#!/usr/local/bin/ruby

    require "socket"

    # Don't allow use of "tainted" data by potentially dangerous operations
    $SAFE=1

    # The irc class, which talks to the server and holds the main event loop
    class IRC
        def initialize(server, port, nick, channel)
            @server = server
            @port = port
            @nick = nick
            @channel = channel
        end
        def send(s)
            # Send a message to the irc server and print it to the screen
            puts "--> #{s}"
            @irc.send "#{s}\n", 0
        end
        def connect()
            # Connect to the IRC server
            @irc = TCPSocket.open(@server, @port)
            send "USER rubybot didabot master :win loose"
            send "NICK #{@nick}"
            send "JOIN #{@channel}"
        end
        def evaluate(s)
            # Make sure we have a valid expression (for security reasons), and
            # evaluate it if we do, otherwise return an error message
            if s =~ /^[-+*\/\d\s\eE.()]*$/ then
                begin
                    s.untaint
                    return eval(s).to_s
                rescue Exception => detail
                    puts detail.message()
                end
            end
            return "Error"
        end
        def handle_server_input(s)
            # This isn't at all efficient, but it shows what we can do with Ruby
            case s.strip
                when /^PING :(.+)$/i
                    puts "[ Server ping ]"
                    send "PONG :#{$1}"
                when /^:(.+?)!(.+?)@(.+?)\sPRIVMSG\s.+\s:[\001]PING (.+)[\001]$/i
                    puts "[ CTCP PING from #{$1}!#{$2}@#{$3} ]"
                    send "NOTICE #{$1} :\001PING #{$4}\001"
                when /^:(.+?)!(.+?)@(.+?)\sPRIVMSG\s.+\s:[\001]VERSION[\001]$/i
                    puts "[ CTCP VERSION from #{$1}!#{$2}@#{$3} ]"
                    send "NOTICE #{$1} :\001VERSION DidaBot - version 0.1a\001"
                when /^:(.+?)!(.+?)@(.+?)\sPRIVMSG\s(.+)\s:EVAL (.+)$/i
                    puts "[ EVAL #{$5} from #{$1}!#{$2}@#{$3} ]"
                    send "PRIVMSG #{(($4==@nick)?$1:$4)} :#{evaluate($5)}"
                # when /^:([^!]+)![^@]+@[^ ]+ PRIVMSG #{@channel} :(.+)$/
                # when /^:([^!]+)![^@]+@[^ ]+ PRIVMSG #{@channel} :(!about)$/
                # when /^:dida![^@]+@[^ ]+ PRIVMSG #{@channel} :(.+)$/
                when /^:dida![^@]+@[^ ]+ PRIVMSG #{@channel} :(.+)$/
                    @rawr = $1.split(/ * /)
                    case @rawr[0]
                            when "!kick"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "KICK #{@channel} #{@rawr[1]} :#{@rawr.drop(1).join(" ")}"
                            when "!ban"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} +b #{@rawr[1]}"
                                    send "KICK #{@channel} #{@rawr[1]} :#{@rawr.drop(1).join(" ")}"
                            when "!unban"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} -b #{@rawr[1]}!*@*"
                            when "!op"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} +o #{@rawr[1]}"
                            when "!voice"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} +v #{@rawr[1]}"
                            when "!halfop"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} +h #{@rawr[1]}"
                            when "!deop"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} -o #{@rawr[1]}"
                            when "!devoice"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} -v #{@rawr[1]}"
                            when "!dehalfop"
                                    puts "Admin command: #{@rawr[0]}"
                                    send "MODE #{@channel} -h #{@rawr[1]}"
                            when "!say"
                                    puts "User command: #{@rawr[0]}"
                                    send "PRIVMSG #{@channel} :#{@rawr.drop(1).join(" ")}"
                            else
                                    puts @rawr[0]
                                    puts s
                    end
                when /^:([^!]+)![^@]+@[^ ]+ PRIVMSG #{@channel} :(!.+)$/
                    @dat = $1.split(/ * /)
                    case @dat[0]
                            when "!say"
                                    puts "User command: #{@dat[0]}"
                                    send "PRIVMSG #{@channel} :#{@dat.drop(1).join(" ")}"
                            else
                                    puts @rawr[0]
                                    puts s
                    end
                else
                    puts s
            end
        end
        def main_loop()
            # Just keep on truckin' until we disconnect
            while true
                ready = select([@irc, $stdin], nil, nil, nil)
                next if !ready
                for s in ready[0]
                    if s == $stdin then
                        return if $stdin.eof
                        s = $stdin.gets
                        send s
                    elsif s == @irc then
                        return if @irc.eof
                        s = @irc.gets
                        handle_server_input(s)
                    end
                end
            end
        end
    end

    # The main program
    # If we get an exception, then print it out and keep going (we do NOT want
    # to disconnect unexpectedly!)
    irc = IRC.new('irc.freenode.net', 6667, 'didabot', '#webdevrefinery')
    irc.connect()
    begin
        irc.main_loop()
        irc.send_message()
    rescue Interrupt
    rescue Exception => detail
        puts detail.message()
        print detail.backtrace.join("\n")
        retry
    end