#!/usr/local/bin/perl
#	
#	Name	:cronad
#	Author	:Kang SoonLai
#	Date	:Mon Oct 27 17:14:42 CST 1997	v1.0
#	Path	:/home/skang/public_html/programs/cronad
#	Email	:skang@granax.com
#	WWW	:http://www.granax.com/~skang
#
#	this script is useful when you don't have cgi access but you have cron
#	access.  It can then be used to rotate your banner on your pages.
#	it looks for a begin tag, <!-- banner -->, and an end tag, 
#	<!-- end banner -->, and replace all the texts inside with a new
#	random banner text.  it uses the same stat file as cookiead uses.
#	this makes sure that it compatible with all my ad programs.
#
#	how to use:
#	1. Create a dir call it banner in your public_html dir.  This is your
#	$dir var.  If your server doesn't use public_html as the default user
#	html dir, then you have modify the $dir var below.
#
#	2. Create a dir in banner dir that you have just created, call it pics.
#	this dir contains all the banner imgs.  Then modify the $IMGURL to 
#	where your banners pics are.
#
#	3. Create 2 stat files.  One call it stat, and another one with a .cron
#	extension, stat.cron.  Stat file has a format like this: (if you have
#	used cookiead or ad, then u can use the same stat file.)
#		url1%%banner_img_name%%
#		www.granax.com/~skang%%skang.jpg%%1
#  	notice that url doesn't include the http:// str, just the domain name.
#	and banner_img_name is the file name of banner itself.  and finally
# 	the weight of the banner.  If you want the banner to show up more
#	often on your pages, then put a higher number there.
#	stat.cron contains the dirs to where cronad should process.  Cronad
#	opens the file, and go to the dirs specified, and process all .html
#	files.
#
#	4. Finally, you need to submit this to a cron job if you decide to.  If
#	don't have access to a cron, then you might have to do it manually.
#	Here is a simple command edit a cron file:
#		crontab -e
#	then put this line if you want to have it do it every hour for u:
#		20 * * * * /users/skang/bin/cronad 	
#	* Please provide the full patht to your cronad program.
#
#	I hope this will help you to make some profit from banner advertising.
#
##############################################################################

require "imgsize";

# tag to parse
$tag ="banner";

# the base url to the banner images, this is the url where all the banner pics
# located.  
$IMGURL = "http://freenshare.granax.com/pics/ads";

# dir to where the banner info located.  contains the stat file, pics dir,
# tmp/ip files, etc.
#
$dir = "$ENV{HOME}/public_html/banner";
$PICSDIR = "$dir/pics";

$default = "freenshare.granax.com";

# this file contains the information about the banner to be displayed
# it has the format ->	url%%img%%frequency%%showed_frequency
# ** currently, the showed_freq is not implemented yet.
#
$file = "stat" unless $file;

#
# generate a random img and url to go to, and set cookie no matter the browser 
# supports cookie or not.  if there is no HTTP_COOKIE defined, then create a 
# file so that the action 'url' will be able to get the url.

open(F,"$dir/$file") || die "Error opening file $dir/$file: $!\n";

	while (chop($line = <F>)) {
		my($url,$img,$freq,$sfreq) = split(/%%/,$line);
		push(@imgs,"$img");
		push(@urls,"$url");
	
		for ($i=0; $i<$freq; $i++) {
			push(@imgs,"$img");
			push(@urls,"$url");
		}
	}
	close(F);

	srand(time|$$);

open(DF,"$dir/$file.cron") || die "Error opening file $dir/$file.cron: $!\n";

# process all dirs specified in $file.cron
while ($dir=<DF>) {
	chop $dir;

	# process all files in dir.
	opendir(DIR,$dir) || die "Can't open $dir: $!\n";
	readdir DIR;
	readdir DIR;

	@files = readdir DIR;
	while ($f = pop @files) {

		# only process file with html extension.
		if ($f =~ /html$/) {

		open(PF,"$dir/$f") || die "Error opening file $dir/$f: $!\n";
		open(NF,">$dir/$f.new") || die "Error opening file $dir/$f.new: $!\n";

		$changed = 0;
		print "\nprocessing $dir/$f\n";

		# parse file, and insert banner link.		
		while ($l=<PF>) {
			if ( $l eq "<!-- $tag -->\n") {
				while ( ($l1=<PF>)  &&
					($l1 ne "<!-- end $tag -->\n") ) {}
				my $link = &mk_link;
				print NF <<EOH;
<!-- $tag -->
<table width=600>
<tr><td align=center>
$link
</td></tr>
</table>
<!-- end $tag -->
EOH
				;
				$changed = 1;
			} else {
				print NF $l;
			}
		}

		# remove temp file, or mv temp file
		if ($changed) {
			system "mv -f $dir/$f.new $dir/$f";
		} else {
			unlink "$dir/$f.new";
		} 

		}
	}
}




sub mk_link {

	# pick a random seed to randomly display banner
	my $random = int(rand(scalar(@imgs)));

	my $cookie = $urls[$random];
	my $pic = "$imgs[$random]";

	my $size = &getsize("$PICSDIR/$pic");
	#print "<a href='http://$cookie'><img src='$IMGURL/$pic' $size></a>\n";
	return "<a href='http://$cookie'><img\nsrc='$IMGURL/$pic'\nalt='Cool site, click' $size></a>";

}