从S3 URL中提取存储桶和资源名称（正则表达式问题）

I will be receiving input which will be ANY ONE of the following. I need to devise a regex which can handle any of these and extract the validS3bucketname and validS3resourcename.

http://s3.amazonaws.com/validS3bucketname/validS3resourcename
https://s3.amazonaws.com/validS3bucketname/validS3resourcename
http://validS3bucketname.s3.amazonaws.com/validS3resourcename
https://validS3bucketname.s3.amazonaws.com/validS3resourcename

validS3bucketname and validS3resourcename are VALID S3 values, including spaces and whatever not - I have no idea what S3 allows as valid file names.

The following will match both:

/:\/\/s3\.amazonaws.com\/([^\/]+)|:\/\/([^.]+)\.s3\.amazonaws\.com\//

this simple function should wrap it nicely

function getS3Info($url) {
    if(! preg_match('/(?:\/\/s3\.amazonaws.com\/([^\/]+)|:\/\/([^.]+)\.s3\.amazonaws\.com)\/([^\/]+)/', $url, $a)) {
        return false;
    }

    $bucket = isset($a[2]) ? $a[2] : $a[1];
    $resource = $a[3];

    return array('bucket' => $bucket, 'resource' => $resource);
}

Maybe these can be combined. Take it as inspiration:

First case:

^https?://s3\.amazonaws\.com\/([^/]+)/(.+)$

Second case:

^https?://([^/]+)\.s3\.amazonaws\.com\/(.+)$