#include "__SMTP_MAIL.h"
#include "SMTPServer.h"
#include "SPFChecker.h"

namespace mail {

   int __SMTP_MAIL::processCommand(coreutils::ZString &request, SMTPSession &session, SMTPServer &server) {

      if(request[1].ifNext("FROM:")) {
	 request[1].skipWhitespace();
	 if(request[1].ifNext("<")) {
	    session.from = request[1].getTokenExclude(">");
	    // Deliberately unconditional - not gated on authState. A
	    // receiving MX server accepts MAIL FROM addressed to its own
	    // local mailboxes from anyone; sending MTAs never AUTH to a
	    // destination domain, only to their own outbound smarthost.
	    // Authentication only needs to gate relaying to a NON-local
	    // recipient, which __SMTP_RCPT.cpp already does via
	    // session.relay. This used to be
	    // `if(session.authState = USER_KNOWN)` - an assignment, not
	    // a comparison - which accidentally produced this same
	    // "always accept" behavior; a literal `==` fix would instead
	    // have started rejecting all normal inbound mail.
	    session.out << "250 OK" << CRLF;
	    session.recipientList.clear();
	    session.state = MAIL;

	    // RFC 7208 2.4: the identity to check is the MAIL FROM
	    // address's own domain, or - for the null reverse-path <>
	    // bounce messages use, which has no domain of its own - the
	    // HELO/EHLO domain instead. Computed here (not deferred to
	    // DATA) since MAIL FROM is where the RFC actually anchors the
	    // check; DATA just reuses the result via session.spfHeader
	    // rather than re-running the DNS lookups a second time. This
	    // does block this connection's EPoll worker thread for
	    // however long the SPF DNS lookups take (matching
	    // SendMail::lookupMX()'s own res_query() calls, which are
	    // synchronous the same way) - acceptable for a well-behaved
	    // sender domain, not for a slow/hostile one, same tradeoff
	    // already accepted elsewhere in this codebase rather than a
	    // new one introduced here.
	    std::string fromStr = session.from.str();
	    size_t at = fromStr.find_last_of('@');
	    std::string spfDomain = (at == std::string::npos) ? session.clientDomainName.str() : fromStr.substr(at + 1);
	    std::string clientIP = session.ipAddress.getClientAddress();
	    session.spfDomain = spfDomain;
	    session.spfResult = SPFChecker::check(spfDomain, clientIP);
	    session.spfHeader = SPFChecker::receivedSPFHeader(session.spfResult, spfDomain, clientIP,
	                                                       session.clientDomainName.str(), server.hostName);
	 } else
	   session.out << "550 Usage: MAIL FROM:<email-address>" << CRLF;
      } else
	session.out << "550 Usage: MAIL FROM:<email-address>" << CRLF;
      return 1;
   }

}