MRuby.each_target do

if enable_gems?
  # set up all gems
  gems.each(&:setup)
  gems.check self

  # loader all gems
  self.libmruby_objs << objfile("#{build_dir}/mrbgems/gem_init")
  file objfile("#{build_dir}/mrbgems/gem_init") => ["#{build_dir}/mrbgems/gem_init.c", "#{build_dir}/LEGAL"]
  file "#{build_dir}/mrbgems/gem_init.c" => [MRUBY_CONFIG, __FILE__] do |t|
    FileUtils.mkdir_p "#{build_dir}/mrbgems"
    open(t.name, 'w') do |f|
      gem_func_gems = gems.select { |g| g.generate_functions }
      gem_func_decls = gem_func_gems.each_with_object('') do |g, s|
        s << "void GENERATED_TMP_mrb_#{g.funcname}_gem_init(mrb_state*);\n" \
             "void GENERATED_TMP_mrb_#{g.funcname}_gem_final(mrb_state*);\n"
      end
      gem_init_calls = gem_func_gems.each_with_object('') do |g, s|
        s << "  GENERATED_TMP_mrb_#{g.funcname}_gem_init(mrb);\n"
      end
      gem_final_calls = gem_func_gems.reverse_each.with_object('') do |g, s|
        s << "  GENERATED_TMP_mrb_#{g.funcname}_gem_final(mrb);\n"
      end
      f.puts %Q[  ]
      f.puts %Q[ * This file contains a list of all]
      f.puts %Q[ * initializing methods which are]
      f.puts %Q[ * necessary to bootstrap all gems.]
      f.puts %Q[ *]
      f.puts %Q[ * IMPORTANT:]
      f.puts %Q[ *   This file was generated!]
      f.puts %Q[ *   All manual changes will get lost.]
      f.puts %Q[   ]
      f.puts %Q[]
      f.puts %Q[#include <mruby.h>]
      f.puts %Q[]
      f.write gem_func_decls
      unless gem_final_calls.empty?
      f.puts %Q[]
        f.puts %Q[static void]
        f.puts %Q[mrb_final_mrbgems(mrb_state *mrb) {]
        f.write gem_final_calls
        f.puts %Q[}]
      end
      f.puts %Q[]
      f.puts %Q[void]
      f.puts %Q[mrb_init_mrbgems(mrb_state *mrb) {]
      f.write gem_init_calls
      f.puts %Q[  mrb_state_atexit(mrb, mrb_final_mrbgems);] unless gem_final_calls.empty?
      f.puts %Q[}]
    end
  end
end

# legal documents
file "#{build_dir}/LEGAL" => [MRUBY_CONFIG, __FILE__] do |t|
  FileUtils.mkdir_p File.dirname t.name
  open(t.name, 'w+') do |f|
   f.puts <<LEGAL

Copyright © #{Time.now.year} mruby developers

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. LEGAL

if enable_gems?
  f.puts <<GEMS_LEGAL

Additional Licenses

Due to the reason that you choosed additional mruby packages (GEMS), please check the following additional licenses too: GEMS_LEGAL

      gems.map do |g|
        authors = [g.authors].flatten.sort.join(", ")
        f.puts
        f.puts "GEM: #{g.name}"
        f.puts "Copyright (c) #{Time.now.year} #{authors}"
        f.puts "License: #{g.licenses}"
      end
    end
  end
end

end