#!/usr/bin/ruby

class ElConfig
  attr_accessor :opt

  def initialize()
    @opt = Hash.new(nil)
  end

  def load()
    lines = IO.readlines("config.txt")

    # allow a second config file (e.g. for developers), but not mandatory 
    # like the first one is
    begin
      lines.push(IO.readlines("config2.txt"))
    rescue SystemCallError
    end
 
    lines.flatten.each do |line|
      # Remove comments (TODO: escape comments with (an even number of) '\')
      line.sub!(/#.*/, "")
      line.strip!

      # Skip blank lines
      next if line == ''

      if line =~ / ^ (.*?) \s* = \s* (.*?) $ /x
        @opt[$1] = eval $2
        if @opt[$1] == :prompt
          print "Need a value for option '"+$1+"': "
          @opt[$1] = gets.chomp
        end
      else
        raise "config.txt:" + $..to_s + ": Each option must be of the form ``option = value''"
      end
    end
    
    @opt.each do |key, value|
      if value == :prompt_end
        print "Need a value for option '"+key+"': "
        @opt[key] = gets.chomp
      end
    end

  end
end