# encoding: utf-8
require 'open_classes/object'

# Array
class Array
  # Arrays loop together.
  #
  #   alpha = %w{one two three}
  #   numbers = %w{1 2 3}
  #   [alpha, numbers].together do |first, second|
  #     print "#{first}:#{second}\n"  # => output one:1, two:2, three:3
  #   end
  def together
    if_not_contain_array_rails_type_error
    first.each_with_index do |i_v, i|
      eval_each_str = get_args_str_for_together i
      instance_eval "yield(#{eval_each_str})"
    end
  end

  # Arrays loop together with index.
  #
  #   alpha = %w{one two three}
  #   numbers = %w{1 2 3}
  #   [alpha, numbers].together_with_index do |first, second, index|
  #     print "#{index.to_s}:#{first}:#{second}\n"  # => output 0:one:1, 1:two:2, 2:three:3
  #   end
  def together_with_index
    if_not_contain_array_rails_type_error
    first.each_with_index do |i_v, i|
      eval_each_str = get_args_str_for_together i, true
      instance_eval "yield(#{eval_each_str})"
    end
  end

  # Arrays together map.
  #
  # together_map has aliases [:tmap, :together_collect, :tcollect]
  #
  # if you want to single Array return
  #   alpha = %w{one two three}
  #   numbers = %w{1 2 3}
  #   print [alpha, numbers].together_map do |first, second|
  #     "#{first}:#{second}\n"
  #   end # => output one:1, two:2, three:3
  #
  # if you want to multi Array return
  #   alpha = %w{one two three}
  #   numbers = %w{1 2 3}
  #   print [alpha, numbers].together_map do |first, second|
  #     ["#{first}:#{second}", "#{second}:#{first}"]
  #   end # => output [['1:one', '2:two', '3:three'], ['one:1', 'two:2', 'three:3']]
  def together_map
    if_not_contain_array_rails_type_error
    ret = []
    first.each_with_index do |i_v, i|
      eval_each_str = get_args_str_for_together i
      each_ret = instance_eval "yield(#{eval_each_str})"
      ret = set_together_each_return(ret, each_ret, i)
    end
    ret
  end

  alias_method :together_collect, :together_map
  alias_method :tmap, :together_map
  alias_method :tcollect, :together_map

  private

  def if_not_contain_array_rails_type_error
    each { |f|fail TypeError, "you have to use [Array1, Array2, ...] | #{f.class} is invalid" unless f.class == Array }
  end

  def get_args_for_together(i)
    eval_each = []
    each_with_index { |j_v, j|eval_each << "self[#{j}][#{i}]" }
    eval_each
  end

  def get_args_str_for_together(i, with_index = false)
    each_eval = with_index ? get_args_for_together(i) << i : get_args_for_together(i)
    each_eval.join(',')
  end

  def set_together_each_return(ret, each_ret, index)
    if together_return_multi?(each_ret)
      size.times { |i|ret << [] } if index == 0
      (0..(size - 1)).each { |i|ret[i] << each_ret[i] }
    else
      ret << each_ret
    end
    ret
  end

  def together_return_multi?(list)
    (list.class == Array && list.size == size).to_bool
  end
end