Notes

import json
import os


class Product:
def __init__(self, name, price, quantity):
self.name = name
self.price = price
self.quantity = quantity

def total_value(self):
return self.price * self.quantity


class InventoryManager:
def __init__(self, filename="inventory.txt"):
self.filename = filename
self.products = []
self.load_products()

def load_products(self):
if os.path.exists(self.filename):
with open(self.filename, 'r') as f:
try:
self.products = json.load(f)
except json.JSONDecodeError:
self.products = []

def save_products(self):
with open(self.filename, 'w') as f:
json.dump([product.__dict__ for product in self.products], f, indent=2)

def add_product(self, name, price, quantity):
new_product = Product(name, price, quantity)
self.products.append(new_product)
self.save_products()

def remove_product(self, name):
self.products = [product for product in self.products if product.name != name]
self.save_products()

def update_stock(self, name, quantity):
for product in self.products:
if product.name == name:
product.quantity = quantity
self.save_products()
return
print(f"Product {name} not found in inventory.")

def list_products(self):
print("nCurrent Inventory:")
for product in self.products:
print(f"{product.name} (Price: ${product.price}, Quantity: {product.quantity})")

def get_total_value(self):
total = sum(product.total_value() for product in self.products)
return f"Total inventory value: ${total:.2f}"

def exit(self):
print("Exiting the program. Goodbye!")
exit()


def main():
inventory_manager = InventoryManager()

while True:
print("nWhat would you like to do?")
print("1. Add a new product")
print("2. Remove a product")
print("3. Update stock quantity")
print("4. List all products")
print("5. Calculate total value")
print("6. Exit program")

try:
user_choice = int(input("nEnter your choice (1-6): "))

if user_choice == 1:
name = input("Enter product name: ")
price = float(input("Enter product price: $"))
quantity = int(input("Enter product quantity: "))
inventory_manager.add_product(name, price, quantity)

elif user_choice == 2:
name = input("Enter product name to remove: ")
inventory_manager.remove_product(name)

elif user_choice == 3:
name = input("Enter product name to update: ")
quantity = int(input(f"Enter new stock quantity for {name}: "))
inventory_manager.update_stock(name, quantity)

elif user_choice == 4:
inventory_manager.list_products()

elif user_choice == 5:
print(inventory_manager.get_total_value())

elif user_choice == 6:
inventory_manager.exit()
break

except ValueError:
print("Invalid input. Please enter a number between 1 and 6.")


if __name__ == "__main__":
main()