using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Diagnostics;

namespace AutoShutDown
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            //MessageBox.Show(Process.GetCurrentProcess().ProcessName.ToString());
            //Only one instance can run at the same time.
            Process[] tylan = Process.GetProcessesByName("AutoShutDown");
            if (tylan.Count() > 1)
            {
                MessageBox.Show("Sorry, the instance of this program has already run on this computer. You can not run it again.");
                System.Diagnostics.Process.GetCurrentProcess().Kill();
            }
            InitializeComponent();
            AddProcesses();
        }

        private void AddProcesses()
        {
            var processes = System.Diagnostics.Process.GetProcesses();
            foreach (var process in processes) 
            {
                Processes.Items.Add(process.ProcessName.ToString());
            }
        }

        private void Processes_SelectedIndexChanged(object sender, EventArgs e)
        {
            Processes.Text = Processes.SelectedItem.ToString();
        }

        private void OKButton_Click(object sender, EventArgs e)
        {
            //Check if the process has been selected.
            if (Processes.Text == "")
            {
                MessageBox.Show("Please select a process first.");
            }
            else
            {
                //Check the process's status every 5 miniutes.
                System.Timers.Timer tmr = new System.Timers.Timer(5000);
                tmr.Elapsed += new System.Timers.ElapsedEventHandler(CheckProcess);
                tmr.AutoReset = true;
                tmr.Enabled = true;
                this.Hide();
            }
        }

        private void CheckProcess(object source, System.Timers.ElapsedEventArgs e) 
        {
            int numOfTheProcesses = 0;
            var processes = System.Diagnostics.Process.GetProcesses();
            foreach (var process in processes) 
            {
                string TheProcessName = "";
                if (Processes.InvokeRequired)
                {
                    Processes.Invoke(new MethodInvoker(delegate { TheProcessName = Processes.Text; }));
                }
                if (process.ProcessName == TheProcessName)
                {
                    //Find the objective process.
                    //MessageBox.Show(TheProcessName);
                    numOfTheProcesses++;
                }
            }
            if (numOfTheProcesses == 0) 
            {
                //No such process, shut down the computer.
                MessageBox.Show("The computer is ready to be shut down.");
                //Shut down the comp
                System.Diagnostics.Process myProcess = new System.Diagnostics.Process();
                myProcess.StartInfo.FileName = "cmd.exe";
                myProcess.StartInfo.UseShellExecute = false;
                myProcess.StartInfo.RedirectStandardInput = true;
                myProcess.StartInfo.RedirectStandardOutput = true;
                myProcess.StartInfo.RedirectStandardError = true;
                myProcess.StartInfo.CreateNoWindow = true;
                myProcess.Start();
                myProcess.StandardInput.WriteLine("shutdown -s -t 0"); 
            }
        }
    }
}