# # @param task [FFI::Compiler::CompileTask] task to configure def configure_common_compile_task(task)

if FileUtils.pwd.include? 'ext'
  src_dir = '.'
  third_party_path = 'third_party/utf8_range'
else
  src_dir = 'ext/google/protobuf_c'
  third_party_path = 'ext/google/protobuf_c/third_party/utf8_range'
end

task.add_include_path third_party_path
task.add_define 'NDEBUG'
task.cflags << "-std=gnu99 -O3"
[
  :convert, :defs, :map, :message, :protobuf, :repeated_field, :wrap_memcpy
].each { |file| task.exclude << "/#{file}.c" }
task.ext_dir = src_dir
task.source_dirs = [src_dir]
if RbConfig::CONFIG['target_os'] =~ /darwin|linux/
  task.cflags << "-Wall -Wsign-compare -Wno-declaration-after-statement"
end

end

# FFI::CompilerTask’s constructor walks the filesystem at task definition time # to create subtasks for each source file, so files from third_party must be # copied into place before the task is defined for it to work correctly. # TODO Is there a sane way to check for generated protos under lib too? def with_generated_files

expected_path = FileUtils.pwd.include?('ext') ? 'third_party/utf8_range' : 'ext/google/protobuf_c/third_party/utf8_range'
if File.directory?(expected_path)
  yield
else
  task :default do
    # It is possible, especially in cases like the first invocation of
    # `rake test` following `rake clean` or a fresh checkout that the
    # `copy_third_party` task has been executed since initial task definition.
    # If so, run the task definition block now and invoke it explicitly.
    if File.directory?(expected_path)
      yield
      Rake::Task[:default].invoke
    else
      raise "Missing directory #{File.absolute_path(expected_path)}." +
              " Did you forget to run `rake copy_third_party` before building" +
              " native extensions?"
    end
  end
end

end

begin

require "ffi-compiler/compile_task"

desc "Compile Protobuf library for FFI"
namespace "ffi-protobuf" do
  with_generated_files do
    # Compile Ruby UPB separately in order to limit use of -DUPB_BUILD_API to one
    # compilation unit.
    desc "Compile UPB library for FFI"
    namespace "ffi-upb" do
      with_generated_files do
        FFI::Compiler::CompileTask.new('ruby-upb') do |c|
          configure_common_compile_task c
          c.add_define "UPB_BUILD_API"
          c.exclude << "/glue.c"
          c.exclude << "/shared_message.c"
          c.exclude << "/shared_convert.c"
          if RbConfig::CONFIG['target_os'] =~ /darwin|linux/
            c.cflags << "-fvisibility=hidden"
          end
        end
      end
    end

    FFI::Compiler::CompileTask.new 'protobuf_c_ffi' do |c|
      configure_common_compile_task c
      # Ruby UPB was already compiled with different flags.
      c.exclude << "/utf8_range.c"
      c.exclude << "/ruby-upb.c"
    end

    # Setup dependencies so that the .o files generated by building ffi-upb are
    # available to link here.
    # TODO Can this be simplified? Can the single shared library be used
    # instead of the object files?
    protobuf_c_task = Rake::Task[:default]
    protobuf_c_shared_lib_task = Rake::Task[protobuf_c_task.prereqs.last]
    ruby_upb_shared_lib_task = Rake::Task[:"ffi-upb:default"].prereqs.first
    Rake::Task[ruby_upb_shared_lib_task].prereqs.each do |dependency|
      protobuf_c_shared_lib_task.prereqs.prepend dependency
    end
  end
end

rescue LoadError

desc "Compile Protobuf library for FFI"
namespace "ffi-protobuf" do
  task :default do
    warn "Skipping build of FFI; `gem install ffi-compiler` to enable."
  end
end

end