<?php
/*
 * Protect uploaded files with login.
 *
 * dl-file.php
 * Block access to all files except images.
 *
 * Add file dl-file.php to root Wordpress
 * Add two line on .htaccess: 	
 *				RewriteCond %{REQUEST_FILENAME} -s
 * 				RewriteRule ^wp-content/uploads/(.*)$ dl-file.php?file=$1 [QSA,L]
 *
 * @link http://wordpress.stackexchange.com/questions/37144/protect-wordpress-uploads-if-user-is-not-logged-in
 * @old file https://gist.github.com/hakre/1552239
 * 
 * @author hakre <http://hakre.wordpress.com/>
 * @edit trongcong <https://2dev4u.com/>
 * @license GPL-3.0+
 * @registry SPDX
 */

class yourFun {
	function _read_file( $mimetype, $file ) {
		header( 'Content-Type: ' . $mimetype ); // always send this
		if ( false === strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS' ) ) {
			header( 'Content-Length: ' . filesize( $file ) );
		}
		$last_modified = gmdate( 'D, d M Y H:i:s', filemtime( $file ) );
		$etag          = '"' . md5( $last_modified ) . '"';
		header( "Last-Modified: $last_modified GMT" );
		header( 'ETag: ' . $etag );
		header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', time() + 100000000 ) . ' GMT' );
		// Support for Conditional GET
		$client_etag = isset( $_SERVER['HTTP_IF_NONE_MATCH'] ) ? stripslashes( $_SERVER['HTTP_IF_NONE_MATCH'] ) : false;
		if ( ! isset( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
			$_SERVER['HTTP_IF_MODIFIED_SINCE'] = false;
		}
		$client_last_modified = trim( $_SERVER['HTTP_IF_MODIFIED_SINCE'] );
		// If string is empty, return 0. If not, attempt to parse into a timestamp
		$client_modified_timestamp = $client_last_modified ? strtotime( $client_last_modified ) : 0;
		// Make a timestamp for our most recent modification...
		$modified_timestamp = strtotime( $last_modified );
		if ( ( $client_last_modified && $client_etag )
			? ( ( $client_modified_timestamp >= $modified_timestamp ) && ( $client_etag == $etag ) )
			: ( ( $client_modified_timestamp >= $modified_timestamp ) || ( $client_etag == $etag ) )
		) {
			status_header( 304 );
			exit;
		}
		// If we made it this far, just serve the file
		readfile( $file );
	}
}

$fun = new yourFun();
require_once( 'wp-load.php' );

list( $basedir ) = array_values( array_intersect_key( wp_upload_dir(), array( 'basedir' => 1 ) ) ) + array( null );
$file = rtrim( $basedir, '/' ) . '/' . str_replace( '..', '', isset( $_GET['file'] ) ? $_GET['file'] : '' );
if ( ! $basedir || ! is_file( $file ) ) {
	status_header( 404 );
	die( '404 &#8212; File not found.' );
}

$mime = wp_check_filetype( $file );
if ( false === $mime['type'] && function_exists( 'mime_content_type' ) ) {
	$mime['type'] = mime_content_type( $file );
}
if ( $mime['type'] ) {
	$mimetype = $mime['type'];
} else {
	$mimetype = 'image/' . substr( $file, strrpos( $file, '.' ) + 1 );
}

//var_dump(is_array(getimagesize($file)));
//die();

if ( is_user_logged_in() ) {
	$fun->_read_file( $mimetype, $file );
} elseif ( ! is_user_logged_in() && is_array( getimagesize( $file ) ) ) {
	$fun->_read_file( $mimetype, $file );
} elseif ( ! is_user_logged_in() && ! is_array( getimagesize( $file ) ) ) {
	auth_redirect();
}