Google Maps API - add orientation to perimeter calculations

I would like to create a tool that allows a user enter a physical address in a search box and then uses the Google Map API to zoom in on that address and allow the user to trace the overlay of the house/building using the polygon tool similar to [login to view URL] The script would then output the area and perimeter dimensions of the polygon just like the example website does. The major addition is I also need the length of each side of the polygon listed separately along with its majority orientation ([login to view URL] just lists the total perimeter length with no orientation). For example if the coordinates for one side of the polygon were -70.995188348461,42.50482099561405 and -70.99507703678688,42.504710262267295 it would calculate the length of the line connecting the two points is 50.337 feet and the orientation is South West. This project requires some geometry skills since the Goole maps API does not provide this calculation currently. The script should be written in PHP and provide an xml or JSON output of the results. This script is going to be incorporated into another script so there is no need to have a fancy interface, I am mainly looking for it to function properly.