using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.ServiceProcess;
using System.Data.SqlClient;
using System.IO;
using System.Timers;

namespace WindowsService1
{
	public class InventoryService : System.ServiceProcess.ServiceBase
	{
		/// <summary> 
		/// Required designer variable.
		/// </summary>
		private System.ComponentModel.Container components = null;
		private Timer tmrTimer;

		public InventoryService()
		{
			// This call is required by the Windows.Forms Component Designer.
			InitializeComponent();

			// TODO: Add any initialization after the InitComponent call
		}

		// The main entry point for the process
		static void Main()
		{
			System.ServiceProcess.ServiceBase[] ServicesToRun;
	
			// More than one user Service may run within the same process. To add
			// another service to this process, change the following line to
			// create a second service object. For example,
			//
			//   ServicesToRun = new System.ServiceProcess.ServiceBase[] {new Service1(), new MySecondUserService()};
			//
			ServicesToRun = new System.ServiceProcess.ServiceBase[] { new InventoryService() };

			System.ServiceProcess.ServiceBase.Run(ServicesToRun);
		}

		/// <summary> 
		/// Required method for Designer support - do not modify 
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			// 
			// InventoryService
			// 
			this.ServiceName = "InventoryService";

		}

		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if (components != null) 
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		/// <summary>
		/// Set things in motion so your service can do its work.
		/// </summary>
		protected override void OnStart(string[] args)
		{
			// TODO: Add code here to start your service.

			// TODO: Add code here to start your service
			if (tmrTimer == null)
			{
				tmrTimer = new Timer();
				tmrTimer.Elapsed += new ElapsedEventHandler(OnTimer);
				//Let the timer trigger once a minute
				tmrTimer.Interval = 60000;
				tmrTimer.Enabled = true;
			} 
			else 
			{
				tmrTimer.Start();
			}
		}
 
		/// <summary>
		/// Stop this service.
		/// </summary>
		protected override void OnStop()
		{
			// TODO: Add code here to perform any tear-down necessary to stop your service.
			if(tmrTimer != null)
				tmrTimer.Stop();
		}
		public static void OnTimer(Object source,System.Timers.ElapsedEventArgs e)
		{
			InventorySystem.connect(); 	
		}
	}
	public  class InventorySystem
	{
		static SqlConnection objSqlConnection ;
		static SqlDataReader objSqlDataReader;
		static SqlCommand objSqlCommand;

		public static void connect()
		{
			try
			{
				string str = "Server=sam;Database=Inventory;User Id=sa;Password=;";
				objSqlConnection = new SqlConnection(str);
				objSqlConnection.Open();
				objSqlCommand = new SqlCommand("Select ItemNo,Description,Quantity,ReOrderLevel from Item",objSqlConnection);
				objSqlDataReader = objSqlCommand.ExecuteReader();
				while(objSqlDataReader.Read())
				{
					if(Convert.ToInt32(objSqlDataReader[2].ToString()) <= Convert.ToInt32(objSqlDataReader[5].ToString()))
					{
						FileStream objFileStream = new FileStream(@"c:\Log.Txt",FileMode.OpenOrCreate,FileAccess.Write);
						StreamWriter objStreamWriter = new StreamWriter(objFileStream);
						objStreamWriter.BaseStream.Seek(0,SeekOrigin.End);
						objStreamWriter.WriteLine(objSqlDataReader[0].ToString()+","+objSqlDataReader[1].ToString()+","+objSqlDataReader[3].ToString());
						objStreamWriter.Flush();
						objFileStream.Close();
					}
				}
				objSqlConnection.Close();
			}
			catch(Exception ex)
			{
				throw ex;
			}
		}
	}
}