#!/bin/bash

#

# identity_renderSyslinux.sh -- This function provides post-rendition

# action used to produce syslinux images.

#

# 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307

# USA.

# 

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

# $Id$

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

function identity_renderSyslinux {

    # Define 16 colors images default file name prefix.

    local PREFIX='-16c'

    # Define options using those passed to actions from pre-rendition

    # configuration script. These options are applied to pnmremap when

    # doing color reduction, so any option available for pnmremap

    # command can be passed to renderSyslinux functionality.

    local OPTIONS=$(identity_getConfigOption "$ACTION" '2-')

    # Check options passed to action. This is required in order to

    # aviod using options used already in this script. For example

    # -verbose and -mapfile options.

    for OPTION in $OPTIONS;do

        # Remove anything after equal sign inside option.

        OPTION=$(echo $OPTION | cut -d'=' -f1)

        if [[ "$OPTION" =~ "-(mapfile|verbose)" ]];then

            cli_printMessage "`eval_gettext "The \\\$OPTION option is already used."`"

            cli_printMessage "$(caller)" "AsToKnowMoreLine"

        fi

    done

    # Re-define 16 colors images default file name prefix using

    # options as reference. This is useful to differenciate final

    # files produced using Floyd-Steinberg dithering and final files

    # which are not.

    if [[ "$OPTIONS" =~ '-floyd' ]];then

        PREFIX="${PREFIX}-floyd"

    fi

    # Define motif's palette location.

    local PALETTES=$(cli_getRepoTLDir)/Identity/Themes/Motifs/$(cli_getPathComponent '--theme')/Colors

    # Define the Netpbm color palette used when reducing colors. This

    # palette should be 16 colors based. For more information on this

    # see the isolinux documentation.

    local PALETTE_PPM=$PALETTES/syslinux.ppm

    # Define hexadecimal color information used by ppmtolss16.  Color

    # information and order used on PALETTE_HEX and PALETTE_PPM should

    # match exactly.

    local PALETTE_HEX=$PALETTES/syslinux.hex

    # Print which palette of colors centos-art.sh script is using to

    # produce grub content. This is relevant in order to know if we

    # are using whether trunk or branches palette of colors.

    cli_printMessage "$PALETTE_PPM" 'AsPaletteLine'

    cli_printMessage "$PALETTE_HEX" 'AsPaletteLine'

    # Check syslinux's palettes existence:  If there is no palette

    # assume that this is the first time you are rendition syslinux

    # images. If that is the case the script will provide you with the

    # PNG format which should be used as base to produce (using GIMP)

    # the .gpl palette.  The .gpl palette information is used to

    # produced (using GIMP) the colormap (.ppm) which is used to

    # automate the syslinux's 16 colors image (syslinux-splash.png)

    # rendition.  If there is no palette available, do not apply color

    # reduction, show a message, and continue.

    cli_checkFiles $PALETTE_PPM

    cli_checkFiles $PALETTE_HEX

    # Create Netpbm superformat (PNM). PNM file is created from the

    # PNG image rendered previously. PNM is a common point for image

    # manipulation using Netpbm tools.

    cli_printMessage "${FILE}.pnm" "AsSavedAsLine"

    pngtopnm -verbose \

        < ${FILE}.png 2>${FILE}.log > ${FILE}.pnm

    # Reduce colors. Here we use the Netpbm color $PALETTE_PPM to

    # enforce the color position in the image index and the

    # Floyd-Steinberg dithering in order to improve color reduction.

    cli_printMessage "${FILE}${PREFIX}.pnm" "AsSavedAsLine"

    pnmremap -verbose -mapfile=$PALETTE_PPM $OPTIONS \

        < ${FILE}.pnm 2>> ${FILE}.log > ${FILE}${PREFIX}.pnm

    # Create LSS16 image. As specified in isolinux documentation the

    # background color should be indexed on position 0 and forground

    # in position 7 (see /usr/share/doc/syslinux-X.XX/isolinux.doc).

    # This order of colors is specified in $PALETTE_PPM and redefined

    # here again for the LSS16 image format. Both $PALETTE_PPM and

    # LSS16 color map redefinition ($PALETTE_HEX) should have the same

    # colors and index order. PALETTE_HEX should return just one line

    # with the color information as described in isolinux

    # documentation (i.e #RRGGBB=0 #RRGGBB=1 ... [all values in the

    # same line]).

    cli_printMessage "${FILE}${PREFIX}.lss" "AsSavedAsLine"

    PALETTE_HEX=$(cat $PALETTE_HEX | tr "\n" ' ' | tr -s ' ')

    ppmtolss16 $PALETTE_HEX \

        < ${FILE}${PREFIX}.pnm 2>>${FILE}.log > ${FILE}${PREFIX}.lss

    # Create the PPM image indexed to 16 colors. Also the colormap

    # used in the LSS16 image is saved on ${FILE}.log; this is useful to

    # verify the correct order of colors in the image index.

    cli_printMessage "${FILE}${PREFIX}.ppm" "AsSavedAsLine"

    lss16toppm -map \

        < ${FILE}${PREFIX}.lss 2>>${FILE}.log > ${FILE}${PREFIX}.ppm

    # Create the 16 colors PNG image.

    cli_printMessage "${FILE}${PREFIX}.png" "AsSavedAsLine"

    pnmtopng -verbose -palette=$PALETTE_PPM \

        < ${FILE}${PREFIX}.pnm 2>>${FILE}.log > ${FILE}${PREFIX}.png

}