Change layout of default calendar

Hi all,

I hope someone out there can help me with this little snippet of code. I wish to alter the layout of the default WordPress calendar by altering the table. This link shows how I’d like it to look.

I’ve found the part of the get_calendar function that needs changing, but I can’t figure out how I need to change it. Basically for the first 3 rows, after 4 colums, I need to initiate a new row. The for the following rows there will be 7 columns.

[Code moderated as per the Forum Rules. Please use the pastebin]

Can anyone give me a hint about how to accomplish this? Any response will be greatly appreciated.

Many thanks,
Amal