Payment Terms from supplier invoice date

Hello

We follow ERS method to create invoice on supplier. Negotiated terms get defaulted on invoice from Purchase Order. But invoice date the date on which receipt is made. We would like to know if there is any set up or field by which one can capture supplier invoice date and calculate payment terms from that date. (Even calculation from the date of ASN would also be fine)

Example,

Supplier invoice date     1-Jul-14

ASN date                     1-Jul-14

Receipt date                 5-Jul-14

Terms                          7 Days

Invoice Date                  5-Jul-14

Delay in payment         12-Jul-14

Regards

G1