#include "readwrite.h"

#include "prioq.h"

#include "env.h"

#include "stralloc.h"

#include "subfd.h"

#include "substdio.h"

#include "getln.h"

#include "error.h"

#include "open.h"

#include "lock.h"

#include "gfrom.h"

#include "str.h"

#include "exit.h"

#include "myctime.h"

#include "maildir.h"

char *mbox;

char *mboxtmp;

stralloc filenames = {0};

prioq pq = {0};

prioq pq2 = {0};

stralloc line = {0};

stralloc ufline = {0};

char inbuf[SUBSTDIO_INSIZE];

char outbuf[SUBSTDIO_OUTSIZE];

#define FATAL "maildir2mbox: fatal: "

#define WARNING "maildir2mbox: warning: "

void die_nomem() { strerr_die2x(111,FATAL,"out of memory"); }

void main()

{

 substdio ssin;

 substdio ssout;

 struct prioq_elt pe;

 int fdoldmbox;

 int fdnewmbox;

 int fd;

 int match;

 int fdlock;

 umask(077);

 mbox = env_get("MAIL");

 if (!mbox) strerr_die2x(111,FATAL,"MAIL not set");

 mboxtmp = env_get("MAILTMP");

 if (!mboxtmp) strerr_die2x(111,FATAL,"MAILTMP not set");

 if (maildir_chdir() == -1)

   strerr_die1(111,FATAL,&maildir_chdir_err);

 maildir_clean(&filenames);

 if (maildir_scan(&pq,&filenames,1,1) == -1)

   strerr_die1(111,FATAL,&maildir_scan_err);

 if (!prioq_min(&pq,&pe)) _exit(0); /* nothing new */

 fdlock = open_append(mbox);

 if (fdlock == -1)

   strerr_die4sys(111,FATAL,"unable to lock ",mbox,": ");

 if (lock_ex(fdlock) == -1)

   strerr_die4sys(111,FATAL,"unable to lock ",mbox,": ");

 fdoldmbox = open_read(mbox);

 if (fdoldmbox == -1)

   strerr_die4sys(111,FATAL,"unable to read ",mbox,": ");

 fdnewmbox = open_trunc(mboxtmp);

 if (fdnewmbox == -1)

   strerr_die4sys(111,FATAL,"unable to create ",mboxtmp,": ");

 substdio_fdbuf(&ssin,read,fdoldmbox,inbuf,sizeof(inbuf));

 substdio_fdbuf(&ssout,write,fdnewmbox,outbuf,sizeof(outbuf));

 switch(substdio_copy(&ssout,&ssin))

  {

   case -2: strerr_die4sys(111,FATAL,"unable to read ",mbox,": ");

   case -3: strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

  }

 while (prioq_min(&pq,&pe))

  {

   prioq_delmin(&pq);

   if (!prioq_insert(&pq2,&pe)) die_nomem();

   fd = open_read(filenames.s + pe.id);

   if (fd == -1)

     strerr_die4sys(111,FATAL,"unable to read $MAILDIR/",filenames.s + pe.id,": ");

   substdio_fdbuf(&ssin,read,fd,inbuf,sizeof(inbuf));

   if (getln(&ssin,&line,&match,'\n') != 0)

     strerr_die4sys(111,FATAL,"unable to read $MAILDIR/",filenames.s + pe.id,": ");

   if (!stralloc_copys(&ufline,"From XXX ")) die_nomem();

   if (match)

     if (stralloc_starts(&line,"Return-Path: <"))

      {

       if (line.s[14] == '>')

	{

         if (!stralloc_copys(&ufline,"From MAILER-DAEMON ")) die_nomem();

	}

       else

	{

	 int i;

         if (!stralloc_ready(&ufline,line.len)) die_nomem();

         if (!stralloc_copys(&ufline,"From ")) die_nomem();

	 for (i = 14;i < line.len - 2;++i)

	   if ((line.s[i] == ' ') || (line.s[i] == '\t'))

	     ufline.s[ufline.len++] = '-';

	   else

	     ufline.s[ufline.len++] = line.s[i];

         if (!stralloc_cats(&ufline," ")) die_nomem();

	}

      }

   if (!stralloc_cats(&ufline,myctime(pe.dt))) die_nomem();

   if (substdio_put(&ssout,ufline.s,ufline.len) == -1)

     strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

   while (match && line.len)

    {

     if (gfrom(line.s,line.len))

       if (substdio_puts(&ssout,">") == -1)

         strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

     if (substdio_put(&ssout,line.s,line.len) == -1)

       strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

     if (!match)

      {

       if (substdio_puts(&ssout,"\n") == -1)

         strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

       break;

      }

     if (getln(&ssin,&line,&match,'\n') != 0)

       strerr_die4sys(111,FATAL,"unable to read $MAILDIR/",filenames.s + pe.id,": ");

    }

   if (substdio_puts(&ssout,"\n"))

     strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

   close(fd);

  }

 if (substdio_flush(&ssout) == -1)

   strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

 if (fsync(fdnewmbox) == -1)

   strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

 if (close(fdnewmbox) == -1) /* NFS dorks */

   strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");

 if (rename(mboxtmp,mbox) == -1)

   strerr_die6(111,FATAL,"unable to move ",mboxtmp," to ",mbox,": ",&strerr_sys);

 while (prioq_min(&pq2,&pe))

  {

   prioq_delmin(&pq2);

   if (unlink(filenames.s + pe.id) == -1)

     strerr_warn4(WARNING,"$MAILDIR/",filenames.s + pe.id," will be delivered twice; unable to unlink: ",&strerr_sys);

  }

 _exit(0);

}