Version-controlling zipped files (docx, odt)

There are formats that are actually zip files in disguise, e.g. docx or odt. If I store them directly in version control, they are handled as binary files. My ideal solution would be

• have a hook that creates a foo.docx/ directory for each foo.docx files before commit, unzipping all files into it
• optionally, have a hook that reindents the xml files
• have a hook that recreates foo.docx from the stored files after update

I don't want the docx files themselves to be version-controlled. (I am aware of a related question where a different approach with a custom diff was suggested.)

Is this doable? Is this doable with mercurial?

UPDATE:

I know about hooks. I am interested in the specifics. Here is a session to demonstrate the expected behavior.

> hg add foo.docx
> hg status
A foo.docx
> hg commit
> # Change foo.docx with external editor
> hg status
M foo.docx
> hg diff
+++ foo.docx/word/document.xml
- <w:t>An idea</w:t>
+ <w:t>A much better idea</w:t>