#!/bin/bash

# bashy
# IRC bot written using bash, bash sockets and CLI tools
# Jan Schampera <jan.schampera@web.de>

### CONFIG
BSHY_IRCSRV="irc.freenode.net"
BSHY_IRCPORT="6667"
BSHY_IRCCHAN="#bash"
BSHY_IRCUSER="bashy"
BSHY_IRCNAME="Bashy"
BSHY_IRCNICK="bashy"
BSHY_IRCMASTER="TheBonsai"
BSHY_PLUGINSDIR="/home/bonsai/devel/irc-bots/Bashy/plugins"
BSHY_PLUGINSENABLE="y"
BSHY_TRIGGERCHAR=";"
### /CONFIG

### NO CHANGES SHOULD BE NECCESARY BEYOND THIS POINT ###
### IF YOU NEED TO CHANGE SOMETHING YOU THINK IT MUST BE CONFIGURABLE, EMAIL ME ###

### INTERNALS
export BSHY_VERSION="0.1"
### /INTERNALS


### FUNCTIONS
bshy_helpscreen() {
cat <<MARK
BASHY V${BSHY_VERSION}
Usage:
--configfile|-f FILE            use configfile FILE
--version|-v                    display version
--help|-h                       display help (this)
MARK
}

bshy_debugmsg() {
local LEVEL="${1}"
local TAG="${2}"
local MESSAGE="${3}"

echo "${TAG}(${LEVEL}) - ${MESSAGE}" >&2

# levels:
# 0 - always
# 1 - general debug info
# 2 - detailed debug info
}

bshy_consoleinput() {

while :; do
    read -r CONSOLEINPUT;

    case "${CONSOLEINPUT}" in
        /*)
            echo "${CONSOLEINPUT:1}" >&6
            CONSOLEINPUT=""
            ;;
        *)
            echo "PRIVMSG ${BSHY_IRCCHAN} :${CONSOLEINPUT}" >&6
            CONSOLEINPUT=""
            ;;
    esac
done
}

export -f bshy_helpscreen bshy_debugmsg bshy_consoleinput
### /FUNCTIONS


### MAIN

# begin PARSE_CMDLINE
# interpret my commandline arguments
while [ ! -z "${1}" ]; do
    case "${1}" in
        "--configfile"|"-f")
                        BSHY_CONFIG="${2}"
                        shift 2
                        ;;
        "--help"|"-h")
                        bshy_helpscreen
                        exit 0
                        ;;
        "--version"|"-v")
			echo "${BSHY_VERSION}"
			exit 0
                        ;;
        *)
                        echo "Eh?" >&2
                        bshy_helpscreen >&2
                        exit 1
                        ;;
    esac
done
# end PARSE_CMDLINE

# begin READ_PLUGINS
if [ "${BSHY_PLUGINSDIR}" = "y" ]; then
    bshy_debugmsg 1 READ_PLUGINS "processing plugins in ${BSHY_PLUGINSDIR}"
    [ -d "${BSHY_PLUGINSENABLE}" ] || { bshy_debugmsg 0 READ_PLUGINS "${BSHY_PLUGINSDIR} not found"; exit 1; }
    for APLUGIN in ${BSHY_PLUGINSDIR}; do
        bshy_debugmsg 2 READ_PLUGINS "processing plugin ${APLUGIN}"
        source "${APLUGIN}"
    done
fi
# end READ_PLUGINS

# begin CREATE_SOCKET
# create the socket (FD 5 in and 6 out)
export BSHY_SOCKET="/dev/tcp/${BSHY_IRCSRV}/${BSHY_IRCPORT}"
bshy_debugmsg 1 CREATE_SOCKET "creating socket"
bshy_debugmsg 2 CREATE_SOCKET "attempting to create socket in ${BSHY_SOCKET}"
exec 6>${BSHY_SOCKET}
exec 5<&6
# end CREATE_SOCKET

# begin LOGIN
echo -en "NICK ${BSHY_IRCNICK}\r\n" >&6
echo -en "USER ${BSHY_IRCUSER} 0 * : ${BSHY_IRCNAME}\r\n" >&6
# end LOGIN


# start console input background process
bshy_consoleinput <&0 &
CONSINPTPID="$!"

# begin MAIN_LOOP
#set -x
while read SERVERINPUT <&5; do
    # remove the off \r's specified in RFC
    SERVERINPUT="${SERVERINPUT//$'\r'/}"

    # is it a normal server message ':ORIGIN MESSAGETYPE MESSAGE'?
    [ "${SERVERINPUT:0:1}" = ":" ] && IS_A_MESSAGE=1 || IS_A_MESSAGE=0

    # if it's a normal message, remove the leading ':'
    [ "${IS_A_MESSAGE}" = "1" ] && SERVERINPUT="${SERVERINPUT:1}"

    case "${IS_A_MESSAGE}" in
        "1")
            # parse the message line, ':' was removed before
            SRVMSG_ORIGIN="${SERVERINPUT%% *}"
            SRVMSG_COMMAND="${SERVERINPUT%% :*}"; SRVMSG_COMMAND="${SRVMSG_COMMAND#* }"
            SRVMSG_TYPE="${SRVMSG_COMMAND%% *}"
            SRVMSG_TARGET="${SRVMSG_COMMAND#* }"
            # SRVMSG_TYPE="${SERVERINPUT#* }"; SRVMSG_TYPE="${SERVERINPUT%% *}"
            SRVMSG_MESSAGE="${SERVERINPUT#* :}"
            case "${SRVMSG_TYPE}" in
                37[256])
                        # RPL_MOTD, RPL_MOTDSTART, RPL_MOTDEND
                        echo "<MOTD> ${SRVMSG_MESSAGE}"
                        ;;
                001)
                        # RPL_WELCOME
                        echo "<WELCOME> ${SRVMSG_ORIGIN} wecomes us, joining ${BSHY_IRCCHAN}"
                        echo -en "JOIN ${BSHY_IRCCHAN}\r\n" >&6
                        ;;
                00[2345])
                        : # ignored: RPL_YOURHOST, RPL_CREATED, RPL_MYINFO, RPL_BOUNCE
                        ;;
                25?)
                        : # ignored: server informational messages
                        ;;
                "353"|"366")
                        : # ignored: RPL_NAMREPLY, RPL_ENDOFNAMES
                        ;;
                33[123])
                        : # ignored: RPL_NOTOPIC, RPL_TOPIC, and 333 as in "set by X at <date>"
                        ;;
                [Jj][Oo][Ii][Nn])
                        echo "<JOIN> ${SRVMSG_ORIGIN%%!*} has joined ${SRVMSG_MESSAGE}"
                        ;;
                [Pp][Aa][Rr][Tt])
                        echo "<PART> ${SRVMSG_ORIGIN%%!*} has left ${SRVMSG_TARGET} (${SRVMSG_MESSAGE})"
                        ;;
                [Qq][Uu][Ii][Tt])
                        echo "<QUIT> ${SRVMSG_ORIGIN%%!*} has quit (${SRVMSG_MESSAGE})"
                        ;;
                [Pp][Rr][Ii][Vv][Mm][Ss][Gg])
                        echo "<MSG ${SRVMSG_ORIGIN%%!*}->${SRVMSG_TARGET}> ${SRVMSG_MESSAGE}"
                        if [ "${SRVMSG_MESSAGE:0:1}" = "${BSHY_TRIGGERCHAR:0:1}" ]; then
                            echo "<TRIGGER> triggered by ${SRVMSG_ORIGIN%%!*} in ${SRVMSG_TARGET}"
                        fi
                        ;;
                [Mm][Oo][Dd][Ee])
                        echo "<MODE> ${SRVMSG_ORIGIN%%!*} sets mode ${SRVMSG_MESSAGE} for ${SRVMSG_TARGET}"
                        ;;
                *)
                        echo "<UNKNOWN> COMPLETE LINE WAS: ${SERVERINPUT}"
                        ;;
                
            esac
            ;;
        "0")
            SRVMSG_TYPE="${SERVERINPUT%% *}"
            SRVMSG_TARGET="${SERVERINPUT#* }"; SRVMSG_TARGET="${SRVMSG_TARGET%% :*}"
            SRVMSG_MESSAGE="${SERVERINPUT##*:}"
            case "${SRVMSG_TYPE}" in
                [Nn][Oo][Tt][Ii][Cc][Ee])
                            echo "<NOTICE> ${SRVMSG_MESSAGE}"
                            ;;
                [Pp][Ii][Nn][Gg])
                            echo "<PING> PONG!"
                            echo -en "PONG :${SRVMSG_MESSAGE}\r\n" >&6
                            ;;
                [Ee][Rr][Rr][Oo][Rr])
                            echo "<ERROR> ${SRVMSG_MESSAGE}"
                            ;;
            esac
            ;;
    esac
    
done
# end MAIN_LOOP


### /MAIN