require 'formula'

class TexInstalled < Requirement
  def message; <<-EOS.undent
    A TeX/LaTeX installation is required to install.
    You can obtain the TeX distribution for Mac OS X from:
        http://www.tug.org/mactex/
    After you install it, put its bin in your PATH and open a new Terminal tab.
    You should also do this because MacTex installs with root ownership:
        sudo chown -R $USER `brew --prefix`
    That will change all the files and directories back to being owned by you.
    EOS
  end
  def satisfied?
    which 'mpost'
  end
  def fatal?
    true
  end
end

class Lilypond < Formula
  homepage 'http://lilypond.org/'
  url 'http://download.linuxaudio.org/lilypond/sources/v2.16/lilypond-2.16.1.tar.gz'
  sha1 'ce923f27091ec5501df7bcd0596f1ffd7ab9b8b9'

  env :userpaths

  option 'with-doc', "Build documentation in addition to binaries (may require several hours)."

  depends_on TexInstalled.new
  depends_on 'pkg-config' => :build
  depends_on 'gettext'
  depends_on 'pango'
  depends_on 'guile'
  depends_on 'ghostscript'
  depends_on 'mftrace'
  depends_on 'fontforge'
  depends_on 'texinfo'
  depends_on :x11

  # Assert documentation dependencies if requested.
  if build.include? 'with-doc'
    depends_on 'netpbm'
    depends_on 'imagemagick'
    depends_on 'docbook'
    depends_on LanguageModuleDependency.new :python, 'dblatex', 'dbtexmf.dblatex'
    depends_on 'texi2html'
  end

  skip_clean :all

  fails_with :clang do
    build 421
    cause 'Strict C99 compliance error in a pointer conversion.'
  end

  def install
    gs = Formula.factory('ghostscript')
    system "./configure", "--prefix=#{prefix}", "--enable-rpath",
                          "--with-ncsb-dir=#{gs.share}/ghostscript/fonts/"

    # Separate steps to ensure that lilypond's custom fonts are created.
    system 'make all'
    system "make install"

    # Build documentation if requested.
    if build.include? 'with-doc'
      system "make doc"
      system "make install-doc"
    end
  end

  def test
    mktemp do
      (Pathname.pwd+'test.ly').write <<-EOS.undent
        \\version "2.16.0"
        \\header { title = "Do-Re-Mi" }
        { c' d' e' }
      EOS
      lilykeg = Formula.factory('lilypond').linked_keg
      system "#{lilykeg}/bin/lilypond test.ly"
    end
  end
end