<?php
// Include config file
require_once 'config.php';

// Define variables and initialize with empty values
$username = $password = "";
$failed_logins = 0;
$username_err = $password_err = "";

// Processing form data when form is submitted
if($_SERVER["REQUEST_METHOD"] == "POST"){
  //basic CSRF protection, verifying http origin header
  #if (isset($_SERVER["HTTP_ORIGIN"])) {
  #      $address = "https://".$_SERVER["SERVER_NAME"];
  #      if (strpos($address, $_SERVER["HTTP_ORIGIN"]) !== 0) {
  #          exit("CSRF protection in POST request: detected invalid Origin header: ".$_SERVER["HTTP_ORIGIN"]);
  #      }
  #  }
    // Check if username is empty
    if(empty(trim($_POST["username"]))){
        $username_err = 'Please enter username.';
    } else{
        $username = trim($_POST["username"]);
    }

    // Check if password is empty
    if(empty(trim($_POST['password']))){
        $password_err = 'Please enter your password.';
    } else{
        $password = trim($_POST['password']);
    }
    #echo $username;
    #echo $password;
    $sql = "SELECT username, password, failed_logins FROM users WHERE username = $username";
    $row = mysqli_query($link, $sql);
    echo $row;


  /*
    // Validate credentials
    if(empty($username_err) && empty($password_err)){
        // Prepare a select statement
        $sql = "SELECT username, password, failed_logins FROM users WHERE username = ?";

        if($stmt = mysqli_prepare($link, $sql)){
            // Bind variables to the prepared statement as parameters
            mysqli_stmt_bind_param($stmt, "s", $param_username);

            // Set parameters
            $param_username = $username;

            // Attempt to execute the prepared statement
            if(mysqli_stmt_execute($stmt)){
                // Store result
                mysqli_stmt_store_result($stmt);

                // Check if username exists, if yes then verify password
                if(mysqli_stmt_num_rows($stmt) == 1){
                    // Bind result variables
                    mysqli_stmt_bind_result($stmt, $username, $hashed_password, $failed_logins);
                    if(mysqli_stmt_fetch($stmt)){
                        if($failed_logins > 4) {
                            echo "You have too many failed attempts and your account is now locked";
                        } elseif(password_verify($password, $hashed_password)){
                            #Password is correct, so start a new session and
                            #save the username to the session. Failed logins is set to 0
                            $sql2 = "UPDATE users SET failed_logins=? WHERE username=?";
                            if($stmt2 = mysqli_prepare($link, $sql2)){
                                // Bind variables to the prepared statement as parameters
                                mysqli_stmt_bind_param($stmt2, "is", $param_failed, $param_username);
                                // Set parameters
                                $param_failed = 0;
                                // Attempt to execute the prepared statement
                                if(mysqli_stmt_execute($stmt2)){
                                // Redirect to login page
                                header("location: login.php");
                                } else{
                                 echo "Something went wrong. Please try again later.";
                                }
                            }
                            // Close statement
                            mysqli_stmt_close($stmt2);
                            session_start();
                            $_SESSION['username'] = $username;
                            header("location: welcome.php");
                        } else{
                            // Display an error message if password is not valid
                            $sql2 = "UPDATE users SET failed_logins=? WHERE username=?";
                            if($stmt2 = mysqli_prepare($link, $sql2)){
                                // Bind variables to the prepared statement as parameters
                                mysqli_stmt_bind_param($stmt2, "is", $param_failed, $param_username);
                                // Set parameters
                                $param_failed = $failed_logins + 1;
                                // Attempt to execute the prepared statement
                                if(!mysqli_stmt_execute($stmt2)){
                                 echo "Something went wrong. Please try again later.";
                                }
                            }
                            // Close statement
                            mysqli_stmt_close($stmt2);
                            $password_err = 'The password you entered was not valid.';
                        }
                    }
                } else{
                    // Display an error message if username doesn't exist
                    $username_err = 'No account found with that username.';
                }
            } else{
                echo "Oops! Something went wrong. Please try again later.";
            }
        }

        // Close statement
        mysqli_stmt_close($stmt);
    }
*/
    // Close connection
    mysqli_close($link);
}
?>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Login</title>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.css">
    <style type="text/css">
        body{ font: 14px sans-serif; }
        .wrapper{ width: 350px; padding: 20px; }
    </style>
</head>
<body>
    <div class="wrapper">
        <h2>SQLogin</h2>
        <p>Please fill in your credentials to login.</p>
        <form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
            <div class="form-group <?php echo (!empty($username_err)) ? 'has-error' : ''; ?>">
                <label>Username:<sup>*</sup></label>
                <input type="text" name="username"class="form-control" value="<?php echo $username; ?>">
                <span class="help-block"><?php echo $username_err; ?></span>
            </div>
            <div class="form-group <?php echo (!empty($password_err)) ? 'has-error' : ''; ?>">
                <label>Password:<sup>*</sup></label>
                <input type="password" name="password" class="form-control">
                <span class="help-block"><?php echo $password_err; ?></span>
            </div>
            <div class="form-group">
                <input type="submit" class="btn btn-primary" value="Submit">
            </div>
            <p>Don't have an account? <a href="register.php">Sign up now</a>.</p>
        </form>
    </div>
</body>
</html>