#!/bin/sh
# Copyright © 2000, 2002 Jamie Zawinski <jwz@dnalounge.com>
#
# Permission to use, copy, modify, distribute, and sell this software and its
# documentation for any purpose is hereby granted without fee, provided that
# the above copyright notice appear in all copies and that both that
# copyright notice and this permission notice appear in supporting
# documentation.  No representations are made about the suitability of this
# software for any purpose.  It is provided "as is" without express or 
# implied warranty.
#
# Created: 16-Aug-2000.

progname=slideshow-pull

delay=10
url="http://medulla.dnalounge.com/cam/live.jpg"
file="html/live.jpg"
colorbars=colorbars.jpg
tmp="${file}~"
#verbose=true

too_old() {
  if [ -n `find $1 -prune -mmin +60 -print 2>&-` ]; then
    return 1
  else
    return 0
  fi
}

pull_one() {

 # wget doesn't save the proper file date if -O is specified...
 #  wget -q -O $tmp $url
 # so instead, write ./live.jpg and rename to html/live.jpg to get the date.
 tmp="live.jpg"

 # Arrgh!  Note that wget takes 15 minutes to time out on host that 
 # won't connect() even if you specify -T!

 if [ "$verbose" = true ]; then
   echo "downloading..." >&2
 fi

 rm -f $tmp
 wget -t1 -T5 -q $url

 if [ -s $tmp ]; then
   # we downloaded a non-zero-length file
   if too_old $tmp; then
     # it's stale
     if [ "$verbose" = true ]; then
       echo "downloaded image is more than 1 hour old:" >&2
       ls -lG --full-time $tmp
     fi
     cp -p $colorbars $file
   else
     # it's recent
     mv $tmp $file
     if [ "$verbose" = true ]; then
       echo "done." >&2
     fi
   fi
 else
   # file was not downloaded, or was 0-length
     if [ "$verbose" = true ]; then
       echo "no image downloaded" >&2
     fi
   cp -p $colorbars $file
 fi

 if [ "$verbose" = true ]; then
   ls -lG --full-time $file
 fi

 sleep $delay
}


pull_loop() {
  while true ; do
    pull_one
  done
}

# log all stdout/stderr text to syslog
log_lines() {
  while read line ; do
    logger -st "$progname" -- "$line"
  done
}

echo "started at `date`" | log_lines
pull_loop 2>&1 | log_lines

exit 0