using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading;

namespace lab3_sgbd
{
    class Program
    {
        static SqlConnection connection;

        static public void ShowSample()
        {
            connection = new SqlConnection(ConfigurationManager.ConnectionStrings["db"].ConnectionString);
            connection.Open();

            SqlCommand selectCommand1 = new SqlCommand("select * from Managers where Mid = 1", connection);
            SqlCommand selectCommand2 = new SqlCommand("select * from Employees where Eid = 4", connection);
            SqlDataReader selection1 = selectCommand1.ExecuteReader();
            selection1.Read();
            Console.WriteLine(selection1.GetValue(1));
            selection1.Close();

            SqlDataReader selection2 = selectCommand2.ExecuteReader();
            selection2.Read();
            Console.WriteLine(selection2.GetValue(1));
            selection2.Close();
        }

        static public void RunThread1()
        {
            connection = new SqlConnection(ConfigurationManager.ConnectionStrings["db"].ConnectionString);
            connection.Open();

            for (int i = 0; i < 3; i++)
            {
                try
                {
                    SqlCommand command = new SqlCommand("tran1", connection);

                    command.CommandType = CommandType.StoredProcedure;
                    command.ExecuteNonQuery();
                    ShowSample();
                    Console.WriteLine("Thread1 executed transaction successfully after " + i + " tries!!\n");
                    return;
                }
                catch (SqlException e)
                {
                    Console.WriteLine("Thread1 is ded but still trying -----> deadlock!!\n ");
                }

            }
            Console.WriteLine("Thread1 is ded forever :(!!\n");


        }

        static public void RunThread2()
        {
            SqlConnection connection = new SqlConnection(ConfigurationManager.ConnectionStrings["db"].ConnectionString);
            connection.Open();
            for (int i = 0; i < 3; i++)
            {
                try
                {
                    SqlCommand command = new SqlCommand("tran2", connection);

                    command.CommandType = CommandType.StoredProcedure;
                    command.ExecuteNonQuery();
                    ShowSample();
                    Console.WriteLine("Thread2 executed transaction successfully after " + i + " tries!!\n");

                    return;
                }
                catch (SqlException e)
                {
                    Console.WriteLine("Thread2 is ded  but still trying -----> deadlock!!\n ");
                }

            }
            Console.WriteLine("Thread2 is ded forever :(!!\n");

        }


        static public void Main(string[] args)
        {

            Thread thr1 = new Thread(new ThreadStart(RunThread1));
            Thread thr2 = new Thread(new ThreadStart(RunThread2));

            thr1.Start();
            thr2.Start();

            Console.ReadLine();

        }
    }
}