#!/bin/bash
#
# Syntax:  pd [-h] [pdf_file [...]]
#
# Purpose: Shows one or more pdf file using acroreader, okular, xpdf, epdfview,
#          ghostview, or evince (where the first command of this list that can 
#          be found is used).
#          The -h flag shows the help info for this command.

# Created: Jun 30, 2016       by Bart De Schutter
# Last revised:
#
# See http://www.deschutter.info/util/scripts.html for the latest version of
# this script.

# Status: public
# Category: pdf, latex

if [  $# -ge 1   -a   "$1" = "-h"  ];
then
   sed '/^$/q;/^#!/d;s/^# //;s/^#//' $0 >&2
   exit 1
fi

#if [ $# -ne 0 ];
#then 
#   echo >&2
#   echo >&2 "ERROR: ${0##*/} requires no input arguments."
#   echo >&2
#   sed '/^$/q;/^#!/d;s/^# //;s/^#//' $0 >&2
#   exit 1
#fi


pdf_viewer=$(type -p acroread)
options=""
if [ -z "$pdf_viewer" ]
then
   pdf_viewer=$(type -p okular)
   options=""
   if [ -z "$pdf_viewer" ]
   then
      pdf_viewer=$(type -p xpdf)
      options="-z page"
      if [ -z "$pdf_viewer" ]
      then
         pdf_viewer=$(type -p epdfview)
         options=""
         if [ -z "$pdf_viewer" ]
         then
            pdf_viewer=$(type -p ghostview)
            options=""
            if [ -z "$pdf_viewer" ]
            then
               pdf_viewer=$(type -p evince)
               options=""
               if [ -z "$pdf_viewer" ]
               then
                  echo >&2
                  echo >&2 "ERROR: No pdf viewer found on this system."
                  echo >&2
                  exit 1
               fi
            fi
         fi
      fi
   fi
fi

if [  $# -eq 0 ];
then
   pdffile=$( (ls -t *.pdf | head -n 1) 2>/dev/null)
   if [ -n "$pdffile" ];
   then
      $pdf_viewer $options "$pdffile" &
   else
      echo "No .pdf files found in the current directory."
   fi
else
   for pdffile in "$@"
   do
      echo "Viewing $pdffile"
      $pdf_viewer $options "$pdffile" 
   done
fi