#include <unistd.h>
#include <sys/types.h>
#include "control.h"
#include "sig.h"
#include "constmap.h"
#include "readwrite.h"
#include "exit.h"
#include "env.h"
#include "qmail.h"
#include "auto_qmail.h"
#include "buffer.h"
#include "str.h"
#include "fmt.h"
#include "stralloc.h"
#include "logmsg.h"
#include "srs2.h"

#define WHO "srsforward"

void die_nomem() { logmsg(WHO,111,FATAL,"out of memory"); } 
void die_control() { logmsg(WHO,110,FATAL,"Unable to read control files"); }

struct qmail qqt;
char *srsdomaininfo = 0;
stralloc srsdomains = {0};
struct constmap mapsrsdomains;
stralloc srshost = {0};
stralloc srserror = {0};

/** @file  srsforward.c
    @brief forwarding mails with SRS enhanced addresss
    @return   0 on success (forwarded or not)
             -3 SRS error with error output
            111 no memory / processing error
            110 control file not readable
*/

static int srserror_str(int code) {
  if (!stralloc_copys(&srserror,"SRS: ")) die_nomem();
  if (!stralloc_cats(&srserror,srs_strerror(code))) die_nomem();
  if (!stralloc_0(&srserror)) die_nomem();
  return -3;
}

ssize_t mywrite(int fd,char *buf,int len)
{
  qmail_put(&qqt,buf,len);
  return len;
}

char inbuf[BUFSIZE_LINE];
char outbuf[BUFSIZE_LINE];
buffer bi = BUFFER_INIT(read,0,inbuf,sizeof(inbuf));
buffer bo = BUFFER_INIT(mywrite,-1,outbuf,sizeof(outbuf));

char num[FMT_ULONG];

int main(int argc,char **argv)
{
  int i, j, r;
  char *qqx;
  srs_t *srs;
  stralloc cookie = {0};
  char separator = '=';
  char srssender[512];
  char *host = 0;
  char *sender = 0;
  char *dtline = 0;
  char *sendhost = 0;
  int alwaysrewrite = 0;

  sig_pipeignore();
 
  sender = env_get("NEWSENDER");
  if (!sender)
    logmsg(WHO,100,FATAL,"NEWSENDER not set");
  host = env_get("HOST");
  if (!host)
    logmsg(WHO,100,FATAL,"HOST not set");
  dtline = env_get("DTLINE");
  if (!dtline)
    logmsg(WHO,100,FATAL,"DTLINE not set");

  if (chdir(auto_qmail) == -1)
    logmsg(WHO,111,FATAL,B("unable to chdir to: ",auto_qmail));

  if (!stralloc_cats(&srshost,"!")) die_nomem();
  if (!stralloc_cats(&srshost,host)) die_nomem();

  switch (control_readfile(&srsdomains,"control/srsdomains",0)) {
    case -1: die_control();
    case  0: if (!constmap_init(&mapsrsdomains,"",0,1)) die_nomem(); break;
    case  1: if (!constmap_init(&mapsrsdomains,srsdomains.s,srsdomains.len,1)) die_nomem(); break;
  }
  if (constmap(&mapsrsdomains,srshost.s,srshost.len)) return 0;           // domain blacklisted
  if ((srsdomaininfo = constmap(&mapsrsdomains,host,str_len(host))) == 0) {
    if ((srsdomaininfo = constmap(&mapsrsdomains,"*",1)) == 0) return 0;  // '*' means always SRS
    else alwaysrewrite = 1;
  }

  if (*srsdomaininfo) {
    i = str_chr(srsdomaininfo,'|');              // multiple cookies; separated by  ' '
    if (srsdomaininfo[i] == '|') {
      srsdomaininfo[i] = 0;
      j = str_chr(srsdomaininfo + i + 1,'|'); 
      if (srsdomaininfo[i + j + 1] == '|') {
        srsdomaininfo[i + j + 1] = 0;
        sendhost = srsdomaininfo + i + j + 2;    // separator: - + =
      }
      separator = srsdomaininfo[i + 1];
    }
    if (!stralloc_copys(&cookie,srsdomaininfo)) die_nomem();
    if (!stralloc_0(&cookie)) die_nomem();
    if (!stralloc_copys(&srshost,"")) die_nomem();
    if (*sendhost) {
      j = str_len(sendhost);
      if (sendhost[j - 1] == '.') {
        if (!stralloc_copys(&srshost,sendhost)) die_nomem();
        if (!stralloc_cats(&srshost,host)) die_nomem();
      } else
        if (!stralloc_copys(&srshost,sendhost)) die_nomem();
    } else
      if (!stralloc_copys(&srshost,host)) die_nomem();
    if (!stralloc_0(&srshost)) die_nomem();
  } else
    die_control();

  /* Let's go SRS rewrite */

  srs = srs_new();

  if (separator == '-' || separator == '+' || separator == '=') {    // '=' is default
    r = srs_set_separator(srs,separator);
    if (r != SRS_SUCCESS) return srserror_str(r);
  }
  if (alwaysrewrite) {
    r = srs_set_alwaysrewrite(srs,alwaysrewrite);
    if (r != SRS_SUCCESS) return srserror_str(r);
  }

  for (j = 0, i = 0; j < cookie.len; j++) {
    if (cookie.s[j] == ' ' || cookie.s[j] == '\0' ) { 
      cookie.s[j] = '\0'; 
      r = srs_add_secret(srs,cookie.s + i);
      if (r != SRS_SUCCESS) return srserror_str(r);
      i = j + 1; 
      if (cookie.s[i] == ' ') { j++; continue; }
    }
  }

  if ((r = srs_forward(srs,srssender,sizeof(srssender),sender,srshost.s)) != SRS_SUCCESS)
    logmsg(WHO,100,FATAL,B("Unable to forward: ",sender," ",srs_strerror(r)));

  if (qmail_open(&qqt) == -1)
    logmsg(WHO,111,FATAL,"unable to fork: ");
  qmail_puts(&qqt,dtline);
  if (buffer_copy(&bo,&bi) != 0)
    logmsg(WHO,111,FATAL,"unable to read message: ");
  buffer_flush(&bo);

  num[fmt_ulong(num,qmail_qp(&qqt))] = 0;
 
  qmail_from(&qqt,srssender);
  while (*++argv) qmail_to(&qqt,*argv);
  qqx = qmail_close(&qqt);
  if (*qqx) logmsg(WHO,*qqx == 'D' ? 100 : 111,FATAL,qqx + 1);
  logmsg(WHO,0,LOG,B(srssender,": qp ",num));

}