using System;
using System.Data;
using System.Data.SqlClient;
using System.Security.Cryptography;
using System.Text;

namespace Launcher_Server.Database
{
    class Query
    {
        private SqlConnection Connection;

        public Query()
        {
            try
            {
                Connection = new SqlConnection(String.Format(Properties.Settings.Default.DatabaseString, Properties.Settings.Default.SQLName));

                OpenConnection();
            }
            catch { }
        }

        public string CalculateMD5Hash(string input)
        {
            // step 1, calculate MD5 hash from input
            MD5 md5 = System.Security.Cryptography.MD5.Create();
            byte[] inputBytes = System.Text.Encoding.ASCII.GetBytes(input);
            byte[] hash = md5.ComputeHash(inputBytes);

            // step 2, convert byte array to hex string
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < hash.Length; i++)
            {
                sb.Append(hash[i].ToString("X2"));
            }
            return sb.ToString().ToLower();
        }

        public String Login(String Username, String Password)
        {
            Password = CalculateMD5Hash(Password);
            try
            {
                OpenConnection();

                SqlCommand Command = new SqlCommand();
                Command.Connection = Connection;
                Command.CommandText = String.Format("SELECT * FROM {0}..tAccounts WHERE sUsername = '{1}' AND sUserPass = '{2}'", Properties.Settings.Default.SQLAccount, Username, Password);

                SqlDataReader Reader = Command.ExecuteReader();
                Reader.Read();

                if (Reader.HasRows)
                {
                    Reader.Close();

                    Command.CommandText = String.Format("SELECT nEMID, nAuthID FROM {0}..tAccounts WHERE sUsername = '{1}'", Properties.Settings.Default.SQLAccount, Username);

                    Reader = Command.ExecuteReader();
                    Reader.Read();

                    Int32 nEMID = Convert.ToInt32(Reader["nEMID"]);
                    Int32 nAuthID = Convert.ToInt32(Reader["nAuthID"]);

                    Reader.Close();

                    Command.CommandText = String.Format("DELETE FROM {0}..tTokens WHERE nEMID = '{1}'", Properties.Settings.Default.SQLAccount, nEMID);
                    Command.ExecuteNonQuery();

                    if (nAuthID == -1) { return "Account Banned!"; }

                    Command.CommandText = String.Format("SELECT * FROM {0}..tAuth WHERE nAuthID = '{1}' AND nLoginable = '0'", Properties.Settings.Default.SQLAccount, nAuthID);

                    Reader = Command.ExecuteReader();
                    Reader.Read();

                    if (!Reader.HasRows)
                    {
                        Reader.Close();

                        String Token = CreateToken(Utility.CreateRandom(50));

                        InsertToken(nEMID, Token);

                        return String.Format("All Good!#{0}", Token);
                    }
                    else { return "Server Maintenance!"; }
                }
                else { return "No Account Found!"; }
            }
            catch { }

            return null;
        }

        private String CreateToken(String Token)
        {
            OpenConnection();

            SqlCommand Command = new SqlCommand();
            Command.Connection = Connection;
            Command.CommandText = String.Format("SELECT * FROM {0}..tTokens WHERE sToken = '{1}'", Properties.Settings.Default.SQLAccount, Token);

            SqlDataReader Reader = Command.ExecuteReader();
            Reader.Read();

            if (Reader.HasRows)
            {
                Reader.Close();

                Token = CreateToken(Utility.CreateRandom(50));
            }

            return Token;
        }

        private void InsertToken(Int32 nEMID, String Token)
        {
            OpenConnection();

            SqlCommand Command = new SqlCommand();
            Command.Connection = Connection;
            Command.CommandText = String.Format("INSERT INTO {0}..tTokens (nEMID, sToken) VALUES ('{1}', '{2}')", Properties.Settings.Default.SQLAccount, nEMID, Token);
            Command.ExecuteNonQuery();
        }

        private void OpenConnection()
        {
            if (Connection.State != ConnectionState.Open) { Connection.Open(); }
        }

        public void Dispose() { Connection.Dispose(); }
    }
}