require 'digest/md5'
require "optparse"

module Keystone::Batch
  #
  # = バッチをざくっと書きたい時用モジュール
  # 
  # 基本的にはexecuteメソッドにバッチ処理をブロックで渡す
  #
  # == 定数
  #
  # ERROR_MAIL_TO （エラーメール送信先） 設定しておけば自動でエラーメールを送信してくれる
  #
  # ERROR_MAIL_FROM （エラーメール送信元） 設定されてない場合はERROR_MAIL_TOを使用
  #
  # ERROR_MAIL_STMP_ADDR （エラーメール送信SMTPアドレス） 設定されてない場合は"127.0.0.1"
  #
  # ERROR_MAIL_STMP_PORT （エラーメール送信SMTPポート） 設定されてない場合は25
  #
  module Base
    def option_parser
      @options ||= OptionParser.new
    end
    
    # [options]
    #   プログラムより指定するバッチ動作オプション（ハッシュ値）
    #   :error_mail_to
    #   :error_mail_from
    #   :error_mail_smtp_addr
    #   :error_mail_smtp_port
    #   :double_process_check
    #   :auto_recover
    #
    # バッチの主処理をこのメソッドへのブロック引数として定義してください
    #
    #   require 'rubygems'
    #   require 'keystone'
    #
    #   include Keystone::Batch::Base
    #
    #   execute() do
    #     info "batch process01"
    #   end
    #
    # railsのscript/runnerで使用する場合はscript/runnerを以下の感じでいじってから使用してください
    #
    #   #!/usr/bin/env ruby
    # 
    #   #original add start
    #   ARGV_ORIGINAL = ARGV.clone
    #   ARGV.delete("-h")
    #   ARGV.delete("--help")
    #   #original add end
    # 
    #   require File.dirname(__FILE__) + '/../config/boot'
    #   require 'commands/runner'
    #
    def execute(options={},&process)
      
      options[:error_mail_to] = nil unless options.key?(:error_mail_to)
      options[:error_mail_from] = nil unless options.key?(:error_mail_from)
      options[:error_mail_smtp_addr] = "127.0.0.1" unless options.key?(:error_mail_smtp_addr)
      options[:error_mail_smtp_port] = 25 unless options.key?(:error_mail_smtp_port)
      options[:double_process_check] = true unless options.key?(:double_process_check)
      options[:auto_recover] = true unless options.key?(:auto_recover)

      double_process_check = options[:double_process_check]
      auto_recover         = options[:auto_recover]

      opts = option_parser()
      pg_path = nil
      if Module.constants.include?("ARGV_ORIGINAL")
        
        debug "ARGV_ORIGINAL found!!"
        
        ARGV << "-h" if ARGV_ORIGINAL.include?("-h")
        ARGV << "--help" if ARGV_ORIGINAL.include?("--help")
        script_name = File.basename(ARGV_ORIGINAL[0])
        pg_path = File.expand_path(script_name)
        opts.banner = "Usage: script/runner #{script_name} [options]"
        
        debug "pg_path=#{pg_path}"

        opts.on("-e", "--environment=name", 
          String,"specifies the environment for the runner to operate under (test/development/production).",
          "default: development")
      else
        debug "caller=#{caller}"
        pg_path = if File.expand_path(caller[0]) =~ /(.*):\d*\z/
          $1
        else
          raise "must not happen!! can not get caller value"
        end
      end

      opts.on("-h","--help","show this help message.") { $stderr.puts opts; exit }

      pid_file = nil
      opts.on("--lockfile LOCK_FILE_PATH","set lock file path") do |v|
        double_process_check = true unless double_process_check
        pid_file = v 
      end
      opts.on("--double_process_check_off","disable double process check") do |v|
        double_process_check = false
      end
      opts.on("--auto_recover_off","disable auto recover mode") do |v|
        auto_recover = false
      end
      opts.on("--error_mail_to MAIL_ADDR") do |v|
        options[:error_mail_to] = v
      end
      opts.on("--error_mail_from MAIL_ADDR") do |v|
        options[:error_mail_from] = v
      end
      opts.on("--error_mail_smtp_addr IP_ADDR") do |v|
        options[:error_mail_smtp_addr] = v
      end
      opts.on("--error_mail_smtp_port PORT") do |v|
        options[:error_mail_smtp_port] = Integer(v)
      end
      
      opts.parse!(ARGV)
      
      info "start script(#{pg_path})"
      script_started_at = Time.now
      double_process_check_worked = false
      begin
        # double process check
        if double_process_check
          #pg_path = File.expand_path($0)
          pg_name = File.basename(pg_path)
          hash = Digest::MD5.hexdigest(pg_path)
          pid_file = "/tmp/.#{pg_name}.#{hash}.pid" unless pid_file
          debug pid_file
          if File.exists?(pid_file)
            pid = File.open(pid_file).read.chomp
            pid_list = `ps -e | awk '{print $1}'`
            if (pid != nil && pid != "" ) && pid_list =~ /#{pid}/
              warn "pid:#{pid} still running"
              double_process_check_worked = true
              return nil
            else
              if auto_recover
                warn "lock file still exists[pid=#{pid}],but process does not found.auto_recover enabled.so process continues"
              else
                double_process_check_worked = true
                raise "lock file still exists[pid=#{pid}],but process does not found.auto_recover disabled.so process can not continue"
              end
            end
          end
          File.open(pid_file, "w"){|file|
            file.write $$
          }
        end
        return (yield process)
      rescue => e
        error e
        send_error_mail(e,options)
      ensure
        unless double_process_check_worked
          File.delete(pid_file) if double_process_check
        end
        info "finish script (%1.3fsec)" % (Time.now - script_started_at)
      end
    end
    
    #
    # = エラーメール送信メソッド
    #  エクセプションを何も考えずにメールにて送信する
    # 　各種メール送信属性は定数にて渡す
    #
    # [exception]
    #   エクセプションクラスインスタンス
    #
    def send_error_mail(exception,options)
      if options[:error_mail_to]
        host = Keystone::Os.get()
        title = %|error occur at "#{host.hostname}" [#{exception.message}]|
        
        mail_to = options[:error_mail_to]
        mail_to = [mail_to] if mail_to.is_a?(String)
        mail_from = options[:error_mail_from] ?  options[:error_mail_from] : mail_to[0]
        smtp_addr = options[:error_mail_smtp_addr]
        smtp_port = options[:error_mail_smtp_port]
        
        debug "mail_to=#{mail_to}"
        debug "mail_from=#{mail_from}"
        debug "smtp_addr=#{smtp_addr}"
        debug "smtp_port=#{smtp_port}"
        
        body  = <<-BODY
==== error message ====
#{exception.message}
====== backtrace ======
#{exception.backtrace.join("\n")}
===== environment =====
#{host.dump}
BODY
        Keystone::Mail::Send.send(mail_from,mail_to,title,body,{:smtp_addr=>smtp_addr,:smtp_port=>smtp_port})
      else
        warn "ERROR_MAIL_TO not defined.if you want error mail automatically,set this value."
      end
    end
  end
end