#!/bin/bash
#
# Developed by Fred Weinhaus 3/19/2009 .......... revised 4/25/2015
#
# ------------------------------------------------------------------------------
# 
# Licensing:
# 
# Copyright © Fred Weinhaus
# 
# My scripts are available free of charge for non-commercial use, ONLY.
# 
# For use of my scripts in commercial (for-profit) environments or 
# non-free applications, please contact me (Fred Weinhaus) for 
# licensing arrangements. My email address is fmw at alink dot net.
# 
# If you: 1) redistribute, 2) incorporate any of these scripts into other 
# free applications or 3) reprogram them in another scripting language, 
# then you must contact me for permission, especially if the result might 
# be used in a commercial or for-profit environment.
# 
# My scripts are also subject, in a subordinate manner, to the ImageMagick 
# license, which can be found at: http://www.imagemagick.org/script/license.php
# 
# ------------------------------------------------------------------------------
# 
####
#
# USAGE: mapcolors [-f file] [-s safecolor] [-m] [-a] [-d depth] [-t type] infile outfile
# USAGE: mapcolors [-help]
#
# OPTIONS:
#
# -f      file               Space delimited text file containing "from" and "to" colors; 
#                            Any valid IM color is allowed;
# -s      safecolor          Any color not used in the image; To be used as intermediary color;
#                            Any valid IM color is allowed including none;
#                            The default=none
# -m                         Monitors the progess by printing a comment to the terminal for 
#                            every color processed.
# -a                         Disables transparency for the output image; Values are on or off;
#                            The default leaves it as determined by the input image and processing.
# -d      depth              Desired depth for output image, relevant to your IM Q level.
#                            default is to leave it according to the input and processing.
# -t      type				 Type forces the resulting image class to be either: 
#                            palette or palettematte. The default is the leave the image class 
#                            as determined by the input image and the processing.
#
###
#
# NAME: MAPCOLORS 
# 
# PURPOSE: Maps or translates one set of colors in an image to another set of colors.
# 
# DESCRIPTION: MAPCOLORS maps (or translates or changes) one set of colors in an image to 
# another set of colors. The color pairs must be provided in a text file as a "from" color 
# separated by one or more space followed by a "to" color, one pair per row in the file. 
# 
# 
# OPTIONS: 
#
# -f file ... File containing space delimeted pairs of colors, one pair per row. The first color 
# will be mapped or changed to the second color using a safecolor as intermediary. 
# Any valid IM color is allowed such that it does not include the safecolor. 
# See http://imagemagick.org/script/color.php
# 
# -s safecolor ... SAFECOLOR is the safe color to use as the intermediary in the mapping 
# process. It must not a color that exists already in the input image. 
# Any valid IM color is allowed. See http://imagemagick.org/script/color.php
# For mapping colors that do not include transparency, use the default=none, but do not use 
# none for any "from" or "to" color in the file. If you want to change transparnent colors, then 
# you need to find some other non-used color in the image for the safecolor.
# 
# -m ... Enables progress monitoring by printing each color change to the terminal 
# as it is processed. Use this when you have a large number of colors to map, since process 
# is rather slow depending upon image size and number of colors to change.
# 
# -a ... Disables transparency in the resulting image. Use only if you know there are no 
# transparent colors left or created in the output image. The default is to leave the 
# transparency as determined by the input image and the processing.
# 
# -d depth ... Depth is the depth of the resulting image. Allowed values depend on the IM Q level 
# of your IM build. You may set the depth to the smalles value that will account for 
# all the colors in your image. The default is to leave it as determined by the input image's 
# depth and processing.
# 
# -t type ... TYPE controls the image class of the resulting image. The default is to leave the 
# image class unchanged. Other choices are palette or palettematte. They will force the image class 
# to be pseudoclass rather than directclass. For some image formats and processing this can lead 
# to smaller file sizes, but in other cases it appears that leaving it unchanged results in smaller 
# files sizes. You may have to play with this for your image format.
# 
# Note: This script probably will not work for versions of IM prior to 6.4.1.4 due to a bug in +opaque
# 
# CAVEAT: No guarantee that this script will work on all platforms, 
# nor that trapping of inconsistent parameters is complete and 
# foolproof. Use At Your Own Risk. 
# 
######
#

# set default values
colors_file=""
safecolor="none"	# any non used color or none
monitor=""			# on enables monitor progress to terminal
alpha=""			# disable transparency flag; 
depth=""			# image depth desired or ""
type=""				# palette or palettematte or ""

# set directory for temporary files
dir="."    # suggestions are dir="." or dir="/tmp"

# set up functions to report Usage and Usage with Description
PROGNAME=`type $0 | awk '{print $3}'`  # search for executable on path
PROGDIR=`dirname $PROGNAME`            # extract directory of program
PROGNAME=`basename $PROGNAME`          # base name of program
usage1() 
	{
	echo >&2 ""
	echo >&2 "$PROGNAME:" "$@"
	sed >&2 -e '1,/^####/d;  /^###/g;  /^#/!q;  s/^#//;  s/^ //;  4,$p' "$PROGDIR/$PROGNAME"
	}
usage2() 
	{
	echo >&2 ""
	echo >&2 "$PROGNAME:" "$@"
	sed >&2 -e '1,/^####/d;  /^######/g;  /^#/!q;  s/^#*//;  s/^ //;  4,$p' "$PROGDIR/$PROGNAME"
	}


# function to report error messages
errMsg()
	{
	echo ""
	echo $1
	echo ""
	usage1
	exit 1
	}


# function to test for minus at start of value of second part of option 1 or 2
checkMinus()
	{
	test=`echo "$1" | grep -c '^-.*$'`   # returns 1 if match; 0 otherwise
    [ $test -eq 1 ] && errMsg "$errorMsg"
	}

# test for correct number of arguments and get values
if [ $# -eq 0 ]
	then
	# help information
   echo ""
   usage2
   exit 0
elif [ $# -gt 12 ]
	then
	errMsg "--- TOO MANY ARGUMENTS WERE PROVIDED ---"
else
	while [ $# -gt 0 ]
		do
			# get parameter values
			case "$1" in
		     -help)    # help information
					   echo ""
					   usage2
					   exit 0
					   ;;
				-f)    # get colormap file
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID COLOR MAP FILE SPECIFICATION ---"
					   checkMinus "$1"
					   colors_file="$1"
					   ;;
				-s)    # get safecolor
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID SAFECOLOR SPECIFICATION ---"
					   checkMinus "$1"
					   safecolor="$1"
					   ;;
				-m)    # get monitor
					   #shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   #errorMsg="--- INVALID MONITOR SPECIFICATION ---"
					   #checkMinus "$1"
					   monitor="on"
					   ;;
				-a)    # get alpha
					   #shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   #errorMsg="--- INVALID ALPHA SPECIFICATION ---"
					   #checkMinus "$1"
					   alpha="off"
					   ;;
				-d)    # get depth
					   shift  # to get the next parameter
					   # test if parameter starts with minus sign 
					   errorMsg="--- INVALID DEPTH SPECIFICATION ---"
					   checkMinus "$1"
					   depth=`expr "$1" : '\([0-9]*\)'`
					   [ "$depth" = "" ] && errMsg "--- DEPTH=$depth MUST BE AN INTEGER ---"
					   ;;
				-t)    # get type
					   shift  # to get the next parameter - type
					   # test if parameter starts with minus sign
					   errorMsg="--- INVALID TYPE SPECIFICATION ---"
					   checkMinus "$1"
					   # test type values
					   type="$1"
					   case "$type" in
							palette|palettematte) ;; # do nothing - valid type
							*)  errMsg "--- TYPE=$type IS NOT A VALID VALUE ---" ;;
					  esac
					  ;;
				 -)    # STDIN and end of arguments
					   break
					   ;;
				-*)    # any other - argument
					   errMsg "--- UNKNOWN OPTION ---"
					   ;;
		     	 *)    # end of arguments
					   break
					   ;;
			esac
			shift   # next option
	done
	# get infile, outfile and lutfile
	infile="$1"
	outfile="$2"
fi

# test that infile provided
[ "$infile" = "" ] && errMsg "--- NO INPUT FILE SPECIFIED ---"

# test that outfile provided
[ "$outfile" = "" ] && errMsg "--- NO OUTPUT FILE SPECIFIED ---"

# test that colors_file provided
[ "$colors_file" = "" ] && errMsg "--- NO COLOR FILE SPECIFIED ---"


tmpA="$dir/mapcolors_$$.mpc"
tmpB="$dir/mapcolors_$$.cache"
tmp0="$dir/mapcolors_0_$$.miff"
tmp1="$dir/mapcolors_1_$$.miff"
tmp2="$dir/mapcolors_2_$$.miff"
trap "rm -f $tmpA $tmpB $tmp0 $tmp1 $tmp2;" 0
trap "rm -f $tmpA $tmpB $tmp0 $tmp1 $tmp2; exit 1" 1 2 3 15
trap "rm -f $tmpA $tmpB $tmp0 $tmp1 $tmp2; exit 1" ERR


# test input image
if convert -quiet "$infile" +repage "$tmpA"
	then
	: 'do nothing special'
	else
		errMsg "--- FILE $infile DOES NOT EXIST OR IS NOT AN ORDINARY FILE, NOT READABLE OR HAS ZERO SIZE ---"
fi

# set up depth
if [ "$depth" = "" ]; then
	bitdepth=""
else
	bitdepth="-depth $depth"
fi

# setup alpha for output
if [ "$alpha" = "off" ]; then
	transparent="-alpha off"
elif [ "$alpha" = "" ]; then
	transparent=""
fi


# setup type/class for output
if [ "$type" = "palette" ]; then
	otype="-type palette"
elif [ "$type" = "palettematte" ]; then
	otype="-type palettematte"
elif [ "$type" = "" ]; then
	otype=""
fi


#create transparent background image
ww=`convert $tmpA -ping -format "%w" info:`
hh=`convert $tmpA -ping -format "%h" info:`
convert -size ${ww}x${hh} xc:none $tmp0


echo ""
# put the file with line breaks into list, filter and then array
color_list=`cat $colors_file`
# first pattern changes all multiple spaces to one space
# second pattern removes leading space
# third pattern changes all "commma space" to just a comma
# fourth pattern changes spaces to colons so that cut can separate later
color_list=`echo "$color_list" | sed 's/[ ][ ]*/ /g;  s/^[ ]\(.*\)$/\1/;  s/[,][ ]/,/g;  s/ /:/g'`
colorArray=($color_list)
[ "$monitor" = "on" ] && echo "Total Colors To Map: ${#colorArray[*]}"
i=0
for colorpair in ${colorArray[*]}; do
	color1=`echo "$colorpair" | cut -d: -f1`
	color2=`echo "$colorpair" | cut -d: -f2`
	[ "$monitor" = "on" ] && echo "$i: $color1 to $color2"
	if [ "$safecolor" = "none" ]; then
		convert \( $tmpA -channel rgba -alpha on \
			-fill none +opaque "$color1" \
			-fill "$color2" -opaque "$color1" \) $tmp0 \
			-composite $tmp0
	else
		convert $tmpA -channel rgba -alpha on \
			-fill $safecolor +opaque "$color1" \
			-fill "$color2" -opaque "$color1" $tmp1
		convert $tmp1 \
			-fill black -opaque "$safecolor" \
			-fill white +opaque "$safecolor" $tmp2
		convert $tmp0 $tmp1 $tmp2 -composite $tmp0
	fi
	i=`expr $i + 1`
done
if [ "$safecolor" = "none" ]; then
	convert $tmpA $tmp0 -composite $bitdepth $transparent $otype "$outfile"
else
	convert $tmp0 -fill black -opaque "$safecolor" \
		-fill white +opaque "$safecolor" $tmp2
	convert $tmpA $tmp0 $tmp2 -composite $bitdepth $transparent $otype "$outfile"
fi
echo ""
exit 0