<?php
$_dbUsr = "username"; // database username.
$_dbPass = "password"; // database password.
$_db = "database"; // database you're using.
$_dbHost = "localhost"; // most likely using localhost.        

$_conn = @mysql_connect($_dbHost, $_dbUsr, $_dbPass);    
if(!$_conn) { // This executes the connect code and checks it for errors.        
    print "Error: Problem connecting to database server. Please check your config files.";    
}    
$_select = @mysql_select_db($_db, $_conn);    
if(!$_select) { // Executes the select database code and checks it for errors.        
    print "Error: Problem selecting database. Please check that database exists and is linked properly in config files.";
}    
?>

<?php
require("config.php");

$_user = mysql_real_escape_string($_POST['user']);
$_pass = md5(sha1($_POST['pass'].$_POST['user']));
$_email = mysql_real_escape_string($_POST['email']);

$memtab = "name of your members table";
$_ip = $_SERVER['REMOTE_ADDR'];

if ((!$_user) || (!$_pass) || (!$_email)) {
    print "You must fill in all fields before clicking the register button. Please go back and try again.";
} else {
    $sel = @mysql_query("SELECT * FROM $memtab WHERE username = '$_user'");
    if($sel) {
        print "A user with that username exists. Please go back and choose a new username.";
    } else {
        $ins = @mysql_query("INSERT INTO $memtab (username, password, email, last_ip) VALUES(\"$_user\", \"$_pass\", \"$_email\", \"$_ip\")");

        if ($ins) {
            print "Registration complete. You may now begin using 'title of instant messenger'.";
        } else {
            print "Error: Could not create user. Please go back and try again.";
        }
    }
}
?>

<?php    
require("config.php");        
$memtab = "name of your members table";    
$_user = mysql_real_escape_string($_GET['user']);    
$_pass = md5(sha1($_GET['pass'].$_GET['user']));        
$_sel = @mysql_query("SELECT * FROM $memtab WHERE username=$_user AND password=$_pass");  
while($r = @mysql_fetch_array($_sel)) {    
    $_SESSION['user'] = $r["username"]; // There is going to be a session_start() function on top of index.php which will be the main page.
    $admin = $r["admin"];
}
if($admin) { // If the admin column has a value of 1
    print "<script language='text/javascript' src='ajax.js'>buddyLoad($_SESSION['user'],1);</script>";
} else {
    print "<script language='text/javascript' src='ajax.js'>buddyLoad($_SESSION['user'],0);</script>";
}
?>

<?php
if(!$_GET['m'] || !$_GET['from'] || !$_GET['to']) {
    print "No message was sent.";
} else {
    $user = mysql_real_escape_string($_GET['from']);
    $buddy = mysql_real_escape_string($_GET['to']);
    $msg = mysql_real_escape_string($_GET['m']);

    $ins = @mysql_query("INSERT INTO messages ('from', 'to', 'message') VALUES(\"$user\", \"$buddy\", \"$msg\")"); /* The reason for only inserting the from, to, and message fields is because the message id should be set to auto_increment and the time should default to CURRENT_TIMESTAMP. */
    
    if(!$ins) {
        print "Message could not be sent. The server may be down.";
    }
}
?>

<?php
require("config.php");
require("style.php"); // This will be the script that styles the way an instant message looks.

$user = mysql_real_escape_string($_GET['user']);
$buddy = mysql_real_escape_string($_GET['buddy']);
$time = $_GET['time'];

$sel = @mysql_query("SELECT * FROM messages WHERE to='$user' AND from='$buddy' ORDER BY time DESC LIMIT 1");
while($r = @mysql_fetch_array($sel)) {
    $id = $r["id"];
    $message = $r["message"];
    $dbtime = $r["time"];
}

if ($time == $dbtime) {
    return
} else {
    style($user,$buddy,$dbtime,$message); // Style the instant message and display it.
}

?>

/* This should be the same for all AJAX scripts. You find out if the person's browser supports AJAX and set the AJAX object to a variable. */    
var xmlhttp;    
try {    
     xmlhttp=new XMLHttpRequest();    
} catch (e) {    
     try {    
         xmlhttp=new ActiveXObject("Msxml2.XMLHTTP");    
     } catch (e) {    
         try {    
             xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");    
         } catch (e) {    
             alert("Your browser does not support AJAX!");    
             return false;    
         }    
    }    
}      
  
/* Since we're going to be using the GET method, we're going to check to see how long the url is with the message included. Since the max allowed length of a url is 2083 characters, we're going to make sure our url length is less than 2083 characters before we send the message to the intended buddy. */    
function checkIM() {
    var msg=document.getElementById('msg').value;
    var f=document.getElementById('user').value;
    var t=document.getElementById('buddy').value;
    var url='sendim.php?from='+f+'&to='+t+'&m='+msg;    
    if(url.length > 2083) {    
        document.getElementById('ims').innerHTML='Message too long.';    
    } else {    
        sendIM(url);    
    }    
}        

// After we've made sure the url is the right length, we can send it to our buddy.    
function sendIM(url) {    
     xmlhttp.onreadystatechange=function() {    
         if(xmlhttp.readyState==4) {    
             document.getElementById('ims').innerHTML+=xmlhttp.responseText;    
         }    
     }    
     xmlhttp.open("GET",url,true);    
     xmlhttp.send(null);    
}        

function cTime(time) {  
document.getElementById('time').value = time;
}

// This function is what we will be calling during the login process.    
function doLogin() {    
    var user=document.getElementById('username').value;    
    var pass=document.getElementById('pass').value;    
    var url='login.php?user='+user+'&pass='+pass;    
    xmlhttp.onreadystatechange=function() {    
        if(xmlhttp.readyState!=4) { // If the request is still loading, show loading image.                
            document.getElementById('main').innerHTML='<p><img src=images/loading.gif></p>';    
        } else {    
            document.getElementById('main').innerHTML=xhmlhttp.responseText;  
        }  
    }    
    xmlhttp.open("GET",url,true);    
    xmlhttp.send(null);    
}        

// The function we will be calling to show the users their buddylists.    
function buddyLoad(usr,admin) {    
    var url='buddylist.php?user='+usr+'&power='+admin;    
    xmlhttp.onreadystatechange=function() {    
        if(xmlhttp.readyState!=4) {    
            document.getElementById('main').innerHTML='<p><img src=images/loading.gif></p>';    
        } else {    
            document.getElementById('main').innerHTML=xmlhttp.responseText;            
        }    
    }        
    xmlhttp.open("GET",url,true);    
    xmlhttp.send(null);    
}        

// This will be what updates the users instant message window.    
function checkIMs() {    
    var usr=document.getElementById('user').value; // Hidden field with the persons username.        
    var f=document.getElementById('buddy').value; // Hidden field with the buddy's username.
var time=document.getElementById('time').value;
    var url='checkims.php?user='+usr+'&buddy='+f+'&time='+time;    
    xmlhttp.onreadystatechange=function() {    
        if(xmlhttp.readyState==4) {    
            document.getElementById('ims').innerHTML+=xmlhttp.responseText;
        }    
    }    
    xmlhttp.open("GET",url,true);    
    xmlhttp.send(null);    
}        

/* This is the instant message window timer that will run every second then call itself again to check for new im's. You can change the timer to run how ever often you would like it to, but keep in mind that if you have 20 users online, each with 5 im windows open, thats already 100 different timers running all calling the same php script from the checkIMs() function. This is where this idea may have problems. */    
function Timer() {    
    setInterval("checkIMs()", 1000);    
}

function Timer() {
    setInterval("checkIMs()", 1000);
    Timer();
}

function Timer() {    
    setInterval("checkIMs()", 1000);    
}

function Timer() {    
    setInterval("checkIMs()", 1000);    
}
Timer();