help

#!/bin/sh

EXCLUDE="\[|ash|addgroup|adduser|bbconfig|busybox|chpassed|conspy|cryptpw|"
EXCLUDE=$EXCLUDE"cttyhack|delgroup|deluser|false|gfxsave.sh|login|"
EXCLUDE=$EXCLUDE"mdev|mkpasswd|non-live-cmdline|passwd|pipe_progress|"
EXCLUDE=$EXCLUDE"pivot_root|ret|sulogin|switch_root|test-|tsplash|"
EXCLUDE=$EXCLUDE"vlock|xargs|yes|true|printf|"
EXCLUDE=$EXCLUDE"auto-load-modules|bb-chroot|killall5|umount-|live-chroot|"
EXCLUDE=$EXCLUDE"load-live-modules|usb-report.sh|usb2-re-enable"

main() {
    local dir=${1:-/bin}
    set_color

    echo -e "$white\nAvailable commands:"
    printf "$green"
    column $(list_execs $dir)
    printf "$NC"
    echo -e "\nUse $(aq Shift+PgUp) and $(aq Shift+PgDn) to scroll"
    echo "For many commands the $(gq --help) option gives more info.  Example:  $(gq ls --help)"

}

aq() { echo -n "$amber$*$NC" ;}
gq() { echo -n "$green$*$NC" ;}


column() {
    local swidth=$(stty size | cut -d" " -f2)
    local item width max_width=0

    for item; do
        width=$(echo "$item" | wc -m)
        [ $max_width -lt $width ] && max_width=$width
    done
    max_width=$((max_width + 1))
    local cnt=0 cols=$(( (swidth -1) / max_width))

    # for item; do
    #     printf "%-${max_width}s" "$item"
    #     cnt=$(((cnt + 1) % cols))
    #     [ $cnt = 0 ] && echo
    # done
    # [ $cnt = 0 ] || echo

    rows=$(($# / cols + 1))
    for row in $(seq 1 $rows); do
        cnt=0
        for item; do
            cnt=$((cnt + 1))
            [ $(((rows + cnt - row) % rows)) = 0 ] || continue
            #printf "%4s" $cnt
            printf "%-${max_width}s" "$item"
        done
        echo
    done

}

list_execs() {
    local dir=$1 name file
    for name in $(ls $dir); do
        file="$dir/$name"
        [ -d $file ] && continue
        [ -x $file ] || continue
        echo $name | egrep -q "^($EXCLUDE)" && continue
        echo $name
    done
}

set_color() {
    local e=$(printf "\e")

         black="$e[30m";        red="$e[31m";      green="$e[32m";
         amber="$e[33m";       blue="$e[34m";    magenta="$e[35m";
          cyan="$e[36m";    lt_grey="$e[0;37m";

          grey="$e[1;30m";    rose="$e[1;31m";  lt_green="$e[1;32m";
        yellow="$e[1;33m";  violet="$e[1;34m";      pink="$e[1;35m";
       lt_cyan="$e[1;36m";   white="$e[1;37m";

            NC="$e[0m";

      black_bg="$e[40m";     red_bg="$e[41m";    green_bg="$e[42m";
      amber_bg="$e[43m";    blue_bg="$e[44m";  magenta_bg="$e[45m";
       cyan_bg="$e[46m";   white_bg="$e[47m"
           rev="$e[7m";  under_line="$e[4m";         bold="$e[1m"

    clear="$e[2;J"; cursor_off="$e[?25l"; cursor_on="$e[?25h"

}

main "$@"