#!/bin/bash
version=1.7

# Set debug to 1 or greater to see the debugging output
# Alternatively, add the option '--debug'
debug=0


# Below is an example of how you should NOT write scripts.

# Will use either wget or lynx, whatever is available.
WGET="`which wget`"
if [ "$WGET" != "" ]; then
   WGETOPTS="-q -nv -O -"
 else
   WGET="`which lynx`"
   if [ "$WGET" != "" ]; then
     WGETOPTS="-source"
   else
     echo "
bibget may use either `wget' or `lynx' as its back-end, but neither seems unavailable.
Please make sure either `wget' or `lynx' are in the search path.
"
    exit 1
  fi
fi

[ "$debug" -ge 1 ] && echo WGET=$WGET
[ "$debug" -ge 1 ] && echo WGETOPTS=$WGETOPTS

mirror0=www.ams.org
mirror1=ams.rice.edu
mirror2=ams.impa.br
mirror3=ams.math.uni-bielefeld.de
mirror4=ams.mpim-bonn.mpg.de
mirror5=ams.u-strasbg.fr

mathscisite=$mirror0

tmpfile="/tmp/bibget.$(date +%N).tmp"

bibinputs=""

if [ "$BIBINPUTS" != "" ]; then
  for i in `echo $BIBINPUTS |sed 's/:/ /'`; do
    bibinputs="`echo $i|grep $HOME|sed 's/[/]*$//'`"
    [ "$bibinputs" != "" ] && break 
  done
fi

if [ "$2" = "" -a "$1" = "-m" -o "$1" = "-l" -o "$1" = "--list" ]; then
  echo "
Some available MathSciNet mirrors:

$mirror0
$mirror1
$mirror2
$mirror3
$mirror4
$mirror5

Default is $mathscisite

Use with the \`-m' option:  bibget -m $mirror1 ...
"
echo "Also checking  http://www.ams.org/errors/msn-mirrors.html for more..."
$WGET $WGETOPTS http://www.ams.org/errors/msn-mirrors.html|grep http | grep mathscinet\
  | sed 's/^.*http...//; s/.mathscinet.*//'
exit 0
fi

usage () {
echo "bibget, version $version: Command-line front-end for MathSciNet index.

GENERAL SEARCH:  bibget [[k=]keyword] [a=author] [t=title] [j=journal]
 
  EXAMPLES:  bibget a=gilkey t=invariance book 1984
             bibget r=MR783634 >> book.bib

OTHER OPTIONS:
  bibget [-m mirror | --mirror mirror] use alternative MathSciNet mirror
  bibget [-d|--debug] [other options]  debugging

OTHER USAGE:
  bibget [r=MRnumber | -r MRnumber]    grab a reference with given MRnumber
  bibget [-m | -l | --list]            list of some MathSciNet mirrors
  bibget [-h | --help ]                this help

EXAMPLE OF SSH TUNNELING (via the institution subscribed to MathSciNet):
  ssh -fN -L 31415:www.ams.org:80 math.tamu.edu
  bibget -m localhost:31415 a=gilkey t=invariance book 1984

          N.B. The options of SSH (see the ssh's man page): 
          fork into the background (-f) with no remote command (-N);
          forward local port 31415 to www.ams.org:80 via math.tamu.edu

  (C) Andrew Comech, 2008.  GNU General Public License.
"
}

if [ "$1" = "" -o "$1" = "-h" -o "$1" = "--help" ]; then
  usage;
  exit 0
fi


filter () {
    sed 's/.refmr.*.endrefmr//; s/^.*endrefmr//' | sed 's/;[ ].*.refmr.*$//; s/.refmr.*$//' | grep -v "MRNUMBER.="
}

input0="^$1^$2^$3^$4^$5^$6^$7^$8^$9^"

[ "$debug" -ge 1 ] && echo input0=$input0

input=`echo $input0 | sed 's/\^--debug//g;s/\^-d//g;s/--debug\^//g;s/-d\^//g'`

if [ "$input0" != "$input" ]; then
  debug=1
fi

[ "$debug" -ge 1 ] && echo input0=$input0

[ "$debug" -ge 1 ] && echo WGET=$WGET, WGETOPTS=\"$WGETOPTS\"

[ "$debug" -ge 1 ] && echo input1=$input

input=`echo $input|sed 's/-m\^/m=/g;s/--mirror\^/m=/g;s/-r\^/r=/g;s/-k\^/k=/g;s/-j\^/j=/g;s/-a\^/a=/g;s/-t\^/t=/g'`

[ "$debug" -ge 1 ] && echo corrected input1="$input"

suggestedmirror=`echo $input|sed 's/^.*\^m=//'|cut -f1 -d'^'`

[ "$debug" -ge 1 ] && echo suggestedmirror="$suggestedmirror"

if [ "$suggestedmirror" != "" ]; then
  mathscisite="$suggestedmirror"
fi

input=`echo $input|sed 's/\^m=[^\^]*\^/^/g'`

input="`echo $input|sed 's/[\^]*$//'`"

[ "$debug" -ge 1 ] && echo input2=$input

fish="`echo $input|cut -d'_' -f1| sed 's/, /,%20/; s/,%20./&'*'/'`"

output=""
if [ "`echo $input|grep '._.'`" != "" ]; then
  output="`echo $input|sed 's/$/.bib/; s/\.bib\.bib/.bib/'|cut -d'_' -f2`"
fi

fish="`echo $fish|sed 's/\^/^k=/g'`"

[ "$debug" -ge 1 ] && echo fish0=$fish

fish="`echo $fish|sed 's/\^k=a=/\&pg\^AUCN\&s\^/g' |sed 's/\^k=t=/\&pg\^TI\&s\^/g'|\
   sed 's/\^k=k=/\&pg\^ALLF\&s\^/g'|sed 's/\^k=r=/\&pg\^MR\&s\^/g'|sed 's/\^k=j=/\&pg\^JOUR\&s\^/g'|sed 's/\^k=/\&pg\^ALLF\&s\^/g' `"

[ "$debug" -ge 1 ] && echo fish1=$fish

fish="`echo $fish|sed 's/^\^//'`"


for i in 1 2 3 4 5 6 7 8 9; do 
  fish="`echo $fish | sed "s/\^/$i=/" | sed "s/\^/$i=/"`"
done

fish="$fish&extend=1"

[ "$debug" -ge 1 ] && echo fish2=$fish

prefix="$mathscisite"/msnmain?fn=130\&fmt=bibtex\&l=100
[ "$debug" -ge 1 ] && echo prefix=$prefix

if [ "$debug" -ge 1 ]; then 
  echo "Trying the following command:"
  echo $WGET $WGETOPTS http://"$prefix""$fish"|sed 's/&/\\&/g'
  echo " * * * Debugging mode (debug=$debug); will not filter the output! * * *"
  $WGET $WGETOPTS http://"$prefix""$fish" 
else
  $WGET $WGETOPTS http://"$prefix""$fish" | sed '1,/<pre>/d; /<\/pre>/,/<pre>/d; /<\/pre>/,$ d'
fi

exit