# Copyright (c) 2012, HipByte SPRL and contributors
# All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
# 
# 1. Redistributions of source code must retain the above copyright notice, this
#    list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

require 'thread'

module Motion; module Project;
  class Builder
    include Rake::DSL if Object.const_defined?(:Rake) && Rake.const_defined?(:DSL)

    def build(config, platform, opts)
      datadir = config.datadir
      archs = config.archs[platform]

      static_library = opts.delete(:static)

      ruby = File.join(config.bindir, 'ruby')
      llc = File.join(config.bindir, 'llc')
      @nfd = File.join(config.bindir, 'nfd')

      if config.spec_mode and (config.spec_files - config.spec_core_files).empty?
        App.fail "No spec files in `#{config.specs_dir}'"
      end

      config.resources_dirs.flatten!

      # Locate SDK and compilers.
      sdk = config.sdk(platform)
      cc = config.locate_compiler(platform, 'clang')
      cxx = config.locate_compiler(platform, 'clang++')
    
      build_dir = File.join(config.versionized_build_dir(platform))
      App.info 'Build', build_dir
 
      # Prepare the list of BridgeSupport files needed. 
      bs_files = config.bridgesupport_files

      # Build vendor libraries.
      vendor_libs = []
      config.vendor_projects.each do |vendor_project|
        vendor_project.build(platform)
        vendor_libs.concat(vendor_project.libs)
        bs_files.concat(vendor_project.bs_files)
      end

      # Validate common build directory.
      if !File.directory?(Builder.common_build_dir) or !File.writable?(Builder.common_build_dir)
        $stderr.puts "Cannot write into the `#{Builder.common_build_dir}' directory, please remove or check permissions and try again."
        exit 1
      end

      # Prepare embedded frameworks BridgeSupport files (OSX-only).
      embedded_frameworks = (config.respond_to?(:embedded_frameworks) ? config.embedded_frameworks.map { |x| File.expand_path(x) } : [])
      unless embedded_frameworks.empty?
        embedded_frameworks.each do |path|
          headers = Dir.glob(File.join(path, 'Headers/**/*.h'))
          bs_file = File.join(Builder.common_build_dir, File.expand_path(path) + '.bridgesupport')
          if !File.exist?(bs_file) or File.mtime(path) > File.mtime(bs_file)
            FileUtils.mkdir_p(File.dirname(bs_file))
            config.gen_bridge_metadata(platform, headers, bs_file, '', [])
          end
          bs_files << bs_file
        end
      end

      # Build object files.
      objs_build_dir = File.join(build_dir, 'objs')
      FileUtils.mkdir_p(objs_build_dir)
      any_obj_file_built = false
      project_files = Dir.glob("**/*.rb").map{ |x| File.expand_path(x) }
      is_default_archs = (archs == config.default_archs[platform])
      rubyc_bs_flags = bs_files.map { |x| "--uses-bs \"" + x + "\" " }.join(' ')

      build_file = Proc.new do |files_build_dir, path|
        rpath = path
        path = File.expand_path(path)
        if is_default_archs && !project_files.include?(path)
          files_build_dir = File.expand_path(File.join(Builder.common_build_dir, files_build_dir))
        end
        obj = File.join(files_build_dir, "#{path}.o")
        should_rebuild = (!File.exist?(obj) \
            or File.mtime(path) > File.mtime(obj) \
            or File.mtime(ruby) > File.mtime(obj))
 
        # Generate or retrieve init function.
        init_func = should_rebuild ? "MREP_#{`/usr/bin/uuidgen`.strip.gsub('-', '')}" : `#{config.locate_binary('nm')} \"#{obj}\"`.scan(/T\s+_(MREP_.*)/)[0][0]

        if should_rebuild
          App.info 'Compile', rpath
          FileUtils.mkdir_p(File.dirname(obj))
          arch_objs = []
          archs.each do |arch|
            # Locate arch kernel.
            kernel = File.join(datadir, platform, "kernel-#{arch}.bc")
            raise "Can't locate kernel file" unless File.exist?(kernel)
   
            # Assembly.
            asm = File.join(files_build_dir, "#{path}.#{arch}.s")
            arm64 = false
            compiler_exec_arch = case arch
              when /^arm/
                (arm64 = (arch == 'arm64')) ? 'x86_64' : 'i386'
              else
                arch
            end
            sh "/usr/bin/env VM_KERNEL_PATH=\"#{kernel}\" VM_OPT_LEVEL=\"#{config.opt_level}\" /usr/bin/arch -arch #{compiler_exec_arch} #{ruby} #{rubyc_bs_flags} --emit-llvm \"#{asm}\" #{init_func} \"#{path}\""

            # Object 
            arch_obj = File.join(files_build_dir, "#{path}.#{arch}.o")
            if arm64
              # At the time of this writing Apple hasn't yet contributed the source code of the LLVM backend for the "arm64" architecture, so the RubyMotion compiler can't emit proper assembly yet. We work around this limitation by generating bitcode instead and giving it to the linker. Ugly but should be temporary (right?).
              @dummy_object_file ||= begin
                src_path = '/tmp/__dummy_object_file__.c'
                obj_path = '/tmp/__dummy_object_file__.o'
                File.open(src_path, 'w') { |io| io.puts "static int foo(void) { return 42; }" }
                sh "#{cc} -c #{src_path} -o #{obj_path} -arch arm64 -miphoneos-version-min=7.0"
                obj_path
              end
              sh "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld \"#{asm}\" \"#{@dummy_object_file}\" -arch arm64 -r -o \"#{arch_obj}\"" 
            else
              sh "#{cc} -fexceptions -c -arch #{arch} \"#{asm}\" -o \"#{arch_obj}\""
            end

            [asm].each { |x| File.unlink(x) } unless ENV['keep_temps']
            arch_objs << arch_obj
          end
   
          # Assemble fat binary.
          arch_objs_list = arch_objs.map { |x| "\"#{x}\"" }.join(' ')
          sh "/usr/bin/lipo -create #{arch_objs_list} -output \"#{obj}\""
        end

        any_obj_file_built = true
        [obj, init_func]
      end

      # Resolve file dependencies.
      if config.detect_dependencies == true
        config.dependencies = Dependency.new(config.files - config.exclude_from_detect_dependencies, config.dependencies).run
      end

      parallel = ParallelBuilder.new(objs_build_dir, build_file)
      parallel.files = config.ordered_build_files
      parallel.run
      objs = parallel.objects

      FileUtils.touch(objs_build_dir) if any_obj_file_built

      app_objs = objs
      spec_objs = []
      if config.spec_mode
        # Build spec files too, but sequentially.
        parallel = ParallelBuilder.new(objs_build_dir, build_file)
        parallel.files = config.spec_files
        parallel.run
        spec_objs = parallel.objects
        objs += spec_objs
      end

      # Generate init file.
      init_txt = <<EOS
extern "C" {
    void ruby_sysinit(int *, char ***);
    void ruby_init(void);
    void ruby_init_loadpath(void);
    void ruby_script(const char *);
    void ruby_set_argv(int, char **);
    void rb_vm_init_compiler(void);
    void rb_vm_init_jit(void);
    void rb_vm_aot_feature_provide(const char *, void *);
    void *rb_vm_top_self(void);
    void rb_define_global_const(const char *, void *);
    void rb_rb2oc_exc_handler(void);
    void rb_exit(int);
EOS
      app_objs.each do |_, init_func|
        init_txt << "void #{init_func}(void *, void *);\n"
      end
      init_txt << <<EOS
}

extern "C"
void
RubyMotionInit(int argc, char **argv)
{
    static bool initialized = false;
    if (!initialized) {
	ruby_init();
	ruby_init_loadpath();
        if (argc > 0) {
	    const char *progname = argv[0];
	    ruby_script(progname);
	}
#if !__LP64__
	try {
#endif
	    void *self = rb_vm_top_self();
EOS
      init_txt << config.define_global_env_txt
      app_objs.each do |_, init_func|
        init_txt << "#{init_func}(self, 0);\n"
      end
      init_txt << <<EOS
#if !__LP64__
	}
	catch (...) {
	    rb_rb2oc_exc_handler();
	}
#endif
	initialized = true;
    }
}
EOS

      # Compile init file.
      init = File.join(objs_build_dir, 'init.mm')
      init_o = File.join(objs_build_dir, 'init.o')
      if !(File.exist?(init) and File.exist?(init_o) and File.read(init) == init_txt)
        File.open(init, 'w') { |io| io.write(init_txt) }
        sh "#{cxx} \"#{init}\" #{config.cflags(platform, true)} -c -o \"#{init_o}\""
      end

      if static_library
        # Create a static archive with all object files + the runtime.
        lib = File.join(config.versionized_build_dir(platform), config.name + '.a')
        App.info 'Create', lib
        libmacruby = File.join(datadir, platform, 'libmacruby-static.a')
        objs_list = objs.map { |path, _| path }.unshift(init_o, *config.frameworks_stubs_objects(platform)).map { |x| "\"#{x}\"" }.join(' ')
        sh "/usr/bin/libtool -static \"#{libmacruby}\" #{objs_list} -o \"#{lib}\""
        return lib
      end

      # Generate main file.
      main_txt = config.main_cpp_file_txt(spec_objs)
 
      # Compile main file.
      main = File.join(objs_build_dir, 'main.mm')
      main_o = File.join(objs_build_dir, 'main.o')
      if !(File.exist?(main) and File.exist?(main_o) and File.read(main) == main_txt)
        File.open(main, 'w') { |io| io.write(main_txt) }
        sh "#{cxx} \"#{main}\" #{config.cflags(platform, true)} -c -o \"#{main_o}\""
      end

      # Prepare bundle.
      bundle_path = config.app_bundle(platform)
      unless File.exist?(bundle_path)
        App.info 'Create', bundle_path
        FileUtils.mkdir_p(bundle_path)
      end

      # Link executable.
      main_exec = config.app_bundle_executable(platform)
      unless File.exist?(File.dirname(main_exec))
        App.info 'Create', File.dirname(main_exec)
        FileUtils.mkdir_p(File.dirname(main_exec))
      end
      main_exec_created = false
      if !File.exist?(main_exec) \
          or File.mtime(config.project_file) > File.mtime(main_exec) \
          or objs.any? { |path, _| File.mtime(path) > File.mtime(main_exec) } \
	  or File.mtime(main_o) > File.mtime(main_exec) \
          or vendor_libs.any? { |lib| File.mtime(lib) > File.mtime(main_exec) } \
          or File.mtime(File.join(datadir, platform, 'libmacruby-static.a')) > File.mtime(main_exec)
        App.info 'Link', main_exec
        objs_list = objs.map { |path, _| path }.unshift(init_o, main_o, *config.frameworks_stubs_objects(platform)).map { |x| "\"#{x}\"" }.join(' ')
        framework_search_paths = (config.framework_search_paths + embedded_frameworks.map { |x| File.dirname(x) }).uniq.map { |x| "-F#{File.expand_path(x)}" }.join(' ')
        frameworks = (config.frameworks_dependencies + embedded_frameworks.map { |x| File.basename(x, '.framework') }).map { |x| "-framework #{x}" }.join(' ')
        weak_frameworks = config.weak_frameworks.map { |x| "-weak_framework #{x}" }.join(' ')
        vendor_libs = config.vendor_projects.inject([]) do |libs, vendor_project|
          libs << vendor_project.libs.map { |x|
            (vendor_project.opts[:force_load] ? '-force_load ' : '-ObjC ') + "\"#{x}\""
          }
        end.join(' ')
        linker_option = begin
          m = config.deployment_target.match(/(\d+)/)
          if m[0].to_i < 7
            "-stdlib=libstdc++"
          end
        end || ""
        sh "#{cxx} -o \"#{main_exec}\" #{objs_list} #{config.ldflags(platform)} -L#{File.join(datadir, platform)} -lmacruby-static -lobjc -licucore #{linker_option} #{framework_search_paths} #{frameworks} #{weak_frameworks} #{config.libs.join(' ')} #{vendor_libs}"
        main_exec_created = true

        # Change the install name of embedded frameworks.
        embedded_frameworks.each do |path|
          res = `/usr/bin/otool -L \"#{main_exec}\"`.scan(/(.*#{File.basename(path)}.*)\s\(/)
          if res and res[0] and res[0][0]
            old_path = res[0][0].strip
            new_path = "@executable_path/../Frameworks/" + old_path.scan(/#{File.basename(path)}.*/)[0]
            sh "/usr/bin/install_name_tool -change \"#{old_path}\" \"#{new_path}\" \"#{main_exec}\""
          else
            App.warn "Cannot locate and fix install name path of embedded framework `#{path}' in executable `#{main_exec}', application might not start"
          end
        end
      end

      # Create bundle/PkgInfo.
      bundle_pkginfo = File.join(bundle_path, 'PkgInfo')
      if !File.exist?(bundle_pkginfo) or File.mtime(config.project_file) > File.mtime(bundle_pkginfo)
        App.info 'Create', bundle_pkginfo
        File.open(bundle_pkginfo, 'w') { |io| io.write(config.pkginfo_data) }
      end

      # Compile IB resources.
      config.resources_dirs.each do |dir|
        if File.exist?(dir)
          ib_resources = []
          ib_resources.concat((Dir.glob(File.join(dir, '**', '*.xib')) + Dir.glob(File.join(dir, '*.lproj', '*.xib'))).map { |xib| [xib, xib.sub(/\.xib$/, '.nib')] })
          ib_resources.concat(Dir.glob(File.join(dir, '**', '*.storyboard')).map { |storyboard| [storyboard, storyboard.sub(/\.storyboard$/, '.storyboardc')] })
          ib_resources.each do |src, dest|
            if !File.exist?(dest) or File.mtime(src) > File.mtime(dest)
              App.info 'Compile', src
              sh "/usr/bin/ibtool --compile \"#{dest}\" \"#{src}\""
            end
          end
        end
      end

      preserve_resources = []

      # Compile Asset Catalog bundles.
      assets_bundles = config.assets_bundles
      unless assets_bundles.empty?
        app_icons_asset_bundle = config.app_icons_asset_bundle
        if app_icons_asset_bundle
          app_icons_info_plist_path = config.app_icons_info_plist_path(platform)
          app_icons_options = "--output-partial-info-plist \"#{app_icons_info_plist_path}\" " \
                              "--app-icon \"#{config.app_icon_name_from_asset_bundle}\""
        end

        App.info 'Compile', assets_bundles.join(", ")
        app_resources_dir = File.expand_path(config.app_resources_dir(platform))
        FileUtils.mkdir_p(app_resources_dir)
        cmd = "\"#{config.xcode_dir}/usr/bin/actool\" --output-format human-readable-text " \
              "--notices --warnings --platform #{config.deploy_platform.downcase} " \
              "--minimum-deployment-target #{config.deployment_target} " \
              "#{Array(config.device_family).map { |d| "--target-device #{d}" }.join(' ')} " \
              "#{app_icons_options} --compress-pngs --compile \"#{app_resources_dir}\" " \
              "\"#{assets_bundles.map { |f| File.expand_path(f) }.join('" "')}\""
        $stderr.puts(cmd) if App::VERBOSE
        actool_output = `#{cmd} 2>&1`
        $stderr.puts(actool_output) if App::VERBOSE

        # Split output in warnings and compiled files
        actool_output, actool_compilation_results = actool_output.split('/* com.apple.actool.compilation-results */')
        actool_compiled_files = actool_compilation_results.strip.split("\n")
        if actool_document_warnings = actool_output.split('/* com.apple.actool.document.warnings */').last
          # Propagate warnings to the user.
          actool_document_warnings.strip.split("\n").each { |w| App.warn(w) }
        end

        # Remove the partial Info.plist line and preserve all other assets.
        actool_compiled_files.delete(app_icons_info_plist_path) if app_icons_asset_bundle
        preserve_resources.concat(actool_compiled_files.map { |f| File.basename(f) })

        config.configure_app_icons_from_asset_bundle(platform) if app_icons_asset_bundle
      end

      # Compile CoreData Model resources and SpriteKit atlas files.
      config.resources_dirs.each do |dir|
        if File.exist?(dir)
          Dir.glob(File.join(dir, '*.xcdatamodeld')).each do |model|
            momd = model.sub(/\.xcdatamodeld$/, '.momd')
            if !File.exist?(momd) or File.mtime(model) > File.mtime(momd)
              App.info 'Compile', model
              model = File.expand_path(model) # momc wants absolute paths.
              momd = File.expand_path(momd)
              sh "\"#{App.config.xcode_dir}/usr/bin/momc\" \"#{model}\" \"#{momd}\""
            end
          end
          if cmd = config.spritekit_texture_atlas_compiler
            Dir.glob(File.join(dir, '*.atlas')).each do |atlas|
              if File.directory?(atlas)
                App.info 'Compile', atlas
                sh "\"#{cmd}\" \"#{atlas}\" \"#{bundle_path}\""
              end
            end
          end
        end
      end

      # Copy embedded frameworks.
      unless embedded_frameworks.empty?
        app_frameworks = File.join(config.app_bundle(platform), 'Frameworks')
        FileUtils.mkdir_p(app_frameworks)
        embedded_frameworks.each do |src_path|
          dest_path = File.join(app_frameworks, File.basename(src_path))
          if !File.exist?(dest_path) or File.mtime(src_path) > File.mtime(dest_path)
            App.info 'Copy', src_path
            FileUtils.cp_r(src_path, dest_path)
          end 
        end
      end

      # Create bundle/Info.plist.
      bundle_info_plist = File.join(bundle_path, 'Info.plist')
      if !File.exist?(bundle_info_plist) or File.mtime(config.project_file) > File.mtime(bundle_info_plist)
        App.info 'Create', bundle_info_plist
        File.open(bundle_info_plist, 'w') { |io| io.write(config.info_plist_data(platform)) }
        sh "/usr/bin/plutil -convert binary1 \"#{bundle_info_plist}\""
      end

      # Copy resources, handle subdirectories.
      app_resources_dir = config.app_resources_dir(platform)
      FileUtils.mkdir_p(app_resources_dir)
      reserved_app_bundle_files = [
        '_CodeSignature/CodeResources', 'CodeResources', 'embedded.mobileprovision',
        'Info.plist', 'PkgInfo', 'ResourceRules.plist',
        convert_filesystem_encoding(config.name)
      ]
      resources_exclude_extnames = ['.xib', '.storyboard', '.xcdatamodeld', '.atlas', '.xcassets']
      resources_paths = []
      config.resources_dirs.each do |dir|
        if File.exist?(dir)
          resources_paths << Dir.chdir(dir) do
            Dir.glob('**{,/*/**}/*').reject do |x|
              # Find files with extnames to exclude or files inside bundles to
              # exclude (e.g. xcassets).
              File.extname(x) == '.lproj' ||
                resources_exclude_extnames.include?(File.extname(x)) ||
                  resources_exclude_extnames.include?(File.extname(x.split('/').first))
            end.map { |file| File.join(dir, file) }
          end
        end
      end
      resources_paths.flatten!
      resources_paths.each do |res_path|
        res = path_on_resources_dirs(config.resources_dirs, res_path)
        if reserved_app_bundle_files.include?(res)
          App.fail "Cannot use `#{res_path}' as a resource file because it's a reserved application bundle file"
        end
        copy_resource(res_path, File.join(app_resources_dir, res))
      end

      # Delete old resource files.
      resources_files = resources_paths.map { |x| path_on_resources_dirs(config.resources_dirs, x) }
      Dir.chdir(app_resources_dir) do
        Dir.glob('*').each do |bundle_res|
          next if File.directory?(bundle_res)
          next if reserved_app_bundle_files.include?(bundle_res)
          next if resources_files.include?(bundle_res)
          next if preserve_resources.include?(File.basename(bundle_res))
          App.warn "File `#{bundle_res}' found in app bundle but not in resource directories, removing"
          FileUtils.rm_rf(bundle_res)
        end
      end

      # Generate dSYM.
      dsym_path = config.app_bundle_dsym(platform)
      if !File.exist?(dsym_path) or File.mtime(main_exec) > File.mtime(dsym_path)
        App.info "Create", dsym_path
        sh "/usr/bin/dsymutil \"#{main_exec}\" -o \"#{dsym_path}\""
      end

      # Strip all symbols. Only in distribution mode.
      if main_exec_created and config.distribution_mode
        App.info "Strip", main_exec
        sh "#{config.locate_binary('strip')} #{config.strip_args} \"#{main_exec}\""
      end
    end

    def path_on_resources_dirs(dirs, path)
      dir = dirs.each do |dir|
        break dir if path =~ /^#{dir}/
      end
      path = path.sub(/^#{dir}\/*/, '') if dir
      path
    end

    def convert_filesystem_encoding(string)
      eval `#{@nfd} "#{string}"`
    end

    def copy_resource(res_path, dest_path)
      if !File.exist?(dest_path) or File.mtime(res_path) > File.mtime(dest_path)
        FileUtils.mkdir_p(File.dirname(dest_path))
        App.info 'Copy', res_path
        FileUtils.cp_r(res_path, dest_path)
      end
    end

    class << self
      def common_build_dir
        dir = File.expand_path("~/Library/RubyMotion/build")
        unless File.exist?(dir)
          begin
            FileUtils.mkdir_p dir
          rescue
          end
        end
        dir
      end
    end
  end

  class ParallelBuilder
    attr_accessor :files

    def initialize(objs_build_dir, builder)
      @builders_count = begin
        if jobs = ENV['jobs']
          jobs.to_i
        else
          `/usr/sbin/sysctl -n machdep.cpu.thread_count`.strip.to_i
        end
      end
      @builders_count = 1 if @builders_count < 1

      @builders = []
      @builders_count.times do
        queue = []
        th = Thread.new do
          sleep
          objs = []
          while path = queue.shift
            objs << builder.call(objs_build_dir, path)
          end
          queue.concat(objs)
        end
        @builders << [queue, th]
      end
    end

    def run
      builder_i = 0
      @files.each do |path|
        @builders[builder_i][0] << path
        builder_i += 1
        builder_i = 0 if builder_i == @builders_count
      end
 
      # Start build.
      @builders.each do |queue, th|
        sleep 0.01 while th.status != 'sleep'
        th.wakeup
      end
      @builders.each { |queue, th| th.join }
      @builders
    end

    def objects
      objs = []
      builder_i = 0
      @files.each do |path|
        objs << @builders[builder_i][0].shift
        builder_i += 1
        builder_i = 0 if builder_i == @builders_count
      end
      objs
    end
  end

  class Dependency
    begin
      require 'ripper'
    rescue LoadError
      $:.unshift(File.expand_path(File.join(File.dirname(__FILE__), '../../ripper18')))
      require 'ripper'
    end

    @file_paths = []

    def initialize(paths, dependencies)
      @file_paths = paths.flatten.sort
      @dependencies = dependencies
    end

    def cyclic?(dependencies, def_path, ref_path)
      deps = dependencies[def_path]
      if deps
        if deps.include?(ref_path)
          return true
        end
        deps.each do |file|
          return true if cyclic?(dependencies, file, ref_path)
        end
      end

      return false
    end

    def run
      consts_defined  = {}
      consts_referred = {}
      @file_paths.each do |path|
        parser = Constant.new(File.read(path))
        parser.parse
        parser.defined.each do |const|
          consts_defined[const] = path
        end
        parser.referred.each do |const|
          consts_referred[const] ||= []
          consts_referred[const] << path
        end
      end

      dependency = @dependencies.dup
      consts_defined.each do |const, def_path|
        if consts_referred[const]
          consts_referred[const].each do |ref_path|
            if def_path != ref_path
              if cyclic?(dependency, def_path, ref_path)
                # remove cyclic dependencies
                next
              end

              dependency[ref_path] ||= []
              dependency[ref_path] << def_path
              dependency[ref_path].uniq!
            end
          end
        end
      end

      return dependency
    end

    class Constant < Ripper::SexpBuilder
      attr_accessor :defined
      attr_accessor :referred

      def initialize(source)
        @defined  = []
        @referred = []
        super
      end

      def on_const_ref(args)
        args
      end

      def on_var_field(args)
        args
      end

      def on_var_ref(args)
        type, name, position = args
        if type == :@const
          @referred << name
          return [:referred, name]
        end
      end

      def on_const_path_ref(parent, args)
        type, name, position = args
        if type == :@const
          @referred << name
          if parent && parent[0] == :referred
            register_referred_constants(parent[1], name)
          end
        end
        args
      end

      def on_assign(const, *args)
        type, name, position = const
        if type == :@const
          @defined << name
          return [:defined, name]
        end
      end

      def on_module(const, *args)
        handle_module_class_event(const, args)
      end

      def on_class(const, *args)
        handle_module_class_event(const, args)
      end

      def handle_module_class_event(const, *args)
        type, name, position = const
        if type == :@const
          @defined << name
          @referred.delete(name)
          children = args.flatten
          children.each_with_index do |key, i|
            if key == :defined
              register_defined_constants(name, children[i+1])
            end
          end
          return [:defined, name]
        end
      end

      def register_defined_constants(parent, child)
        construct_nest_constants!(@defined, parent, child)
      end

      def register_referred_constants(parent, child)
        construct_nest_constants!(@referred, parent, child)
      end

      def construct_nest_constants!(consts, parent, child)
        nested = []
        consts.each do |const|
          if md = const.match(/^([^:]+)/)
            nested << "#{parent}::#{const}" if md[0] == child
          end
        end
        consts.concat(nested)
      end
    end
  end
end; end