#!/usr/bin/perl

# perl program to take a thesaurus structured text data file 

# and create the proper sorted index file (.idx)

#

# typically invoked as follows:

# cat th_en_US_new.dat | ./th_gen_idx.pl > th_en_US_new.idx

#

sub by_entry {

    my ($aent, $aoff) = split('\|',$a);

    my ($bent, $boff) = split('\|',$b);

    $aent cmp $bent;

}

# main routine

my $ne = 0;       # number of entries in index

my @tindex=();    # the index itself

my $foffset = 0;  # file position offset into thesaurus

my $rec="";       # current string and related pieces

my $rl=0;         # misc string length     

my $entry="";     # current word being processed

my $nm=0;         # number of meaning for the current word

my $meaning="";   # current meaning and synonyms

my $p;            # misc uses

my $encoding;     # encoding used by text file

# top line of thesaurus provides encoding

$encoding=<STDIN>;

$foffset = $foffset + length($encoding); 

chomp($encoding);

# read thesaurus line by line

# first line of every block is an entry and meaning count

while ($rec=<STDIN>){

    $rl = length($rec);

    chomp($rec);

    ($entry, $nm) = split('\|',$rec);

    $p = 0;

    while ($p < $nm) {

        $meaning=<STDIN>;

        $rl = $rl + length($meaning);

        chomp($meaning);

        $p++;

    }       

    push(@tindex,"$entry|$foffset");

    $ne++;

    $foffset = $foffset + $rl;

}

# now we have all of the information

# so sort it and then output the encoding, count and index data

@tindex = sort by_entry @tindex;

print STDOUT "$encoding\n";

print STDOUT "$ne\n";

foreach $one (@tindex) {

    print STDOUT "$one\n";

}