#--------------------------------
#
sub parsecheck {
 
($frmt, $start, $end, $ra, $dec, $freeform) = @_;
 
@MESSAGE = ('<center>Please enter RA as <font color="#ff0000"> hh:mm:ss.ss</font></center>',
            '<center>Please enter DEC as <font color="#ff0000"> (-)dd:mm:ss.ss</font></center>',
            '<center>Please enter start date as <font color="#ff0000"> mm/dd/yyyy</font></center>',
            '<center>Please enter end date as <font color="#ff0000"> mm/dd/yyyy</font></center>',
);
 
# parse
if ($frmt eq 'fixed') {
  if ($ra && $dec && $start) {
    $end = $start if ($end eq '');
  }
 
  push @starts, $start;
  push @ends, $end;
  push @ras, $ra;
  push @decs, $dec;
 
} elsif ($frmt eq 'free') {
 
  # extract the "lines" from the input
  @lines = split /\n/, $freeform;
 
  # loop on the lines and see what we got
  foreach $i (0 .. $#lines) {
 
    ($ra,$dec,$start,$end) = split / /, &trim($lines[$i]), 4;
 
    if ($ra && $dec && $start) {
      $end = $start if ($end eq '');
    }
 
    push @starts, $start;
    push @ends, $end;
    push @ras, $ra;
    push @decs, $dec;
 
  }
} else {
  $errmsg = '';
  return ('<center>Please complete the form and submit using the <strong>Calculate</strong> button.</center>');
}
 
# look for any error and quit at the first sight
foreach $i (0 .. $#starts) {
  $errmsg = '';
  $errmsg = $errmsg.$MESSAGE[0] if ($ras[$i] !~ /[0-9]+:[0-9]+/);
  $errmsg = $errmsg.$MESSAGE[1] if ($decs[$i] !~ /[0-9]+:[0-9]+/);
  $errmsg = $errmsg.$MESSAGE[2] if ($starts[$i] !~ /[0-9]{2}\/[0-9]{2}\/[0-9]{4}/);
  $errmsg = $errmsg.$MESSAGE[3] if ($ends[$i] !~ /[0-9]{2}\/[0-9]{2}\/[0-9]{4}/);
  if ($errmsg) {
    $errmsg =  "<center><br><font size=4>Warning!</font><font color=#ff0000>$errmsg</font> <br>Please use your browser'
s back button to revise your input and then submit your request again.<br>For assistance please contact: <a href=\"mail
to:help\@stsci.edu\">help\@stsci.edu</a>.</center>";
    last;
  }
 
}
 
return ($errmsg, \@starts, \@ends, \@ras, \@decs);
 
}