dotNetStudyWithGPT/MySolution/InventoryManagement/Components/InventoryManager.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace InventoryManagement.Components
{
    internal class InventoryManager
    {
        public void AddProduct(Product product)
        {
            using (var context = new InventoryContext())
            {
                if (context.Products.Any(p => p.Name == product.Name))
                {
                    Console.WriteLine("Product with the same name already exists.");
                    return;
                }

                context.Products.Add(product);
                context.SaveChanges();
                Console.WriteLine($"{product.Name} added.");
            }
        }

        public void BuyProduct(string name, int quantity)
        {
            using (var context = new InventoryContext())
            {
                var product = context.Products.FirstOrDefault(p => p.Name == name);
                if (product == null)
                {
                    Console.WriteLine($"Cannot find the product named {name}");
                    return;
                }

                product.Quantity += quantity;
                context.SaveChanges();
                Console.WriteLine($"{product.Name}'s quantity: {product.Quantity}");
            }
        }

        public void BuyProduct(int id, int quantity)
        {
            using (var context = new InventoryContext())
            {
                var product = context.Products.Find(id);
                if (product == null)
                {
                    Console.WriteLine("Product not found.");
                    return;
                }

                product.Quantity += quantity;
                context.SaveChanges();
                Console.WriteLine($"{product.Name}'s quantity: {product.Quantity}");
            }
        }

        public void SellProduct(string name, int quantity)
        {
            using (var context = new InventoryContext())
            {
                var product = context.Products.FirstOrDefault(p => p.Name == name);
                if (product == null)
                {
                    Console.WriteLine($"Cannot find the product named {name}");
                    return;
                }

                if (product.Quantity >= quantity)
                {
                    product.Quantity -= quantity;
                    context.SaveChanges();
                    Console.WriteLine($"{quantity} units of {product.Name} sold.");
                }
                else
                {
                    Console.WriteLine($"Insufficient quantity in stock (Current: {product.Quantity})");
                }
            }
        }

        public void SellProduct(int id, int quantity)
        {
            using (var context = new InventoryContext())
            {
                var product = context.Products.Find(id);
                if (product == null)
                {
                    Console.WriteLine("Product not found.");
                    return;
                }

                if (product.Quantity >= quantity)
                {
                    product.Quantity -= quantity;
                    context.SaveChanges();
                    Console.WriteLine($"{quantity} units of {product.Name} sold.");
                }
                else
                {
                    Console.WriteLine($"Insufficient quantity in stock (Current: {product.Quantity})");
                }
            }
        }

        public void ShowInventory()
        {
            using (var context = new InventoryContext())
            {
                Console.WriteLine("********** Current Inventory **********");
                foreach (var product in context.Products)
                {
                    Console.WriteLine($"ID: {product.Id}, Name: {product.Name}, Quantity: {product.Quantity}");
                }
                Console.WriteLine("****************************************");
            }
        }
    }
}