<?php

    /**
    *   Connect to DB
    */

    $host = "localhost";
    $user = "root";
    $pass = "";
    $dbname = "content";

    try {

        $conn = new PDO("mysql:host=$host;dbname=$dbname", $user, $pass);

        $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    }

    catch(PDOException $e) {

        echo "Connection failed: " . $e->getMessage();

    }


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

        $username = trim($_POST['user']);

        /**
        *   Set error to empty in the beginning...
        */

        $error = '';

        /**
        *   Example of form validation...
        */

        if(empty($username)) {

            $error = "You must enter a username.";

        }

        /**
        *   If the error is still empty, we can go ahead
        *   and run our query...
        */

        if($error == '') {

            $sql = "SELECT * FROM users WHERE username = :username";

            $stmt = $conn->prepare($sql);

            $stmt->bindParam(":username", $username, PDO::PARAM_STR);

            $stmt->execute();

            //var_dump($stmt->execute());

            if($stmt->rowCount() > 0) {

                $error = "That user name is taken...";

            } else {

                $error = "Username is not taken...";

            }

        }

        $data = array(

            'error'  => $error

        );

        echo json_encode($data);

    } else {

        die("Cannot access this file directly...");

    }

?>