#!/bin/sh

#
# pandoc-post - clean up pandoc outputs, depending on format and
#               version
#
SED=/bin/sed
XMLLINT=/usr/bin/xmllint
XMLLINT_FLAGS=--nonet
#
scriptname=pandoc-post
if ! MYTMP=$(mktemp -d -t $scriptname-XXXXXX)
then
            echo >&2
            echo >&2
            echo >&2 "Cannot create temporary directory."
            echo >&2
            exit 1
fi

cleanup() {
  status=$?
  rm -rf "${MYTMP}"
  exit $status
}

# clean up if we get stopped by Crtl-C or forced logout or normal exit
trap cleanup INT
trap cleanup HUP
trap cleanup 0

split()
{
    # Prefix local names with the function name to try to avoid conflicts
    # local split_wordlist
    split_wordlist="$1"
    shift
    read "$@" <<EOF-split-end-of-arguments
${split_wordlist}
EOF-split-end-of-arguments
}

# Usage: version_ge v1 v2
# Where v1 and v2 are multi-part version numbers such as 12.5.67
# Missing .<number>s on the end of a version are treated as .0, & leading
# zeros are not significant, so 1.2 == 1.2.0 == 1.2.0.0 == 01.2 == 1.02
# Returns true if v1 >= v2, false if v1 < v2
version_ge()
{
    # Prefix local names with the function name to try to avoid conflicts
    # local version_ge_1 version_ge_2 version_ge_a version_ge_b
    # local version_ge_save_ifs
    version_ge_v1="$1"
    version_ge_v2="$2"

    version_ge_save_ifs="$IFS"
    while test -n "${version_ge_v1}${version_ge_v2}"; do
        IFS="."
        split "$version_ge_v1" version_ge_a version_ge_v1
        split "$version_ge_v2" version_ge_b version_ge_v2
        IFS="$version_ge_save_ifs"
        #echo " compare  $version_ge_a  $version_ge_b"
        test "0$version_ge_a" -gt "0$version_ge_b" && return 0 # v1>v2: true
        test "0$version_ge_a" -lt "0$version_ge_b" && return 1 # v1<v2:false
    done
    # version strings are both empty & no differences found - must be equal.
    return 0 # v1==v2: true
}

if [ $# -ne 3 ]
then
  echo "Usage: pandoc-post pandoc-version file-format filename"
  echo "       cleans up pandoc output by version and format"
  exit 1
fi

version="$1"
shift
format="$1"
shift
filename="$1"
shift

if [ ! -f "$filename" ]
then
  echo "No such file: $filename"
  exit 1
fi

if ! version_ge "$version" 1.9.4.2
then
  echo "Only versions of pandoc >= 1.9.4.2 are catered for"
  exit 1
fi

case "$format" in
      pdf)
        # No cleanup we can do
        exit 0
      ;;

      html)
        # Validate tags
	$XMLLINT $XMLLINT_FLAGS --html "$filename" > $MYTMP/verify.html

        # Reformat so we can indentify internal  sections
	$XMLLINT $XMLLINT_FLAGS --format "$filename" > $MYTMP/format.html

        # Fixup some whitespace formatting damage done by xmllint
        # - if line ends in a pre
        #   N = join next line, then remove newline and finally excess spaces
        $SED -i -e '/<pre>$/{N;s/\n//;s/<pre> *<code>/<pre><code>/}' \
                -e '/<\/code>$/{N;s/\n//;s:</code> *</pre>:</code></pre>:}' \
             $MYTMP/format.html
        # Remove manpage internal sections from HTML (several levels down)
	$SED -e '/^                  <ul>/,/^                  <\/ul>/d' $MYTMP/format.html > "$filename"
        :
      ;;

      man)
        :
        # Disable groff hyphenation (wrecks URLs)
	$SED -i -e '1a.nh' "$filename"
        if version_ge "$version" 1.9.4.2
        then
          # supress any internal links, since pandoc just leaves them
          # verbatim in manpage output
	  $SED -i -e 's/ (#[a-z.0-9_-]*)//g' "$filename"
        fi
      ;;

      *)
        echo "Unknown format $format"
      ;;
esac

exit 0
