#!/bin/bash
######################################################################
#
#   svg_checkModelAbsref.sh -- This function retrieves absolute pahts
#   from source files and checks their existence.
#
#   In order for design templates to point different artistic motifs,
#   design templates make use of external files which point to
#   specific artistic motif background images. If such external files
#   don't exist, try to create the background image required by
#   cropping a higher background image (e.g., 2048x1536.png).  If this
#   isn't possible either, then create the background image using a
#   plain color and crop from it then.  We can't go on without the
#   required background information.
#
#   Written by:
#   * Alain Reguera Delgado <al@centos.org.cu>, 2009-2013
#
# Copyright (C) 2009-2013 The CentOS Artwork SIG
#
# 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.
#
######################################################################

function svg_checkModelAbsref {

    local FILE=''
    local BG_DST_FILES=''
    local BG_DST_FILE=''
    local BG_DST_FILE_WIDTH=''
    local BG_DST_FILE_HEIGHT=''
    local BG_SRC_FILE=''
    local BG_SRC_FILE_COLOR=''
    local BG_SRC_FILE_WIDTH=''
    local BG_SRC_FILE_HEIGHT=''

    # Define absolute path to the translated instance of design model.
    FILE="${1}"

    # Verify existence of file we need to retrieve absolute paths from.
    tcar_checkFiles -ef "${FILE}"

    # Retrieve absolute paths from file.
    BG_DST_FILES=$(egrep "(sodipodi:absref|xlink:href)=\"${HOME}.+" ${FILE} \
        | sed -r "s,.+=\"(${HOME}.+\.png)\".*,\1," | sort | uniq)

    # Verify absolute paths retrieved from file.
    for BG_DST_FILE in ${BG_DST_FILES};do

        # Verify parent directory of absolute files retrieved from
        # file. This is required to prevent the construction of paths
        # to locations that don't exist. For example, when including
        # background images in SVG files, it is possible that the path
        # information inside SVG files get outdated temporally. If in
        # that exact moment, you try to render the SVG file it won't
        # be possible to create the image used for cropping because
        # the path build from the location inside SVG file doesn't
        # exist. In this case, centos-art.sh script will end up with
        # `file ... doesn't exist' errors.
        tcar_checkFiles -d "$(dirname ${BG_DST_FILE})"

        if [[ ! -a ${BG_DST_FILE} ]];then
  
            # Define the source background file, the image file will
            # crop when no specific background information be
            # available for using. Generally, this is the most
            # reusable background file inside the artistic motifs
            # (e.g,.  the `2048x1536.png' file).  We can use this
            # image file to create almost all artworks inside The
            # CentOS Distribution visual manifestation when
            # resolution-specific backgrounds don't exist. 
            BG_SRC_FILE=$(echo ${BG_DST_FILE} \
                | sed -r "s!(.+)/[[:digit:]]+x[[:digit:]]+!\1/2048x1536!")

            # Verify existence of source background file. If the file
            # doesn't exist create it using The CentOS Project default
            # background color information, as specified in its
            # corporate identity manual.
            if [[ ! -f ${BG_SRC_FILE} ]];then

                # Define plain color that will be used as background.
                BG_SRC_FILE_COLOR='#204C8D'

                # Define width for the source background file the
                # required background information is cropped from.
                BG_SRC_FILE_WIDTH=$(echo ${BG_SRC_FILE} \
                    | sed -r 's!.+/([[:digit:]]+)x[[:digit:]]+\.png!\1!')

                # Define height for the source background file the
                # required background information is cropped from.
                BG_SRC_FILE_HEIGHT=$(echo ${BG_SRC_FILE} \
                    | sed -r 's!.+/[[:digit:]]+x([[:digit:]]+)\.png!\1!')

                # Print action message.
                tcar_printMessage "${BG_SRC_FILE} (${BG_SRC_FILE_COLOR})" --as-creating-line

                # Create the source background file.
                ppmmake -quiet ${BG_SRC_FILE_COLOR} \
                    ${BG_SRC_FILE_WIDTH} ${BG_SRC_FILE_HEIGHT} \
                    | pnmtopng > ${BG_SRC_FILE}

            fi

            # Define the width of the required background information.
            BG_DST_FILE_WIDTH=$(echo ${BG_DST_FILE} \
                | sed -r 's!.+/([[:digit:]]+)x[[:digit:]]+\.png!\1!')

            # Define the height of the required background information.
            BG_DST_FILE_HEIGHT=$(echo ${BG_DST_FILE} \
                | sed -r 's!.+/[[:digit:]]+x([[:digit:]]+)\.png!\1!')

            # Print action message.
            tcar_printMessage "${BG_SRC_FILE} (${BG_DST_FILE_WIDTH}x${BG_DST_FILE_HEIGHT})" --as-cropping-line
 
            # Create required background information.
            convert -quiet \
                -crop ${BG_DST_FILE_WIDTH}x${BG_DST_FILE_HEIGHT}+0+0 \
                ${BG_SRC_FILE} ${BG_DST_FILE}

            # Verify required background information.
            tcar_checkFiles -ef ${BG_DST_FILE}

        fi

    done

}