#!/usr/bin/perl -w
#    use strict;
    use diagnostics;
    use CGI;
    use CGI::Carp qw(fatalsToBrowser);

	# constants
	@months = ("January", "February", "March", "April", "May",
	"June", "July", "August", "September", "October", "November",
	"December"); 

	# globals
	%events = (); # Create has to keep events sorted by date
    $q = new CGI; # Create an instance of CGI
	
sub PrintMonth{
	my $mo = shift();
	my $yr = shift();

	print "<table cols=7 border=1 bgcolor=#ffffff text=#3D663D>\n";
	print "<font size=-2>\n";
	print "\t<tr align=center>\n";
	print "\t\t<td> "; 
	if ($mo > 1){
		printf "<a href=\"%s?mo=%d&yr=%s\">",$q->url(),$mo-1,$yr;
		print "&lt;</a>";
	}else{
		printf "<a href=\"%s?mo=12&yr=%s\">",$q->url(),$yr-1;
		print "&lt;</a> ";
	}
	print "</td>\n";
	print "\t\t<td colspan=5> $months[$mo-1] $yr</td>\n";
	print "\t\t<td> "; 
	if ($mo < 12){
		printf "<a href=\"%s?mo=%d&yr=%s\">",$q->url(),$mo+1,$yr;
		print "&gt;</a>";
	}else{
		printf "<a href=\"%s?mo=1&yr=%s\">",$q->url(),$yr+1;
		print "&gt;</a> ";
	}
	print "</td>\n\t</tr>\n";
	my @cal = `cal $mo $yr`;
	shift(@cal);
	while(@cal){
		print "\t<tr align=center>\n";
		$line = shift(@cal);
		foreach $i (0..6) {
			unless (length($line) - $i*3 < 2){
				$day = substr($line,$i*3,2); 
				$idxday = $day; # Build hash index from date
				$idxday =~ tr/ /0/; 
				$idxday = $mo.$idxday.$yr;
				print "\t\t<td>";
				if (exists($events{$idxday})){
					print "<a href=\"$events{$idxday}\" target=main>";
					print "$day</a>";
				}else{
					print $day;
				}
				print "</td>\n";
			}
		}
		print "\t</tr>\n";
	}
	print "</font>\n";
	print "</table>\n";
}

# Read events file:
sub ReadFile{
	my $fname = shift();
	open(EVENTS,$fname) or die "can't open events file";
	while (<EVENTS>){
		chop;
		my ($date,$url) = split('\^');
		$events{$date+0}=$url; #get rid of the eventual 0
	}
}

    # Send an appropriate MIME header
    print $q->header(-type => "text/html");
    # Send some content
    print $q->start_html(-title => "Calendar Script",
		-bgcolor => "#3d663d");
	ReadFile('events.txt');
	my ($yr,$mo) = (0,0); #get rid of stupid perl warning
	if($q->param()){
		($mo,$yr) = ($q->param('mo'),$yr = $q->param('yr'));
	}else{
		@dateinfo = localtime;
		($mo,$yr) = ($dateinfo[4]+1,$dateinfo[5]+1900);
	}
	PrintMonth($mo,$yr);
    print $q->end_html;