#! /bin/bash
# vim: set tabstop=4 shiftwidth=4 expandtab filetype=sh:

if [[ $1 == "-d" ]]; then
    shift
    setgetty=1
else
    setgetty=
fi

if [[ $1 == "-f" ]]; then
    shift
    force=1
else
    force=
fi

if [[ ! $1 || $1 == "--help" || $1 == "-h" ]]; then
    echo 'Usage: term [-d] mono|color|none|<terminalName>';
    echo '  -d sets default emulation for all serial port shells (takes effect on logout)'
    echo '  omitting -d makes change temporary and immediate'
    echo '  -f forces change even if not running on serial port (e.g. within "screen")'
    echo '  Terminal emulation: mono->VT-100, color->PC-ANSI/ANSI-BBS, none->no emulation'
else
    if [[ $(tr [:upper:] [:lower:] <<< $1) == "mono" ]]; then
        term="vt100"
    elif [[ $(tr [:upper:] [:lower:] <<< $1) == "color" ]]; then
        term="pcansi"
    elif [[ $(tr [:upper:] [:lower:] <<< $1) == "none" ]]; then
        term="dumb"
    else
        term="$1"
    fi
    if [[ $setgetty ]]; then
        sudo sed -i "s/\(ttyAMA0 .*\) .*$/\1 $term/" /etc/inittab;
        sudo sed -i "s/\(ttyUSB.* .*\) .*$/\1 $term/g" /etc/inittab;
        sudo init q;
        sudo pkill -f "/sbin/getty"
    else
        if [[ $force || $(tty | grep tty) ]]; then
            TERM="$term"
        else
            echo 1>&2 "Not running on serial port. No action taken. Use -f to set anyway."
        fi
    fi
fi

echo -e "$(tty) current emulation: $(tput bold)$TERM$(tput sgr0)"
echo -e "default serial port emulation at login: $(tput bold)$(grep ttyUSB /etc/inittab | sed 's/^.*ttyUSB[^ ]* .* \(.*\)$/\1/')$(tput sgr0)"