using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

using System.Data.SqlClient;
using System.Web.Configuration;

using System.Text;  // Encoding

namespace BasicAjaxCSharp
{
    public partial class CheckForMessages : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            SqlConnection connection;
            SqlCommand command;
            SqlDataReader reader;
            string recipient = "";

            // Set the content type
            Response.ContentType = "text/plain";
            Response.ContentEncoding = Encoding.UTF8;

            // Prevent page from being cached when we are polling
            Response.Expires = -1;

            if (Request.Form["recipientname"] != null
            && Request.Form["recipientname"] != "")
            {
                recipient = Request.Form["recipientname"];

                try
                {
                    connection = new SqlConnection(WebConfigurationManager.ConnectionStrings["StudentConnectionString"].ConnectionString);
                    command = new SqlCommand("SELECT * FROM StudentMessage WHERE Recipient=@Recipient ORDER BY DateReceived DESC", connection);
                    command.Parameters.AddWithValue("@Recipient", recipient);

                    using (connection)
                    {
                        connection.Open();

                        reader = command.ExecuteReader();

                        if (reader.HasRows)
                        {
                            reader.Read();
                            Response.Write((DateTime)reader["DateReceived"] + "<br/>");     // Should use StringBuilder
                            Response.Write("||");
                            Response.Write(reader["Sender"] + "<br/>");
                            Response.Write("||");
                            Response.Write(reader["Text"] + "<br/>");
                        }
                        else
                        {
                            Response.Write("-1||No matching row found");
                        }

                        connection.Close();
                    }
                }
                catch
                {
                    Response.Write("-1||An error occurred");
                }
            }
            else
            {
                Response.Write("-1||No key provided for search");
            }
        }
    }
}