#!/bin/bash

# Joerg Arndt's  cpipe
# ... online at http://www.jjj.de/
# your feedback is welcome  mailto: arndt (AT) jjj.de
# version: 2021-April-02 (08:35)

#set -vx

##################################
## Examples:
# top -n 1 | cpipe root bash emacs mingetty
# ps aux | cpipe  $(whoami)'.*'\$
# ps aux | cpipe  root bash emacs mingetty

## color demo:
# echo -e '\n col1\n col2\n col3\n col4\n col5\n normal' | cpipe col1 col2 col3 col4 col5

## the tar manpage in christmas-mode:
# man tar -P cat | cpipe a b c d e

##################################


C0='' ## normal
C1='' ## bg red
C2='' ## bg green
C3='' ## bg yellow
#C4='' ## bg blue
C5='' ## bg magenta
C4='' ## bg cyan


TTYONLY=1;
while getopts :f OPT; do
    case $OPT in
        f|+f) TTYONLY=0;
            ;;
#        *)
#            usage;
#            exit 2
    esac
done
shift $[ $OPTIND - 1 ]


if [ ! -t 1 ]; then

    ## if output is a pipe then do not colorize
    ## instead insert [#1]expr[##], [#2]exp2[##]

#    C0='[##]';
#    C1='[#1]'; C2='[#2]'; C3='[#3]'; C4='[#4]'; C5='[#5]';

    ## if you prefer 'do nothing' inside a pipe:
    if [ $TTYONLY -eq 1 ]; then
        unset C0 C1 C2 C3 C4 C5
    fi

else
    ## if interrupted set:
#    trap "echo -n ''" 0 ## color to black and attributes to normal
    trap "echo -n ''" 0 ## attributes to normal
fi

P1="s/$1/${C1}&${C0}/g;"
P2="s/$2/${C2}&${C0}/g;"
P3="s/$3/${C3}&${C0}/g;"
P4="s/$4/${C4}&${C0}/g;"
P5="s/$5/${C5}&${C0}/g;"

case $# in

    0) cat
        ;;
    1) sed "$P1"
        ;;

    2) sed "$P1 $P2"
        ;;

    3) sed "$P1 $P2 $P3"
        ;;

    4) sed "$P1 $P2 $P3 $P4"
        ;;

    *)  ## only args 1,...,5 are used
        sed "$P1 $P2 $P3 $P4 $P5"
        ;;
esac


exit $?
############################################