--- /dev/null
+#
+# the dx spot handler
+#
+# Copyright (c) - 1998 Dirk Koopman G1TLH
+#
+# $Id$
+#
+
+package spot;
+
+use FileHandle;
+use DXVars;
+use DXDebug;
+use julian;
+
+@ISA = qw(julian);
+
+use strict;
+
+my $fp;
+my $maxdays = 60; # maximum no of days to store spots in the table
+my $prefix = "$main::data/spots";
+my @table = (); # the list of spots (held in reverse order)
+
+# read in n days worth of dx spots into memory
+sub init
+{
+ my @today = julian->unixtoj(time); # get the julian date now
+ my @first = julian->sub(@today, $maxdays); # get the date $maxdays ago
+ my $count;
+
+ mkdir($prefix, 0777) if ! -e $prefix; # create the base directory if required
+ for (my $i = 0; $i < $maxdays; ++$i) {
+ my $ref = spot->open(@first);
+ if ($ref) {
+ my $fh = $ref->{fh};
+ while (<$fh>) {
+ chomp;
+ my @ent = split /\^/;
+ unshift @spot::table, [ @ent ]; # stick this ref to anon list on the FRONT of the table
+ ++$count;
+ }
+ }
+ @first = julian->add(@first, 1);
+ }
+ return $count;
+}
+
+# create a new spot on the front of the list, add it to the data file
+sub new
+{
+ my $pkg = shift;
+ my @spot = @_; # $freq, $call, $t, $comment, $spotter = @_
+
+ # sure that the numeric things are numeric now (saves time later)
+ $spot[0] = 0 + $spot[0];
+ $spot[2] = 0 + $spot[2];
+
+ # save it on the front of the list
+ unshift @spot::table, [ @spot ];
+
+ # compare dates to see whether need to open a other save file
+ my @date = julian->unixtoj($spot[2]);
+ $fp = spot->open(@date, ">>") if (!$fp || julian->cmp(@date, $fp->{year}, $fp->{day}));
+ my $fh = $fp->{fh};
+ $fh->print(join("\^", @spot), "\n");
+}
+
+# purge all the spots older than $maxdays - this is fairly approximate
+# this should be done periodically from some cron task
+sub purge
+{
+ my $old = time - ($maxdays * 86400);
+ my $ref;
+
+ while (@spot::table) {
+ my $ref = pop @spot::table;
+ if (${$ref}[2] > $old) {
+ push @spot::table, $ref; # put it back
+ last; # and leave
+ }
+ }
+}
+
+# search the spot database for records based on the field no and an expression
+# this returns a set of references to the spots
+#
+# for string fields supply a pattern to match
+# for numeric fields supply a range of the format 'n > x && n < y' (the n will
+# changed to the correct field name) [ n is literally the letter 'n' ]
+#
+sub search
+{
+ my ($pkg, $field, $expr) = @_;
+ my $eval;
+ my @out;
+ my $ref;
+
+ dbg('spot', "input expr = $expr\n");
+ if ($field == 0 || $field == 2) { # numeric fields
+ $expr =~ s/n/\$ref->[$field]/g; # swap the letter n for the correct field name
+ } else {
+ $expr = qq(\$ref->[$field] =~ /$expr/oi); # alpha expressions
+ }
+ dbg('spot', "expr now = $expr\n");
+
+ # build up eval to execute
+ $eval = qq(foreach \$ref (\@spot::table) {
+ push \@out, \$ref if $expr;
+ });
+ dbg('spot', "eval = $eval\n");
+ eval $eval; # execute it
+ return @out;
+}
+
+# open a spot file of the julian day
+sub open
+{
+ my $pkg = shift;
+ return julian->open("spot", $prefix, @_);
+}
+
+# close a spot file
+sub close
+{
+ # do nothing, unreferencing or overwriting the $self will close it
+}
+
+1;