How Can I convert URL like "www.site.com" or like "http://www.site.com" to "(url)http://www.site.com(/url)"

Provide that : there is at least one space before and after url.

for example(s):
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$text="go here http://www.anysite.com please";

output:
$text="go here (url)http://www.anysite.com(/url) please";


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$text="go here (http://www.anysite.com please";

output:
$text="go here (http://www.anysite.com please";

no effect because there is no any spaces befor url.




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