#!/usr/bin/env ruby
#
# Copyright (C) 2008-2011  Kouhei Sutou <kou@clear-code.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

require 'English'
require 'pathname'
require 'fileutils'
require 'time'
require 'optparse'
require 'erb'
require 'tempfile'

begin
  require 'RRD' unless Object.const_defined?(:RRD)
rescue LoadError
  module RRD
    module_function
    def method_missing(method_name, *args)
      run(method_name.to_s, *args)
    end

    def last(file)
      Time.at(Integer(run("last", file)))
    end

    def info(file)
      _info = {}
      run("info", file).each_line do |line|
        key, value = line.split(/\s*=\s*/)
        _info[key] = value.strip
      end
      _info
    end

    def run(command, *args)
      command_line = ["rrdtool", command] + args.collect {|arg| arg.to_s}

      stdin_pipe = IO.pipe
      stdout_pipe = IO.pipe
      stderr_pipe = IO.pipe

      pid = fork do
        stdin_pipe[1].close
        STDIN.reopen(stdin_pipe[0])
        stdin_pipe[0].close

        stdout_pipe[0].close
        STDOUT.reopen(stdout_pipe[1])
        stdout_pipe[1].close

        stderr_pipe[0].close
        STDERR.reopen(stderr_pipe[1])
        stderr_pipe[1].close

        exec(*command_line)
        exit!(1)
      end

      stdin_pipe[0].close
      stdout_pipe[1].close
      stderr_pipe[1].close
      _, status = Process.waitpid2(pid)

      stdout = stdout_pipe[0].read
      stderr = stderr_pipe[0].read
      [stdin_pipe[1], stdout_pipe[0], stderr_pipe[0]].each do |pipe|
        pipe.close unless pipe.closed?
      end

      unless status.success?
        raise "failed to run: #{command_line.join(' ')}: #{stderr}"
      end
      stdout
    end
  end
end

module RRD
  module_function
  def last_update_time(file)
    time = last(file)
    if time and time < Time.at(0)
      time = Time.at(Integer(`rrdtool last '#{file}'`))
    end
    time
  end
end

class MilterManagerLogAnalyzer
  module GraphData
    class TimeRange
      def initialize(step, rows)
        @step = step
        @rows = rows
      end

      def tag
        name.downcase
      end

      def steps
        base_range.steps * n_times
      end

      def start_time
        base_range.start_time * n_times
      end
    end

    class DayRange < TimeRange
      def name
        "Day"
      end

      def steps
        (3600 * 24) / (@step * @rows) + 1
      end

      def start_time
        -(60 * 60 * 24)
      end
    end

    class WeekRange < TimeRange
      def name
        "Week"
      end

      private
      def base_range
        DayRange.new(@step, @rows)
      end

      def n_times
        7
      end
    end

    class MonthRange < TimeRange
      def name
        "Month"
      end

      private
      def base_range
        WeekRange.new(@step, @rows)
      end

      def n_times
        5
      end
    end

    class YearRange < TimeRange
      def name
        "Year"
      end

      private
      def base_range
        MonthRange.new(@step, @rows)
      end

      def n_times
        12
      end
    end

    class Data
      def initialize(counts)
        @counts = counts
      end

      def empty?
        return true unless @counts
        @counts.each_value do |counting|
          return false unless counting.empty?
        end
        true
      end

      def last_time
        last_time = 0
        @counts.each_value do |count|
          next if count.empty?
          _last_time = count.keys.sort.last
          last_time = [last_time, _last_time].max
        end
        last_time || 0
      end

      def first_time
        first_time = nil
        @counts.each_value do |count|
          next if count.empty?
          _first_time = count.keys.sort.first
          first_time ||= _first_time
          first_time = [first_time, _first_time].min
        end
        first_time
      end

      def [](key)
        @counts[key]
      end

      def []=(key, value)
        @counts[key] = value
      end
    end
  end

  class GraphGenerator
    attr_reader :last_update_time
    def initialize(output_directory, update_time=nil)
      @output_directory = output_directory
      @data = []
      @items = nil
      @title = nil
      @vertical_label = nil
      @step = 60 # seconds
      @width = 600
      @points_per_sample = 3

      @update_time = normalize_time(update_time)

      @old_base_rrd_file_names = []

      @last_update_time = nil
    end

    def rows
      @width / @points_per_sample
    end

    def rrd_file
      build_path(self.class.base_rrd_file_name)
    end

    def build_path(*paths)
      File.join(*([@output_directory, *paths].compact))
    end

    def prepare
      migrate_if_needed

      if File.exist?(rrd_file)
        @last_update_time = normalize_time(RRD.last_update_time(rrd_file))
        @current_time = @last_update_time.to_i + @step
      else
        @last_update_time = nil
        @current_time = nil
      end
      @data = {}
    end

    def feed(time_stamp, content)
      time_stamp = normalize_time(time_stamp)
      return if @last_update_time and time_stamp < @last_update_time
      return if time_stamp >= @update_time

      time_stamp = time_stamp.to_i
      data = []
      find_data(content) do |key, type, options|
        data << [key, type, options]
      end
      return if data.empty?

      @current_time ||= time_stamp
      if time_stamp and @current_time > time_stamp
        @data = {}
      else
        flush(time_stamp)
        update_data(data)
      end
    end

    def flush(next_time_stamp=nil)
      return if @current_time == next_time_stamp
      create_rrd(rrd_file, @current_time, *@items) unless File.exist?(rrd_file)

      start_time = @current_time
      unless @data.empty?
        counts = []
        @items.each do |item|
          counts << @data[item]
        end
        RRD.update(rrd_file, "#{@current_time}:#{counts.join(':')}")
        start_time += @step
      end
      @data = {}

      if next_time_stamp
        fill_no_data_span(rrd_file, start_time, next_time_stamp, @items.size)
      end
      @current_time = next_time_stamp || @current_time
    end

    def fill_no_data_span(file, start_time_stamp, end_time_stamp, n_items)
      start_time_stamp.step(end_time_stamp - @step, @step) do |time_stamp|
        empty_data = ([nil] * n_items).join(":")
        RRD.update(file, "#{time_stamp}:#{empty_data}")
      end
    end

    def output_graph(range_class, options={}, *args)
      return nil unless File.exist?(rrd_file)
      last_update_time = RRD.last_update_time(rrd_file)

      range = range_class.new(@step, rows)
      start_time = options[:start_time] || range.start_time
      end_time = options[:end_time] || guess_end_time(start_time)
      graph_tag = options[:graph_tag] || range.tag
      width = options[:width] || @width
      height = options[:height] || 200

      vertical_label = "#{@vertical_label}/#{unit}"
      name = graph_name(graph_tag)

      items = @items.inject([]) do |_items, item|
        _items + generate_definitions(rrd_file, range, item)
      end

      data = items + args
      data << "COMMENT:[#{last_update_time.iso8601.gsub(/:/, '\:')}]\\r"
      RRD.graph(name,
                "--title", @title,
                "--vertical-label", vertical_label,
                "--start", start_time.to_s,
                "--end", end_time.to_s,
                "--width", width.to_s,
                "--height", height.to_s,
                "--alt-y-grid",
                "--units-exponent", "0",
                *data)
      [name, @title]
    end

    private
    def create_rrd(file, start_time, *sources)
      ranges = [
                GraphData::DayRange.new(@step, rows),
                GraphData::WeekRange.new(@step, rows),
                GraphData::MonthRange.new(@step, rows),
                GraphData::YearRange.new(@step, rows),
               ]

      rra = []
      ranges.each do |range|
        rra << "RRA:MAX:0.5:#{range.steps}:#{rows}"
        rra << "RRA:AVERAGE:0.5:#{range.steps}:#{rows}"
        rra << "RRA:LAST:0.5:#{range.steps}:#{rows}"
      end

      data_sources = sources.collect do |source|
        "DS:#{source}:GAUGE:#{heartbeat}:0:U"
      end

      RRD.create(file,
                 "--start", (start_time - 1).to_i.to_s,
                 "--step", @step,
                 *(rra + data_sources))
    end

    def heartbeat
      @step * 3
    end

    def recreate_rrd(*new_items)
      dump_file = Tempfile.new("milter-manager-log-analyzer")
      RRD.dump(rrd_file, dump_file.path)
      data = dump_file.read
      data.gsub!(/<last_ds><\/last_ds>/, "<last_ds>NaN</last_ds>")
      data.sub!(/<!-- Round Robin Archives -->/) do |text|
        ds = ""
        new_items.each do |item|
          ds << <<-EODS
       <ds>
               <name> #{item} </name>
               <type> GAUGE </type>
               <minimal_heartbeat> #{@step * 3} </minimal_heartbeat>
               <min> 0.0000000000e+00 </min>
               <max> NaN </max>

               <!-- PDP Status -->
               <last_ds> NaN </last_ds>
               <value> 0.0000000000e+00 </value>
               <unknown_sec> 0 </unknown_sec>
       </ds>
EODS
        end
        ds + text
      end

      data.gsub!(/<\/cdp_prep>/) do |text|
        ds = ""
        new_items.each do |item|
          ds << <<-EODS
                        <ds>
                        <primary_value> 0.0000000000e+00 </primary_value>
                        <secondary_value> 0.0000000000e+00 </secondary_value>
                        <value> 0.0000000000e+00 </value>
                        <unknown_datapoints> 0 </unknown_datapoints>
                        </ds>
EODS
        end
        ds + text
      end

      data.gsub!(/<\/row>/) do |text|
        ("<v> NaN </v>" * new_items.size) + text
      end

      dump_file.open
      dump_file.rewind
      dump_file.print(data)
      dump_file.close

      new_rrd_file = rrd_file + ".new"
      FileUtils.rm_f(new_rrd_file)
      RRD.restore(dump_file.path, new_rrd_file)
      FileUtils.mv(new_rrd_file, rrd_file)
    end

    def migrate_if_needed
      history = @old_base_rrd_file_names.collect do |base_rrd_file_name|
        build_path(base_rrd_file_name)
      end + [rrd_file]
      history.each_with_index do |file_name, i|
        next unless File.exist?(file_name)
        next_file_name = history[i + 1]
        if next_file_name and !File.exist?(next_file_name)
          FileUtils.mv(file_name, next_file_name)
        end
      end

      return unless File.exist?(rrd_file)

      data_names = []
      RRD.info(rrd_file).each do |key, value|
        main, = key.split(/\./)
        case main
        when /\Ads\[(.+?)\]\z/
          data_names << $1
        end
      end
      data_names = data_names.uniq
      if data_names.size < @items.size
        recreate_rrd(*@items[(data_names.size)..-1])
      elsif data_names.size > @items.size
        raise "data source can't be removed!"
      end
    end

    def guess_end_time(start_time)
      if start_time.is_a?(String)
        "now"
      else
        end_time = Time.now.to_i
        step = start_time.abs * @points_per_sample / @width
        end_time - (end_time % step)
      end
    end

    def normalize_time(time)
      Time.at(time.to_i - time.to_i % @step).utc
    end

    def generate_definitions(rrd_file, range, item, label=nil)
      label ||= item
      [
       "DEF:#{label}=#{rrd_file}:#{item}:AVERAGE",
       "DEF:max_#{label}=#{rrd_file}:#{item}:MAX",
       "CDEF:n_#{label}=#{label}",
       "CDEF:real_#{label}=#{label}",
       "CDEF:real_max_#{label}=max_#{label}",
       "CDEF:real_n_#{label}=n_#{label},#{range.steps},*",
       "CDEF:total_#{label}=PREV,UN,real_n_#{label},PREV,IF,real_n_#{label},+",
      ]
    end

    def unit
      case @step
      when 60
        "min"
      when 60 * 60
        "hour"
      when 60 * 60 * 24
        "day"
      when 60 * 60 * 24 * 365
        "year"
      else
        "unknown"
      end
    end

    def update_data(data)
      data.each do |key, type, options|
        type ||= :count
        options ||= {}
        count = options[:count] || 1
        @data[key] ||= 0
        case type
        when :count
          @data[key] += count
        when :max
          @data[key] = [@data[key], count].max
        end
      end
    end
  end

  class SessionGraphGenerator < GraphGenerator
    class << self
      def base_rrd_file_name
        "session.rrd"
      end
    end

    def initialize(output_directory, update_time)
      super(output_directory, update_time)
      @title = 'Sessions'
      @vertical_label = "sessions"
      @items = ["smtp", "child", "disconnected", "concurrent"]
      @old_base_rrd_file_names = ["milter-log.session.rrd"]
    end

    def graph_name(tag)
      build_path("session.#{tag}.png")
    end

    def find_data(content)
      case content
      when /\A\[milter\]\[end\]\[(.+?)\]\[(.+?)\]\[(.+?)\]\((.+?)\): (.+)\z/
        state = $1
        status = $2
        elapsed = $3
        id = $4
        name = $5
        yield("child")
      when /\A\[milter\]\[end\]\[(.+)\]\(.+\): (.+)\z/
        elapsed = $1
        id = $2
        name = $3
        yield("child")
      when /\A\[session\]\[end\]\[(.+)\]\[(.+)\]\[(.+)\]\(.+\)\z/
        state = $1
        status = $2
        elapsed = $3
        id = $4
        yield("smtp")
      when /\A\[session\]\[end\]\[(.+)\]\(.+\)\z/
        elapsed = $1
        id = $2
        yield("smtp")
      when /\A\[session\]\[disconnected\]\[(.+)\]\(.+\)\z/
        elapsed = $1
        id = $2
        yield("disconnected")
      when /\A\[sessions\]\[finished\] (\d+)\(\+(\d+)\) (\d+)\z/
        n_processed = $1
        n_finished = $2
        n_rest = $3
        yield("concurrent", :max, :count => n_rest.to_i)
      end
    end

    def output_graph(range_class, options={})
      super(range_class, options,
            "AREA:n_smtp#0000ff:SMTP        ",
            "GPRINT:total_smtp:MAX:total\\: %8.0lf sessions",
            "GPRINT:smtp:AVERAGE:avg\\: %6.2lf sessions/#{unit}",
            "GPRINT:max_smtp:MAX:max\\: %4.0lf sessions/#{unit}\\l",
            "LINE2:n_child#00ff00:milter      ",
            "GPRINT:total_child:MAX:total\\: %8.0lf sessions",
            "GPRINT:child:AVERAGE:avg\\: %6.2lf sessions/#{unit}",
            "GPRINT:max_child:MAX:max\\: %4.0lf sessions/#{unit}\\l",
            "LINE2:n_disconnected#ff0000:Disconnected",
            "GPRINT:total_disconnected:MAX:total\\: %8.0lf sessions",
            "GPRINT:disconnected:AVERAGE:avg\\: %6.2lf sessions/#{unit}",
            "GPRINT:max_disconnected:MAX:max\\: %4.0lf sessions/#{unit}\\l",
            "LINE2:n_concurrent#cc00cc:Concurrent",
            "GPRINT:total_concurrent:MAX:total\\: %8.0lf sessions",
            "GPRINT:concurrent:AVERAGE:avg\\: %6.2lf sessions/#{unit}",
            "GPRINT:max_concurrent:MAX:max\\: %4.0lf sessions/#{unit}\\l")
    end
  end

  class MilterManagerStatusGraphGenerator < GraphGenerator
    class << self
      def base_rrd_file_name
        "milter-manager.status.rrd"
      end
    end

    def initialize(output_directory, update_time)
      super(output_directory, update_time)
      @vertical_label = "sessions"
      @title = 'milter manager: status'
      @items = ["pass",
                "accept",
                "reject",
                "discard",
                "temporary-failure",
                "quarantine",
                "abort",
                "error"]
      @old_base_rrd_file_names = ["milter-log.mail.rrd", "milter-manager.rrd"]
    end

    def graph_name(tag)
      build_path("milter-manager.status.#{tag}.png")
    end

    def output_graph(range_class, options={})
      entries = graph_entries
      smtp_label = "SMTP"
      disconnected_label = "Disconnected"
      concurrent_label = "Concurrent"
      labels = entries.collect {|_, _, _, label| label}
      labels << smtp_label << disconnected_label << concurrent_label
      max_label_size = labels.collect {|label| label.size}.max

      items = []
      entries.each do |type, name, color, label|
        items << "#{type}:#{name}#{color}:#{label.ljust(max_label_size)}"
        items << "GPRINT:total_#{name}:MAX:total\\: %8.0lf sessions"
        items << "GPRINT:#{name}:AVERAGE:avg\\: %6.2lf sessions/#{unit}"
        items << "GPRINT:max_#{name}:MAX:max\\: %4.0lf sessions/#{unit}\\l"
      end

      range = range_class.new(@step, rows)
      path = build_path(SessionGraphGenerator.base_rrd_file_name)
      items += generate_definitions(path, range, "smtp")
      items += generate_definitions(path, range, "disconnected")
      items += generate_definitions(path, range, "concurrent")

      label = smtp_label.ljust(max_label_size)
      items << "LINE2:n_smtp#000000:#{label}"
      items << "GPRINT:total_smtp:MAX:total\\: %8.0lf sessions"
      items << "GPRINT:smtp:AVERAGE:avg\\: %6.2lf sessions/#{unit}"
      items << "GPRINT:max_smtp:MAX:max\\: %4.0lf sessions/#{unit}\\l"

      label = disconnected_label.ljust(max_label_size)
      items << "LINE2:n_disconnected#999999:#{label}"
      items << "GPRINT:total_disconnected:MAX:total\\: %8.0lf sessions"
      items << "GPRINT:disconnected:AVERAGE:avg\\: %6.2lf sessions/#{unit}"
      items << "GPRINT:max_disconnected:MAX:max\\: %4.0lf sessions/#{unit}\\l"

      label = concurrent_label.ljust(max_label_size)
      items << "LINE2:n_concurrent#9999ff:#{label}"
      items << "GPRINT:total_concurrent:MAX:total\\: %8.0lf sessions"
      items << "GPRINT:concurrent:AVERAGE:avg\\: %6.2lf sessions/#{unit}"
      items << "GPRINT:max_concurrent:MAX:max\\: %4.0lf sessions/#{unit}\\l"
      super(range_class, options, *items)
    end

    private
    def find_data(content)
      case content
      when /\A\[session\]\[end\]\[(.+)\]\[(.+)\]\[(.+)\]\((.+)\)\z/
        state = $1
        status = $2
        elapsed = $3
        id = $4
        yield(status)
      when /\A\[reply\]\[(.+)\]\[(.+)\]\z/
        state = $1
        status = $2
        return if status == "continue" and state != "end-of-message"
        status = "pass" if status == "continue"
        yield(status)
      when /\A\[abort\]\[(.+)\]\z/
        state = $1
        status = "abort"
        yield(status)
      end
    end

    def graph_entries
      [
       ["AREA", "pass", "#0000ff", "Pass"],
       ["STACK", "accept", "#00ff00", "Accept"],
       ["STACK", "reject", "#ff0000", "Reject"],
       ["STACK", "discard", "#ffd400", "Discard"],
       ["STACK", "temporary-failure", "#888888", "Temp-Fail"],
       ["STACK", "quarantine", "#a52a2a", "Quarantine"],
       ["STACK", "abort", "#ff9999", "Abort"],
       ["STACK", "error", "#ff00ff", "Error"],
      ]
    end
  end

  class MilterManagerReportGraphGenerator < GraphGenerator
    class << self
      def base_rrd_file_name
        "milter-manager.report.rrd"
      end
    end

    def initialize(output_directory, update_time)
      super(output_directory, update_time)
      @vertical_label = "mails"
      @title = 'milter manager: report'
      @items = ["spam",
                "virus",
                "uribl",
                "greylisting-pass",
                "spf-pass",
                "spf-fail",
                "sender-id-pass",
                "sender-id-fail",
                "dkim-pass",
                "dkim-fail",
                "dkim-adsp-pass",
                "dkim-adsp-fail",
                "tarpitting-pass"]
      @old_base_rrd_file_names = []
    end

    def graph_name(tag)
      build_path("milter-manager.report.#{tag}.png")
    end

    def output_graph(range_class, options={})
      entries = [
                 ["AREA", "spam", "#ff0000", "spam"],
                 ["STACK", "virus", "#ddbb00", "Virus"],
                 ["STACK", "uribl", "#dd00bb", "URIBL"],
                 ["STACK", "greylisting-pass", "#888888", "Greylisting (pass)"],
                 ["STACK", "tarpitting-pass", "#000088", "Tarpitting (pass)"],
                 ["STACK", "spf-pass", "#33cc33", "SPF (pass)"],
                 ["STACK", "spf-fail", "#cc3333", "SPF (fail)"],
                 ["STACK", "sender-id-pass", "#33cccc", "Sender ID (pass)"],
                 ["STACK", "sender-id-fail", "#cccc33", "Sender ID (fail)"],
                 ["STACK", "dkim-pass", "#3366cc", "DKIM (pass)"],
                 ["STACK", "dkim-fail", "#cc6633", "DKIM (fail)"],
                 ["STACK", "dkim-adsp-pass", "#3399cc", "DKIM ADSP (pass)"],
                 ["STACK", "dkim-adsp-fail", "#cc9933", "DKIM ADSP (fail)"],
                ]
      max_label_size = entries.collect {|_, _, _, label| label.size}.max

      items = []
      entries.each do |type, name, color, label|
        items << "#{type}:#{name}#{color}:#{label.ljust(max_label_size)}"
        items << "GPRINT:total_#{name}:MAX:total\\: %8.0lf mails"
        items << "GPRINT:#{name}:AVERAGE:avg\\: %6.2lf mails/#{unit}"
        items << "GPRINT:max_#{name}:MAX:max\\: %4.0lf mails/#{unit}\\l"
      end
      super(range_class, options, *items)
    end

    private
    def find_data(content, &block)
      case content
      when /\A\[milter\]\[header\]\[add\]\((.+)\): <(.+?)>=<(.+?)>: (.+)\z/
        id = $1
        name = $2
        value = $3
        milter_name = $4
        report_key(name, value, milter_name, &block)
      end
    end

    def report_key(header_name, header_value, milter_name, &block)
      case header_name
      when /\AX-Spam-Flag\z/i
        parse_x_spam_flag(header_value, &block)
      when /\AX-Spam-Status\z/i
        parse_x_spam_status(header_value, &block)
      when /\AAuthentication-Results\z/i
        parse_authentication_results(header_value, &block)
      when /\AX-Greylist\z/i
        parse_x_greylist(header_value, &block)
      when /\AX-Virus-Status\z/i
        parse_x_virus_status(header_value, &block)
      end
    end

    def parse_x_spam_flag(value)
      case value
      when /\Ayes\z/i
        yield("spam")
      end
    end

    def parse_x_spam_status(value)
      return unless /tests=/ =~ value
      uribl_used = false
      results = $POSTMATCH.split(/\s*\S+=/, 2)[0].split(/\s*,\s*/)
      results.each do |result|
        case result
        when /\AURIBL_/i
          unless uribl_used
            yield("uribl")
            uribl_used = true
          end
        end
      end
    end

    # TODO: fix this method.
    #   see below urls to know formal definition of "Authentication-Results" header.
    #   see section 2.2. of RFC5451 and section 3.2.2, 3.2.3 of RFC5322.
    #   http://www.ietf.org/rfc/rfc5451.txt
    #   http://www.ietf.org/rfc/rfc5322.txt
    def parse_authentication_results(value)
      id, *results = value.split(/;\s*/)
      results.each do |result|
        if /\A(\S+?)=(\S+)\s*/ =~ result
          type = $1
          result = $2
          other_info = $POSTMATCH
          case result
          when "pass"
            yield("#{type}-pass")
          when "fail", "hardfail"
            yield("#{type}-fail")
          when "neutral"
            yield("#{type}-fail") if /\A\(verification failed\)/ =~ other_info
          end
        end
      end
    end

    def parse_x_greylist(value)
      case value
      when /Message whitelisted by tarpit (\d+)s/i
        tarpit_second = $1.to_i
        yield("tarpitting-pass")
      when /\ADelayed for/i
        yield("greylisting-pass")
      when /Sender is SPF-compliant/i, /Sender passed SPF test/i
        yield("spf-pass")
      end
    end

    def parse_x_virus_status(value)
      case value
      when /\AInfected/i
        yield("virus")
      end
    end
  end

  class MiltersGraphGenerator
    attr_reader :last_update_time
    def initialize(output_directory, update_time)
      @output_directory = output_directory
      @update_time = update_time
      @last_update_time = nil
    end

    def prepare
      @generators = []
      last_update_times = []
      glob = File.join(@output_directory, "milter.{status,report}.*.rrd")
      Dir.glob(glob).each do |rrd|
        last_update_times << RRD.last_update_time(rrd)
      end
      @last_update_time = last_update_times.min
    end

    def feed(time_stamp, content)
      case content
      when /\A\[milter\]\[end\]\[(.+?)\]\[(.+?)\]\[(.+?)\]\((.+?)\): (.+)\z/
        state = $1
        status = $2
        elapsed = $3
        id = $4
        name = $5
        unless @generators.find {|generator| generator.name == name}
          [MilterStatusGraphGenerator,
           MilterReportGraphGenerator].each do |generator_class|
            generator = generator_class.new(name,
                                            @output_directory,
                                            @update_time)
            generator.prepare
            @generators << generator
          end
        end
      end

      @generators.each do |generator|
        generator.feed(time_stamp, content)
      end
    end

    def flush
      @generators.each do |generator|
        generator.flush
      end
    end

    def output_graphs(range_class, options={})
      @generators.collect do |generator|
        generator.output_graph(range_class, options)
      end.compact
    end
  end

  class MilterStatusGraphGenerator < MilterManagerStatusGraphGenerator
    attr_reader :name
    def initialize(name, output_directory, update_time)
      super(output_directory, update_time)
      @name = name
      @title = "milter: status: #{@name}"
      @items << "stop"
      @old_base_rrd_file_names = [
        "milter-log.milter.#{@name}.rrd",
        "milter.#{@name}.rrd",
      ]
    end

    def rrd_file
      build_path("milter.status.#{@name}.rrd")
    end

    def graph_name(tag)
      build_path("milter.status.#{@name}.#{tag}.png")
    end

    private
    def find_data(content)
      case content
      when /\A\[milter\]\[end\]\[(.+?)\]\[(.+?)\]\[(.+?)\]\((.+?)\): (.+)\z/
        state = $1
        status = $2
        elapsed = $3
        id = $4
        name = $5
        yield(status) if name == @name
      end
    end

    def graph_entries
      entries = super
      entries << ["STACK", "stop", "#99ffff", "Stop"]
      entries
    end
  end

  class MilterReportGraphGenerator < MilterManagerReportGraphGenerator
    attr_reader :name
    def initialize(name, output_directory, update_time)
      super(output_directory, update_time)
      @name = name
      @title = "milter: report: #{@name}"
      @old_base_rrd_file_names = []
    end

    def rrd_file
      build_path("milter.report.#{@name}.rrd")
    end

    def graph_name(tag)
      build_path("milter.report.#{@name}.#{tag}.png")
    end

    private
    def report_key(header_name, header_value, milter_name, &block)
      return if @name != milter_name
      super(header_name, header_value, milter_name, &block)
    end
  end

  class HTMLGenerator
    include ERB::Util

    def initialize(graph_info)
      @graph_info = graph_info
    end

    def generate
      header + index + graphs + footer
    end

    private
    def header
      <<-EOH
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
      "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="content-type" content="text/html;charset=UTF-8" />
    <meta http-equiv="Refresh" content="300" />
    <meta http-equiv="Pragma" content="no-cache" />
    <style>
ul.index li.range
{
  display: block;
  float: left;
  margin-bottom: 1em;
  margin-right: 1em;
}

h2
{
  clear: both;
}
    </style>
    <title>milter-manager statistics</title>
  </head>

  <body>
    <h1>milter-manager statistics</h1>
EOH
    end

    def index
      result = "<ul class=\"index\">\n"
      @graph_info.each do |label, graphs|
        next if graphs.empty?
        id = label_to_id(label)
        result << %Q[  <li class="range"><a href="\##{h(id)}">#{h(label)}</a>\n]
        result << %Q[    <ul class="graph-index">\n]
        graphs.each do |file_name, title|
          graph_id = graph_title_to_id(label, title)
          result << %Q[      <li><a href="\##{h(graph_id)}">#{h(title)}</a>\n]
        end
        result << %Q[    </ul>\n]
        result << %Q[  </li>\n]
      end
      result << "</ul>\n"
      result
    end

    def graphs
      result = ""
      @graph_info.each do |label, graphs|
        next if graphs.empty?
        id = label_to_id(label)
        result << %Q[<h2 id=\"#{h(id)}\">#{h(label)}</h2>\n]
        graphs.each do |file_name, title|
          graph_id = graph_title_to_id(label, title)
          result << %Q[  <p id="#{graph_id}">\n]
          result << %Q[    <img src="#{h(File.basename(file_name))}" />\n]
          result << %Q[  </p>\n]
        end
        result << "\n"
      end
      result
    end

    def footer
      <<-EOF
  </body>
</html>
EOF
    end

    def label_to_id(label)
      normalize_value(label)
    end

    def graph_title_to_id(label, title)
      [normalize_value(label), normalize_value(title)].join("-")
    end

    def normalize_value(value)
      value.downcase.gsub(/[ :]+/, '-')
    end
  end

  attr_accessor :log, :output_directory, :now
  def initialize
    @log = ARGF
    @update_db = true
    @output_directory = "."
    @output_graphs = []
  end

  def parse_options(argv)
    opts = OptionParser.new do |opts|
      opts.on("--log=LOG_FILE",
              "The log file name in which is stored Milter log",
              "(STDIN)") do |log|
        @log = File.open(log)
      end

      opts.on("--output-directory=DIRECTORY",
              "Output graph, HTML and graph data to DIRECTORY",
              "(#{@output_directory})") do |directory|
        @output_directory = directory
        unless File.exist?(@output_directory)
          FileUtils.mkdir_p(@output_directory)
        end
      end

      opts.on("--[no-]update-db",
              "Update RRD database with log file",
              "(#{@update_db})") do |boolean|
        @update_db = boolean
      end
    end
    opts.parse!(argv)
  end

  def prepare
    all_listeners.each do |listener|
      listener.prepare
    end
  end

  def update
    return unless @update_db

    listeners = all_listeners
    last_update_times = []
    listeners.each do |listener|
      last_update_times << (listener.last_update_time || Time.at(0))
    end
    last_update_time = last_update_times.max || Time.at(0)

    year = now.year
    @log.each_line do |line|
      case line
      when /\A(\w{3}) +(\d+) (\d+):(\d+):(\d+) [\w\-]+ ([\w\-]+)\[\d+\]: /
        month_name = $1
        day = $2
        hour = $3
        minute = $4
        second = $5
        name = $6
        content = $POSTMATCH
        next unless name == "milter-manager"
        if /\A\[statistics\] / =~ remove_message_id(content)
          content = $POSTMATCH.chomp
        else
          next
        end
        month = Time::RFC2822_MONTH_NAME.index(month_name)
        next if month.nil?
        time_stamp = Time.local(year, month + 1, day.to_i,
                                hour.to_i, minute.to_i, second.to_i)
        next if time_stamp < last_update_time
        listeners.each do |listener|
          listener.feed(time_stamp, content)
        end
      else
      end
    end

    listeners.each do |listener|
      listener.flush
    end
  end

  def remove_message_id(log)
    log.sub(/\A\[ID \d+ \w+\.\w+\] /, '')
  end

  def all_listeners
    [sessions, milter_manager_status, milter_manager_report, milters]
  end

  def output
    output_all_graph
    output_html
  end

  private
  def output_graph(range, label, options={})
    output_graph_info = []
    [milter_manager_status, milter_manager_report].each do |generator|
      info = generator.output_graph(range, options)
      output_graph_info << info if info
    end
    output_graph_info.concat(milters.output_graphs(range, options))
    @output_graphs << [label, output_graph_info]
  end

  def output_all_graph
    output_graph(GraphData::DayRange, "Last Day")
    output_graph(GraphData::WeekRange, "Last Week")
    output_graph(GraphData::MonthRange, "Last Month")
    output_graph(GraphData::YearRange, "Last Year")
  end

  def output_html
    File.open(File.join(@output_directory, "index.html"), "w") do |html|
      generator = HTMLGenerator.new(@output_graphs)
      html.print(generator.generate)
    end
  end

  def now
    @now ||= Time.now.utc
  end

  def sessions
    @sessions ||= SessionGraphGenerator.new(@output_directory, now)
  end

  def milter_manager_status
    @milter_manager_status ||=
      MilterManagerStatusGraphGenerator.new(@output_directory, now)
  end

  def milter_manager_report
    @milter_manager_report ||=
      MilterManagerReportGraphGenerator.new(@output_directory, now)
  end

  def milters
    @milters ||= MiltersGraphGenerator.new(@output_directory, now)
  end
end

if __FILE__ == $0
  milter_log_analyzer = MilterManagerLogAnalyzer.new
  milter_log_analyzer.parse_options(ARGV)
  milter_log_analyzer.prepare
  milter_log_analyzer.update
  milter_log_analyzer.output
end

# vi:ts=2:nowrap:ai:expandtab:sw=2
