require 'formula'

class Go < Formula
  homepage 'http://golang.org'
  url 'http://go.googlecode.com/files/go1.0.3.src.tar.gz'
  version '1.0.3'
  sha1 '1a67293c10d6c06c633c078a7ca67e98c8b58471'
  head 'https://go.googlecode.com/hg/'

  skip_clean 'bin'

  option 'cross-compile-all', "Build the cross-compilers and runtime support for all supported platforms"
  option 'cross-compile-common', "Build the cross-compilers and runtime support for darwin, linux and windows"

  if build.head?
    fails_with :clang do
      cause "clang: error: no such file or directory: 'libgcc.a'"
    end
  end

  def install
    # install the completion scripts
    (prefix/'etc/bash_completion.d').install 'misc/bash/go' => 'go-completion.bash'
    (share/'zsh/site-functions').install 'misc/zsh/go' => '_go'

    if build.include? 'cross-compile-all'
      targets = [
        ['linux',   ['386', 'amd64', 'arm'], { :cgo => false }],
        ['freebsd', ['386', 'amd64'],        { :cgo => false }],

        ['openbsd', ['386', 'amd64'],        { :cgo => false }],

        ['windows', ['386', 'amd64'],        { :cgo => false }],

        # Host platform (darwin/amd64) must always come last
        ['darwin',  ['386', 'amd64'],        { :cgo => true  }],
      ]
    elsif build.include? 'cross-compile-common'
      targets = [
        ['linux',   ['386', 'amd64', 'arm'], { :cgo => false }],
        ['windows', ['386', 'amd64'],        { :cgo => false }],

        # Host platform (darwin/amd64) must always come last
        ['darwin',  ['386', 'amd64'],        { :cgo => true  }],
      ]
    else
      targets = [
        ['darwin', [''], { :cgo => true }]
      ]
    end

    # The version check is due to:
    # http://codereview.appspot.com/5654068
    Pathname.new('VERSION').write 'default' if build.head?

    cd 'src' do
      # Build only. Run `brew test go` to run distrib's tests.
      targets.each do |(os, archs, opts)|
      archs.each do |arch|
        ENV['GOROOT_FINAL'] = prefix
        ENV['GOOS']         = os
        ENV['GOARCH']       = arch
        ENV['CGO_ENABLED']  = opts[:cgo] ? "1" : "0"
        allow_fail = opts[:allow_fail] ? "|| true" : ""
        system "./make.bash --no-clean #{allow_fail}"
      end
      end
    end

    # cleanup ENV
    ENV.delete('GOROOT_FINAL')
    ENV.delete('GOOS')
    ENV.delete('GOARCH')
    ENV.delete('CGO_ENABLED')

    Pathname.new('pkg/obj').rmtree

    # Don't install header files; they aren't necessary and can
    # cause problems with other builds. See:
    # http://trac.macports.org/ticket/30203
    # http://code.google.com/p/go/issues/detail?id=2407
    prefix.install(Dir['*'] - ['include'])
  end

  test do
    cd "#{prefix}/src" do
      system "./run.bash", "--no-rebuild"
    end
  end
end