class BoostAT157 < Formula
  desc "Collection of portable C++ source libraries"
  homepage "https://www.boost.org"
  url "https://downloads.sourceforge.net/project/boost/boost/1.57.0/boost_1_57_0.tar.bz2"
  sha256 "910c8c022a33ccec7f088bd65d4f14b466588dda94ba2124e78b8c57db264967"

  bottle do
    cellar :any
    sha256 "a9eab1fbd081d88a4ee1d8102a038784b46ef98d77f11943793f8445341871ae" => :high_sierra
    sha256 "2a5722e316d528b2ee1b290c2bda772c19c426f32c8bcb6609c250d68c59d6cb" => :sierra
    sha256 "1c2b58d63f0d0f24a07cb60653cf1e674b78f4529c5e7b89ea4208d4db8fb494" => :el_capitan
    sha256 "993b2b875755b7a1b0b7bbb97269545705fa3b30df3e4a03868c0e53a1dc7599" => :yosemite
  end

  keg_only :versioned_formula

  option "with-icu4c", "Build regexp engine with icu support"
  option "without-single", "Disable building single-threading variant"
  option "without-static", "Disable building static library variant"
  option :cxx11

  if build.cxx11?
    depends_on "icu4c" => [:optional, "c++11"]
  else
    depends_on "icu4c" => :optional
  end

  needs :cxx11 if build.cxx11?

  def install
    # Force boost to compile with the desired compiler
    open("user-config.jam", "a") do |file|
      file.write "using darwin : : #{ENV.cxx} ;\n"
    end

    # libdir should be set by --prefix but isn't
    bootstrap_args = ["--prefix=#{prefix}", "--libdir=#{lib}"]

    if build.with? "icu4c"
      icu4c_prefix = Formula["icu4c"].opt_prefix
      bootstrap_args << "--with-icu=#{icu4c_prefix}"
    else
      bootstrap_args << "--without-icu"
    end

    # Handle libraries that will not be built.
    without_libraries = ["python", "mpi"]

    # Boost.Log cannot be built using Apple GCC at the moment. Disabled
    # on such systems.
    without_libraries << "log" if ENV.compiler == :gcc

    bootstrap_args << "--without-libraries=#{without_libraries.join(",")}"

    # layout should be synchronized with boost-python
    args = ["--prefix=#{prefix}",
            "--libdir=#{lib}",
            "-d2",
            "-j#{ENV.make_jobs}",
            "--layout=tagged",
            "--user-config=user-config.jam",
            "install"]

    if build.with? "single"
      args << "threading=multi,single"
    else
      args << "threading=multi"
    end

    if build.with? "static"
      args << "link=shared,static"
    else
      args << "link=shared"
    end

    # Trunk starts using "clang++ -x c" to select C compiler which breaks C++11
    # handling using ENV.cxx11. Using "cxxflags" and "linkflags" still works.
    if build.cxx11?
      args << "cxxflags=-std=c++11"
      if ENV.compiler == :clang
        args << "cxxflags=-stdlib=libc++" << "linkflags=-stdlib=libc++"
      end
    end

    system "./bootstrap.sh", *bootstrap_args
    system "./b2", "headers"
    system "./b2", *args
  end

  def caveats
    s = ""
    # ENV.compiler doesn't exist in caveats. Check library availability
    # instead.
    if Dir["#{lib}/libboost_log*"].empty?
      s += <<~EOS
        Building of Boost.Log is disabled because it requires newer GCC or Clang.
      EOS
    end

    s
  end

  test do
    (testpath/"test.cpp").write <<~EOS
      #include <boost/algorithm/string.hpp>
      #include <string>
      #include <vector>
      #include <assert.h>
      using namespace boost::algorithm;
      using namespace std;

      int main()
      {
        string str("a,b");
        vector<string> strVec;
        split(strVec, str, is_any_of(","));
        assert(strVec.size()==2);
        assert(strVec[0]=="a");
        assert(strVec[1]=="b");
        return 0;
      }
    EOS
    system ENV.cxx, "test.cpp", "-std=c++1y", "-I#{include}", "-L#{lib}",
                                "-lboost_system", "-o", "test"
    system "./test"
  end
end