity
+        print(f'Success: {product_id} was purchased, remaining stock is {tempInventory[product_id]}')
     Inventory = tempInventory 
 
 @app.before_request
@@ -65,11 +78,24 @@
 
 @app.route('/checkout', methods=['POST'])
 def checkout():
-
-    order = json.loads(request.data)
-    print "Processing order for: " + order["email"]
-    cart = order["cart"]
-
-    process_order(cart)
-
-    return 'Success'
+    try:
+        order_data = request.get_json()
+        print(f"Processing order for: {order_data['form']['email']}")
+        cart = order_data["cart"]
+        cart_items = cart["items"]
+        cart_quantities = cart["quantities"]
+
+        process_order(cart_items, cart_quantities)
+        return jsonify({"message": "Order successful"}), 200
+    except InsufficientInventoryError as e:
+        return jsonify({
+            "error": "InsufficientInventory",
+            "message": str(e),
+            "product_id": e.product_id
+        }), 409  # Use 409 Conflict
+    except ValueError as e:
+        return jsonify({"error": "BadRequest", "message": str(e)}), 400  # Use 400 Bad Request
+    except Exception as e:
+        # Fallback for unexpected errors
+        sentry_sdk.capture_exception(e)
+        return jsonify({"error": "InternalServerError", "message": "An unexpected error occurred."}), 500