XCode Project Portfile Question

[Altoine Barker]

I'm trying to build a Portfile based off of an xcode project but I
need to ask a few questions.

1. How do you build -alltargets like this command example:
    xcodebuild -project myProject -alltargets

2. How do you include cmake commands in a portfile like the following
example:
    cmake
-DPYTHON_INC=/opt/local/Library/Frameworks/Python.framework/Versions/3.1/include/python3.1
-G Xcode ../myProject

3. How do you detect an arch and include it in a Portfile made for an
xcode project?

4. Will this be made further complex by pulling the source from an svn
source?

I apologize for disturbing you all but I have read all over the place
and before I dive in and start doing the ol' trial and error, I had
hoped that I could avoid the arduous process of reinventing the wheel
if avoidable.  TIA

-Altoine