require 'optparse'
# http://www.ruby-doc.org/stdlib/libdoc/optparse/rdoc/classes/OptionParser.html

module RSpec
  module Core

    class ConfigurationOptions
      LOCAL_OPTIONS_FILE  = ".rspec"
      GLOBAL_OPTIONS_FILE = File.join(File.expand_path("~"), ".rspec")
      
      attr_reader :options
      
      def initialize(args)
        @args = args
        @options = parse_options
      end

      def configure(config)
        options.each do |key, value|
          config.send("#{key}=", value) rescue nil
        end
      end

      def drb_argv
        argv = []
        argv << "--color"    if options[:color_enabled]
        argv << "--profile"   if options[:profile_examples]
        argv << "--backtrace" if options[:full_backtrace]
        argv << "--formatter"    << options[:formatter]               if options[:formatter]
        argv << "--line_number"  << options[:line_number]             if options[:line_number]
        argv << "--options_file" << options[:options_file]            if options[:options_file]
        argv << "--example"      << options[:full_description].source if options[:full_description]
        argv + options[:files_or_directories_to_run]
      end

    private

      def parse_options
        command_line_options = parse_command_line_options
        local_options        = parse_local_options(command_line_options)
        global_options       = parse_global_options

        [global_options, local_options, command_line_options].inject do |merged, options|
          merged.merge(options)
        end
      end

      def parse_command_line_options
        options = Parser.parse!(@args)
        options[:files_or_directories_to_run] = @args
        options
      end

      def parse_local_options(options)
        parse_options_file(local_options_file(options))
      end

      def parse_global_options
        parse_options_file(GLOBAL_OPTIONS_FILE)
      end
      
      def parse_options_file(path)
        Parser.parse(args_from_options_file(path))
      end

      def args_from_options_file(path)
        return [] unless File.exist?(path)
        File.readlines(path).map {|l| l.split}.flatten
      end

      def local_options_file(options)
        return options[:options_file] if options[:options_file]
        return LOCAL_OPTIONS_FILE if File.exist?(LOCAL_OPTIONS_FILE)
        RSpec.deprecate("spec/spec.opts", "./.rspec or ~/.rspec", "2.0.0") if File.exist?("spec/spec.opts")
        "spec/spec.opts"
      end
    end
  end
end