<?php
class database {
	public function connectToDatabase() {
		$this->hostname = "localhost";
		$this->username = "root";
		$this->password = "";
		$this->database = "twaddlr";

		mysql_connect($this->hostname, $this->username, $this->password);
		mysql_select_db($this->database);

		$this->connected = true;
	}
}

class system {
	public function __construct() {
		# Allows access to the database
		global $database;

		# Make sure we are connected to the database
		$database->connectToDatabase();
	}

	# Checks if the user is logged in, if they are it returns true, else false
	public function loggedin() {
		# Allows access to the database
		global $database;

		# If the session hasn't already been started, start one
		if (!isset($_SESSION)) {
			session_start();
		}

		# Check if the username and password sessions are set, if they are then the user is logged in
		if (isset($_SESSION['sys_username']) AND isset($_SESSION['sys_password'])) {
			return true;
		}
		else {
			# Not logged in, return false
			return false;
		}
	}

	# Returns the current user's username
	public function username() {
		# Allows access to the database
		global $database;

		# Returns the value of the 'sys_username' session
		return $_SESSION['sys_username'];
	}

	# Returns the current user's email
	public function email() {
		# Allows access to the database
		global $database;

		# Returns the value of the 'sys_email' session
		return $_SESSION['sys_email'];
	}

	# Function to prevent MySQL injection
	public function clean($string) {
		# Allows access to the database
		global $database;

		# Clean $string
		$string = stripslashes($string);
		$string = mysql_real_escape_string($string);

		# Send back the cleaned string
		return $string;
	}

	# Check if a username and password combination is valid, returns true if valid, else false
	public function validate($username, $password) {
		# Allows access to the database
		global $database;

		# MD5 the password
		$password = md5($password);

		# Clean the username and password to prevent injection
		$username = $this->clean($username);
		$password = $this->clean($password);

		# Search for records where username and password match
		$sql = "SELECT * FROM users WHERE username='$username' AND password='$password'";
		$result = mysql_query($sql);

		# Count the number of returned rows
		$count = mysql_num_rows($result);

		# If the rows returned are equal to or greater than 1, the username and password are valid
		if ($count >= 1) {
			# If session hasnt been started, start one
			if (!isset($_SESSION)) {
				session_start();
			}

			# Get the returned results
			$res = mysql_fetch_array($result);

			# Set the results from the query as sessions
			$_SESSION['sys_username'] = $res['username'];
			$_SESSION['sys_password'] = $res['password'];
			$_SESSION['sys_email'] = $res['email'];

			# Return true as login was successful
			return true;
		}
		else {
			return false;
		}
	}

	public function recover($username) {
		# Allows access to the database
		global $database;

		# Clean the userame
		$username = $this->clean($username);

		# Search if there are any users with the entered username
		$sql = "SELECT * FROM users WHERE username='$username'";
		$result = mysql_query($sql);

		# Count the number of rows
		$count = mysql_num_rows($result);

		# If the number or results is equal to or greater than 1, it is a valid username
		if ($count <= 1) {
			# Fetch the results of the query so that we can get the user's email address
			$res = mysql_fetch_array($result);

			# Get the user's email address from the results array
			$to = $res['email'];

			# The subject for the email
			$subject = "Password Recovery";

			# The length of the randomly generated password
			$length = 6;

			# Characters that can be used in the password
			$characters = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";

			# Just set the variable so that we dont get errors appending it
			$random_password = "";

			# Create the random password
			for ($p = 0; $p < $length; $p++) {
				$random_password .= $characters[mt_rand(0, strlen($characters))];
			}

			# Get the MD5 version of the password which is what we put in the database
			$random_password_md5 = md5($random_password);

			# Update the user's password in the database
			$sql1 = "UPDATE users SET password='$random_password_md5' WHERE username='$username'";
			$result1 = mysql_query($sql1);

			# Check if the update was successful
			if (!$result1) {
				# Didn't change, exit
				return false;
			}
			else {
				# The body of the email
				$body = "We recieved a request to reset the password for your account at Twaddlr from " . $_SERVER['REMOTE_ADDR'] . "\n\nUsername: " . $username . "\nPassword: " . $random_password;

				# Check if the email was sent successfully
				if (mail($to, $subject, $body)) {
					# Sent successfully, the function has succeeded
					return true;
				}
				else {
					# Send failed, the subject has not succeeded
					return false;
				}
			}
		}
	}

	public function changePassword($username, $oldPassword, $newPassword) {
		# Allows access to the database
		global $database;

		# Clean the strings
		$username = $this->clean($username);
		$oldPassword = $this->clean($oldPassword);
		$newPassword = $this->clean($newPassword);

		# Check if the username and password match
		if ($this->validate($username, $oldPassword)) {
			# Encrypt the new password
			$newPassword = md5($newPassword);

			# Update the user's password
			$sql = "UPDATE users SET password='$newPassword' WHERE username='$username'";
			$result = mysql_query($sql);

			# Check if it was successful or not
			if ($result) {
				# Changed successfully, return true
				return true;
			}
			else {
				# Change failed, return false
				return false;
			}
		}
		else {
			# Username and password were not correct, function failed
			return false;
		}
	}

	public function changeEmail($username, $password, $newEmail) {
		# Allows access to the database
		global $database;

		# Clean the submitted data
		$username = $this->clean($username);
		$password = $this->clean($password);
		$newEmail = $this->clean($newEmail);

		# Check if the username and password are valid
		if ($this->validate($username, $password)) {
			# Username and password are valid
			$sql = "UPDATE users SET email='$newEmail' WHERE username='$username'";
			$result = mysql_query($sql);

			# Check if the field was updated successfuly
			if ($result) {
				# It was updated, return true (success)
				return true;
			}
			else {
				# Could not update the field, return false (fail)
				return false;
			}
		}
		else {
			# Username and password were wrong, return false (fail)
			return false;
		}
	}

	# Check if a username is already in use
	public function usernameAvalible($username) {
		$username = $this->clean($username);

		$sql = "SELECT * FROM users WHERE username='$username'";
		$result = mysql_query($sql);

		/////////////////////////////////////////////////////////////

	}

	# Register a user
	public function register($username, $password, $email) {
		# Get the user's IP address
		$ip = $_SERVER['REMOTE_ADDR'];

		# Clean the inputs
		$username = $this->clean($username);
		$password = $this->clean($password);
		$email = $this->clean($email);
		$ip = $this->clean($ip);

		# Encrypt the password
		$password = md5($password);

		# Insert them into the database
		$sql = "INSERT INTO users (username, password, email, signup_ip) VALUES ('$username', '$password', '$email', '$ip')";
		$result = mysql_query($sql);

		# Check if the query was successful
		if ($result) {
			# Query was successful, return true (success)
			return true;
		}
		else {
			# Query was not successful, return false (fail)
			return false;
		}
	}
}

if (!isset($_GET['act'])) {
	die();
}

$database = new database;
$system = new system;

if ($_GET['act'] == "register") {
	if (isset($_GET['username']) AND isset($_GET['password']) AND isset($_GET['email'])) {
		if ($system->register($_GET['username'], $_GET['password'], $_GET['email'])) {
			echo "created new user";
		}
		else {
			echo "failed to create new user";
		}
	}
}

if ($_GET['act'] == "login") {
	if (isset($_GET['username']) AND isset($_GET['password'])) {
		if ($system->validate($_GET['username'], $_GET['password'])) {
			echo "success";
		}
		else {
			echo "failed";
		}
	}
}

if ($_GET['act'] == "recover") {
	if (isset($_GET['username'])) {
		if ($system->recover($_GET['username'])) {
			echo "sent";
		}
		else {
			echo "send failed";
		}
	}
}

if ($_GET['act'] == "changepassword") {
	if (isset($_GET['username']) AND isset($_GET['oldpassword']) AND isset($_GET['newpassword'])) {
		if ($system->changePassword($_GET['username'], $_GET['oldpassword'], $_GET['newpassword'])) {
			echo "changed password";
		}
		else {
			echo "couldnt change password - maybe the old password was wrong";
		}
	}
}

if ($_GET['act'] == "changeemail") {
	if (isset($_GET['username']) AND isset($_GET['password']) AND isset($_GET['newemail'])) {
		if ($system->changeEmail($_GET['username'], $_GET['password'], $_GET['newemail'])) {
			echo "changed email address";
		}
		else {
			echo "couldnt change email address - maybe the username doesnt exist";
		}
	}
}
?>