class Guile < Formula
  desc "GNU Ubiquitous Intelligent Language for Extensions"
  homepage "https://www.gnu.org/software/guile/"
  url "https://ftp.gnu.org/gnu/guile/guile-2.2.6.tar.xz"
  mirror "https://ftpmirror.gnu.org/guile/guile-2.2.6.tar.xz"
  sha256 "b33576331465a60b003573541bf3b1c205936a16c407bc69f8419a527bf5c988"

  bottle do
    sha256 "17506d92107d7209955da7c2adf9ab324d41b9667557a9b1fa81d6f6813149f3" => :mojave
    sha256 "093fc2760544ffff7c69ec0e0767b586e206ca67cf909b51211f7eea368ef9ea" => :high_sierra
    sha256 "32e167bfe1de00fdd3c64e5785edbf5d90b3c8621e3699fd287cb6b09a377d7f" => :sierra
  end

  head do
    url "https://git.savannah.gnu.org/git/guile.git"

    depends_on "autoconf" => :build
    depends_on "automake" => :build
    depends_on "gettext" => :build
  end

  depends_on "gnu-sed" => :build
  depends_on "bdw-gc"
  depends_on "gmp"
  depends_on "libffi"
  depends_on "libtool"
  depends_on "libunistring"
  depends_on "pkg-config" # guile-config is a wrapper around pkg-config.
  depends_on "readline"

  def install
    system "./autogen.sh" unless build.stable?
    system "./configure", "--disable-dependency-tracking",
                          "--prefix=#{prefix}",
                          "--with-libreadline-prefix=#{Formula["readline"].opt_prefix}",
                          "--with-libgmp-prefix=#{Formula["gmp"].opt_prefix}"
    system "make", "install"

    # A really messed up workaround required on macOS --mkhl
    Pathname.glob("#{lib}/*.dylib") do |dylib|
      lib.install_symlink dylib.basename => "#{dylib.basename(".dylib")}.so"
    end

    # This is either a solid argument for guile including options for
    # --with-xyz-prefix= for libffi and bdw-gc or a solid argument for
    # Homebrew automatically removing Cellar paths from .pc files in favour
    # of opt_prefix usage everywhere.
    inreplace lib/"pkgconfig/guile-2.2.pc" do |s|
      s.gsub! Formula["bdw-gc"].prefix.realpath, Formula["bdw-gc"].opt_prefix
      s.gsub! Formula["libffi"].prefix.realpath, Formula["libffi"].opt_prefix
    end

    (share/"gdb/auto-load").install Dir["#{lib}/*-gdb.scm"]
  end

  test do
    hello = testpath/"hello.scm"
    hello.write <<~EOS
      (display "Hello World")
      (newline)
    EOS

    ENV["GUILE_AUTO_COMPILE"] = "0"

    system bin/"guile", hello
  end
end