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<?php

	/**
	 * @author Jason
	 * @copyright 2010
	 */

	session_start();

	if ( isset( $_SESSION['username'] ) && isset( $_SESSION['password'] ) )
	{

		echo 'Logged in!';

	}
	else
	{

		$username = addslashes( $_POST['username'] );
		$password = addslashes( $_POST['password'] );

		if ( isset( $_POST['submit'] ) )
		{

			if ( $username && $password )
			{

				$connect = mysql_connect( "localhost", "root", "jason" ) or die( "Cannot connect to database!" );
				mysql_select_db( "usersystem" ) or die( "Cannot connect to database!" );

				$query = mysql_query( "SELECT * FROM `users` WHERE `username` = '$username'" );

				$numrows = mysql_num_rows( $query );

				if ( $numrows )
				{

					while ( $r = mysql_fetch_assoc( $query ) )
					{

						$dbusername = $r['username'];
						$dbpassword = $r['password'];

					}

					if ( $username == $dbusername && $password == $dbpassword )
					{

						$_SESSION['username'] = $username;
						$_SESSION['password'] = $password;

					}
					else
					{
						echo "Incorrect Password";

					}

				}
				else
				{

					echo "Username doesn't exist!";

				}

			}
			else
			{

				echo "Please enter a username and password.";

			}

		}

	?>

	<html>

		<form method='post' action="">

			Username: <input type="text" name="username"/><br />
			Password: <input type="password" name="password"/><br />

			<input type="submit" value="Log in" name="submit" />

		</form>

	</html>

	<?php

	}

	?>