#!/bin/bash

declare -r filename='scanQr-%05d.txt' qrfilename='scanQr-%05d.png'
declare -i filenum=1 qrfilenum=1
die() {
    echo >&2 "ERROR ${0#*/}: $@"
    exit 1
}

oggPlayer=$(which ogg123)
[ "$oggPlayer" ] || die "Can't find 'ogg123' tool."
QRScanner=$(which zbarcam)
[ "$QRScanner" ] || die "Can't find 'zbarcam' tool."
readySnd=/usr/share/sounds/KDE-KStars-Sys-App-Message.ogg
scanSnd=/usr/share/sounds/KDE-KStars-Finish-Success.ogg
[ -x "$oggPlayer" ] || die "Can't execute '$oggPlayer'."
[ -x "$QRScanner" ] || die "Can't execute '$QRScanner'."
[ -r "$readySnd" ]  || die "Can't access '$readySnd'."
[ -r "$scanSnd" ]   || die "Can't access '$scanSnd'."

check4QRScanner() {
    local maj min rev
    IFS=$'.\n' read -r maj min rev < <($QRScanner --version)
    (( ( maj > 0 ) || ( min > 23 ) || ( min = 23 && rev >= 1) )) && return
    die "Require zbar-tools V >= 0.23.1 for correct binary scan."
}
getOneQr() {
      local -n _gC_res=${1:-QRCode}
      local _gC_line
      IFS= read -u $scan -r _gC_res
      _gC_res+=$'\n'
      while IFS= read -u $scan -t .02 -r _gC_line; do
          _gC_res+="$_gC_line"$'\n'
      done
      _gC_res="${_gC_res%$'\n'}"
}
check4QRScanner
exec {ogg}> >(
    exec stdbuf -o0 $oggPlayer --audio-buffer 0 -b 8 -p 0 -q - &>/dev/null)
oggpid=$!
exec {scan}< <(
    exec stdbuf -i0 $QRScanner -q --raw -Sbinary 2>/dev/null $1)
scanpid=$!

cat >&$ogg "$readySnd"


while :;do
    if read -t 0 -u $scan && getOneQr res ;then
	cat >&$ogg "$scanSnd"
	# Do something automatically here, with "$res"
	xclip <<<"$res"
    fi
    if IFS= read -sn 1 -t .2 userKey ;then
	case $userKey in
	    e ) echo EXIT.; break ;;
	    # Do something there, on user demand...
	    c ) xclip <<<"$res" ;;
	    n ) clear;cat -n <<<"$res" ;;
	    r ) echo "$res" ;;
	    s ) while printf -v file "$filename" $filenum;[ -f "$file" ] ;do
		    filenum+=1
		done
		printf "%s" "$res" >"$file" && ls -l "$file"
		;;
	    q ) while printf -v file "$qrfilename" $qrfilenum;[ -f "$file" ] ;do
		    qrfilenum+=1
		done
		qrencode -o "$file" < <(printf "%s" "$res")
		ls -l "$file"
		;;
	    p ) printf '%3dl %3dw %3dc <%q>\n' $(wc <<<"$res") "$res" ;;
	esac
    fi
done

exec {ogg}>&-
exec {scan}<&-
[ -d /proc/$oggpid ] && kill $oggpid
[ -d /proc/$scanpid ] && kill $scanpid