APEX

Hi,
I am trying to write my own pl/sql procedure to export Interactive Report into excel and email to an alias. I kind of figured out how to create excel file
using XML and also know how to send that by email. My problem is there can be multiple worksheets in a Interactive report and I need to export only the current worksheet. How will I know what is my current worksheet. I am sure there is some substitution variable or other mechanism to do this. Please help.

Note : I can find my report ID by looking at #REGION_ID# substituion string and from there I need to find out the current worksheet ID number.
Any help on this is highly appreciated.

Thanks
Karthik