<?php
//This page is responsible to return a JSON object
//code starts after the functions for those who might get confused xD
header('content-type: application/json; charset=utf-8');
global $responseData;
function AdjustRate($Ra, $Ea, $Sa)
{
//i used my own rules here 32 points for less than 500
if($Ra < 500)
$k = 32;
elseif ($Ra < 1000)//24 points for anything between 500 and 1000
$k = 24;
else
$k = 16;//16 for anything more than 1000
return $Ra + ($k*($Sa - $Ea));
}
function GetExpectedChance($rA, $rB) // the ELO formula taken from http://en.wikipedia.org/wiki/Elo_rating_system
{
return (1/(1+pow(10,(($rB-$rA)/400))));
}
function setNewRates($lastCall) // function I used to update my database tables
{
global $responseData;
$A = $lastCall->p1;
$B = $lastCall->p2;
$C = $lastCall->c;
$A->E = GetExpectedChance($A->rate, $B->rate);
$B->E = GetExpectedChance($B->rate, $A->rate);
// decide who won and who lost
if($A->id == $C){
$winner = $A;
$looser = $B;
}
elseif ($B->id == $C) {
$winner = $B;
$looser = $A;
}
// 3 cases, in all of them winner will get his rate/hits increased by 1
//Case #1: normal case we just update rate/hits for the winner, this applies all the time
$winner->rate += 1;
$winner->hits += 1;
//Case #2 / #3 : here we should adjust the rate after applying case #1
// if he won while he is expected to lose OR if he lost while expected to win
// there should be minimum rate different of 40 between the two
$diff = abs($winner->rate - $looser->rate);
if($diff >= 40 && ($winner->E < 0.5 || $looser->E >= 0.5)) {
$winner->rate = AdjustRate($winner->rate, $winner->E, 1);
$looser->rate = AdjustRate($looser->rate, $looser->E, 0);
}
// update the db to update rates, hits for both winner and looser
$updateQuery = 'UPDATE user SET rate='.$winner->rate.',hits='.$winner->hits.' WHERE id=' . $winner->id;
mysql_query($updateQuery);
$updateQuery = 'UPDATE user SET rate='.$looser->rate.' WHERE id=' . $looser->id;
mysql_query($updateQuery);
// Save to responsedate
$responseData->winner = $winner;
$responseData->looser = $looser;
}
//CODE STARTS HERE :)
// Setup the mysql connection
include 'db.php';
// Part 1: calculate the rate and save to db, if we have a lastcall
// GET the last call data object, it has p1, p2, c, these are the items i recieved from my javascript ajax call
$lastCall = json_decode((string)$_GET['lastCall']); // it was a JSON object so i need to decode it first
// Save last call data, will be sent with the respond as well
$responseData->lastCall = $lastCall;
// if there is a json object, means that there was a rating process and I have to set the new rates
if($lastCall->c != NULL)
{
setNewRates($responseData->lastCall);
}
// Part 3: Select new persons and addthem to our responseData
$q = Array();
$q[0] = 'SELECT id, name, sex, rate, hits FROM user WHERE fm_status=1 AND sex="female" ORDER BY RAND() LIMIT 2';
$q[1] = 'SELECT id, name, sex, rate, hits FROM user WHERE fm_status=1 AND sex="male" ORDER BY RAND() LIMIT 2';
// girls or boys ?
srand(mktime());
$query = $q[array_rand($q)];
$result1 = QueryIntoArray($query);
$responseData->user = $result1;
// Part 4: encode to JSON/JSONP string then respond to the call
$json = json_encode($responseData);
$json = isset($_GET['callback'])? "{$_GET['callback']}($json)" : $json;
echo $json;
mysql_close();
// by Noor Syron :)
//I used this in my www.mimm.me
?>