# encoding: UTF-8
#-- vim:sw=2:et
#++
#
# :title: rbot core

require 'thread'

require 'etc'
require 'date'
require 'fileutils'

require 'pp'

unless Kernel.respond_to? :pretty_inspect
  def pretty_inspect
    PP.pp(self, '')
  end
  public :pretty_inspect
end

class Exception
  def pretty_print(q)
    q.group(1, "#<%s: %s" % [self.class, self.message], ">") {
      if self.backtrace and not self.backtrace.empty?
        q.text "\n"
        q.seplist(self.backtrace, lambda { q.text "\n" } ) { |l| q.text l }
      end
    }
  end
end

class ServerError < RuntimeError
end

# The following global is used for the improved signal handling.
$interrupted = 0

# these first
require 'rbot/logger'
require 'rbot/rbotconfig'
require 'rbot/load-gettext'
require 'rbot/config'
require 'rbot/irc'
require 'rbot/rfc2812'
require 'rbot/ircsocket'
require 'rbot/botuser'
require 'rbot/timer'
require 'rbot/registry'
require 'rbot/plugins'
require 'rbot/message'
require 'rbot/language'
require 'rbot/httputil'

module Irc

# Main bot class, which manages the various components, receives messages,
# handles them or passes them to plugins, and contains core functionality.
class Bot
  COPYRIGHT_NOTICE = "(c) Giuseppe Bilotta and the rbot development team"
  SOURCE_URL = "https://ruby-rbot.org"
  # the bot's Auth data
  attr_reader :auth

  # the bot's Config data
  attr_reader :config

  # the botclass for this bot (determines configdir among other things)
  attr_reader :botclass

  # used to perform actions periodically (saves configuration once per minute
  # by default)
  attr_reader :timer

  # synchronize with this mutex while touching permanent data files:
  # saving, flushing, cleaning up ...
  attr_reader :save_mutex

  # bot's Language data
  attr_reader :lang

  # bot's irc socket
  # TODO multiserver
  attr_reader :socket

  # bot's plugins. This is an instance of class Plugins
  attr_reader :plugins

  # bot's httputil helper object, for fetching resources via http. Sets up
  # proxies etc as defined by the bot configuration/environment
  attr_accessor :httputil

  # mechanize agent factory
  attr_accessor :agent

  # loads and opens new registry databases, used by the plugins
  attr_accessor :registry_factory

  # web service
  attr_accessor :webservice

  # server we are connected to
  # TODO multiserver
  def server
    @client.server
  end

  # bot User in the client/server connection
  # TODO multiserver
  def myself
    @client.user
  end

  # bot nick in the client/server connection
  def nick
    myself.nick
  end

  # bot channels in the client/server connection
  def channels
    myself.channels
  end

  # nick wanted by the bot. This defaults to the irc.nick config value,
  # but may be overridden by a manual !nick command
  def wanted_nick
    @wanted_nick || config['irc.nick']
  end

  # set the nick wanted by the bot
  def wanted_nick=(wn)
    if wn.nil? or wn.to_s.downcase == config['irc.nick'].downcase
      @wanted_nick = nil
    else
      @wanted_nick = wn.to_s.dup
    end
  end


  # bot inspection
  # TODO multiserver
  def inspect
    ret = self.to_s[0..-2]
    ret << ' version=' << $version.inspect
    ret << ' botclass=' << botclass.inspect
    ret << ' lang="' << lang.language
    if defined?(GetText)
      ret << '/' << locale
    end
    ret << '"'
    ret << ' nick=' << nick.inspect
    ret << ' server='
    if server
      ret << (server.to_s + (socket ?
        ' [' << socket.server_uri.to_s << ']' : '')).inspect
      unless server.channels.empty?
        ret << " channels="
        ret << server.channels.map { |c|
          "%s%s" % [c.modes_of(nick).map { |m|
            server.prefix_for_mode(m)
          }, c.name]
        }.inspect
      end
    else
      ret << '(none)'
    end
    ret << ' plugins=' << plugins.inspect
    ret << ">"
  end


  # create a new Bot with botclass +botclass+
  def initialize(botclass, params = {})
    # Config for the core bot
    # TODO should we split socket stuff into ircsocket, etc?
    Config.register Config::ArrayValue.new('server.list',
      :default => ['irc://localhost'], :wizard => true,
      :requires_restart => true,
      :desc => "List of irc servers rbot should try to connect to. Use comma to separate values. Servers are in format 'server.doma.in:port'. If port is not specified, default value (6667) is used.")
    Config.register Config::BooleanValue.new('server.ssl',
      :default => false, :requires_restart => true, :wizard => true,
      :desc => "Use SSL to connect to this server?")
    Config.register Config::BooleanValue.new('server.ssl_verify',
      :default => false, :requires_restart => true,
      :desc => "Verify the SSL connection?",
      :wizard => true)
    Config.register Config::StringValue.new('server.ssl_ca_file',
      :default => default_ssl_ca_file, :requires_restart => true,
      :desc => "The CA file used to verify the SSL connection.",
      :wizard => true)
    Config.register Config::StringValue.new('server.ssl_ca_path',
      :default => default_ssl_ca_path, :requires_restart => true,
      :desc => "Alternativly a directory that includes CA PEM files used to verify the SSL connection.",
      :wizard => true)
    Config.register Config::StringValue.new('server.password',
      :default => false, :requires_restart => true,
      :desc => "Password for connecting to this server (if required)",
      :wizard => true)
    Config.register Config::StringValue.new('server.bindhost',
      :default => false, :requires_restart => true,
      :desc => "Specific local host or IP for the bot to bind to (if required)",
      :wizard => true)
    Config.register Config::IntegerValue.new('server.reconnect_wait',
      :default => 5, :validate => Proc.new{|v| v >= 0},
      :desc => "Seconds to wait before attempting to reconnect, on disconnect")
    Config.register Config::IntegerValue.new('server.ping_timeout',
      :default => 30, :validate => Proc.new{|v| v >= 0},
      :desc => "reconnect if server doesn't respond to PING within this many seconds (set to 0 to disable)")
    Config.register Config::ArrayValue.new('server.nocolor_modes',
      :default => ['c'], :wizard => false,
      :requires_restart => false,
      :desc => "List of channel modes that require messages to be without colors")

    Config.register Config::StringValue.new('irc.nick', :default => "rbot",
      :desc => "IRC nickname the bot should attempt to use", :wizard => true,
      :on_change => Proc.new{|bot, v| bot.sendq "NICK #{v}" })
    Config.register Config::StringValue.new('irc.name',
      :default => "Ruby bot", :requires_restart => true,
      :desc => "IRC realname the bot should use")
    Config.register Config::BooleanValue.new('irc.name_copyright',
      :default => true, :requires_restart => true,
      :desc => "Append copyright notice to bot realname? (please don't disable unless it's really necessary)")
    Config.register Config::StringValue.new('irc.user', :default => "rbot",
      :requires_restart => true,
      :desc => "local user the bot should appear to be", :wizard => true)
    Config.register Config::ArrayValue.new('irc.join_channels',
      :default => [], :wizard => true,
      :desc => "What channels the bot should always join at startup. List multiple channels using commas to separate. If a channel requires a password, use a space after the channel name. e.g: '#chan1, #chan2, #secretchan secritpass, #chan3'")
    Config.register Config::ArrayValue.new('irc.ignore_users',
      :default => [],
      :desc => "Which users to ignore input from. This is mainly to avoid bot-wars triggered by creative people")
    Config.register Config::ArrayValue.new('irc.ignore_channels',
      :default => [],
      :desc => "Which channels to ignore input in. This is mainly to turn the bot into a logbot that doesn't interact with users in any way (in the specified channels)")

    Config.register Config::IntegerValue.new('core.save_every',
      :default => 60, :validate => Proc.new{|v| v >= 0},
      :on_change => Proc.new { |bot, v|
        if @save_timer
          if v > 0
            @timer.reschedule(@save_timer, v)
            @timer.unblock(@save_timer)
          else
            @timer.block(@save_timer)
          end
        else
          if v > 0
            @save_timer = @timer.add(v) { bot.save }
          end
          # Nothing to do when v == 0
        end
      },
      :desc => "How often the bot should persist all configuration to disk (in case of a server crash, for example)")

    Config.register Config::BooleanValue.new('core.run_as_daemon',
      :default => false, :requires_restart => true,
      :desc => "Should the bot run as a daemon?")

    Config.register Config::StringValue.new('log.file',
      :default => false, :requires_restart => true,
      :desc => "Name of the logfile to which console messages will be redirected when the bot is run as a daemon")
    Config.register Config::IntegerValue.new('log.level',
      :default => 1, :requires_restart => false,
      :validate => Proc.new { |v| (0..5).include?(v) },
      :on_change => Proc.new { |bot, v|
        LoggerManager.instance.set_level(v)
      },
      :desc => "The minimum logging level (0=DEBUG,1=INFO,2=WARN,3=ERROR,4=FATAL) for console messages")
    Config.register Config::IntegerValue.new('log.keep',
      :default => 1, :requires_restart => true,
      :validate => Proc.new { |v| v >= 0 },
      :desc => "How many old console messages logfiles to keep")
    Config.register Config::IntegerValue.new('log.max_size',
      :default => 10, :requires_restart => true,
      :validate => Proc.new { |v| v > 0 },
      :desc => "Maximum console messages logfile size (in megabytes)")

    Config.register Config::ArrayValue.new('plugins.path',
      :wizard => true, :default => ['(default)', '(default)/games', '(default)/contrib'],
      :requires_restart => false,
      :on_change => Proc.new { |bot, v| bot.setup_plugins_path },
      :desc => "Where the bot should look for plugins. List multiple directories using commas to separate. Use '(default)' for default prepackaged plugins collection, '(default)/contrib' for prepackaged unsupported plugins collection")

    Config.register Config::EnumValue.new('send.newlines',
      :values => ['split', 'join'], :default => 'split',
      :on_change => Proc.new { |bot, v|
        bot.set_default_send_options :newlines => v.to_sym
      },
      :desc => "When set to split, messages with embedded newlines will be sent as separate lines. When set to join, newlines will be replaced by the value of join_with")
    Config.register Config::StringValue.new('send.join_with',
      :default => ' ',
      :on_change => Proc.new { |bot, v|
        bot.set_default_send_options :join_with => v.dup
      },
      :desc => "String used to replace newlines when send.newlines is set to join")
    Config.register Config::IntegerValue.new('send.max_lines',
      :default => 5,
      :validate => Proc.new { |v| v >= 0 },
      :on_change => Proc.new { |bot, v|
        bot.set_default_send_options :max_lines => v
      },
      :desc => "Maximum number of IRC lines to send for each message (set to 0 for no limit)")
    Config.register Config::EnumValue.new('send.overlong',
      :values => ['split', 'truncate'], :default => 'split',
      :on_change => Proc.new { |bot, v|
        bot.set_default_send_options :overlong => v.to_sym
      },
      :desc => "When set to split, messages which are too long to fit in a single IRC line are split into multiple lines. When set to truncate, long messages are truncated to fit the IRC line length")
    Config.register Config::StringValue.new('send.split_at',
      :default => '\s+',
      :on_change => Proc.new { |bot, v|
        bot.set_default_send_options :split_at => Regexp.new(v)
      },
      :desc => "A regular expression that should match the split points for overlong messages (see send.overlong)")
    Config.register Config::BooleanValue.new('send.purge_split',
      :default => true,
      :on_change => Proc.new { |bot, v|
        bot.set_default_send_options :purge_split => v
      },
      :desc => "Set to true if the splitting boundary (set in send.split_at) should be removed when splitting overlong messages (see send.overlong)")
    Config.register Config::StringValue.new('send.truncate_text',
      :default => "#{Reverse}...#{Reverse}",
      :on_change => Proc.new { |bot, v|
        bot.set_default_send_options :truncate_text => v.dup
      },
      :desc => "When truncating overlong messages (see send.overlong) or when sending too many lines per message (see send.max_lines) replace the end of the last line with this text")
    Config.register Config::IntegerValue.new('send.penalty_pct',
      :default => 100,
      :validate => Proc.new { |v| v >= 0 },
      :on_change => Proc.new { |bot, v|
        bot.socket.penalty_pct = v
      },
      :desc => "Percentage of IRC penalty to consider when sending messages to prevent being disconnected for excess flood. Set to 0 to disable penalty control.")
    Config.register Config::StringValue.new('core.db',
      :default => default_db, :store_default => true,
      :wizard => true,
      :validate => Proc.new { |v| Registry::formats.include? v },
      :requires_restart => true,
      :desc => "DB adaptor to use for storing the plugin data/registries. Options: " + Registry::formats.join(', '))

    @argv = params[:argv]
    @run_dir = params[:run_dir] || Dir.pwd

    unless FileTest.directory? Config::coredir
      error "core directory '#{Config::coredir}' not found, did you setup.rb?"
      exit 2
    end

    unless FileTest.directory? Config::datadir
      error "data directory '#{Config::datadir}' not found, did you setup.rb?"
      exit 2
    end

    unless botclass and not botclass.empty?
      # We want to find a sensible default.
      # * On POSIX systems we prefer ~/.rbot for the effective uid of the process
      # * On Windows (at least the NT versions) we want to put our stuff in the
      #   Application Data folder.
      # We don't use any particular O/S detection magic, exploiting the fact that
      # Etc.getpwuid is nil on Windows
      if Etc.getpwuid(Process::Sys.geteuid)
        botclass = Etc.getpwuid(Process::Sys.geteuid)[:dir].dup
      else
        if ENV.has_key?('APPDATA')
          botclass = ENV['APPDATA'].dup
          botclass.gsub!("\\","/")
        end
      end
      botclass = File.join(botclass, ".rbot")
    end
    botclass = File.expand_path(botclass)
    @botclass = botclass.gsub(/\/$/, "")

    repopulate_botclass_directory

    # Time at which the last PING was sent
    @last_ping = nil
    # Time at which the last line was RECV'd from the server
    @last_rec = nil

    @startup_time = Time.new

    begin
      @config = Config.manager
      @config.bot_associate(self)
    rescue Exception => e
      fatal e
      exit 2
    end

    if @config['core.run_as_daemon']
      $daemonize = true
    end

    @registry_factory = Registry.new @config['core.db']
    @registry_factory.migrate_registry_folder(path)

    @logfile = @config['log.file']
    if @logfile.class != String || @logfile.empty?
      logfname =  File.basename(botclass).gsub(/^\.+/,'')
      logfname << ".log"
      @logfile = File.join(botclass, logfname)
      debug "Using `#{@logfile}' as debug log"
    end

    LoggerManager.instance.flush

    # See http://blog.humlab.umu.se/samuel/archives/000107.html
    # for the backgrounding code
    if $daemonize
      begin
        exit if fork
        Process.setsid
        exit if fork
      rescue NotImplementedError
        warning "Could not background, fork not supported"
      rescue SystemExit
        exit 0
      rescue Exception => e
        warning "Could not background. #{e.pretty_inspect}"
      end
      Dir.chdir botclass
      # File.umask 0000                # Ensure sensible umask. Adjust as needed.
    end

    # setup logger based on bot configuration, if not set from the command line
    loglevel_set = $opts.has_key?('debug') or $opts.has_key?('loglevel')
    LoggerManager.instance.set_level(@config['log.level']) unless loglevel_set

    # Set the logfile
    LoggerManager.instance.set_logfile(@logfile, @config['log.keep'], @config['log.max_size'])

    if $daemonize
      log "Redirecting standard input/output/error, console logger disabled"
      LoggerManager.instance.flush
      LoggerManager.instance.disable_console_logger

      [$stdin, $stdout, $stderr].each do |fd|
        begin
          fd.reopen "/dev/null"
        rescue Errno::ENOENT
          # On Windows, there's not such thing as /dev/null
          fd.reopen "NUL"
        end
      end

      def $stdout.write(*args)
        str = args.map { |s| s.to_s }.join("")
        log str, 2
        return str.bytesize
      end
      def $stderr.write(*args)
        str = args.map { |s| s.to_s }.join("")
        if str.to_s.match(/:\d+: warning:/)
          warning str, 2
        else
          error str, 2
        end
        return str.bytesize
      end

      LoggerManager.instance.log_session_start
    end

    File.open($opts['pidfile'] || File.join(@botclass, 'rbot.pid'), 'w') do |pf|
      pf << "#{$$}\n"
    end

    @timer = Timer.new
    @save_mutex = Mutex.new
    if @config['core.save_every'] > 0
      @save_timer = @timer.add(@config['core.save_every']) { save }
    else
      @save_timer = nil
    end
    @quit_mutex = Mutex.new

    @plugins = nil
    @lang = Language.new(self, @config['core.language'])
    @httputil = Utils::HttpUtil.new(self)

    begin
      @auth = Auth::manager
      @auth.bot_associate(self)
      # @auth.load("#{botclass}/botusers.yaml")
    rescue Exception => e
      fatal e
      exit 2
    end
    @auth.everyone.set_default_permission("*", true)
    @auth.botowner.password= @config['auth.password']

    @plugins = Plugins::manager
    @plugins.bot_associate(self)
    setup_plugins_path()

    if @config['server.name']
        debug "upgrading configuration (server.name => server.list)"
        srv_uri = 'irc://' + @config['server.name']
        srv_uri += ":#{@config['server.port']}" if @config['server.port']
        @config.items['server.list'.to_sym].set_string(srv_uri)
        @config.delete('server.name'.to_sym)
        @config.delete('server.port'.to_sym)
        debug "server.list is now #{@config['server.list'].inspect}"
    end

    @socket = Irc::Socket.new(@config['server.list'], @config['server.bindhost'], 
                              :ssl => @config['server.ssl'],
                              :ssl_verify => @config['server.ssl_verify'],
                              :ssl_ca_file => @config['server.ssl_ca_file'],
                              :ssl_ca_path => @config['server.ssl_ca_path'],
                              :penalty_pct => @config['send.penalty_pct'])
    @client = Client.new

    @plugins.scan

    # Channels where we are quiet
    # Array of channels names where the bot should be quiet
    # '*' means all channels
    #
    @quiet = Set.new
    # but we always speak here
    @not_quiet = Set.new

    # the nick we want, if it's different from the irc.nick config value
    # (e.g. as set by a !nick command)
    @wanted_nick = nil

    @client[:welcome] = proc {|data|
      m = WelcomeMessage.new(self, server, data[:source], data[:target], data[:message])

      @plugins.delegate("welcome", m)
      @plugins.delegate("connect")
    }

    # TODO the next two @client should go into rfc2812.rb, probably
    # Since capabs are two-steps processes, server.supports[:capab]
    # should be a three-state: nil, [], [....]
    asked_for = { :"identify-msg" => false }
    @client[:isupport] = proc { |data|
      if server.supports[:capab] and !asked_for[:"identify-msg"]
        sendq "CAPAB IDENTIFY-MSG"
        asked_for[:"identify-msg"] = true
      end
    }
    @client[:datastr] = proc { |data|
      if data[:text] == "IDENTIFY-MSG"
        server.capabilities[:"identify-msg"] = true
      else
        debug "Not handling RPL_DATASTR #{data[:servermessage]}"
      end
    }

    @client[:privmsg] = proc { |data|
      m = PrivMessage.new(self, server, data[:source], data[:target], data[:message], :handle_id => true)
      # debug "Message source is #{data[:source].inspect}"
      # debug "Message target is #{data[:target].inspect}"
      # debug "Bot is #{myself.inspect}"

      @config['irc.ignore_channels'].each { |channel|
        if m.target.downcase == channel.downcase
          m.ignored = true
          break
        end
      }
      @config['irc.ignore_users'].each { |mask|
        if m.source.matches?(server.new_netmask(mask))
          m.ignored = true
          break
        end
      } unless m.ignored

      @plugins.irc_delegate('privmsg', m)
    }
    @client[:notice] = proc { |data|
      message = NoticeMessage.new(self, server, data[:source], data[:target], data[:message], :handle_id => true)
      # pass it off to plugins that want to hear everything
      @plugins.irc_delegate "notice", message
    }
    @client[:motd] = proc { |data|
      m = MotdMessage.new(self, server, data[:source], data[:target], data[:motd])
      @plugins.delegate "motd", m
    }
    @client[:nicktaken] = proc { |data|
      new = "#{data[:nick]}_"
      nickchg new
      # If we're setting our nick at connection because our choice was taken,
      # we have to fix our nick manually, because there will be no NICK message
      # to inform us that our nick has been changed.
      if data[:target] == '*'
        debug "setting my connection nick to #{new}"
        @client.user.nick = new
      end
      @plugins.delegate "nicktaken", data[:nick]
    }
    @client[:badnick] = proc {|data|
      warning "bad nick (#{data[:nick]})"
    }
    @client[:ping] = proc {|data|
      sendq "PONG #{data[:pingid]}"
    }
    @client[:pong] = proc {|data|
      @last_ping = nil
    }
    @client[:nick] = proc {|data|
      # debug "Message source is #{data[:source].inspect}"
      # debug "Bot is #{myself.inspect}"
      source = data[:source]
      old = data[:oldnick]
      new = data[:newnick]
      m = NickMessage.new(self, server, source, old, new)
      m.is_on = data[:is_on]
      if source == myself
        debug "my nick is now #{new}"
      end
      @plugins.irc_delegate("nick", m)
    }
    @client[:quit] = proc {|data|
      source = data[:source]
      message = data[:message]
      m = QuitMessage.new(self, server, source, source, message)
      m.was_on = data[:was_on]
      @plugins.irc_delegate("quit", m)
    }
    @client[:mode] = proc {|data|
      m = ModeChangeMessage.new(self, server, data[:source], data[:target], data[:modestring])
      m.modes = data[:modes]
      @plugins.delegate "modechange", m
    }
    @client[:whois] = proc {|data|
      source = data[:source]
      target = server.get_user(data[:whois][:nick])
      m = WhoisMessage.new(self, server, source, target, data[:whois])
      @plugins.delegate "whois", m
    }
    @client[:list] = proc {|data|
      source = data[:source]
      m = ListMessage.new(self, server, source, source, data[:list])
      @plugins.delegate "irclist", m
    }
    @client[:join] = proc {|data|
      m = JoinMessage.new(self, server, data[:source], data[:channel], data[:message])
      sendq("MODE #{data[:channel]}", nil, 0) if m.address?
      @plugins.irc_delegate("join", m)
      sendq("WHO #{data[:channel]}", data[:channel], 2) if m.address?
    }
    @client[:part] = proc {|data|
      m = PartMessage.new(self, server, data[:source], data[:channel], data[:message])
      @plugins.irc_delegate("part", m)
    }
    @client[:kick] = proc {|data|
      m = KickMessage.new(self, server, data[:source], data[:target], data[:channel],data[:message])
      @plugins.irc_delegate("kick", m)
    }
    @client[:invite] = proc {|data|
      m = InviteMessage.new(self, server, data[:source], data[:target], data[:channel])
      @plugins.irc_delegate("invite", m)
    }
    @client[:changetopic] = proc {|data|
      m = TopicMessage.new(self, server, data[:source], data[:channel], data[:topic])
      m.info_or_set = :set
      @plugins.irc_delegate("topic", m)
    }
    # @client[:topic] = proc { |data|
    #   irclog "@ Topic is \"#{data[:topic]}\"", data[:channel]
    # }
    @client[:topicinfo] = proc { |data|
      channel = data[:channel]
      topic = channel.topic
      m = TopicMessage.new(self, server, data[:source], channel, topic)
      m.info_or_set = :info
      @plugins.irc_delegate("topic", m)
    }
    @client[:names] = proc { |data|
      m = NamesMessage.new(self, server, server, data[:channel])
      m.users = data[:users]
      @plugins.delegate "names", m
    }
    @client[:banlist] = proc { |data|
      m = BanlistMessage.new(self, server, server, data[:channel])
      m.bans = data[:bans]
      @plugins.delegate "banlist", m
    }
    @client[:nosuchtarget] = proc { |data|
      m = NoSuchTargetMessage.new(self, server, server, data[:target], data[:message])
      @plugins.delegate "nosuchtarget", m
    }
    @client[:error] = proc { |data|
      raise ServerError, data[:message]
    }
    @client[:unknown] = proc { |data|
      #debug "UNKNOWN: #{data[:serverstring]}"
      m = UnknownMessage.new(self, server, server, nil, data[:serverstring])
      @plugins.delegate "unknown_message", m
    }

    set_default_send_options :newlines => @config['send.newlines'].to_sym,
      :join_with => @config['send.join_with'].dup,
      :max_lines => @config['send.max_lines'],
      :overlong => @config['send.overlong'].to_sym,
      :split_at => Regexp.new(@config['send.split_at']),
      :purge_split => @config['send.purge_split'],
      :truncate_text => @config['send.truncate_text'].dup

    trap_signals
  end

  # Determine (if possible) a valid path to a CA certificate bundle. 
  def default_ssl_ca_file
    [ '/etc/ssl/certs/ca-certificates.crt', # Ubuntu/Debian
      '/etc/ssl/certs/ca-bundle.crt', # Amazon Linux
      '/etc/ssl/ca-bundle.pem', # OpenSUSE
      '/etc/pki/tls/certs/ca-bundle.crt' # Fedora/RHEL
    ].find do |file|
      File.readable? file
    end
  end

  def default_ssl_ca_path
    file = default_ssl_ca_file
    File.dirname file if file
  end

  # Determine if tokyocabinet is installed, if it is use it as a default.
  def default_db
    begin
      require 'tokyocabinet'
      return 'tc'
    rescue LoadError
      return 'dbm'
    end
  end

  def repopulate_botclass_directory
    template_dir = File.join Config::datadir, 'templates'
    if FileTest.directory? @botclass
      # compare the templates dir with the current botclass dir, filling up the
      # latter with any missing file. Sadly, FileUtils.cp_r doesn't have an
      # :update option, so we have to do it manually.
      # Note that we use the */** pattern because we don't want to match
      # keywords.rbot, which gets deleted on load and would therefore be missing
      # always
      missing = Dir.chdir(template_dir) { Dir.glob('*/**') } - Dir.chdir(@botclass) { Dir.glob('*/**') }
      missing.map do |f|
        dest = File.join(@botclass, f)
        FileUtils.mkdir_p(File.dirname(dest))
        FileUtils.cp File.join(template_dir, f), dest
      end
    else
      log "no #{@botclass} directory found, creating from templates..."
      if FileTest.exist? @botclass
        error "file #{@botclass} exists but isn't a directory"
        exit 2
      end
      FileUtils.cp_r template_dir, @botclass
    end
  end

  # Return a path under the current botclass by joining the mentioned
  # components. The components are automatically converted to String
  def path(*components)
    File.join(@botclass, *(components.map {|c| c.to_s}))
  end

  def setup_plugins_path
    plugdir_default = File.join(Config::datadir, 'plugins')
    plugdir_local = File.join(@botclass, 'plugins')
    Dir.mkdir(plugdir_local) unless File.exist?(plugdir_local)

    @plugins.clear_botmodule_dirs
    @plugins.add_core_module_dir(File.join(Config::coredir, 'utils'))
    @plugins.add_core_module_dir(Config::coredir)
    if FileTest.directory? plugdir_local
      @plugins.add_plugin_dir(plugdir_local)
    else
      warning "local plugin location #{plugdir_local} is not a directory"
    end

    @config['plugins.path'].each do |_|
        path = _.sub(/^\(default\)/, plugdir_default)
        @plugins.add_plugin_dir(path)
    end
  end

  def set_default_send_options(opts={})
    # Default send options for NOTICE and PRIVMSG
    unless defined? @default_send_options
      @default_send_options = {
        :queue_channel => nil,      # use default queue channel
        :queue_ring => nil,         # use default queue ring
        :newlines => :split,        # or :join
        :join_with => ' ',          # by default, use a single space
        :max_lines => 0,          # maximum number of lines to send with a single command
        :overlong => :split,        # or :truncate
        # TODO an array of splitpoints would be preferrable for this option:
        :split_at => /\s+/,         # by default, split overlong lines at whitespace
        :purge_split => true,       # should the split string be removed?
        :truncate_text => "#{Reverse}...#{Reverse}"  # text to be appened when truncating
      }
    end
    @default_send_options.update opts unless opts.empty?
  end

  # checks if we should be quiet on a channel
  def quiet_on?(channel)
    ch = channel.downcase
    return (@quiet.include?('*') && !@not_quiet.include?(ch)) || @quiet.include?(ch)
  end

  def set_quiet(channel = nil)
    if channel
      ch = channel.downcase.dup
      @not_quiet.delete(ch)
      @quiet << ch
    else
      @quiet.clear
      @not_quiet.clear
      @quiet << '*'
    end
  end

  def reset_quiet(channel = nil)
    if channel
      ch = channel.downcase.dup
      @quiet.delete(ch)
      @not_quiet << ch
    else
      @quiet.clear
      @not_quiet.clear
    end
  end

  # things to do when we receive a signal
  def handle_signal(sig)
    func = case sig
           when 'SIGHUP'
             :restart
           when 'SIGUSR1'
             :reconnect
           else
             :quit
           end
    debug "received #{sig}, queueing #{func}"
    # this is not an interruption if we just need to reconnect
    $interrupted += 1 unless func == :reconnect
    self.send(func) unless @quit_mutex.locked?
    debug "interrupted #{$interrupted} times"
    if $interrupted >= 3
      debug "drastic!"
      exit 2
    end
  end

  # trap signals
  def trap_signals
    begin
      %w(SIGINT SIGTERM SIGHUP SIGUSR1).each do |sig|
        trap(sig) { Thread.new { handle_signal sig } }
      end
    rescue ArgumentError => e
      debug "failed to trap signals (#{e.pretty_inspect}): running on Windows?"
    rescue Exception => e
      debug "failed to trap signals: #{e.pretty_inspect}"
    end
  end

  # connect the bot to IRC
  def connect
    # make sure we don't have any spurious ping checks running
    # (and initialize the vars if this is the first time we connect)
    stop_server_pings
    begin
      quit if $interrupted > 0
      @socket.connect
      @last_rec = Time.now
    rescue Exception => e
      uri = @socket.server_uri || '<unknown>'
      error "failed to connect to IRC server at #{uri}"
      error e
      raise
    end
    quit if $interrupted > 0

    realname = @config['irc.name'].clone || 'Ruby bot'
    realname << ' ' + COPYRIGHT_NOTICE if @config['irc.name_copyright']

    @socket.emergency_puts "PASS " + @config['server.password'] if @config['server.password']
    @socket.emergency_puts "NICK #{@config['irc.nick']}\nUSER #{@config['irc.user']} 4 #{@socket.server_uri.host} :#{realname}"
    quit if $interrupted > 0
    myself.nick = @config['irc.nick']
    myself.user = @config['irc.user']
  end

  # disconnect the bot from IRC, if connected, and then connect (again)
  def reconnect(message=nil, too_fast=0)
    # we will wait only if @last_rec was not nil, i.e. if we were connected or
    # got disconnected by a network error
    # if someone wants to manually call disconnect() _and_ reconnect(), they
    # will have to take care of the waiting themselves
    will_wait = !!@last_rec

    if @socket.connected?
      disconnect(message)
    end

    begin
      if will_wait
        log "\n\nDisconnected\n\n"

        quit if $interrupted > 0

        log "\n\nWaiting to reconnect\n\n"
        sleep @config['server.reconnect_wait']
        if too_fast > 0
          tf = too_fast*@config['server.reconnect_wait']
          tfu = Utils.secs_to_string(tf)
          log "Will sleep for an extra #{tf}s (#{tfu})"
          sleep tf
        end
      end

      connect
    rescue SystemExit
      exit 0
    rescue Exception => e
      error e
      will_wait = true
      retry
    end
  end

  # begin event handling loop
  def mainloop
    @keep_looping = true
    while @keep_looping
      too_fast = 0
      quit_msg = nil
      valid_recv = false # did we receive anything (valid) from the server yet?
      begin
        reconnect(quit_msg, too_fast)
        quit if $interrupted > 0
        valid_recv = false
        while @socket.connected?
          quit if $interrupted > 0

          # Wait for messages and process them as they arrive. If nothing is
          # received, we call the ping_server() method that will PING the
          # server if appropriate, or raise a TimeoutError if no PONG has been
          # received in the user-chosen timeout since the last PING sent.
          if @socket.select(1)
            break unless reply = @socket.gets
            @last_rec = Time.now
            @client.process reply
            valid_recv = true
            too_fast = 0
          else
            ping_server
          end
        end

      # I despair of this. Some of my users get "connection reset by peer"
      # exceptions that ARENT SocketError's. How am I supposed to handle
      # that?
      rescue SystemExit
        @keep_looping = false
        break
      rescue Errno::ETIMEDOUT, Errno::ECONNABORTED, TimeoutError, SocketError => e
        error "network exception: #{e.pretty_inspect}"
        quit_msg = e.to_s
        too_fast += 10 if valid_recv
      rescue ServerMessageParseError => e
        # if the bot tried reconnecting too often, we can get forcefully
        # disconnected by the server, while still receiving an empty message
        # wait at least 10 minutes in this case
        if e.message.empty?
          oldtf = too_fast
          too_fast = [too_fast, 300].max
          too_fast*= 2
          log "Empty message from server, extra delay multiplier #{oldtf} -> #{too_fast}"
        end
        quit_msg = "Unparseable Server Message: #{e.message.inspect}"
        retry
      rescue ServerError => e
        quit_msg = "server ERROR: " + e.message
        debug quit_msg
        idx = e.message.index("connect too fast")
        debug "'connect too fast' @ #{idx}"
        if idx
          oldtf = too_fast
          too_fast += (idx+1)*2
          log "Reconnecting too fast, extra delay multiplier #{oldtf} -> #{too_fast}"
        end
        idx = e.message.index(/a(uto)kill/i)
        debug "'autokill' @ #{idx}"
        if idx
          # we got auto-killed. since we don't have an easy way to tell
          # if it's permanent or temporary, we just set a rather high
          # reconnection timeout
          oldtf = too_fast
          too_fast += (idx+1)*5
          log "Killed by server, extra delay multiplier #{oldtf} -> #{too_fast}"
        end
        retry
      rescue Exception => e
        error "non-net exception: #{e.pretty_inspect}"
        quit_msg = e.to_s
      rescue => e
        fatal "unexpected exception: #{e.pretty_inspect}"
        exit 2
      end
    end
  end

  # type:: message type
  # where:: message target
  # message:: message text
  # send message +message+ of type +type+ to target +where+
  # Type can be PRIVMSG, NOTICE, etc, but those you should really use the
  # relevant say() or notice() methods. This one should be used for IRCd
  # extensions you want to use in modules.
  def sendmsg(original_type, original_where, original_message, options={})

    # filter message with sendmsg filters
    ds = DataStream.new original_message.to_s.dup,
      :type => original_type, :dest => original_where,
      :options => @default_send_options.merge(options)
    filters = filter_names(:sendmsg)
    filters.each do |fname|
      debug "filtering #{ds[:text]} with sendmsg filter #{fname}"
      ds.merge! filter(self.global_filter_name(fname, :sendmsg), ds)
    end

    opts = ds[:options]
    type = ds[:type]
    where = ds[:dest]
    filtered = ds[:text]

    if defined? WebServiceUser and where.instance_of? WebServiceUser
      debug 'sendmsg to web service!'
      where.response << filtered
      return
    end

    # For starters, set up appropriate queue channels and rings
    mchan = opts[:queue_channel]
    mring = opts[:queue_ring]
    if mchan
      chan = mchan
    else
      chan = where
    end
    if mring
      ring = mring
    else
      case where
      when User
        ring = 1
      else
        ring = 2
      end
    end

    multi_line = filtered.gsub(/[\r\n]+/, "\n")

    # if target is a channel with nocolor modes, strip colours
    if where.kind_of?(Channel) and where.mode.any?(*config['server.nocolor_modes'])
      multi_line.replace BasicUserMessage.strip_formatting(multi_line)
    end

    messages = Array.new
    case opts[:newlines]
    when :join
      messages << [multi_line.gsub("\n", opts[:join_with])]
    when :split
      multi_line.each_line { |line|
        line.chomp!
        next unless(line.size > 0)
        messages << line
      }
    else
      raise "Unknown :newlines option #{opts[:newlines]} while sending #{original_message.inspect}"
    end

    # The IRC protocol requires that each raw message must be not longer
    # than 512 characters. From this length with have to subtract the EOL
    # terminators (CR+LF) and the length of ":botnick!botuser@bothost "
    # that will be prepended by the server to all of our messages.

    # The maximum raw message length we can send is therefore 512 - 2 - 2
    # minus the length of our hostmask.

    max_len = 508 - myself.fullform.size

    # On servers that support IDENTIFY-MSG, we have to subtract 1, because messages
    # will have a + or - prepended
    if server.capabilities[:"identify-msg"]
      max_len -= 1
    end

    # When splitting the message, we'll be prefixing the following string:
    # (e.g. "PRIVMSG #rbot :")
    fixed = "#{type} #{where} :"

    # And this is what's left
    left = max_len - fixed.size

    truncate = opts[:truncate_text]
    truncate = @default_send_options[:truncate_text] if truncate.size > left
    truncate = "" if truncate.size > left

    all_lines = messages.map { |line|
      if line.size < left
        line
      else
        case opts[:overlong]
        when :split
          msg = line.dup
          sub_lines = Array.new
          begin
            sub_lines << msg.slice!(0, left)
            break if msg.empty?
            lastspace = sub_lines.last.rindex(opts[:split_at])
            if lastspace
              msg.replace sub_lines.last.slice!(lastspace, sub_lines.last.size) + msg
              msg.gsub!(/^#{opts[:split_at]}/, "") if opts[:purge_split]
            end
          end until msg.empty?
          sub_lines
        when :truncate
          line.slice(0, left - truncate.size) << truncate
        else
          raise "Unknown :overlong option #{opts[:overlong]} while sending #{original_message.inspect}"
        end
      end
    }.flatten

    if opts[:max_lines] > 0 and all_lines.length > opts[:max_lines]
      lines = all_lines[0...opts[:max_lines]]
      new_last = lines.last.slice(0, left - truncate.size) << truncate
      lines.last.replace(new_last)
    else
      lines = all_lines
    end

    lines.each { |line|
      sendq "#{fixed}#{line}", chan, ring
      delegate_sent(type, where, line)
    }
  end

  # queue an arbitraty message for the server
  def sendq(message="", chan=nil, ring=0)
    # temporary
    @socket.queue(message, chan, ring)
  end

  # send a notice message to channel/nick +where+
  def notice(where, message, options={})
    return if where.kind_of?(Channel) and quiet_on?(where)
    sendmsg "NOTICE", where, message, options
  end

  # say something (PRIVMSG) to channel/nick +where+
  def say(where, message, options={})
    return if where.kind_of?(Channel) and quiet_on?(where)
    sendmsg "PRIVMSG", where, message, options
  end

  def ctcp_notice(where, command, message, options={})
    return if where.kind_of?(Channel) and quiet_on?(where)
    sendmsg "NOTICE", where, "\001#{command} #{message}\001", options
  end

  def ctcp_say(where, command, message, options={})
    return if where.kind_of?(Channel) and quiet_on?(where)
    sendmsg "PRIVMSG", where, "\001#{command} #{message}\001", options
  end

  # perform a CTCP action with message +message+ to channel/nick +where+
  def action(where, message, options={})
    ctcp_say(where, 'ACTION', message, options)
  end

  # quick way to say "okay" (or equivalent) to +where+
  def okay(where)
    say where, @lang.get("okay")
  end

  # set topic of channel +where+ to +topic+
  # can also be used to retrieve the topic of channel +where+
  # by omitting the last argument
  def topic(where, topic=nil)
    if topic.nil?
      sendq "TOPIC #{where}", where, 2
    else
      sendq "TOPIC #{where} :#{topic}", where, 2
    end
  end

  def disconnect(message=nil)
    message = @lang.get("quit") if (!message || message.empty?)
    if @socket.connected?
      begin
        debug "Clearing socket"
        @socket.clearq
        debug "Sending quit message"
        @socket.emergency_puts "QUIT :#{message}"
        debug "Logging quits"
        delegate_sent('QUIT', myself, message)
        debug "Flushing socket"
        @socket.flush
      rescue SocketError => e
        error "error while disconnecting socket: #{e.pretty_inspect}"
      end
      debug "Shutting down socket"
      @socket.shutdown
    end
    stop_server_pings
    @client.reset
  end

  # disconnect from the server and cleanup all plugins and modules
  def shutdown(message=nil)
    @quit_mutex.synchronize do
      debug "Shutting down: #{message}"
      ## No we don't restore them ... let everything run through
      # begin
      #   trap("SIGINT", "DEFAULT")
      #   trap("SIGTERM", "DEFAULT")
      #   trap("SIGHUP", "DEFAULT")
      # rescue => e
      #   debug "failed to restore signals: #{e.inspect}\nProbably running on windows?"
      # end
      debug "\tdisconnecting..."
      disconnect(message)
      debug "\tstopping timer..."
      @timer.stop
      debug "\tsaving ..."
      save
      debug "\tcleaning up ..."
      @save_mutex.synchronize do
        begin
          @plugins.cleanup
        rescue
          debug "\tignoring cleanup error: #{$!}"
        end
      end
      @httputil.cleanup
      # debug "\tstopping timers ..."
      # @timer.stop
      # debug "Closing registries"
      # @registry.close
      log "rbot quit (#{message})"
    end
  end

  # message:: optional IRC quit message
  # quit IRC, shutdown the bot
  def quit(message=nil)
    begin
      shutdown(message)
    ensure
      @keep_looping = false
    end
  end

  # totally shutdown and respawn the bot
  def restart(message=nil)
    message = _("restarting, back in %{wait}...") % {
      :wait => @config['server.reconnect_wait']
    } if (!message || message.empty?)
    shutdown(message)

    Irc::Bot::LoggerManager.instance.flush
    Irc::Bot::LoggerManager.instance.log_session_end

    sleep @config['server.reconnect_wait']
    begin
      # now we re-exec
      # Note, this fails on Windows
      debug "going to exec #{$0} #{@argv.inspect} from #{@run_dir}"
      Dir.chdir(@run_dir)
      exec($0, *@argv)
    rescue Errno::ENOENT
      exec("ruby", *(@argv.unshift $0))
    rescue Exception => e
      $interrupted += 1
      raise e
    end
  end

  # call the save method for all or the specified botmodule
  #
  # :botmodule ::
  #   optional botmodule to save
  def save(botmodule=nil)
    @save_mutex.synchronize do
      @plugins.save(botmodule)
    end
  end

  # call the rescan method for all or just the specified botmodule
  #
  # :botmodule ::
  #   instance of the botmodule to rescan
  def rescan(botmodule=nil)
    debug "\tstopping timer..."
    @timer.stop
    @save_mutex.synchronize do
      # @lang.rescan
      @plugins.rescan(botmodule)
    end
    @timer.start
  end

  # channel:: channel to join
  # key::     optional channel key if channel is +s
  # join a channel
  def join(channel, key=nil)
    if(key)
      sendq "JOIN #{channel} :#{key}", channel, 2
    else
      sendq "JOIN #{channel}", channel, 2
    end
  end

  # part a channel
  def part(channel, message="")
    sendq "PART #{channel} :#{message}", channel, 2
  end

  # attempt to change bot's nick to +name+
  def nickchg(name)
    sendq "NICK #{name}"
  end

  # changing mode
  def mode(channel, mode, target=nil)
    sendq "MODE #{channel} #{mode} #{target}", channel, 2
  end

  # asking whois
  def whois(nick, target=nil)
    sendq "WHOIS #{target} #{nick}", nil, 0
  end

  # kicking a user
  def kick(channel, user, msg)
    sendq "KICK #{channel} #{user} :#{msg}", channel, 2
  end

  # m::     message asking for help
  # topic:: optional topic help is requested for
  # respond to online help requests
  def help(topic=nil)
    topic = nil if topic == ""
    case topic
    when nil
      helpstr = _("help topics: ")
      helpstr += @plugins.helptopics
      helpstr += _(" (help <topic> for more info)")
    else
      unless(helpstr = @plugins.help(topic))
        helpstr = _("no help for topic %{topic}") % { :topic => topic }
      end
    end
    return helpstr
  end

  # returns a string describing the current status of the bot (uptime etc)
  def status
    secs_up = Time.new - @startup_time
    uptime = Utils.secs_to_string secs_up
    # return "Uptime #{uptime}, #{@plugins.length} plugins active, #{@registry.length} items stored in registry, #{@socket.lines_sent} lines sent, #{@socket.lines_received} received."
    return (_("Uptime %{up}, %{plug} plugins active, %{sent} lines sent, %{recv} received.") %
             {
               :up => uptime, :plug => @plugins.length,
               :sent => @socket.lines_sent, :recv => @socket.lines_received
             })
  end

  # We want to respond to a hung server in a timely manner. If nothing was received
  # in the user-selected timeout and we haven't PINGed the server yet, we PING
  # the server. If the PONG is not received within the user-defined timeout, we
  # assume we're in ping timeout and act accordingly.
  def ping_server
    act_timeout = @config['server.ping_timeout']
    return if act_timeout <= 0
    now = Time.now
    if @last_rec && now > @last_rec + act_timeout
      if @last_ping.nil?
        # No previous PING pending, send a new one
        sendq "PING :rbot"
        @last_ping = Time.now
      else
        diff = now - @last_ping
        if diff > act_timeout
          debug "no PONG from server in #{diff} seconds, reconnecting"
          # the actual reconnect is handled in the main loop:
          raise TimeoutError, "no PONG from server in #{diff} seconds"
        end
      end
    end
  end

  def stop_server_pings
    # cancel previous PINGs and reset time of last RECV
    @last_ping = nil
    @last_rec = nil
  end

  private

  # delegate sent messages
  def delegate_sent(type, where, message)
    args = [self, server, myself, server.user_or_channel(where.to_s), message]
    case type
      when "NOTICE"
        m = NoticeMessage.new(*args)
      when "PRIVMSG"
        m = PrivMessage.new(*args)
      when "QUIT"
        m = QuitMessage.new(*args)
        m.was_on = myself.channels
    end
    @plugins.delegate('sent', m)
  end

end

end