require 'formula'

class Py2cairo < Formula
  homepage 'http://cairographics.org/pycairo/'
  url 'http://cairographics.org/releases/py2cairo-1.10.0.tar.bz2'
  md5 '20337132c4ab06c1146ad384d55372c5'

  depends_on 'cairo'
  depends_on :x11

  fails_with :llvm do
    build 2336
    cause "The build script will set -march=native which llvm can't accept"
  end

  def options
    [['--universal', 'Build universal binaries']]
  end

  def install
    # Python extensions default to universal but cairo may not be universal
    unless ARGV.build_universal?
      ENV['ARCHFLAGS'] = if MacOS.prefer_64_bit?
        "-arch x86_64"
      else
        "-arch i386"
      end
    end

    # waf miscompiles py2cairo on Lion, linking the wrong Python Library when
    # HB Python is installed.  So add a LINKFLAG that sets the path to the real
    # python Library as determined by `python-prefix`, where it gets used at
    # link time and fixes the problem where you can't import cairo into Python.
    # https://github.com/mxcl/homebrew/issues/12893
    # https://bugs.freedesktop.org/show_bug.cgi?id=51544
    ENV['LINKFLAGS'] = "-L#{%x(python-config --prefix).chomp}/lib"
    system "./waf", "configure", "--prefix=#{prefix}", "--nopyc", "--nopyo"
    system "./waf", "install"
  end

  def caveats; <<-EOS.undent
    For non-homebrew Python, you need to amend your PYTHONPATH like so:
      export PYTHONPATH=#{HOMEBREW_PREFIX}/lib/#{which_python}/site-packages:$PYTHONPATH
    EOS
  end

  def which_python
    "python" + `python -c 'import sys;print(sys.version[:3])'`.strip
  end
end