Weather info to Ruby object for Japan users

Weather.rb

# -*- encoding:utf-8 -*-
#
# Usage
#
# tokyo = Weather.new :tokyo
# okinawa = Weather.new("沖縄")
# fuchu = Weather.new("東京都府中市")
#
# puts fuchu.get_weather(:today).to_s
# puts fuchu.get_weather(0).to_s
#
# fuchu.each do |i|
#   puts i.to_s
#   puts i.forecast
#   puts i.weather[:max_temp]
#   i.each_pair {|k, v| puts k, v }
# end
#
# tokyo.map{|i| [i.day, i.forecast] }
#
require 'uri'
require 'open-uri'
require 'rss'
require 'nokogiri'

class Weather
  
  include Enumerable

  def initialize(city_name)
    city_name = city_name.to_s if city_name.class == Symbol
    @city_name = city_name
    @area_code = get_area_code(city_name)
    @weathers = set_weathers
    @day_weathers = 
      Array.new(@weathers.size){|n|DayWeather.new(@weathers,@city_name, n)}
  end

  attr_reader :city_name, :area_code, :day_weathers

  public
  def to_hash
    @weathers
  end

  alias to_a to_hash

  def each
    @day_weathers.each do |i|
      yield i
    end
    self
  end

  def get_weather(day = 0)
    begin
      day = day.to_sym if day.class == String
      case day
      when :today
        day = 0
      when :tomorrow
        day = 1
      end
      @day_weathers[day]
    rescue
      raise ArgumentError,
        "unvaild argument '#{day}' for get_weather"
    end
  end

  private
  def set_weathers
    begin
      data = get_weather_data
      data.pop
      weathers = Array.new
      data.each do |words|
        weather = Hash.new
        words.delete!('"')
        weather[:day] = words.slice!(/(.*?):/).delete(':')
        weather[:forecast] = words.slice!(/\s(.*?)\./).delete('.').delete(" ")
        weather[:max_temp] = words.slice!(/(.*?)\./).delete(" ").slice(/(\d+)/)
        weather[:rain] = words.slice(/(\d+)/)
        weathers << weather
      end
      weathers
    rescue
      raise StandardError,
        "the MSN weather sever may be downed, or something wrong"
    end
  end

  def get_area_code(city_name)
    uri = URI.encode("http://weather.service.msn.com/find.aspx?outputview=search&weadegreetype=C&culture=ja-JP&weasearchstr=#{city_name}")
    doc = Nokogiri::XML(open(uri))
    begin 
      code = doc.xpath('//weather').attr('weatherlocationcode').value
    rescue
      raise ArgumentError,
        "invaild city name '#{city_name}'!"
    end
    area_code = code.slice(3..-1)
  end


  def get_weather_data
    begin
      uri = URI.parse("http://weather.jp.msn.com/RSS.aspx?wealocations=wc:#{@area_code}&weadegreetype=C&culture=ja-JP")
      rss = RSS::Parser.parse(uri, false)
      str = rss.channel.item(0).description
      remove_html_tag(str).split(/%/)
    rescue
      raise StandardError,
        "the MSN weather sever may be downed, or got invaild city code"
    end
  end

  def remove_html_tag(string)
    string.gsub!(/<(\"[^\"]*\"|'[^']*'|[^'\">])*>/,'""')
  end

  class DayWeather

    include Enumerable

    def initialize(weathers, city_name, day)
      @weather = weathers[day]
      @city_name = city_name
    end

    attr_reader :city_name

    def to_hash
      @weather
    end

    def each
      @weather.each {|_k, v| yield v }
    end

    def each_pair
      @weather.each_pair {|k,v| yield k, v }
    end

    def inspect
      word = "\#<DayWeather:@city_name = #{city_name}, "
      word << "@day=#{day}, @forecast=#{forecast}, "
      word << "@max_temp=#{max_temp}, @rain=#{rain}>"
      word
    end

    def to_s
      word = "#{city_name}の"
      word << "#{day}の天気は"
      word << "#{forecast}、"
      word << "最高気温#{max_temp}度、"
      word << "降水確率は#{rain}%です。"
      word
    end

    def method_missing(key)
      @weather[key]
    end
  end
end

参考にしたぺーじ http://wuvu.net/?p=233