class Git < Formula
  desc "Distributed revision control system"
  homepage "https://git-scm.com"
  url "https://www.kernel.org/pub/software/scm/git/git-2.12.0.tar.xz"
  sha256 "1821766479062d052cc1897d0ded95212e81e5c7f1039786bc4aec2225a32027"
  head "https://github.com/git/git.git", :shallow => false

  bottle do
    sha256 "db6876e519c871fdfb0f4b2412810eae081a84f6489015791540ed2fd1f77ef7" => :sierra
    sha256 "b9e1276047be119df704f196affd69b69a31348e052f960b9f59b16e22d085fc" => :el_capitan
    sha256 "ac19aaa880323214874a9be2eb98b25d07eafcdecf9e04e0c97df5ddfca9b892" => :yosemite
  end

  option "with-blk-sha1", "Compile with the block-optimized SHA1 implementation"
  option "without-completions", "Disable bash/zsh completions from 'contrib' directory"
  option "with-brewed-openssl", "Build with Homebrew OpenSSL instead of the system version"
  option "with-brewed-curl", "Use Homebrew's version of cURL library"
  option "with-brewed-svn", "Use Homebrew's version of SVN"
  option "with-persistent-https", "Build git-remote-persistent-https from 'contrib' directory"

  depends_on "pcre" => :optional
  depends_on "gettext" => :optional
  depends_on "openssl" if build.with? "brewed-openssl"
  depends_on "curl" if build.with? "brewed-curl"
  depends_on "go" => :build if build.with? "persistent-https"
  # Trigger an install of swig before subversion, as the "swig" doesn't get pulled in otherwise
  # See https://github.com/Homebrew/homebrew/issues/34554
  if build.with? "brewed-svn"
    depends_on "swig"
    depends_on "subversion" => "with-perl"
  end

  resource "html" do
    url "https://www.kernel.org/pub/software/scm/git/git-htmldocs-2.12.0.tar.xz"
    sha256 "bd548faa2c9e63403e528ce4f4e87561e78949a0349a9e2a27e0d6e581d3a8bd"
  end

  resource "man" do
    url "https://www.kernel.org/pub/software/scm/git/git-manpages-2.12.0.tar.xz"
    sha256 "8b8356f8d50eff6499c5d05e87c106a7b1b48bd16de1742fa022631909804773"
  end

  def install
    # If these things are installed, tell Git build system not to use them
    ENV["NO_FINK"] = "1"
    ENV["NO_DARWIN_PORTS"] = "1"
    ENV["V"] = "1" # build verbosely
    ENV["NO_R_TO_GCC_LINKER"] = "1" # pass arguments to LD correctly
    ENV["PYTHON_PATH"] = which "python"
    ENV["PERL_PATH"] = which "perl"

    perl_version = /\d\.\d+/.match(`perl --version`)

    if build.with? "brewed-svn"
      ENV["PERLLIB_EXTRA"] = %W[
        #{Formula["subversion"].opt_lib}/perl5/site_perl
        #{Formula["subversion"].opt_prefix}/Library/Perl/#{perl_version}/darwin-thread-multi-2level
      ].join(":")
    elsif MacOS.version >= :mavericks
      ENV["PERLLIB_EXTRA"] = %W[
        #{MacOS.active_developer_dir}
        /Library/Developer/CommandLineTools
        /Applications/Xcode.app/Contents/Developer
      ].uniq.map do |p|
        "#{p}/Library/Perl/#{perl_version}/darwin-thread-multi-2level"
      end.join(":")
    end

    unless quiet_system ENV["PERL_PATH"], "-e", "use ExtUtils::MakeMaker"
      ENV["NO_PERL_MAKEMAKER"] = "1"
    end

    ENV["BLK_SHA1"] = "1" if build.with? "blk-sha1"

    if build.with? "pcre"
      ENV["USE_LIBPCRE"] = "1"
      ENV["LIBPCREDIR"] = Formula["pcre"].opt_prefix
    end

    ENV["NO_GETTEXT"] = "1" if build.without? "gettext"

    args = %W[
      prefix=#{prefix}
      sysconfdir=#{etc}
      CC=#{ENV.cc}
      CFLAGS=#{ENV.cflags}
      LDFLAGS=#{ENV.ldflags}
    ]
    args << "NO_OPENSSL=1" << "APPLE_COMMON_CRYPTO=1" if build.without? "brewed-openssl"

    system "make", "install", *args

    # Install the macOS keychain credential helper
    cd "contrib/credential/osxkeychain" do
      system "make", "CC=#{ENV.cc}",
                     "CFLAGS=#{ENV.cflags}",
                     "LDFLAGS=#{ENV.ldflags}"
      bin.install "git-credential-osxkeychain"
      system "make", "clean"
    end

    # Install the netrc credential helper
    cd "contrib/credential/netrc" do
      system "make", "test"
      bin.install "git-credential-netrc"
    end

    # Install git-subtree
    cd "contrib/subtree" do
      system "make", "CC=#{ENV.cc}",
                     "CFLAGS=#{ENV.cflags}",
                     "LDFLAGS=#{ENV.ldflags}"
      bin.install "git-subtree"
    end

    if build.with? "persistent-https"
      cd "contrib/persistent-https" do
        system "make"
        bin.install "git-remote-persistent-http",
                    "git-remote-persistent-https",
                    "git-remote-persistent-https--proxy"
      end
    end

    if build.with? "completions"
      # install the completion script first because it is inside "contrib"
      bash_completion.install "contrib/completion/git-completion.bash"
      bash_completion.install "contrib/completion/git-prompt.sh"

      zsh_completion.install "contrib/completion/git-completion.zsh" => "_git"
      cp "#{bash_completion}/git-completion.bash", zsh_completion
    end

    elisp.install Dir["contrib/emacs/*.el"]
    (share/"git-core").install "contrib"

    # We could build the manpages ourselves, but the build process depends
    # on many other packages, and is somewhat crazy, this way is easier.
    man.install resource("man")
    (share/"doc/git-doc").install resource("html")

    # Make html docs world-readable
    chmod 0644, Dir["#{share}/doc/git-doc/**/*.{html,txt}"]
    chmod 0755, Dir["#{share}/doc/git-doc/{RelNotes,howto,technical}"]

    # To avoid this feature hooking into the system OpenSSL, remove it.
    # If you need it, install git --with-brewed-openssl.
    rm "#{libexec}/git-core/git-imap-send" if build.without? "brewed-openssl"

    # Set the macOS keychain credential helper by default
    # (as Apple's CLT's git also does this).
    (buildpath/"gitconfig").write <<-EOS.undent
      [credential]
      \thelper = osxkeychain
    EOS
    etc.install "gitconfig"
  end

  test do
    system bin/"git", "init"
    %w[haunted house].each { |f| touch testpath/f }
    system bin/"git", "add", "haunted", "house"
    system bin/"git", "commit", "-a", "-m", "Initial Commit"
    assert_equal "haunted\nhouse", shell_output("#{bin}/git ls-files").strip
  end
end