Simple Postcards

<form action="thispage.php4" method="post"> 
<input type ="hidden" name="BeenSubmitted" value="true"> 

<?php 
class mime_mail 
{ 
    var$parts; 
    var$to; 
    var$from; 
    var$headers; 
    var$subject; 
    var$body; 

    function mime_mail() 
        { 
        $this->parts=array(); 
        $this->to= ""; 
        $this->from= ""; 
        $this->subject= ""; 
        $this->body= ""; 
        $this->headers= ""; 
        } 

    function add_attachment($message,$name= "",$ctype= "application/octet-stream") 
        { 
        $this->parts[]=array( 
        "ctype"=>$ctype, 
        "message"=>$message, 
        "encode"=>$encode, 
        "name"=>$name 
        ); 
        } 

    function build_message($part) 
        { 
        $message=$part[ "message"]; 
        $message=chunk_split(base64_encode($message)); 
        $encoding= "base64"; 
        return "Content-Type:".$part[ "ctype"]. 
        ($part[ "name"]? ";name=\"".$part[ "name"]. "\"": ""). 
        "\nContent-Transfer-Encoding:$encoding\n\n$message\n"; 
        } 

    function build_multipart() 
        { 
        $boundary= "b".md5(uniqid(time())); 
        $multipart= "Content-Type:multipart/mixed;boundary=$boundary\n\nThisisaMIMEencodedmessage.\n\n--$boundary"; 
        for($i=sizeof($this->parts)-1;$i>=0;$i--) 
            { 
            $multipart.= "\n".$this->build_message($this->parts[$i]). "--$boundary"; 
            } 
        return$multipart.= "--\n"; 
        } 

    function send() 
        { 
            $mime= ""; 
            if(!empty($this->from)) 
            $mime.= "From:".$this->from. "\n"; 
            if(!empty($this->headers)) 
            $mime.=$this->headers. "\n"; 

            if(!empty($this->body)) 
            $this->add_attachment($this->body, "", "text/plain"); 
            $mime.= "MIME-Version:1.0\n".$this->build_multipart(); 
            return(mail($this->to,$this->subject, "",$mime)); 
        } 
}; 
?> 
<?php 


if (isset($BeenSubmitted)) { 
    $num_errors = 0; 
    if (! strlen($to) > 0) { 
        echo "You must enter an e-mail address for the recipient.<br>"; 
        $errors++; 
    } 
    if (! strlen($from) > 0) { 
        echo "You must enter your e-mail address.<br>"; 
        $errors++; 
    } 
    if (! strlen($subject) > 0) { 
        echo "You must enter a subject for the e-mail.<br>"; 
        $errors++; 
    } 
    if (! strlen($message) > 0) { 
        echo "You must enter some kind of message for the recipient.<br>"; 
        $errors++; 
    } 
    if (! $fp = @fopen($postcard,"r")) { 
        echo "You must select a postcard from the left.<br>"; 
        $errors++; 
    } 

    if ($errors == 0) { 
        $attachment=fread($fp,filesize("$postcard")); 
        $mail=new mime_mail(); 
        $mail->from="$from"; 
        $mail->to="$to"; 
        $mail->subject=stripslashes($subject); 
        $mail->body=stripslashes($message); 
        $mail->add_attachment("$attachment","$postcard","image/jpeg"); 
        if ($mail->send()) { 
         
        //if successful then writes info to a log file called log.txt. 
             
            $today = date("F j, Y, g:i a");                 // March 10, 2001, 5:16 pm 
            $filePointer = fopen("log.txt", "a"); 
            fputs($filePointer, "$today\t\t$from has sent this email to $to.\n"); 
             
            print ("Your email has been successfully sent!\n"); 
                     
        } else {          
            print ("Your email has been not been successfully sent because of a system error!\n"); 
        } 
    } 
} 
?> 

<p>Pick a postcard, fill out the information in the form boxes and click send!  Make someone happy. 

<p><img src="postcards/thumbnails/tn_butterfly.jpg" alt="" height="75" width="100" border="0"> 

<!-- Make sure that you have the correct path to the image in the value for the radio button(s) --> 

<br><input type="radio" name="postcard" value="/home/username/web_directory/images/butterfly.jpg"> Butterfly 

<p>Please fill out all of the information below.</p> 

<p>Recipient's Email: 
<br><input type="text" name="to" size="24" border="0"> 

<p>Your Email: 
<br><input type="text" name="from" size="24" border="0"> 

<p>Subject of Email: 
<br><input type="text" name="subject" size="24" border="0"> 

<p>Text of Message: 
<br><textarea name="message" rows="6" cols="30"></textarea> 

<p><input type="submit" value="Send Postcard"> <input type="reset"> 

</form>