require 'formula'

# Reference: https://github.com/b4winckler/macvim/wiki/building
class Macvim < Formula
  homepage 'http://code.google.com/p/macvim/'
  url 'https://github.com/b4winckler/macvim/archive/snapshot-72.tar.gz'
  version '7.4-72'
  sha1 '3fb5b09d7496c8031a40e7a73374424ef6c81166'

  head 'https://github.com/b4winckler/macvim.git', :branch => 'master'

  option "custom-icons", "Try to generate custom document icons"
  option "override-system-vim", "Override system vim"

  depends_on :xcode
  depends_on 'cscope' => :recommended
  depends_on 'lua' => :optional
  depends_on 'luajit' => :optional
  depends_on :python => :recommended
  depends_on :python3 => :optional

  env :std if MacOS.version <= :snow_leopard
  # Help us! We'd like to use superenv in these environments too

  def install
    # MacVim doesn't have and required any Python package, unset PYTHONPATH.
    ENV.delete('PYTHONPATH')

    # Set ARCHFLAGS so the Python app (with C extension) that is
    # used to create the custom icons will not try to compile in
    # PPC support (which isn't needed in Homebrew-supported systems.)
    ENV['ARCHFLAGS'] = "-arch #{MacOS.preferred_arch}"

    # If building for 10.7 or up, make sure that CC is set to "clang".
    ENV.clang if MacOS.version >= :lion

    # macvim HEAD only works with the current Ruby.framework because it builds with -framework Ruby
    system_ruby = "/System/Library/Frameworks/Ruby.framework/Versions/Current/usr/bin/ruby"

    args = %W[
      --with-features=huge
      --enable-multibyte
      --with-macarchs=#{MacOS.preferred_arch}
      --enable-perlinterp
      --enable-rubyinterp
      --enable-tclinterp
      --with-ruby-command=#{system_ruby}
      --with-tlib=ncurses
      --with-compiledby=Homebrew
      --with-local-dir=#{HOMEBREW_PREFIX}
    ]

    args << "--with-macsdk=#{MacOS.version}" unless MacOS::CLT.installed?
    args << "--enable-cscope" if build.with? "cscope"

    if build.with? "lua"
      args << "--enable-luainterp"
      args << "--with-lua-prefix=#{HOMEBREW_PREFIX}"
    end

    if build.with? "luajit"
      args << "--enable-luainterp"
      args << "--with-lua-prefix=#{HOMEBREW_PREFIX}"
      args << "--with-luajit"
    end

    if build.with? "python" and build.with? "python3"
      args << "--enable-pythoninterp=dynamic" << "--enable-python3interp=dynamic"
    else
      args << "--enable-pythoninterp" if build.with? "python"
      args << "--enable-python3interp" if build.with? "python3"
    end

    # MacVim seems to link Python by `-framework Python` (instead of
    # `python-config --ldflags`) and so we have to pass the -F to point to
    # where the Python.framework is located, we want it to use!
    # Also the -L is needed for the correct linking. This is a mess but we have
    # to wait until MacVim is really able to link against different Python's
    # on the Mac. Note configure detects brewed python correctly, but that
    # is ignored.
    # See https://github.com/Homebrew/homebrew/issues/17908
    if python2 and python2.framework? and not build.with? "python3"
      ENV.prepend 'LDFLAGS', "-L#{python2.libdir} -F#{python2.framework}"
    end

    unless MacOS::CLT.installed?
      # On Xcode-only systems:
      # Macvim cannot deal with "/Applications/Xcode.app/Contents/Developer" as
      # it is returned by `xcode-select -print-path` and already set by
      # Homebrew (in superenv). Instead Macvim needs the deeper dir to directly
      # append "SDKs/...".
      args << "--with-developer-dir=#{MacOS::Xcode.prefix}/Platforms/MacOSX.platform/Developer/"
    end

    system "./configure", *args

    if build.with? "python" and build.with? "python3"
      # On 64-bit systems, we need to avoid a 32-bit Framework Python.
      # MacVim doesn't check Python while compiling.
      python do
        if MacOS.prefer_64_bit? and python.framework? and not archs_for_command("#{python.prefix}/Python").include? :x86_64
          opoo "Detected a framework Python that does not have 64-bit support built in:"
          puts <<-EOS.undent
            #{python.prefix}

            Dynamic loading Python library requires the same architecture.

            Note that a framework Python in /Library/Frameworks/Python.framework is
            the "MacPython" version, and not the system-provided version which is in:
              /System/Library/Frameworks/Python.framework
          EOS
        end
      end
      # Help vim find Python's library as absolute path.
      python do
        inreplace 'src/auto/config.mk', /-DDYNAMIC_PYTHON#{python.if3then3}_DLL=\\".*\\"/, %Q[-DDYNAMIC_PYTHON#{python.if3then3}_DLL=\'\"#{python.prefix}/Python\"\'] if python.framework?
      end
      # Force vim loading different Python on same time, may cause vim crash.
      unless python.brewed?
        opoo "You seem to have a version of Python not installed by Homebrew. Attempting to modify config.h. You may see warning message during brewing."
        inreplace 'src/auto/config.h', "/* #undef PY_NO_RTLD_GLOBAL */", "#define PY_NO_RTLD_GLOBAL 1"
        inreplace 'src/auto/config.h', "/* #undef PY3_NO_RTLD_GLOBAL */", "#define PY3_NO_RTLD_GLOBAL 1"
      end
    end

    if build.include? "custom-icons"
      # Get the custom font used by the icons
      cd 'src/MacVim/icons' do
        system "make getenvy"
      end
    else
      # Building custom icons fails for many users, so off by default.
      inreplace "src/MacVim/icons/Makefile", "$(MAKE) -C makeicns", ""
      inreplace "src/MacVim/icons/make_icons.py", "dont_create = False", "dont_create = True"
    end

    system "make"

    prefix.install "src/MacVim/build/Release/MacVim.app"
    inreplace "src/MacVim/mvim", /^# VIM_APP_DIR=\/Applications$/,
                                 "VIM_APP_DIR=#{prefix}"
    bin.install "src/MacVim/mvim"

    # Create MacVim vimdiff, view, ex equivalents
    executables = %w[mvimdiff mview mvimex gvim gvimdiff gview gvimex]
    executables += %w[vi vim vimdiff view vimex] if build.include? "override-system-vim"
    executables.each {|f| ln_s bin+'mvim', bin+f}
  end

  def caveats
    s = ''
    s += <<-EOS.undent
      MacVim.app installed to:
        #{prefix}

      Run the following to make MacVim available as a Mac OS X application:
          brew linkapps
      or:
          brew linkapps --local
    EOS
    if build.with? "python" and build.with? "python3"
      s += <<-EOS.undent

        MacVim has been built with dynamic loading of Python 2 and Python 3.

        Note: if MacVim dynamically loads both Python 2 and Python 3, it may
        crash. For more information, see:
            http://vimdoc.sourceforge.net/htmldoc/if_pyth.html#python3
      EOS
    end
    return s
  end
end