#!/bin/sh

# Runs LaTeX and converts its messages into GNU standard message format
#
# Copyright (C) 1999-2008 Frank Heckenbach <frank@g-n-u.de>
#
# 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, version 2.
#
# 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; see the file COPYING.  If not, write to
# the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
# MA 02111-1307, USA.

# This script requires bash. Since bash cannot be assumed to be in
# /bin, /usr/bin or any other certain place, we cannot use it in the
# first line. So we use /bin/sh, which can be assumed to exist. Then
# we check if it's actually bash, and if not, try to re-run the
# script with bash.
if [ x"$BASH" = x ]; then
  if [ x"$RERUN_BASH_TRIED" != x ]; then
    echo "`basename $0`: cannot run, \`bash' is either not bash or a very old version" >&2
    exit 1
  else
    RERUN_BASH_TRIED=1; export RERUN_BASH_TRIED
    exec bash $0 "$@"
    echo "`basename $0`: cannot run bash" >&2
    exit 1
  fi
fi
RERUN_BASH_TRIED=""

LATEXPREFIX=""; EXT=".dvi"
if [ x"$1" = x"-p" ]; then LATEXPREFIX="pdf"; EXT=".pdf"; shift; fi
if [ $# -ne 1 ]; then { echo "Usage: `basename $0` [-p] filename"; echo "Options:"; echo "  -p: use pdflatex instead of latex"; } >&2; exit 1; fi
AWK=gawk; "$AWK" --version > /dev/null 2>&1 || AWK=awk
BASENAME="`echo "$1" | sed -e "s,.*/,,;s/\.\(tex\|ltx\)$//"`"
rerun=1; while [ $rerun -gt 0 ]; do
  rm -f "$BASENAME$EXT"
  "$LATEXPREFIX${LATEX:-latex}" "\nonstopmode \input $1" 2>&1 | "$AWK" '
    BEGIN { skip = 0; msg == ""; fc = 0; fn = f[0] = ""; rerun = 0 }
          { gsub ("\\? *", "") }
    /[Rr]erun/ { rerun = 1 }
    /^</  { skip = 2 }
    /Transcript written/ || /^Type.*return/ || /^ *$/ || /^ *\.\.\. *$/ { skip = 1 }
    /^!/  { if (msg != "") print fn ": " msg; msg = $0; gsub ("^! *", "", msg); skip = 1 }
    msg != "" && /^l./ { sub ("^l.", ""); i = index ($0, " "); if (i == 0) i = 1; print fn ":" substr ($0, 1, i - 1) ":" length ($0) - i + 1 ": " msg; msg = ""; skip = 2 }
    msg != "" && !skip { sub ("^ *", ""); msg = msg " " $0 }
    msg == "" && !skip { print; while (gsub ("\\(.[^()]*\\)", ""));
                         while ((i = index ($0, ")"))) { if (fc) fn = f[--fc]; $0 = substr ($0, i + 1) }
                         while ((i = index ($0, "("))) { fn = f[++fc] = gensub ("^[^(]*\\(([^() ]*).*$", "\\1", "g", $0); $0 = substr ($0, i + 1) } }
    skip  { skip-- }
    END   { if (msg != "") print fn ": " msg; if (rerun) exit(1) }
  '
  status=${PIPESTATUS[0]} rerun=${PIPESTATUS[1]}
  rm -f "$BASENAME.log"
  if [ "$status" -eq 0 -a ! -f "$BASENAME$EXT" ]; then status=1; fi
  if [ "$status" -ne 0 ]; then exit "$status"; fi
done