+#
+# 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 $maxspots = 50; # maximum spots to return
+my $defaultspots = 10; # normal number of spots to return
+my $maxdays = 35; # normal maximum no of days to go back
+my $prefix = "$main::data/spots";
+
+# add a spot to the data file (call as Spot::add)
+sub add
+{
+ 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];
+
+ # compare dates to see whether need to open another save file (remember, redefining $fp
+ # automagically closes the output file (if any))
+ my @date = Julian::unixtoj($spot[2]);
+ $fp = Spot->open(@date, ">>") if (!$fp || Julian::cmp(@date, $fp->{year}, $fp->{day}));
+
+ # save it
+ my $fh = $fp->{fh};
+ $fh->print(join("\^", @spot), "\n");
+}
+
+# search the spot database for records based on the field no and an expression
+# this returns a set of references to the spots
+#
+# the expression is a legal perl 'if' statement with the possible fields indicated
+# by $f<n> where :-
+#
+# $f0 = frequency
+# $f1 = call
+# $f2 = date in unix format
+# $f3 = comment
+# $f4 = spotter
+#
+# In addition you can specify a range of days, this means that it will start searching
+# from <n> days less than today to <m> days less than today
+#
+# Also you can select a range of entries so normally you would get the 0th (latest) entry
+# back to the 5th latest, you can specify a range from the <x>th to the <y>the oldest.
+#
+# This routine is designed to be called as Spot::search(..)
+#
+
+sub search
+{
+ my ($expr, $dayfrom, $dayto, $from, $to) = @_;
+ my $eval;
+ my @out;
+ my $ref;
+ my $i;
+ my $count;
+ my @today = Julian::unixtoj(time);
+ my @fromdate;
+ my @todate;
+
+ if ($dayfrom > 0) {
+ @fromdate = Julian::sub(@today, $dayfrom);
+ } else {
+ @fromdate = @today;
+ $dayfrom = 0;
+ }
+ if ($dayto > 0) {
+ @todate = Julian::sub(@fromdate, $dayto);
+ } else {
+ @todate = Julian::sub(@fromdate, $maxdays);
+ }
+ if ($from || $to) {
+ $to = $from + $maxspots if $to - $from > $maxspots || $to - $from <= 0;
+ } else {
+ $from = 0;
+ $to = $defaultspots;
+ }
+
+ $expr =~ s/\$f(\d)/zzzref->[$1]/g; # swap the letter n for the correct field name
+ $expr =~ s/[\@\$\%\{\}]//g; # remove any other funny characters
+ $expr =~ s/\&\w+\(//g; # remove subroutine calls
+ $expr =~ s/eval//g; # remove eval words
+ $expr =~ s/zzzref/\$ref/g; # put back the $ref
+ $expr =~ s|(/.+/)|$1oi|g; # add oi characters to /ccc/
+
+ print "expr=($expr), from=$from, to=$to\n";
+
+ # build up eval to execute
+ $eval = qq(my \$c;
+ for (\$c = \$#spots; \$c >= 0; \$c--) {
+ \$ref = \$spots[\$c];
+ if ($expr) {
+ \$count++;
+ next if \$count < \$from; # wait until from
+ push(\@out, \$ref);
+ last LOOP if \$count >= \$to; # stop after to
+ }
+ });
+
+LOOP:
+ for ($i = 0; $i < 60; ++$i) {
+ my @now = Julian::sub(@fromdate, $i);
+ last if Julian::cmp(@now, @todate) <= 0;
+
+ my @spots = ();
+ my $fp = Spot->open(@now); # get the next file
+ if ($fp) {
+ my $fh = $fp->{fh};
+ my $in;
+ foreach $in (<$fh>) {
+ chomp $in;
+ push @spots, [ split('\^', $in) ];
+ }
+ my $ref;
+ eval $eval; # do the search on this file
+ return ("error", $@) if $@;
+ }
+ }
+
+ 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;