<?php
/**
* Copyright © Magento, Inc. All rights reserved.
* See COPYING.txt for license details.
*/

namespace Magento\Framework\File;

/**
* Utility for mime type retrieval
*/
class Mime
{
/**
* Mime types
*
* @var array
*/
protected $mimeTypes = [
'txt' => 'text/plain',
'htm' => 'text/html',
'html' => 'text/html',
'php' => 'text/html',
'css' => 'text/css',
'js' => 'application/javascript',
'json' => 'application/json',
'xml' => 'application/xml',
'swf' => 'application/x-shockwave-flash',
'flv' => 'video/x-flv',

// images
'png' => 'image/png',
'jpe' => 'image/jpeg',
'jpeg' => 'image/jpeg',
'jpg' => 'image/jpeg',
'gif' => 'image/gif',
'bmp' => 'image/bmp',
'ico' => 'image/vnd.microsoft.icon',
'tiff' => 'image/tiff',
'tif' => 'image/tiff',
'svg' => 'image/svg+xml',
'svgz' => 'image/svg+xml',

// archives
'zip' => 'application/zip',
'rar' => 'application/x-rar-compressed',
'exe' => 'application/x-msdownload',
'msi' => 'application/x-msdownload',
'cab' => 'application/vnd.ms-cab-compressed',

// audio/video
'mp3' => 'audio/mpeg',
'qt' => 'video/quicktime',
'mov' => 'video/quicktime',

// adobe
'pdf' => 'application/pdf',
'psd' => 'image/vnd.adobe.photoshop',
'ai' => 'application/postscript',
'eps' => 'application/postscript',
'ps' => 'application/postscript',
];

/**
* List of mime types that can be defined by file extension.
*
* @var array
*/
private $defineByExtensionList = [
'txt' => 'text/plain',
'htm' => 'text/html',
'html' => 'text/html',
'php' => 'text/html',
'css' => 'text/css',
'js' => 'application/javascript',
'json' => 'application/json',
'xml' => 'application/xml',
'svg' => 'image/svg+xml',
];

/**
* List of generic MIME types
*
* The file mime type should be detected by the file's extension if the native mime type is one of the listed below.
*
* @var array
*/
private $genericMimeTypes = [
'application/x-empty',
'inode/x-empty',
];

/**
* Get mime type of a file
*
* @param string $file
* @return string
* @throws \InvalidArgumentException
*/
public function getMimeType($file)
{
if (!file_exists($file)) {
throw new \InvalidArgumentException("File '$file' doesn't exist");
}

$result = null;
$extension = $this->getFileExtension($file);

if (function_exists('mime_content_type')) {
$result = $this->getNativeMimeType($file);
}

if (null === $result && isset($this->mimeTypes[$extension])) {
$result = $this->mimeTypes[$extension];
} elseif (null === $result) {
$result = 'application/octet-stream';
}

return $result;
}

/**
* Get mime type by the native mime_content_type function.
*
* Search for extended mime type if mime_content_type() returned 'application/octet-stream' or 'text/plain'
*
* @param string $file
* @return string
*/
private function getNativeMimeType(string $file): string
{
$extension = $this->getFileExtension($file);
$result = mime_content_type($file);
if (isset($this->mimeTypes[$extension], $this->defineByExtensionList[$extension])
&& (
strpos($result, 'text/') === 0
|| strpos($result, 'image/svg') === 0
|| in_array($result, $this->genericMimeTypes, true)
)
) {
$result = $this->mimeTypes[$extension];
}

return $result;
}

/**
* Get file extension by file name.
*
* @param string $file
* @return string
*/
private function getFileExtension(string $file): string
{
return strtolower(pathinfo($file, PATHINFO_EXTENSION));
}
}