#!/bin/bash

#convert image.bmp  image.txt
#If you just one one color at a X,Y crop it first...
#convert image.bmp  -crop 1x1+5+6  +repage image.txt


if [ -z "$(which convert 2>/dev/null)" ];then
   echo "Install ImageMagick and try again";
   exit 1;
fi

set -e

# directory containing the photos to include in gallery
sourcephotodir=photos

# the directory in to which to put the overlays images that are used to
# change the border colour on mouseover
overlaysdir=overlays;

# delete any pre-existing thumbnails
rm -rf $overlaysdir;
mkdir -p $overlaysdir;
rm -f *png;

# seed $RANDOM with pid and seconds since epoch
RANDOM=$$$(date +%s);

for i in ${sourcephotodir}/*;do
   # rn is the number to pass to the -polaroid operation
   rn=$(echo $RANDOM%15 | bc);
   # rn will be created positive, so make it negative 50% of the time
   srn=$(echo $RANDOM%2 | bc);
   if [ $srn -eq 0 -a $rn -ne 0 ];then # let rn=0-0  doesn't work
      let rn=0-${rn};
   fi

   fn=$(basename ${i});
   # nfn is the filename for the thumbnail. the same name is used but with jpg
   # swapped to png so imagemagick creates a png image
   nfn=${fn/.jpg/.png};
   # set height and width for the thumbnails
   thumbwidth=150;
   thumbheight=100;

   ow=$(identify -format %w ${i});
   oh=$(identify -format %h ${i});
   # figure out if the source photo has a height larger than it's width and if so
   # switch the thumbnail height and width around
   if [ ${oh} -gt ${ow} ];then
      foo=${thumbwidth};
      thumbwidth=${thumbheight};
      thumbheight=${foo};
   fi

   # create a thumbnail, strip out any profiles etc. 
   convert ${i} -strip -thumbnail  ${thumbwidth}x${thumbheight}  ${nfn};

   # copy the thumbnail to the overlays dir for later processing
   cp ${nfn} ${overlaysdir}/

   # get width and height of the thumbnail for later use
   w=$(identify -format %w ${nfn});
   h=$(identify -format %h ${nfn});

   # apply polaroid operation to the thumbnail
   convert $nfn -bordercolor snow -background black  -polaroid $rn $nfn;

   #which optipng &>/dev/null && optipng -o7 -quiet $nfn;

   # now create the overlay image
   cd ${overlaysdir};
   # reduce the image to one colour then negate it and extract the value
   color=$(convert ${nfn} -colors 1 -depth 8 -negate -format "%c" histogram:info:  | sort -nr | head -1 | cut -d '#'  -f 2 | cut -d ' ' -f 1);
   # check a value was found and use a fall back colour if not
   if [ -z "${color}" ];then
      color='#ff0000';
   else   
      color="#${color}";
   fi

    # create a new version of the thumbnail that's 95% the size and rotateed
    # by the same amount the polaroid version will be for later use
    convert ${nfn} -matte -background none -resize 95% -rotate ${rn} foo.png;

    # apply polaroid operation to the thumbnail, using border colour obtained earlier
    convert ${nfn} -bordercolor ${color} -background transparent -polaroid ${rn} ${nfn};

    # use the 95% size and rotated version of the thumbnail created earlier to
    # punch a transparent hole in to the thumbnail to reduce file size.
    g=-4;
    composite -compose Dst_Out  -gravity center -geometry ${g}${g} foo.png ${nfn} -matte ${nfn};

   rm -f foo.png

   #which optipng &>/dev/null && optipng -o7 -quiet $nfn;

   # go back to the previous working dir to process the next image
   cd - >/dev/null;
done

# because if you've re-generated all the images then the web page needs to be
# regenerated so it contains the correct width/height attributes for all the img
# elements
./makehtml