#!/bin/bash

id=$1
ext=$2
set_size=$3

server=cdmr@digitalmycology.com:images.digitalmycology.com
images=public/images

db_config=config/database.yml
username=`grep -A 20 production: $db_config | grep username: | head -1 | sed 's/.*: *//'`
database=`grep -A 20 production: $db_config | grep database: | head -1 | sed 's/.*: *//'`
password=`grep -A 20 production: $db_config | grep password: | head -1 | sed 's/.*: *//'`

orig=$images/orig/$id.$ext
orig_layers=$images/orig/$id-'*'.jpg
full=$images/orig/$id.jpg
huge=$images/1280/$id.jpg
large=$images/960/$id.jpg
medium=$images/640/$id.jpg
small=$images/320/$id.jpg
thumb=$images/thumb/$id.jpg

log=log/process_image.$$
log2=log/process_image.log
email=webmaster@mushroomobserver.org

path=(. /bin /usr/bin /usr/local/bin)

errors=0

if [[ $RAILS_ENV == 'production' ]]; then
    production=1
else
    production=0
fi

# ----------------------------
#  Help message.
# ----------------------------

if [[ $1 == '-h' || $1 == '--help' ]]; then cat <<-EOH; exit -1

	USAGE:
	    script/process_image <id> <ext> <0|1>

	DESCRIPTION:
	    This is used by the webserver to resize and transfer uploaded
	    images to the image server.  It is intended to run
	    asynchronously.  One of these jobs is spwaned for each image
	    uploaded.  Each process first creates temporary soft links to a
	    place-holder image so that the user sees at least something while
	    waiting for the images to be processed.  Then it runs convert
	    (from ImageMagick suite) to downsize the image, first checking
	    that no one else is running convert.  If another process is
	    running convert, it sleeps a few seconds and tries again.  After
	    images are resized, it transfers them to the image server using
	    scp, again waiting for other scp jobs to finish first.  It emails
	    the webmaster if there are any errors.
	
	FILES:
	    webmaster       $email
	    image server    $server
	    error log       $log2

	EOH
fi

# --------------------------------------------------
#  Run a command, logging both command and result.
#  Sets errors to true if anything fails.
# --------------------------------------------------

function run() {
    echo "`date`>" $* >> $log
    if !($* >> $log 2>&1); then
        errors=1
        echo '**** FAILED ****' >> $log
    fi
}

# ----------------------------
#  Resize images.
# ----------------------------

# Wait for other conversions to finish first.
while (ps -e | grep ' convert$' > /dev/null); do sleep 5; done

# Do we need to convert the original to a JPEG?
if [[ $orig != $full ]]; then
  run convert -quality 90 $orig $full

  # If there are multiple layers, ImageMagick saves them as 1234-N.jpg.
  # Take the first one, and delete the rest.
  if [[ ! -e $full ]]; then
    biggest_layer=`ls -rS $orig_layers | tail -1`
    if [[ -e $biggest_layer ]]; then
      run mv $biggest_layer $full
      run rm $orig_layers
    fi
  fi
fi

# Do we need to report the image size back to Rails?
if (( $set_size )); then
  run script/jpegsize --set $id $full
fi

# Create the other sizes now.  Image processing theory says that reducing
# images by no more than 50% at a time is optimal.
# run convert -thumbnail '1280x1280>' -quality 70 $full $huge
# run convert -thumbnail '960x960>' -quality 70 $huge $large
# run convert -thumbnail '640x640>' -quality 70 $huge $medium
# run convert -thumbnail '320x320>' -quality 80 $medium $small
# run convert -thumbnail '160x160>' -quality 90 $small $thumb

run jpegresize 1280x1280 -q 70 --max-size $full $huge
run jpegresize 960x960 -q 70 --max-size $huge $large
run jpegresize 640x640 -q 70 --max-size $huge $medium
run jpegresize 320x320 -q 80 --max-size $medium $small
run jpegresize 160x160 -q 90 --max-size $small $thumb

# ----------------------------
#  Transfer images.
# ----------------------------

# Wait for other transfers to finish first.
while (ps -e | grep ' scp$' > /dev/null); do sleep 5; done

# Careful!  Don't do this in test mode!
if (( $production )); then
  run scp $thumb  $server/thumb/$id.jpg
  run scp $small  $server/320/$id.jpg
  run scp $medium $server/640/$id.jpg
  run scp $large  $server/960/$id.jpg
  run scp $huge   $server/1280/$id.jpg
  run scp $full   $server/orig/$id.jpg
  if [[ $orig != $full ]]; then
    run scp $orig   $server/orig/$id.$ext
  fi
fi

# ------------------------------
#  Report errors to webmaster.
# ------------------------------

cat $log >> $log2
if (( $production )); then
  if (( $errors )); then
    mutt -s '[MO] process_image' $email < $log
  else
    mysql -q -u "$username" -p"$password" "$database" -e "UPDATE images SET transferred=TRUE WHERE id=$id;"
  fi
fi
rm -f $log

exit $errors