login.php

<?php
require_once $_SERVER['DOCUMENT_ROOT'].'/tutorial/core/init.php';
include 'includes/head.php';

$email = ((isset($_POST['email']))?sanitize($_POST['email']):'');
$email = trim($email);
$password = ((isset($_POST['password']))?sanitize($_POST['password']):'');
$password = trim($password);
$errors = array();
?>
<style type="text/css">
body{
    background-image : url("/tutorial/images/headerlogo/background.png");
    background-size : 100vw 100vh;
    background-attachment: fixed;
}
</style>
<div id="login-form">
    <div>

        <?php
        if ($_POST) {

            # validasi Form
            if (empty($_POST['email']) || empty($_POST['password'])) {
                $errors[] = 'Kolom email dan password harus diisi';
            }

            # validasi email
            if (!filter_var($email,FILTER_VALIDATE_EMAIL)) {
                $errors[] = 'Tolong ketikkan email yang valid';
            }

            #jika password kurang dari 6
            if (strlen($password) < 6) {
                $errors[] = 'Password tidak boleh kurang dari 6 huruf';
            }

            # cek email jika sudah ada didalam database
            $query = $db->query("SELECT * FROM users WHERE email = '$email'");
            $user = mysqli_fetch_assoc($query);
            $hitung = mysqli_num_rows($query);
            if ($hitung < 1) {
                $errors[] = 'Email yang anda masukan salah!';
            }

            if (!password_verify($password,$user['password'])) {
                $errors[] = 'Password yang anda masukan salah!';
            }

            # cek kesalahan
            if (!empty($errors)) {
                echo display_errors($errors);
            }else{
                #jika semua verifikasi sudah dilewati
                $user_id = $user['id'];
                login($user_id);
            }

        }
        ?>

    </div>
    <h2 class="text-center">Login</h2>
    <form action="login.php" method="post">
        <div class="form-group">
            <label for="email">Email :</label>
            <input type="text" name="email" class="form-control" id="email" value="<?=$email;?>">
        </div>
        <div class="form-group">
            <label for="password">Password :</label>
            <input type="password" name="password" class="form-control" id="password" value="<?=$password?>">
        </div>
        <div class="form-group">
            <input type="submit" class="btn btn-primary" name="name" value="Login">
        </div>
    </form>
    <p class="text-right"><a href="/tutorial/index.php">Visit Site</a></p>
</div>

<footer class="text-center" id="footeristik">&copy; Copyright 2016 Shauntas's Boutique, Created By : Restu Haerul Z.</footer>