#!/usr/bin/env bash
# HEADER
#=======================================================================
#
#  qrcode -- make a QR code for a given URL.
#
#  SYNOPSIS
#    qrcode <URL> output <outfile.pdf>
#
#  DESCRIPTION
#    Shell script to make a PDF file with a QR code corresponding to a
#    given URL. It uses LaTeX to get a nicer output than `qrencode`.
#
#  POSITIONAL ARGUMENT
#    <URL>                      URL
#
#  OPTIONS
#    -h|--help                  display this help and exit
#    -o|output <outfile.pdf>    PDF outfile name
#
#  EXAMPLE
#    $ qrcode nmesnier.free.fr -o QR.pdf
#
#  DEPENDENCIES
#    - latex, dvips, ps2pdf (ghostscript)
#    - GNU coreutils
# 
#  Copyright (C) 2020 Nicolas Mesnier <nmesnier@free.fr>
#
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License version 3 or
#  above as published by the Free Software Foundation.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program. If not, see <http://www.gnu.org/licenses/>.
#
#=======================================================================
# END_OF_HEADER
#-----------------------------------------------------------------------
Help(){
    # Read header to display help and version
    BOH=$(head -200 ${0} | grep -n "^# HEADER" | cut -f1 -d:)
    EOH=$(head -200 ${0} | grep -n "^# END_OF_HEADER" | cut -f1 -d:)
    head -$(($EOH-1)) ${0} | tail -$(($EOH-$BOH-1)) \
        | grep -e "^#$" -e "^# " | sed -e "s/^#=*//g"
}
#-----------------------------------------------------------------------
__MakeQR__(){
    # Input:
    #   $1: URL
    #   $2: PDF file name
    # Output:
    #   PDF file
URL=${1}
QRFILE=${2%.pdf*}
echo $QRFILE
if [ ${URL:0:4} != "http" ];then
    URL="http://"${URL}
fi
cat > ${QRFILE}".tex" <<EOF
\documentclass[a4paper,10pt]{article}
\usepackage[utf8]{inputenc}
\usepackage{color,calc,graphicx}
\usepackage{pstricks}
\usepackage{pst-barcode}
\usepackage[paperwidth=1in, paperheight=1in, textwidth=1in, textheight=1in, centering]{geometry}
\begin{document}\noindent
\begin{pspicture}(1in, 1in)
\psbarcode[linecolor=black]{${URL}}{width=1.0 height=1.0}{qrcode}%
\end{pspicture}
\end{document}
EOF
latex ${QRFILE}".tex"
dvips ${QRFILE}".dvi"
ps2pdf ${QRFILE}".ps"
for extension in "aux" "dvi" "log" "tex" "ps";do
    rm ${QRFILE}"."${extension}
done
}
#-----------------------------------------------------------------------
# *** get options ***
#-----------------------------------------------------------------------
URL=""
OUTFILE="QRcode"
while [[ ${1} ]]; do
    case "${1}" in
        -h|--help) 
            Help
            exit 0 ;;
        # *** run function
        -o|output)
            if [ -f ${2} ]; then
                read -p " File \"${2}\" allready exists. Replace? y/[n]  " rep
                case ${rep} in
                    [Yy]* )
                        OUTFILE=${2}
                        ;;
                    * ) exit 1;;
                esac
            else
                OUTFILE=${2}
            fi
            shift
            ;;
        *)
            URL=${1}
            ;;
    esac
    if ! shift; then
        echo 'Missing parameter argument.' >&2
        exit 1
    fi
done
#-----------------------------------------------------------------------
# *** run
#-----------------------------------------------------------------------
if [ ! -z "${URL}" ];then
    __MakeQR__ ${URL} ${OUTFILE}
fi
#====================================================================eof
# vim: set tw=72 ts=4 sw=4 nu: