#!/usr/local/bin/perl
# *********************************************************************** #
# *									* #
# *                Copyright (c) 1996-1999 Scott Crevier		* #
# *                    All Rights Reserved Worldwide			* #
# *									* #
# *  This program product material is the property of Scott Crevier.	* #
# *  This program may be used and modified by anyone free of charge,	* #
# *  as long as this copyright notice remains in tact. By using this	* #
# *  code, you agree to indemnify Scott Crevier from any liability	* #
# *  that might arise from its use.					* #
# *									* #
# *     scott@crevier.org  -  Scott M. Crevier  -  www.crevier.org      * #
# *********************************************************************** #
# *  smcAdShow v2.0					21-Dec-1998	* #
# *									* #
# *  The purpose of this program is to display an image on a web page	* #
# *  and log the fact that it was displayed. The log can then be used	* #
# *  reference purposes or for advertiser billing.			* #
# *									* #
# *  Suggested usage via server-side include:				* #
# *    <!--#exec cgi="/cgi-bin/smcAdShow.pl"-->				* #
# *									* #
# *  The concept behind this script is that you start by creating a	* #
# *  text file with definitions for each image in the rotation. This	* #
# *  script will read that file and decide which image should be	* #
# *  displayed. Your text file will contain one image definition on	* #
# *  each line. The syntax expected in this file is explained below.	* #
# *									* #
# *	imgURL;width;height;border;$logfile;$url;$alt			* #
# *									* #
# *	imgurl	= the url to the image file				* #
# *	width	= the width of the image (pixels)			* #
# *	height	= the height of the image (pixels)			* #
# *	border	= the border size to display for this image		* #
# *	logfile	= the name of the logfile for this image		* #
# *	url	= the URL that this image should link to		* #
# *	alt	= the alt text to display with this image		* #
# *									* #
# *  The logfile setting simply lets you have a separate log for each	* #
# *  image (like if you want to allow your advertisers view only their	* #
# *  log). But if you want all image activity in the same log, then	* #
# *  just use the same name for all images defined in the file.		* #
# *									* #
# *  This script will decide which image to display by splitting a	* #
# *  calendar minute into n equal parts, where n is the number of	* #
# *  lines in the file. For example, if there are 4 lines in the file,	* #
# *  the 1st image in the file will be displayed during the 1st 15	* #
# *  seconds of each minute; the 2nd image will be displayed during	* #
# *  2nd 15 seconds of each minute, etc.				* #
# *									* #
# *  If you are in a different time zone than the machine where your	* #
# *  web site resides, you can set the $hours_to_add variable to tell	* #
# *  this script to log the times in your local time zone.		* #
# *									* #
# *********************************************************************** #
print "Content-type: text/html\n\n";


# *********************************************************************** #
# *  get the current date/time						* #
# *********************************************************************** #
$now = &getNow;


# *********************************************************************** #
# *  Define some variables.						* #
# *********************************************************************** #
$datafile	= '/path/to/your/image/data/file';
$logfiledir	= '/path/to/your/logfile/directory';
$hours_to_add	= -3;


# *********************************************************************** #
# *  count the lines in the source file					* #
# *********************************************************************** #
open(SRC,$datafile) or die "$! \'$datafile\'";
$cnt = @lines = <SRC>;
close(SRC);


# *********************************************************************** #
# *  Using my "up-to-bat" algorithm, determine which line in the file	* #
# *  to use.								* #
# *********************************************************************** #
$linenum = (int($sec / (60 / $cnt)) == 0) ? $cnt : int($sec / (60 / $cnt));


# *********************************************************************** #
# *  Get the variables from the line in the file.			* #
# *********************************************************************** #
($img,$width,$height,$border,$logfile,$url,$alt) = split(/;/,$lines[--$linenum]);

$logfile = $logfiledir . $logfile;


# *********************************************************************** #
# *  This following line is optional. It allows you to use my adtrack	* #
# *  script to log the actual click-throughs on the image. If you don't	* #
# *  need this, then just comment out the following line.		* #
# *********************************************************************** #
$url = '/cgi-bin/smcAdTrack.pl?' . $url;


# *********************************************************************** #
# *  Print the html code for the image, including a link to the web	* #
# *  site that the image represents.					* #
# *********************************************************************** #
print <<imgTag;
<a href="$url"><img src="$img" width="$width" height="$height" border="$border" alt="$alt"></a>
imgTag


# *********************************************************************** #
# *  Log this instance.							* #
# *********************************************************************** #
open(LOGFILE,">> $logfile") or die "$! \'$logfile\'";
print (LOGFILE "[$now]  $url\n");
close(LOGFILE);


# *********************************************************************** #
# *				END					* #
# *********************************************************************** #
exit(0);


# *********************************************************************** #
# *  Subroutine to return the current date/time. You can customize	* #
# *  this so that it uses whatever format you are most comfortable	* #
# *  with.								* #
# *********************************************************************** #
sub getNow {

	($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime(time + ($hours_to_add * 3600));

	$year	+= 1900;
	$mon	= sprintf("%02d", $mon);
	$mday	= sprintf("%02d", $mday);
	$hour	= sprintf("%02d", $hour);
	$min	= sprintf("%02d", $min);
	$sec	= sprintf("%02d", $sec);

	return "${year}-${mon}-${mday} ${hour}:${min}:${sec}";
}