<?php
/****************************************************************************
 * DRBRatings
 * http://www.dbscripts.net/ratings/
 * 
 * Copyright (c) 2007-2010 Don B 
 ****************************************************************************/

$CHECK_FOR_DUPLICATE_RATINGS = TRUE;
$CREDIT_LINK_REMOVAL_LICENSE = FALSE;

include_once(dirname(__FILE__) . '/config.php');

$rating_fp = NULL;

function show_ratings_control($id) {
	global $MAX_STARS;
	global $RATING_STRING;
	global $NUMBER_OF_RATINGS_STRING;
	global $CURRENT_RATING_STRING;
	
	// Validate parameters
	if(!is_valid_id($id)) {
		rating_die('ERROR: An invalid rating ID was submitted.');
	}
	
	// Lock
	rating_lock($id, LOCK_SH);
		
	// Get the current rating and rating count
	$summarylist = rating_summary_list($id);
	$ratingCount = get_rating_count($summarylist);
	$rating = get_current_rating($summarylist);
	
	// Unlock
	rating_unlock();
	
	// Initialize the display messages for the rating control
	$ratingString = sprintf($RATING_STRING, $rating, $MAX_STARS);
	$numberOfRatingsString = sprintf($NUMBER_OF_RATINGS_STRING, $ratingCount);

	// Output rating control
	echo("<div class=\"ratingsContainer\">\r\n");
	echo("\t<div class=\"currentRating\">" . htmlspecialchars($CURRENT_RATING_STRING) . "</div>\r\n");
	echo("\t<div class=\"rating\">\r\n");
	show_stars($rating);
	echo("\t\t" . htmlspecialchars($ratingString) . "\r\n\t</div>\r\n");
	echo("\t<div class=\"numberOfRatings\">" . htmlspecialchars($numberOfRatingsString) . "</div>\r\n");
	show_rate_form($id);
	the_credits();
	echo("</div>\r\n");
	
}

function show_rate_form($id) {
	global $RATE_THIS_STRING;
	global $MAX_STARS;
	global $SUBMIT_BUTTON_STRING;
	global $RATING_LABELS;
	global $RATING_LIST_DEFAULT_LABEL;
	global $RATINGS_URL;
	global $RATING_ID_PARAM_NAME;
	global $RATING_PARAM_NAME;
	
	echo("\t<form class=\"rateIt\" method=\"post\" action=\"" . $RATINGS_URL . "rate.php\">\r\n");
	echo("\t\t" . htmlspecialchars($RATE_THIS_STRING) . "\r\n");
	echo("\t\t<select name=\"" . htmlspecialchars($RATING_PARAM_NAME) . "\">\r\n");
	echo("\t\t\t<option value=\"\">" . htmlspecialchars($RATING_LIST_DEFAULT_LABEL) . "</option>\r\n");
	for($i = 1; $i <= $MAX_STARS; $i++) {
		echo("\t\t\t<option value=\"" . $i . "\">" . $i);
		if(!empty($RATING_LABELS) && isset($RATING_LABELS[$i])) {
			echo(" - " . htmlspecialchars($RATING_LABELS[$i]));
		}
		echo("</option>\r\n");
	}
	echo("\t\t</select>\r\n");
	echo("\t\t<input type=\"hidden\" name=\"" . htmlspecialchars($RATING_ID_PARAM_NAME) . "\" value=\"" . htmlspecialchars($id) . "\" />\r\n");
	echo("\t\t<input type=\"submit\" value=\"" . htmlspecialchars($SUBMIT_BUTTON_STRING) . "\" class=\"submit\" />\r\n");
	echo("\t</form>\r\n");
	
}

function show_stars($rating) {
	global $IMAGE_STAR_EMPTY;
	global $IMAGE_STAR_HALF;
	global $IMAGE_STAR_FILLED;
	global $MAX_STARS;

	// Iterate through the stars, and show the correct type of star image 
	// based on the rating.
	for($i = 1; $i <= $MAX_STARS; $i++) {
		
		if($rating > $i - .5) {
			show_ratings_image($IMAGE_STAR_FILLED, "*");
		} else if($rating > $i - 1) {
			show_ratings_image($IMAGE_STAR_HALF, "1/2");
		} else {
			show_ratings_image($IMAGE_STAR_EMPTY, "");
		}
		
	}

}

function show_ratings_image($filename, $alt) {
	global $RATINGS_URL;
	echo("\t\t<img src=\"" . $RATINGS_URL . urlencode($filename) . "\" alt=\"" . htmlspecialchars($alt) . "\" />\r\n");
}

function smarter_is_int($val) {
    return (is_numeric($val)?intval($val)==$val:FALSE);
}

function is_valid_id($id) {
	global $VALID_RATING_IDS;
	return (!empty($id) && preg_match('/^[a-zA-Z0-9]+$/D', $id) === 1 && in_array($id, $VALID_RATING_IDS, TRUE));
}

function is_valid_rating($rating) {
	global $MAX_STARS;
	return (!empty($rating) && preg_match('/^[1-9][0-9]*$/D', $rating) === 1 && smarter_is_int($rating) && $rating >= 1 && $rating <= $MAX_STARS);
}

function get_rating_count($summarylist) {

	// Get rating count from summary
 	if($summarylist === FALSE || count($summarylist) < 1) {
 		return 0;
 	} else {
 		return $summarylist[0];
 	}
	
}

function get_current_rating($summarylist) {
	global $MAX_STARS;
	
	// Get total count
	$totalCount = get_rating_count($summarylist);
	if($totalCount == 0) return 0;	// Prevent divide by zero
	
	// Calculate total ratings
	$totalRatings = 0;
	if($summarylist !== FALSE) {
	 	for($i = 1; $i <= $MAX_STARS; $i++) {
	 		if($i < count($summarylist)) {
	 			$totalRatings += $summarylist[$i] * $i;
	 		}
	 	}
	}
	
	// Return average
	global $RATINGS_PRECISION;
	return round($totalRatings / $totalCount, $RATINGS_PRECISION);
	
}

function add_new_rating($id, $rating) {
	global $rating_error_message;
	
	// Make sure rating wasn't left blank
	if(empty($rating)) {
		global $NO_RATING_SELECTED_ERROR_MSG;
		$rating_error_message = $NO_RATING_SELECTED_ERROR_MSG;
		return FALSE;
	}
	
	// Validate parameters
	if(!is_valid_id($id)) {
		rating_die('ERROR: An invalid rating ID was submitted.');
	}
	if(!is_valid_rating($rating) ) {
		rating_die('ERROR: An invalid rating was submitted.');
	}
	
	// Convert to integer value
	$rating = intval($rating);
	
	// Lock
	rating_lock($id, LOCK_EX);
	
	// Check for duplicate rating attempt
	global $CHECK_FOR_DUPLICATE_RATINGS;
	if($CHECK_FOR_DUPLICATE_RATINGS === TRUE) {
		$ipaddress = $_SERVER['REMOTE_ADDR'];
		if(has_rated($id, $ipaddress)) {
			global $DUPLICATE_RATE_ERROR_MSG;
			$rating_error_message = $DUPLICATE_RATE_ERROR_MSG;
			rating_unlock(); // Unlock
			return FALSE;
		}
	}

	// Add rating	
	rating_history_add($id, $ipaddress, $rating);
	rating_summary_add($id, $rating);
	
	// Unlock
	rating_unlock();
		
	return TRUE;
	
}

function rating_summary_file_path($id) {
 	return dirname(__FILE__) . '/data/summary_' . $id . '.dat';
}

function rating_history_file_path($id) {
	return dirname(__FILE__) . '/data/history_' . $id . '.dat';
}

function rating_lock_file_path($id) {
	return dirname(__FILE__) . '/data/lock_' . $id . '.dat';
}

function rating_summary_list($id) {

	// Load existing
	$summarylist = @file(rating_summary_file_path($id));
	if($summarylist !== FALSE) {
		$summarylist = array_map("trim", $summarylist);
	}
	return $summarylist;

}

function rating_summary_add($id, $rating) {

	// Get existing ratings
	$summarylist = rating_summary_list($id);
	
	// Open/create summary file
 	$summary_fp = @fopen(rating_summary_file_path($id), "w");
 	if($summary_fp === FALSE) {
 		rating_die("Unable to open summary file for writing");
 	}
 	
 	// Update total rating count
 	if($summarylist === FALSE || count($summarylist) < 1) {
 		$count = 1;
 	} else {
 		$count = $summarylist[0] + 1;
 	}
 	fputs($summary_fp, $count . "\n");

	// Add rating to history 	
 	global $MAX_STARS;
 	for($i = 1; $i <= $MAX_STARS; $i++) {
 		
 		if($summarylist === FALSE || $i > count($summarylist) + 1) {
 			
 			// This is the first rating for this number
 			if($i == $rating) {
 				$out = 1;
 			} else {
 				$out = 0;
 			}
 			
 		} else {
 			
 			// Add to existing rating count for this number
 			if($i == $rating) {
 				$out = ($summarylist[$i] + 1);
 			} else {
 				$out = $summarylist[$i];
 			}
 			
 		}
 		
 		// Write out new rating count for this number
 		fputs($summary_fp, $out . "\n");
 		
 	}
 	fclose($summary_fp);
	
}

function rating_history_add($id, $ipaddress, $rating) {
	
	// Open/create history file
 	$history_fp = @fopen(rating_history_file_path($id), "a");
 	if($history_fp === FALSE) {
 		rating_die("Unable to open history file for writing");
 	}
 	
 	// Add IP address and rating to history
 	fputs($history_fp, $ipaddress . "|" . $rating . "\n");
 	fclose($history_fp);
 	
}

function explode_history($line) {
	return array_map("trim", explode("|", $line));
}

function rating_history_list($id) {

	// Load existing rating history
	$summarylist = @file(rating_history_file_path($id));
	if($summarylist !== FALSE) {
		$summarylist = array_map("explode_history", $summarylist);
	}
	
	return $summarylist;
	
}

function has_rated($id, $ipaddress) {

	// Find rating history
	$rating_history_list = rating_history_list($id);
	if($rating_history_list !== FALSE) {
		return( find_rating_history(trim($ipaddress), $rating_history_list) !== FALSE );
	} else {
		return FALSE;
	}

}

function find_rating_history($ipaddress, $list) {
	
	// Search rating history for this IP address
	if(!empty($list)) {
		for($i = 0; $i < count($list); $i++) {
			if($list[$i][0] == $ipaddress) return $list[$i];
		}
	}
	return FALSE;
	
}

function rating_die($msg) {
	rating_unlock();
	die($msg);
}

function rating_lock($poll_id, $operation) {
	global $rating_fp;
	if($rating_fp !== NULL) {
		rating_die("Already locked for rating");
	}
	$rating_fp = @fopen(rating_lock_file_path($poll_id), 'a');
	if($rating_fp === FALSE) die("Unable to open lock file");
	if(@flock($rating_fp, $operation) === FALSE) {
		@fclose($rating_fp);
		die("Unable to lock for rating");
	}
	return;
}

function rating_unlock() {
	global $rating_fp;
	if($rating_fp !== NULL) {
		@flock($rating_fp, LOCK_UN);
		@fclose($rating_fp);
		$rating_fp = NULL;
	}
}

/* DO NOT REMOVE OR HIDE THE CREDIT BELOW, PER LICENSE! */
function the_credits() {
 	global $CREDIT_LINK_REMOVAL_LICENSE;
	if($CREDIT_LINK_REMOVAL_LICENSE !== TRUE) {
		$line = "PGRpdiBjbGFzcz0iY3JlZGl0IiBzdHlsZT0iZm9udC1zaXplOiA4cHQ7Ij5Qb3dlc"
		. "mVkIGJ5IERSQlJhdGluZ3MgJm1pZGRvdDsgPGEgaHJlZj0iaHR0cDovL3d3dy5kYnNjcmlw"
		. "dHMubmV0L2hvc3RpbmcvIj5QSFAgSG9zdGluZzwvYT48L2Rpdj4=";
		echo(base64_decode($line) . "\n");
	}
}
/* END CREDIT */

?>