Unique Forgot Password

CREATE TABLE `verify` (
`username` VARCHAR( 255 ) NOT NULL,
`code` VARCHAR( 255 ) NOT NULL,
);

<?php 
//checks if there trying to veriy there account
if(isset($_GET['verify'])) { //your on the form verify
$code = addslashes($_GET['code']); //gets the url and adds to verify
$getcode = mysql_query("SELECT * FROM `verify` WHERE code = '$code'"); //grabs the data from the code you clicked in the email
$p = mysql_fetch_array($getcode); //arrays it the info
$alphanum = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"; //here is the available characters it will choose from for your new password
$coded = substr(str_shuffle($alphanum), 0, 7); //then it takes the characters listed above and shuffles it around and picks the first 7
$newpassword = sha1(md5(md5(sha1(md5(sha1(sha1(md5($coded)))))))); //this makes the passwors secure so you can login
$update_pass = mysql_query("UPDATE `members` SET `password` = '$newpassword' WHERE `username` = '$p[username]';") or die(mysql_error()); 
//updates the password with the newpassword
echo "<style>
#np {
background: #D7F9C6;
border: 1px solid #649A49;
padding: 4px;
color: #388014;
}
</style>
 
<div id=np>Hello $p[username], your new password is: <b>$coded</b>. Copy and paste the your new password when you <a href=https://sodadome.com/login.php>login</a>. If it doesn't work. Type it out - remember its cAsE sEnSiTiVe.</div><br><hr><br><br>";
//the echo is where it shows your 
$delete = mysql_query("DELETE FROM `verify` WHERE code = '$code'"); //then deletes the verifaction you clicked so its unique and the pass is reset by you only
} //just a curely bracket on line 24 that ends the what it started on line 3 
if(isset($_GET['true'])) { //when you send the form
$alphanum  = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"; //available characters for your verification code
$code = substr(str_shuffle($alphanum), 0, 16);//shuffles it around and takes first 16 characters
$username = $_POST['username']; //takes the username and gives variable
mysql_query("INSERT INTO `jsfdan_cnews`.`verify` (`username` ,`code`) VALUES ('$username', '$code');") or die(mysql_error()); 
//inserts verification code and username
$fetch = mysql_query("SELECT * FROM `members` WHERE `username` = '$username'"); //grabs the data on the username you entered
$user = mysql_fetch_array($fetch); //puts it into more shorter variable 
$mail = mail("$user[email]", "Password Recovery from sodaDome.com", "Hello $username, it seems you have forgotten your password. To get a new one, please click the link below
 
 https://sodadome.com/forgotpass.php?verify&code=$code
 
 Thanks and have a nice day.", "From: bot@sodadome.com");
 
echo "Please check your email, $username.";//emails the user
}else{
 
if(!$_POST['fpas']){ //form not submitted
echo "<form action='?true' method='post'>Forgot Your password?<br><br>
 
Enter your Username: <input type='text' name='username' size='30' maxlength='15'><br><br>
 
<input type='submit' value='Submit!' name='fpas'>";
}
}
?>