#!/bin/sh
# reviewimg - Review some images, optionally rotate or name them
#
# Requires: ImageMagick
#           xloadimage
#
# Usage:
#
# reviewimg [-n] [-r option] [path]
# 
# Accepts a file or directory as an argument. If omitted, the current
# working directory will be used.
#
# Options:
# 
#   -n   Choose only images changed today. If no path has been specified, the 
#        current working directory is examined for images.
#   -r   Specify how rotated images should be handled:
#        'none' - Don't want to rotate images
#        'copy' - Create rotated image as copy (this is the default option)
#                 e.g. original: filename.jpg rotated: filenamer.jpg
#        'replace' - Overwrite original file with rotated image 
#
# TODO / BUGS:
#    o Quality of rotated images is worse than orginals - ImageMagick uses
#      default sampling factor - not same as original image. 
#    o Have an option to ask for dest filename
#    o Don't process files that have been overwritten
#    o Option to name images
#    o Option to dump EXIF info (otherwise it is lost with 'replace')
#    o usage synopsis with -h option
#
# Author: Graham Bleach <code@darkskills.org.uk> 
# Version: 0.1

# errors
E_BADUSAGE=1
E_CMDFAIL=2
E_MISSING_SW=3
E_NO_X=4

# --- functions ---

rotate () {
   while read -p "Rotate [0/90/180/270] degrees:" -n 1 response < /dev/tty
   do
      case "$response" in
         0) DEG='0'; echo; return;;
         9) DEG='+90'; echo; break;;
         1) DEG='+180'; echo; break;;
         2) DEG='+270'; echo; break;;
         *) echo -e "\nUnrecognised response $response";;
      esac
   done

   if [ "$ROTATE" = 'replace' ]
   then
      DESTFILE="$FILE"
   else
      DESTFILE="${IMGDIR}/${IMGBASEFN}r.${IMGEXTN}"
      if [ -e "$DESTFILE" ]
      then
         while read -p "File $DESTFILE exists, overwrite [y/n]" -n 1 \
	           response < /dev/tty
         do
            case "$response" in
               y) echo; break;;
	       n) echo; return;;
	       *) echo -e "\nUnrecognised response: $response";;
            esac
         done
      fi   
   fi

   convert -rotate "$DEG" "$FILE" "$DESTFILE" >/dev/null 2>&1
   RVAL=$?

   if [ $RVAL -ne 0 ]
   then
      echo "Error rotating file $FILE"
      exit $E_CMDFAIL
   fi
}

# -- option defaults --
# looking for new files
NEWFILES=0
# filetypes supported by ImageMagick that should be ignored
IGNORETYPES='TXT PDF' 
ROTATE='copy'

# use this to store list of files processed
declare -a PROCFILES

# -- option parsing & checking
while getopts "nr:" OPTION
do
   case $OPTION in
      n) NEWFILES=1;;
      r) ROTATE="$OPTARG";;
      ?) exit $E_BADUSAGE;;
   esac
done

shift $(($OPTIND - 1))

if [ -z "$1" ]
then
   IMGPATH='.'
else
   IMGPATH="$1"
fi

if [ -d "${IMGPATH}" ]
then
   MAXDEPTH=1
else
   MAXDEPTH=0
fi

if [ $NEWFILES == 1 ]
then
   FINDOPTS='-ctime -1' 
else
   FINDOPTS=
fi

if [ "$ROTATE" != 'copy' ] && [ "$ROTATE" != 'replace' ] \
   && [ "$ROTATE" != 'none' ]
then
   echo "Invalid rotation option: $ROTATE"
   exit $E_BADUSAGE
fi

# Check ImageMagick installed
which identify >/dev/null 2>&1
RVAL=$?

if [ $RVAL != 0 ]
then
   echo "ImageMagick appears not to be installed!"
   exit $E_MISSING_SW
fi

# Check xview / xloadimage installed
which xview >/dev/null 2>&1
RVAL=$?

if [ $RVAL != 0 ]
then
   echo "xview appears not to be installed!"
   exit $E_MISSING_SW
fi

# find geometry of root window
# if there's an error, maybe X is not in use ;-)
XINFO=$(xwininfo -root)
RVAL=$?

if [ $RVAL != 0 ]
then
   echo "ERROR: Cannot get attributes of X root window ..."
   echo "Perhaps X is not running?"
   exit $E_NO_X
fi

# get X geometry info
XWIDTH=$(echo ${XINFO} | sed 's/^xwininfo: .*Width: \([0-9]\{1,\}\) .*$/\1/')
XHEIGHT=$(echo ${XINFO} | sed 's/^xwininfo: .*Height: \([0-9]\{1,\}\) .*$/\1/')

find "${IMGPATH}" -type f -maxdepth ${MAXDEPTH} ${FINDOPTS} -print | 
while read FILE
do
   ID=$(identify -format '%m:%w:%h:%e:%t:%d' "${FILE}" 2>/dev/null)
   RVAL=$?

   if [ $RVAL != 0 ]
   then
      # echo "Cannot identify file ${FILE} - probably not an image. Ignored."
      continue
   fi

   # if someone uses ':' in filenames we're in trouble ;-)
   IMGFORMAT=$(echo ${ID} | cut -d':' -f1)
   IMGWIDTH=$(echo ${ID} | cut -d':' -f2)
   IMGHEIGHT=$(echo ${ID} | cut -d':' -f3)
   IMGEXTN=$(echo ${ID} | cut -d':' -f4)    # file ext e.g. '.JPG'
   IMGBASEFN=$(echo ${ID} | cut -d':' -f5)  # filename to ext e.g. 'IMG_1437'
   IMGDIR=$(echo ${ID} | cut -d':' -f6)     # directory containing file

   # Some types should be ignored. For example, some formats are supported
   # by ImageMagick, but are not really images e.g. TXT, PDF
   for FMT in $IGNORETYPES
   do
      if [ "$IMGFORMAT" = "$FMT" ]
      then     # ignore file - iterate outer loop
         continue 2
      fi
   done

   # Viewing the picture with xview
   # we scale the picture to fit nicely on the screen
   if [ $IMGWIDTH -le $XWIDTH ] && [ $IMGHEIGHT -le $XHEIGHT ]
   then
      ZOOM='100%'
   else
      PERWID=$[${XWIDTH}*100/$IMGWIDTH]
      PERHT=$[${XHEIGHT}*100/$IMGHEIGHT]

      if [ $PERWID -gt $PERHT ]
      then
         ZOOM="$[${PERHT}-5]%"
      else
         ZOOM="$[${PERWID}-5]%"
      fi
   fi

   xview -zoom "$ZOOM" "$FILE" >/dev/null 2>&1
   RVAL=$?

   if [ $RVAL -ne 0 ]
   then
      echo "Error viewing file $FILE"
      exit $E_CMDFAIL
   fi

   if [ "$ROTATE" != 'none' ]
   then
      rotate 
   fi 
done