#!/usr/bin/bash
# boxit -- a filter putting a text in a box
# +-----+         ┌─────┐
# | box | and now │ box │
# +-----+         └─────┘
# puts box around input text with tab conversion as TODO
# input is piped into stdin or from concantenating named files
#
# boxit -title titlewords ... adds a title box now
# 2010-04-05 12:26:17   bokr
#
# 2016-11-29 06:47:32   bokr
# now uses utf8 boxchars by default unless first non-help opt is -a

# Copyright (C) 2019 Bengt Richter
# License LGPLv3+: GNU LGPL 3 or later <http://gnu.org/licenses/lgpl.html>.
# This is free software: you are free to change and redistribute it.
# There is NO WARRANTY, to the extent permitted by law.

case "$1" in -h*|--h*) shift; echo "\
Usage: boxit [-a | -r ] [ -c command ] [ -h* | --h*] [ -title title_string ]
    -c command will box the output of command with command as the title.
    -a will use ascii characters, otherwise utf8 box drawing chars, -r for round corners
    Otherwise boxit puts box around input text piped into stdin, with
    optional matching title box at top, like this." \
    |boxit $1 -title "Usage"; exit;
esac

if [ "$1" ==  '-a' ];then
    asciiopt='-a'
    dashes='----------------------------------------'
    shift; hl='-'; vl='|'; ul='+'; ur='+'; ll='+'; lr='+'; tr='+'; tl='+'; td='+'; tu='+'; tx='+';
else
    asciiopt=
    dashes='────────────────────────────────────────'
    hl='─'; vl='│'; ul='┌'; ur='┐'; ll='└'; lr='┘'; tr='├'; tl='┤'; td='┬'; tu='┴'; tx='┼';
    if [ "$1" == '-r' ];then
	ul='╭'; ur='╮'; ll='╰'; lr='╯';
	## uchr {9581..9582} 10 {9584..9583} 10
	shift
    fi
fi
if [ "$1" ==  '-title' ];then shift;title="$*";fi

function stripvtesc () {
    cat $1|sed -e 's:[\x07\r]::g' -e 's:.\x08::g' -e 's:\x1B\[[^a-zA-Z]*[a-zA-Z]\x0f*::g' -e 's:\xe2\x80\x98:":g' -e 's:\xe2\x80\x99:":g'
}

function stripped_size () {
    ss="$(echo "$1"|stripvtesc)"
    echo -n ${#ss}
}
## -c command
if [ "$1" ==  '-c' ];then
    shift; title="$@"
    stdboth="$($@ 2>&1)"
    echo "$stdboth" |boxit $asciiopt -title "$title"
    exit;
fi
    
oldIFS="$IFS"; IFS=''
i=0; txt[0]=''; mxwidth=$(stripped_size "$title")
while read -r line; do
    if [ "$i" == "0" -a -z "$line" ];then continue;fi # dump leading blank lines
    stripped_nc="$(stripped_size "$line")" #|stripvtesc)"
    (( ${stripped_nc} > $mxwidth ? mxwidth=${stripped_nc} : $mxwidth ))
    txt[$i]="$line"
    ((i++))
done
((i--)) # to last line
rx='[ \t]+'
while true;do
    if [ "$i" -le 0 ];then break;fi
    if [ -z "$(echo "${txt[$i]}"|tr -d $' \t')" ];then
	unset txt[$i]
	((i--))
    else
	break
    fi
done

spaces='                                        '
while (( ${#dashes} < $mxwidth )); do
    dashes="$dashes$dashes" # double
    spaces="$spaces$spaces" # double
done
mx3=$mxwidth

if [ "$title" != "" ]; then
    nsp=$(( $mxwidth-$(stripped_size "${title}" )))
    # center it
    halfsp=$(( $nsp / 2 ))
    sp1="${spaces:0:$(( $nsp / 2 ))}"; sp2="${spaces:0:$(($nsp - $halfsp))}"
    echo "$ul$hl${dashes:0:$mx3}$hl$ur"
    echo "$vl ${sp1}$title${sp2} $vl"
    echo "$tr$hl${dashes:0:$mx3}$hl$tl"
else    
    echo "$ul$hl${dashes:0:$mx3}$hl$ur"
fi
for itm in "${txt[@]}"; do
    sszitm=$(stripped_size "${itm}")
    sptomax=$(( $mxwidth-$sszitm ))
    sp="${spaces:0:$sptomax}"
    echo "$vl $itm${sp} $vl"
done
echo "$ll$hl${dashes:0:$mx3}$hl$lr"
IFS="$oldIFS"