using System;

using System.Collections.Generic;

​

public class Program

{

    static List<int> ProID = new List<int>();

    static List<string> Name = new List<string>();

    static List<int> Quant = new List<int>();

    static List<double> Price = new List<double>();

    public static void Main()

    {

        Console.WriteLine("Welcome to the Inventory Management System , HamzyManage");

        Console.WriteLine("");

        Console.WriteLine(" Please choose an option: \n 1. Add a product \n 2. Update product stock \n 3. View all products \n 4. View product by ID \n 5. Generate sales report \n 6. Exit  ");

        string input = Console.ReadLine();

        if (input == "1")

        {

            Proadd();

        }

        else if (input == "2")

        {

            Prostock();

        }

        else if (input == "3")

        {

            Proview();

        }

        else if (input == "4")

        {

            ProviewID();

        }

        else if (input == "5")

        {

            ProSales();

        }

        else if (input == "6")

        {

            Exit();

        }

        else 

        {

        }   

    }

    public static void Proadd()

    {

​

        Console.WriteLine("Whats your new product Name?");

        string input = Console.ReadLine();

         Name.Add(input);

        Console.WriteLine("Whats your product quantity");

        int input2 = Convert.ToInt32(Console.ReadLine());

        Quant.Add(input2);

        Console.WriteLine("What will you list your product price at ");

        double input3 = Convert.ToDouble(Console.ReadLine());

        Price.Add(input3);

        int count = ProID.Count;

        int id = -1;

        if (count == 0)

        {

            ProID.Add(1);

        }

        else

        {

             id = ProID.Count - 1;

            int id2 = ProID[id] + 1;

            ProID.Add(id2);

        }

        int id3 = id + 1;

        Console.WriteLine("Name: " + Name[id3] + "\n" + "Quantity: " + Quant[id3] + "\n" + "Price: " + Price[id3] + "\n" + "ID: " + ProID[id3] );

        Console.WriteLine("Product successfully added!");

        Main();

    }

    public static void Prostock()

    {

        Console.WriteLine("What is the ID of the product stock do you want to update");

        int input = Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("What is the new quantity?");

        int input2 = Convert.ToInt32(Console.ReadLine());

        int index = ProID.IndexOf(input);

        if (index != -1) {

            Quant[index] = input2; 

            Console.WriteLine("Name: " + Name[index] + "\n" + "Quantity: " + Quant[index] + "\n" + "Price: " + Price[index] + "\n" + "ID: " + ProID[index] );

        }

        else 

        {

            Console.WriteLine("Error");

        }

        Main();

    }

    public static void Proview()

    {

        foreach (string a in Name)

        {

            Console.WriteLine("Product Name: " + a);

        }

        foreach (int b in Quant)

        {

            Console.WriteLine("Product Quantity: " + b);

        }

        foreach (double c in Price)

        {

            Console.WriteLine("Product Price: " + c);

        }

        foreach (int d in ProID)

        {

            Console.WriteLine("Product ID: " + d);

        }

        Main();

    }

    public static void ProviewID()

    {

         Console.WriteLine("What is the ID of the product?");

        int input = Convert.ToInt32(Console.ReadLine());

    int index = ProID.IndexOf(input);

        if (index != -1) {

            Console.WriteLine("Product Name: " + Name[index] + "\n" + "Product Quantity: " + Quant[index] + "\n" + "Product Price: " + Price[index] + "\n" + "Product ID: " + ProID[index] );

        }

        else 

        {

            Console.WriteLine("Error");

        }

        Main();

    }

    public static void ProSales()

    {

        double totalsales = 0;

        for (int i = 0 ; i < ProID.Count ; i++)

        {

        Console.WriteLine("Enter quantity sold for " + Name[i] + "(ID : " + ProID[i] + ")" );

        int quantsold = Convert.ToInt32(Console.ReadLine());

        double sale = quantsold * Price[i];

            totalsales = totalsales + sale;

        }

        Console.WriteLine("Sales report: " + totalsales);

        Main();

    }

    public static void Exit()

    {

        Console.WriteLine("Bye!");

    }

}