#!/bin/bash

# fcw2pdf.sh: a simple fcw to PDF converter script.
# Copyright 2017 Christopher Spinrath <christopher.spinrath@tu-dortmund.de>

# fcw2pdf.sh 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 3 of the License, or
# (at your option) any later version.

# fcw2pdf.sh 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 fcw2pdf.sh.  If not, see <http://www.gnu.org/licenses/>.

set -e

INPUT_FILE=$1

if [ "x$1" == "x" ]; then
  echo "Usage: fcw2pdf.sh <input.fcw> [<output.pdf>]"
  exit 1
fi

INPUT_BASENAME="$(basename "$INPUT_FILE" ".fcw")"
shift

OUTPUT_FILE=${1:-"${INPUT_BASENAME}.pdf"}

WORKDIR="$(mktemp -d)"
function cleanup {
	rm -Rf "$WORKDIR"
}
trap cleanup EXIT

cp "$INPUT_FILE" "$WORKDIR/in.zip"
pushd "$WORKDIR" > /dev/null
unzip "in.zip" > /dev/null

#We could just go with $(ls *.svg) but then the files may be in the wrong order.
#Hence, let's look up the files in the correct order in the manifest file.
MANIFEST_FILE=imsmanifest.xml
PAGE_FILE_QUERY='//resources/resource[@identifier="pages"]/file/@href'
PAGE_FILE_QUERY_RES=$(xmllint --html --xpath "$PAGE_FILE_QUERY" "$MANIFEST_FILE" 2> /dev/null)

#xmllint's return format is crap; clean it up
PAGE_FILES=$(echo "$PAGE_FILE_QUERY_RES" | tr "[:space:]" "\n" | cut -d\" -f2 | grep -v '^$')

PDF_FILES=""
for PAGE_FILE in $PAGE_FILES; do
	PAGE_BASENAME="$(basename "$PAGE_FILE" ".svg")"
	PAGE_PDF="$PAGE_BASENAME.pdf"
    PDF_FILES="$PDF_FILES $PAGE_PDF"
	echo "Converting $PAGE_BASENAME"
	#convert -density 90 -define pdf:fit-page=A4 "$PAGE_FILE" "$PAGE_PDF"
    #pass input via stdin, otherwise cairosvg seems to be unable to open included image files
	cairosvg -o "$PAGE_PDF" -  < "$PAGE_FILE"
done

pdfunite $PDF_FILES out.pdf

popd > /dev/null
cp "$WORKDIR/out.pdf" "$OUTPUT_FILE"