#!/usr/bin/perl
# converts an evolver file to a v file
# Usage: evol2v [-d dimension] [evolverfile]
#   if no evolverfile specified, reads from stdin
#   option -d to give dimension if "SPACE_DIMENSION"
#     is not present in the file

# can handle "//" comments only for evolver input. however,
#       vertices  /* coordinates */
#       edges     /* something */
#   are both fine

# The first two integers of a v file are number of vertices
# and dimension, respectively.  After these two numbers,
# the vertices are listed.  Whitespace, newlines are irrelevant.
# Can deal with "#" comments.


$dim = 3 ;
if( @ARGV[0] =~ /^-d$/ ) {
    shift(@ARGV) ;
    $dim = shift(@ARGV) ;
}

while(<>) {
    @toks = get_line_tokens($_) ;
    $dim = $toks[1] if $toks[0] =~ /^SPACE_DIMENSION$/ ;
    last if $toks[0] =~ /^vertices$/ ;
}
$toks[0] =~ /^vertices$/ || die "can't find vertices.\n" ;
while(<>) {
    @toks = get_line_tokens($_) ;
    last if $toks[0] =~ /^edges$/ ;
    next if @toks == 0 ;                  #skip blank or comment line
    shift(@toks) ;                        #don't care about vertex number
    ++$nvert ;
    for( $i = 0 ; $i < $dim ; $i++ ) {
	$v[$nvert-1][$i] = shift(@toks) ;
    }
}
$toks[0] =~ /^edges$/ || die "can't find edges.\n" ;
print "$nvert $dim\n" ;
for( $i = 0 ; $i < $nvert ; $i++ ) {
    for( $j = 0 ; $j < $dim ; $j++ ) {
	print "$v[$i][$j] " ;
    }
    print "\n" ;
}

#ignores double-slash comments
sub get_line_tokens
{
    $line = $_[0] ;
    chomp($line) ;
    $line =~ s/^\s*// ;    #split fn doesn't ignore leading white. perl bug?
    if($line =~ /\/\//) {   #ignore after "//"
       return split(/\s+/, $`) ;
    }
    else {
        return split(/\s+/, $line) ;
    }
}