注意点。

• 使いかたについての質問は一切受けつけません。そのようなコメントは削除します。
• 使った結果について何が起ころうと責任は一切負いません。

そのうち GitHub か coderepos あたりに投げます。

#!/usr/bin/ruby
# -*- mode:ruby; coding:utf-8 -*-
$KCODE = 'u'

require 'rubygems'
require 'mechanize'
require 'logger'
require 'tempfile'
require 'fileutils'
require 'nkf'

#
# SEGA の三国志大戦公式サイトへアクセスするライブラリ.
#
class Enbujyo
  attr_accessor :mail, :password
  attr_reader :agent

  class LoginError < RuntimeError; end

  def initialize(agent = nil)
    @agent = agent 
    unless @agent
      @agent = WWW::Mechanize.new
      @agent.user_agent_alias = 'Mac Safari'
    end
  end

  def login
    page = @agent.get('http://enbujyo.3594t.com/')
    @agent.page.form_with(:action => '/action.cgi') {|f|
      f.field_with(:name => 'mail').value = @mail
      f.field_with(:name => 'password').value = @password
      f.click_button
    }
    raise LoginError if /error/i =~ @agent.page.uri.to_s
  end

  def download_selection(movie_type = 's')
    movie_date = (Time.now - 60*60*17).strftime("%Y%m%d")  # 17時で切り替え/JST前提
    @agent.get('http://enbujyo.3594t.com/members/selection/index.html')
    login if /エラー/ =~ @agent.page.title 

    tmpname = "_enbujyo_download.#{random_string}.wmv"
    open(tmpname, 'w'){|tmp|
      tmp.print @agent.get_file("http://download.enbujyo.3594t.com/selection_download.cgi?date=#{movie_date}&type=#{movie_type}")
    }
    filename = "selection_#{movie_date}.wmv"
    if @agent.page.response['content-disposition']
      /filename="(.*\.wmv)"/ =~ @agent.page.response['content-disposition']
      filename = windows? ? $1 : NKF.nkf('-Sw', $1)
    end
    FileUtils.mv(tmpname, filename)
    puts "Downloading #{filename} has finished."
  end

  private
  def random_string(length = 10, strings = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789')
    Array.new(length).map{ strings[rand(strings.size),1] }.join
  end

  def windows?
    RUBY_PLATFORM.downcase =~ /mswin(?!ce)|mingw|cygwin|bccwin/
  end
end

if $0 == __FILE__
  enbu = Enbujyo.new
  enbu.mail = 'LOGINMAILADDRESS'
  enbu.password = 'YOURPASSWORD'
  #enbu.agent.log = Logger.new($stdout) # DEBUG
  enbu.download_selection
end