#!/bin/sh
# Thomas Esser, David Aspinall, Simon Wilkinson, 1998, 1999, 2002.
# Public domain.
#
# Simple script to attempt to find documentation for tex files.
# Uses kpsewhich to find a .dvi, .pdf or .ps file along the
# 'TeX system documentation' ($TEXDOCS, default: $TEXMF/doc) search path.
#
# Original version by David Aspinall <da@dcs.ed.ac.uk>
#
# This version rewritten for use with bash 2 and teTeX under Linux by
# Simon Wilkinson <sxw@dcs.ed.ac.uk>
#
# Changes for web2c-7.2 resp. teTeX-0.9 and portability fixes by
# Thomas Esser <te@dbs.uni-hannover.de>, Jun 14 1998

test -f /bin/sh5 && test -z "$RUNNING_SH5" \
  && { UNAMES=`uname -s`; test "x$UNAMES" = xULTRIX; } 2>/dev/null \
  && { RUNNING_SH5=true; export RUNNING_SH5; exec /bin/sh5 $0 ${1+"$@"}; }
unset RUNNING_SH5

test -f /bin/bsh && test -z "$RUNNING_BSH" \
  && { UNAMES=`uname -s`; test "x$UNAMES" = xAIX; } 2>/dev/null \
  && { RUNNING_BSH=true; export RUNNING_BSH; exec /bin/bsh $0 ${1+"$@"}; }
unset RUNNING_BSH

# Viewing programs, according to filename extension.  (You can
# override or add to them by setting environment variables).
: ${TEXDOCVIEW_dvi='(xdvi %s ) &'}
: ${TEXDOCVIEW_pdf='(acroread %s ) &'}
: ${TEXDOCVIEW_ps='(gv %s ) &'}
: ${TEXDOCVIEW_html='(netscape -remote openURL'"'(%s)'"' 2>/dev/null || netscape %s) &'}
: ${TEXDOCVIEW_txt="${PAGER-less} %s"}
: ${TEXDOCVIEW_="${PAGER-less} %s"} # no extension, default to pager

# Commands run to uncompress files, according to filename extension.
: ${TEXDOCUNZIP_gz='gzip -d -c'}
: ${TEXDOCUNZIP_bz2='bzip2 -d -c'}
: ${TEXDOCUNZIP_zip='unzip -p'}
: ${TEXDOCUNZIP_Z='uncompress -d -c'}

mode=viewer
help='Usage: texdoc [OPTION]... [NAME]...
  Search for NAME in the TeX documentation and start a viewer.

  --help        show this help
  -v		verbose mode: show viewer command
  -l            just list all matching files. Do not start a viewer.
  -s            search the disk. remaining arguments will be passed
                as egrep patterns to filter the find output.'

verbosemode=false
while 
  case $1 in
     -s)     mode=search; shift; break;;
     -l)     mode=list;;
     -v)     verbosemode=true;;
     *-help)
             echo "$help" >&2
             exit 1;;
     -*)     echo "texdoc: option $1 not recognized" 1>&2;;
      *)     break;;
  esac
do shift; done

case $# in
  0)
    echo "$help" >&2
    exit 1
    ;;
esac

tmpdir=${TMPDIR-/tmp}/texdoc$$.$RANDOM
mkdir -m 0700 $tmpdir || exit 1
trap 'rm -rf  $tmpdir/; exit 1' 1 2 6 13 15
clean='rmdir  $tmpdir/ 2>/dev/null'
TMPDIR=$tmpdir; export TMPDIR

listext="`kpsewhich --expand-brace='$TEXDOCEXT' 2>/dev/null`"
test -z "$listext" && listext=":"

for name
do
  case $mode in
    search)
      find `kpsewhich --expand-path='$TEXMF/doc' | tr : ' '` -type f -print |
        egrep $name
      continue
      ;;
  esac

  case $name in
    texdoc)
      man texdoc; continue;;
  esac

  found=false
  OIFS=$IFS
  IFS=':'
  for ext in $listext; do

    filename=`kpsewhich -format='TeX system documentation' $name$ext 2>/dev/null`
    test -z "$filename" && continue
    found=true

    if test $mode = list; then
      echo $filename
    else
      dir=`echo $filename | sed 's%/[^/]*$%%'`
      ext=`echo $filename | sed -n 's%.*\.\([^/]*\)$%\1%p'`
      eval uncompress="\$TEXDOCUNZIP_$ext"
      if test -n "$uncompress"
      then
	ext=`echo $filename | sed -e "s|\\.$ext\$||" | sed 's%.*\.%%'`
      fi
      viewer=\$"TEXDOCVIEW_$ext"
      if test -n "$uncompress"
      then
	src=`echo "$filename" | sed -e 's%.*/%%' -e 's%\.[^.]*$%%'`
	eval "$uncompress $filename > $tmpdir/$src"
	filename=$tmpdir/$src
	viewer=`eval echo $viewer | sed -e "s|%s|$filename;rm -f $filename;$clean|g"`
      else
	viewer=`eval echo $viewer | sed -e "s|%s|$filename;$clean|g"`
      fi
      if test -z "$viewer"
      then
        echo "Don't know how to view file type $ext" 1>&2
        echo "(matching file was $filename)" 1>&2
      else
        $verbosemode && echo $viewer
        dir=`echo "$filename" | sed 's%/[^/]*$%%'`
        test -n "$dir" && test -d "$dir" && cd "$dir"
        eval $viewer
        break     # just stop after the first usable extension
      fi
    fi

  done
  $found || echo "Can't find documentation for \`$name'" 1>&2
  IFS=$OIFS
done
sleep 2
eval $clean
exit 0
