#!/bin/sh
# Copyright © 2000-2013 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=60
url="http://static-cdn.justin.tv/previews/live_user_dnalounge-630x473.jpg"
file="html/live.jpg"
colorbars=colorbars.jpg
tmp="${file}~"
tmp2="${file}2~"
verbose=false

too_old() {
  if [ -z `find $1 -prune -mmin +240 -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_user_dnalounge-630x473.jpg"

  # we get this is there's a failure
  crud="screencap_404_630x473.png 404_preview.png"


  # 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 `date`: "downloading $url" >&2
  fi

  rm -f $tmp $tmp2 $crud
  wget -t1 -T5 -q $url

  if ! [ -s $tmp ]; then			# zero-length file

    if [ "$verbose" = true ]; then
      echo `date`: "zero-length file: $tmp" >&2
      ls -lG --full-time $tmp
    fi
    rm -f $tmp
  fi


  if [ -f $tmp ] && ! too_old $tmp; then

    convert -crop 480x360+75+56 $tmp $tmp2 >/dev/null 2>&1
    touch -r $tmp $tmp2
    mv $tmp2 $tmp

    if cmp -s $tmp $file ; then
      if [ "$verbose" = true ]; then
         echo `date`: "image hasn't changed" >&2
      fi
      rm -f $tmp
    fi
  fi


  if [ ! -f $tmp ]; then	# not downloaded, or unchanged
    cp -p $file $tmp
  fi


  if too_old $tmp; then
    if [ "$verbose" = true ]; then
      echo `date`: "too old: $tmp" >&2
      ls -lG --full-time $tmp
    fi
    cp -p $colorbars $file
    rm -f $tmp
  else
    mv $tmp $file
  fi


  if [ "$verbose" = true ]; then
    echo `date`: "done." >&2
    ls -lG --full-time $file
    echo ""
  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 `date`: "started" | log_lines
pull_loop 2>&1 | log_lines

exit 0