FILE ZERO------------------------------------------------------------------------------------------------------------------------------core.php
---------------------------------------------------------------------------------------------------------------------------------------




<?php
session_start();

$hostname = "localhost";
$dbname = "social";
$user = "root";
$pass = "";

try {
    $db = new PDO ("mysql:host={$hostname};dbname={$dbname}", $user, $pass);
}
catch (PDOException $e) {
    echo "Errore: " . $e->getMessage();
    die();



}









PRIMO FILE-----------------------------------------------------------------------------------------------------------------------------
registrazione.php
---------------------------------------------------------------------------------------------------------------------------------------

	<?php
	include('core.php');
		if (isset($_POST['register'])) {

			$username=isset($_POST['username']);

			$password=isset($_POST['password']);

			$email=isset($_POST['email']);

			if(empty($username) || empty($password) || empty($email)){
				echo 'Riempi tutti i campi! <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			elseif (strlen($username) > 16) {
				echo 'Username troppo grande! Massimo 16 caratteri. <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			elseif (strlen($password) < 6 && strlen($password) > 20) {
				echo 'Lunghezza password non valida! <br /> Minimo 6 caratteri. <br /> Massimo 20 caratteri. <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			/*----------
			per vedere se la mail è valida

			elseif (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
				echo 'Indirizzo email non valido! <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			------------------*/
			elseif (strlen($email)>30) {
				echo 'Lunghezza email inesistente! <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}

			/*----------
			per evitare gli account doppi

			elseif (mysql_num_rows(mysql_query("SELECT * FROM users WHERE username LIKE '$username' ")) > 0) {
				echo 'Username gia in uso! Scegli un altro username!<br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			elseif (mysql_num_rows(mysql_query("SELECT * FROM users WHERE email LIKE '$email' ")) > 0) {
				echo 'Indirizzo email gia in uso! Non puoi creare altri account!<br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			------------------*/
			else{ $password= md5($password);
				if (mysql_query("INSERT INTO users (username, password, email)VALUES('$username', '$password', '$email')")) {
					echo "Registrazione andata a buon fine!";
				}else{echo 'Errore nella query: '.mysql_error();}
			}
		}


		else{
	?>

			<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="POST">
				<label>Username: <input type="text" name="username" required maxlength="16"> </label><br>
				<label>Password: <input type="password" name="password" required maxlength="20" pattern="(\s*(\S)\s*){6,20}"> </label><br>
				<label>Email: <input type="email" name="email" required maxlength="30"> </label><br>
				<input type="submit" name="register" value="Registrati">
			</form>
	<?php
}
?>





SECONDO FILE---------------------------------------------------------------------------------------------------------------------------
accesso.php
---------------------------------------------------------------------------------------------------------------------------------------


	<?php
	include('core.php');
		if (isset($_POST['login'])) {

			$username=isset($_POST['username']);

			$password=isset($_POST['password']);



			if(empty($username) || empty($password)){
				echo 'Riempi tutti i campi! <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			elseif (mysql_num_rows(mysql_query("SELECT * FROM users WHERE username LIKE '$username' ")) == 0) {
				echo 'Username non trovato! <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			elseif (strlen($username) > 16) {
				echo 'Username troppo grande! Massimo 16 caratteri. <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			elseif (strlen($password) < 6 && strlen($password) > 20) {
				echo 'Lunghezza password non valida! <br /> Minimo 6 caratteri. <br /> Massimo 20 caratteri. <br /><br /> <a href="javascript:history.back();">Indietro</a>';
			}
			else{ $password= md5($password);
				if (mysql_num_rows(mysql_query("SELECT * FROM users WHERE username LIKE '$username' AND password='$password'"))> 0){
					$username = mysql_result(mysql_query("SELECT * FROM users WHERE username LIKE '$username'"), 0);
					$_SESSION['username']=$username;
					header('Location: text.php');
				}

			 {
					echo "Accesso andato a buon fine!";
				}
		}


		}else{
	?>

			<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="POST">
				<label>Username: <input type="text" name="username" required maxlength="16"> </label><br>
				<label>Password: <input type="password" name="password" required maxlength="20" pattern="(\s*(\S)\s*){6,20}"> </label><br>
				<input type="submit" name="login" value="Accedi">
			</form>
	<?php
}
?>




TERZO FILE-----------------------------------------------------------------------------------------------------------------------------
text.php
---------------------------------------------------------------------------------------------------------------------------------------
<?php
	include('core.php');


	if (isset($_SESSION['username'])) {
		echo "Bentornato".$_SESSION['username'];
	}
	else{	header('Location: accesso.php');}
?>