Regular expression to parse JSON

[jabi]

I need help with writing regular expression for this pattern in PHP:\[code\][[{"type":"media","view_mode":"small","fid":"1","attributes":{"width":0,"height":0,"src":"http://localhost/x.png"}}]]\[/code\]This is part of the text and I am trying to replace this by something else.Would like to use \[code\]preg_replace_all()\[/code\] but can't figure out what would be the pattern. Any help appreciated.