#!/bin/bash

#

# render_convertGplToPpm.sh -- This function takes one palette

# produced by Gimp (e.g., syslinux.gpl) as input and outputs one PPM

# file based on it (e.g., syslinux.ppm).

#

# Copyright (C) 2009-2011 Alain Reguera Delgado

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or (at

# your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

# General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

# ----------------------------------------------------------------------

# $Id$

# ----------------------------------------------------------------------

function render_convertGplToPpm {

    local COLOR=''

    local COUNT=0

    local -a FILES

    # Define path to GPL palette. This is the .gpl file we use to

    # retrive color information from.

    local PALETTE_GPL="$1"

    # Define path to PPM palette. This is the .ppm file we'll save

    # color information to.

    local PALETTE_PPM="$2"

    # Define the number of colors this function should return.

    local COLOR_NUMBER="$3"

    # Verify the number of colors this function should return. As

    # convenction, we are producing images in 14 and 16 colors only to

    # cover Grub and Syslinux images need respectively.

    if [[ ! $COLOR_NUMBER =~ '^(14|16)$' ]];then

        cli_printMessage "`eval_gettext "Reducing image to \\\`\\\$COLOR_NUMBER' colors is not supported."`" 'AsErrorLine'

        cli_printMessage "${FUNCDIRNAM}" 'AsToKnowMoreLine'

    fi

    # Define list of colors from GPL palette.

    local COLORS=$(render_getColors "$PALETTE_GPL")

    # Verify number of colors returned in the list.

    if [[ ! $(echo "$COLORS" |  wc -l) =~ $COLOR_NUMBER ]];then

        cli_printMessage "`gettext "The palette doesn't have the correct number of colors."`" 'AsErrorLine'

        cli_printMessage "${FUNCDIRNAM}" 'AsToKnowMoreLine'

    fi

    # Verify format of colors inside the list.

    for COLOR in $COLORS;do

        if [[ ! $COLOR =~ '^[0-9a-f]{6}$' ]];then

            cli_printMessage "`eval_gettext "The \\\`\\\$COLOR' string isn't a valid color code."`" 'AsErrorLine'

            cli_printMessage "${FUNCDIRNAM}" 'AsToKnowMoreLine'

        fi

    done

    # Create temporal images (of 1x1 pixel each) for each color

    # retrived from Gimp's palette.

    for COLOR in $COLORS;do

        FILES[$COUNT]=$(cli_getTemporalFile "color-${COUNT}.ppm")

        ppmmake $(echo "$COLOR" \

            | sed -r 's!(.{2})(.{2})(.{2})!rgb:\1/\2/\3!') 1 1 \

            > ${FILES[$COUNT]}

        COUNT=$(($COUNT + 1))

    done

    # Concatenate temporal images from left to right to create the PPM

    # file.

    pnmcat -lr ${FILES[*]} > $PALETTE_PPM

    # Remove temporal images.

    rm ${FILES[*]}

    # Verify PPM palette existence.

    cli_checkFiles "$PALETTE_PPM" 'f'

}