<?php
// @codingStandardsIgnoreStart
/*
UpdraftPlus Addon: lockadmin:Password-protect the UpdraftPlus Settings Screen
Description: Provides the ability to lock the UpdraftPlus settings with a password
Version: 1.3
Shop: /shop/lockadmin/
Latest Change: 1.14.3
*/
// @codingStandardsIgnoreEnd

if (!defined('UPDRAFTPLUS_DIR')) die('No direct access allowed');

if (defined('UPDRAFTPLUS_NOADMINLOCK') && UPDRAFTPLUS_NOADMINLOCK) return;

$GLOBALS['updraftplus_addon_lockadmin'] = new UpdraftPlus_Addon_LockAdmin;

class UpdraftPlus_Addon_LockAdmin {

	private $correct_password_supplied = null;

	private $default_support_url = 'https://updraftplus.com/faqs/locked-updraftplus-settings-page-forgotten-password-unlock/';

	/**
	 * Password set by user for locking UpdraftPlus settings page.
	 *
	 * @var string
	 */
	private $old_password = '';

	/**
	 * Length of $this->opts['password'].
	 *
	 * @var int
	 */
	private $password_length = 0;

	/**
	 * Stores password, session and other data
	 *
	 * @var Array
	 */
	private $opts;

	/**
	 * Constructor
	 */
	public function __construct() {
		add_filter('updraftplus_settings_page_render', array($this, 'settings_page_render'));
		add_action('updraftplus_settings_page_render_abort', array($this, 'settings_page_render_abort'));
		if ((!empty($_POST['updraft_unlockadmin_session_length']) || !empty($_POST['updraft_unlockadmin_password'])) && !empty($_POST['nonce'])) add_action('admin_init', array($this, 'admin_init'));
		add_action('updraftplus_debugtools_dashboard', array($this, 'debugtools_dashboard'), 10);
	}

	private function check_user_cookie($password) {
		if (empty($password)) return true;
		// Value in seconds
		$session_length = $this->opts['session_length'];
		if (!$session_length) $session_length = 86400;

		// A lock has been set. Has the user passed the test?
		if (empty($_COOKIE['updraft_unlockadmin'])) return false;

		// Cookie in correct format?
		if (!preg_match('/^(\d+):(.*)$/', $_COOKIE['updraft_unlockadmin'], $matches)) return false;

		$cookie_time = $matches[1]; // The time when the session began
		$cookie_hash = $matches[2];

		$time_now = time();

		// Cookie is older than session length
		if ($time_now > $cookie_time + $session_length) return false;

		$cookie_session_began = $cookie_time - ($cookie_time % $session_length);

		$user = wp_get_current_user();
		if (!is_a($user, 'WP_User')) return false;

		// The cookie relies on the user ID, password and session time. So, someone stealing the cookie can't use it forever. They need the password to generate valid cookies.
		$correct_hash = hash('sha256', $user->ID.'-'.$password.'-'.$cookie_session_began);

		if ($correct_hash != $cookie_hash) return false;

		return true;
	}

	public function return_opts() {
		$this->get_opts();
		return $this->opts;
	}

	/**
	 * Get standard session length options
	 *
	 * @return array Session length options with values and labels
	 */
	public function get_session_length_options() {
		return array(
			'3600' => __('1 hour', 'updraftplus'),
			'10800' => sprintf(__('%s hours', 'updraftplus'), 3),
			'86400' => sprintf(__('%s hours', 'updraftplus'), 24),
			'604800' => __('1 week', 'updraftplus'),
			'2419200' => sprintf(__('%s weeks', 'updraftplus'), 4),
			'31449600' => sprintf(__('%s weeks', 'updraftplus'), 52)
		);
	}

	private function get_opts() {
		$this->opts = UpdraftPlus_Options::get_updraft_option('updraft_adminlocking');
		if (!is_array($this->opts)) $this->opts = array();
		if (!isset($this->opts['password'])) $this->opts['password'] = '';
		if (!isset($this->opts['session_length'])) $this->opts['session_length'] = 3600;
		if (!isset($this->opts['support_url'])) $this->opts['support_url'] = '';
	}

	/**
	 * Runs upon the WP action admin_init, but only if there's appropriate data in $_POST
	 */
	public function admin_init() {
	
		if ((empty($_POST['updraft_unlockadmin_session_length']) && empty($_POST['updraft_unlockadmin_password'])) || empty($_POST['nonce'])) return;
		
		if (!wp_verify_nonce($_POST['nonce'], 'updraftplus-unlockadmin-nonce')) return;
		
		$user = wp_get_current_user();
		if (!is_a($user, 'WP_User')) return;
		
		$this->get_opts();
		
		if (!empty($_POST['updraft_unlockadmin_session_length']) && isset($_POST['updraft_unlockadmin_oldpassword']) && $_POST['updraft_unlockadmin_oldpassword'] == $this->opts['password']) {
			$this->old_password = $this->opts['password'];
			$this->opts['password'] = $_POST['updraft_unlockadmin_password'];
			$this->opts['support_url'] = $_POST['updraft_unlockadmin_support_url'];
			$this->opts['session_length'] = (int) $_POST['updraft_unlockadmin_session_length'];
			UpdraftPlus_Options::update_updraft_option('updraft_adminlocking', $this->opts);
			$this->password_length = strlen($this->opts['password']);
			add_action('all_admin_notices', array($this, 'show_admin_warning_passwordset'));
		}
		
		// Note: this code also fires when the user sets a new password (because we don't want to immediately lock them)
		$password = $this->opts['password'];
		if ($password === (string) $_POST['updraft_unlockadmin_password']) {
			$session_length = (int) $this->opts['session_length'];
			if ($session_length<1) $session_length = 86400;
			// The cookie relies on the user ID, password and session time. So, someone stealing the cookie can't use it forever. They need the password to generate valid cookies.
			$time_now = time();
			$expire = $time_now + $session_length;
			$cookie_session_began = $time_now - ($time_now % $session_length);
			$correct_hash = hash('sha256', $user->ID.'-'.$password.'-'.$cookie_session_began);
			$secure = apply_filters('secure_auth_cookie', is_ssl(), $user->ID);
			setcookie('updraft_unlockadmin', $cookie_session_began.':'.$correct_hash, $expire, ADMIN_COOKIE_PATH, COOKIE_DOMAIN, $secure, true);
			$this->correct_password_supplied = true;
		} else {
			$this->correct_password_supplied = false;
		}
	}

	public function show_admin_warning_passwordset() {
		$msg = '<strong>';
		if (strlen($this->old_password) >0 && 0 == $this->password_length) {
			$msg .= __('The admin password has now been removed.', 'updraftplus');
		} elseif (strlen($this->old_password) == 0 && $this->password_length > 0) {
			$msg .= __('An admin password has been set.', 'updraftplus');
		} elseif ($this->old_password !== $this->opts['password']) {
			$msg .= __('The admin password has been changed.', 'updraftplus');
		} else {
			$msg .= __('Settings saved.');
		}
		$msg .= '</strong>';
		global $updraftplus_admin;
		$updraftplus_admin->show_admin_warning($msg);
	}

	public function settings_page_render($go) {
		if (!$go) return $go;
		if ($this->correct_password_supplied) return true;
		$this->get_opts();
		$password = $this->opts['password'];
		if ($this->check_user_cookie($password)) return $go;
		return false;
	}

	/**
	 * Runs upon the WP action updraftplus_debugtools_dashboard
	 */
	public function debugtools_dashboard() {
		global $updraftplus_admin;
		$this->get_opts();
		?>
		<div class="advanced_tools lock_admin">
			<h3>
				<?php esc_html_e('Lock access to the UpdraftPlus settings page', 'updraftplus'); ?>
			</h3>
			<p>
				<a href="https://teamupdraft.com/documentation/updraftplus/premium-features/how-to-lock-updraftplus-settings/?utm_source=udp-plugin&utm_medium=referral&utm_campaign=paac&utm_content=read-about-lock-settings&utm_creative_format=tex" target="_blank">
					<em><?php esc_html_e('Read more about how this works...', 'updraftplus');?></em>
				</a>
			</p>
			<form id="lock_form" method="post" onsubmit="if (jQuery('#updraft_unlockadmin_password').val() != '') { return(confirm('<?php echo esc_js(__('Please make sure that you have made a note of the password!', 'updraftplus'));?>')); } else { return true; }">
				<input type="hidden" name="nonce" value="<?php echo esc_attr(wp_create_nonce('updraftplus-unlockadmin-nonce'));?>">
				<input type="hidden" name="page" value="updraftplus">
				<input type="hidden" name="tab" value="expert">
				<input id="updraft_unlockadmin_oldpassword" type="hidden" name="updraft_unlockadmin_oldpassword" value="<?php echo esc_attr($this->opts['password']);?>">
				<table>
				<?php

					$updraftplus_admin->settings_debugrow('<label for="updraft_unlockadmin_password">'.esc_html__('Password', 'updraftplus').'</label>:', '<input type="text" id="updraft_unlockadmin_password" name="updraft_unlockadmin_password" value="'.esc_attr($this->opts['password']).'" style="width:230px;">');

					$session_lengths = $this->get_session_length_options();

					$session_options = '';
					foreach ($session_lengths as $length => $text) {
					$session_options .= "<option value=\"$length\"".(($this->opts['session_length'] == $length) ? ' selected="selected"' : '').">".htmlspecialchars($text)."</option>\n";
					}

					$updraftplus_admin->settings_debugrow('<label for="updraft_unlockadmin_session_length">'.esc_html__('Require password again after', 'updraftplus').'</label>:', '<select id="updraft_unlockadmin_session_length" name="updraft_unlockadmin_session_length" style="width:230px;">'.$session_options.'</select>');

					$updraftplus_admin->settings_debugrow('<label for="updraft_unlockadmin_support_url">'.esc_html__('Support URL', 'updraftplus').'</label>:', '<input id="updraft_unlockadmin_support_url" name="updraft_unlockadmin_support_url" type="'.apply_filters('updraftplus_admin_secret_field_type', 'text').'" value="'.esc_attr($this->opts['support_url']).'" style="width:230px;"><br><em>'.esc_html__('Anyone seeing the lock screen will be shown this URL for support - enter a website address or an email address.', 'updraftplus').' <a target="_blank" href="'.$this->default_support_url.'">'.esc_html__('Otherwise, the default link will be shown.', 'updraftplus').'</a></em>');

					$updraftplus_admin->settings_debugrow('', '<input class="button-primary change_lock_settings" type="submit" value="'.esc_attr(__('Change Lock Settings', 'updraftplus')).'">');
					?>
				</table>
			</form>
		</div>
	<?php
	}

	public function settings_page_render_abort() {
		global $updraftplus_admin;
		$updraftplus_admin->settings_header();

		?>
		<style type="text/css">
			#updraft-lock-area {
				border: 4px dashed #ddd;
				height: 320px;
				margin: 36px 0 0 20px;
				width: 650px;
			}
			#updraft-lock-area p {
				font-size: 16px;
				text-align: center;
			}

		</style>
		<div id="updraft-lock-area">
			<p>
				<img width="150" height="150" src="<?php echo esc_url(UPDRAFTPLUS_URL);?>/images/padlock-150.png" alt="<?php echo esc_attr(__('Unlock', 'updraftplus'));?>">
			</p>
			<form method="post">
			<input type="hidden" name="nonce" value="<?php echo esc_attr(wp_create_nonce('updraftplus-unlockadmin-nonce'));?>">
			<p>
				<input type="password" size="16" name="updraft_unlockadmin_password" value="">
				<input type="submit" value="<?php echo esc_attr(__('Unlock', 'updraftplus'));?>">
			</p>
			</form>
			<p>
				<?php
					if (false === $this->correct_password_supplied) {
					echo '<span style="color:red;">'.esc_html__('Password incorrect', 'updraftplus').'</span><br>';
					}
				?>
				<?php esc_attr_e('To access the UpdraftPlus settings, please enter your unlock password', 'updraftplus'); ?><br>
				<span style="font-size:85%;"><em>
					<?php
						$this->get_opts();
						$url = empty($this->opts['support_url']) ? $this->default_support_url : $this->opts['support_url'];
						if (preg_match('/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i', $url)) $url = 'mailto:'.$url;
						if (!empty($url)) {
							echo '<a href="'.esc_attr($url).'">';
						}
						esc_attr_e('For unlocking support, please contact whoever manages UpdraftPlus for you.', 'updraftplus');
						if (!empty($url)) {
							echo '</a>';
						}
					?>
				</em></span>
			</p>
			
		</div>
		<?php
		// settings_header opens a div
		echo '</div>';
	}
}
