#include "sgetopt.h"
#include "substdio.h"
#include "readwrite.h"
#include "stralloc.h"
#include "getln.h"
#include "strerr.h"
#include "error.h"
#include "exit.h"
#include "open.h"
#include "wait.h"
#include "seek.h"
#include "env.h"
#include "str.h"
#include "fmt.h"
#include "token822.h"
#include "control.h"
#include "qmail.h"
#include "auto_qmail.h"

#define FATAL "dot-forward: fatal: "
#define INFO "dot-forward: info: "

void die_nomem()
{ strerr_die2x(111,FATAL,"out of memory"); }
void die_control()
{ strerr_die2sys(111,FATAL,"unable to read controls: "); }
void die_qq()
{ strerr_die2sys(111,FATAL,"unable to run qq: "); }
void die_readmess()
{ strerr_die2sys(111,FATAL,"unable to read message: "); }

stralloc line = {0};

void die_parse()
{
  if (!stralloc_0(&line)) die_nomem();
  strerr_die3x(111,FATAL,"unable to parse this line: ",line.s);
}

int flagdoit = 1;
int flagacted;
int flagdirect;

char *ufline;
char *rpline;
char *dtline;
char *sender;
char *user;
int userlen;
char *host;
int hostlen;

char messbuf[1024];
substdio ssmess;
char childbuf[1024];
substdio sschild;

int blindwrite(fd,buf,len)
int fd; char *buf; int len;
{
  write(fd,buf,len);
  return len;
}

void run(cmd)
char *cmd;
{
  int child;
  int pi[2];
  char *args[4];
  int wstat;

  if (!flagdoit) {
    strerr_warn2("pipe through ",cmd,0);
    return;
  }

  if (pipe(pi) == -1)
    strerr_die2sys(111,FATAL,"unable to create pipe: ");

  switch (child = fork()) {
    case -1:
      strerr_die2sys(111,FATAL,"unable to fork: ");
    case 0:
      close(pi[1]);
      if (fd_move(0,pi[0]) == -1)
        strerr_die2sys(111,FATAL,"unable to set fd: ");
      args[0] = "/bin/sh"; args[1] = "-c"; args[2] = cmd; args[3] = 0;
      sig_pipedefault();
      execv(*args,args);
      strerr_die2sys(111,FATAL,"unable to run /bin/sh: ");
  }

  close(pi[0]);

  substdio_fdbuf(&ssmess,read,0,messbuf,sizeof messbuf);
  substdio_fdbuf(&sschild,blindwrite,pi[1],childbuf,sizeof childbuf);

  substdio_puts(&sschild,ufline);
  substdio_puts(&sschild,rpline);
  substdio_puts(&sschild,dtline);
  if (substdio_copy(&sschild,&ssmess) != 0) die_readmess();
  substdio_flush(&sschild);

  close(pi[1]);

  wait_pid(&wstat,child);
  if (wait_crashed(wstat))
    strerr_die2x(111,FATAL,"child crashed");

  switch(wait_exitcode(wstat)) {
    case 100:
    case 64: case 65: case 70: case 76: case 77: case 78: case 112:
      _exit(100);
    case 0:
      break;
    default:
      _exit(111);
  }

  if (seek_begin(0) == -1)
    strerr_die2sys(111,FATAL,"unable to rewind input: ");
}

stralloc targets = {0};

stralloc me = {0};
stralloc defaulthost = {0};
stralloc defaultdomain = {0};
stralloc plusdomain = {0};

void readcontrols()
{
  int r;
  int fddir;

  fddir = open_read(".");
  if (fddir == -1)
    strerr_die2sys(111,FATAL,"unable to open current directory: ");

  if (chdir(auto_qmail) == -1)
    strerr_die4sys(111,FATAL,"unable to chdir to ",auto_qmail,": ");

  r = control_readline(&me,"control/me");
  if (r == -1) die_control();
  if (!r) if (!stralloc_copys(&me,"me")) die_nomem();

  r = control_readline(&defaultdomain,"control/defaultdomain");
  if (r == -1) die_control();
  if (!r) if (!stralloc_copy(&defaultdomain,&me)) die_nomem();

  r = control_readline(&defaulthost,"control/defaulthost");
  if (r == -1) die_control();
  if (!r) if (!stralloc_copy(&defaulthost,&me)) die_nomem();

  r = control_readline(&plusdomain,"control/plusdomain");
  if (r == -1) die_control();
  if (!r) if (!stralloc_copy(&plusdomain,&me)) die_nomem();

  if (fchdir(fddir) == -1)
    strerr_die2sys(111,FATAL,"unable to set current directory: ");
}

stralloc cbuf = {0};
token822_alloc toks = {0};
token822_alloc tokaddr = {0};
stralloc address = {0};

void gotaddr()
{
  int i;
  int j;
  int flaghasat;
 
  token822_reverse(&tokaddr);
  if (token822_unquote(&address,&tokaddr) != 1) die_nomem();
 
  flaghasat = 0;
  for (i = 0;i < tokaddr.len;++i)
    if (tokaddr.t[i].type == TOKEN822_AT)
      flaghasat = 1;
 
  tokaddr.len = 0;

  if (!address.len) return;

  if (!flaghasat)
    if (address.len == userlen)
      if (!case_diffb(address.s,address.len,user)) {
        flagacted = 1;
        flagdirect = 1;
        return;
      }

  if (flaghasat)
    if (address.len == userlen + 1 + hostlen)
      if (!case_diffb(address.s,userlen,user))
        if (address.s[userlen] == '@')
          if (!case_diffb(address.s + userlen + 1,hostlen,host)) {
            flagacted = 1;
            flagdirect = 1;
            return;
          }

  if (!flaghasat)
    if (address.s[0] == '/') {
      if (!stralloc_0(&address)) die_nomem();
      strerr_die4x(111,FATAL,"file delivery ",address.s," not supported");
    }

  if (!flaghasat)
    if (address.s[0] == '|') {
      if (!stralloc_0(&address)) die_nomem();
      flagacted = 1;
      run(address.s + 1);
      return;
    }

  if (!flaghasat) {
    if (!stralloc_cats(&address,"@")) die_nomem();
    if (!stralloc_cat(&address,&defaulthost)) die_nomem();
  }
  if (address.s[address.len - 1] == '+') {
    address.s[address.len - 1] = '.';
    if (!stralloc_cat(&address,&plusdomain)) die_nomem();
  }
  j = 0;
  for (i = 0;i < address.len;++i) if (address.s[i] == '@') j = i;
  for (i = j;i < address.len;++i) if (address.s[i] == '.') break;
  if (i == address.len) {
    if (!stralloc_cats(&address,".")) die_nomem();
    if (!stralloc_cat(&address,&defaultdomain)) die_nomem();
  }

  if (!stralloc_0(&address)) die_nomem();

  if (!stralloc_cats(&targets,"T")) die_nomem();
  if (!stralloc_cats(&targets,address.s)) die_nomem();
  if (!stralloc_0(&targets)) die_nomem();

  if (!flagdoit)
    strerr_warn2("forward ",address.s,0);
}

void parseline()
{
  int wordok;
  struct token822 *t;
  struct token822 *beginning;
  int r;

  r = token822_parse(&toks,&line,&cbuf);
  if (r == -1) die_nomem();
  if (r == 0) die_parse();

  beginning = toks.t;
  t = toks.t + toks.len;
  wordok = 1;

  if (!token822_readyplus(&tokaddr,1)) die_nomem();
  tokaddr.len = 0;
 
  while (t > beginning)
    switch((--t)->type) {
      case TOKEN822_SEMI:
        break; /*XXX*/
      case TOKEN822_COLON:
        break; /*XXX*/
      case TOKEN822_RIGHT:
        if (tokaddr.len) gotaddr();
        while ((t > beginning) && (t[-1].type != TOKEN822_LEFT))
          if (!token822_append(&tokaddr,--t)) die_nomem();
        gotaddr();
        if (t <= beginning) die_parse();
        --t;
        while ((t > beginning) && ((t[-1].type == TOKEN822_COMMENT) || (t[-1].type == TOKEN822_ATOM) || (t[-1].type == TOKEN822_QUOTE) || (t[-1].type == TOKEN822_AT) || (t[-1].type == TOKEN822_DOT)))
          --t;
        wordok = 0;
        continue;
      case TOKEN822_ATOM: case TOKEN822_QUOTE: case TOKEN822_LITERAL:
        if (!wordok) if (tokaddr.len) gotaddr();
        wordok = 0;
        if (!token822_append(&tokaddr,t)) die_nomem();
        continue;
      case TOKEN822_COMMENT:
        /* comment is lexically a space; shouldn't affect wordok */
        break;
      case TOKEN822_COMMA:
        if (tokaddr.len) gotaddr();
        wordok = 1;
        break;
      default:
        wordok = 1;
        if (!token822_append(&tokaddr,t)) die_nomem();
        continue;
    }
  if (tokaddr.len) gotaddr();
}

struct qmail qq;
unsigned long qp;
char *qqx;
char strnum[FMT_ULONG];

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

char qqbuf[256];
substdio ssqq = SUBSTDIO_FDBUF(mywrite,-1,qqbuf,sizeof qqbuf);

char inbuf[256];

void try(fn)
char *fn;
{
  int fd;
  int match;
  substdio ss;

  fd = open_read(fn);
  if (fd == -1) {
    if (errno == error_noent) return;
    strerr_die4sys(111,FATAL,"unable to open ",fn,": ");
  }

  if (!stralloc_copys(&targets,"")) die_nomem();
  flagacted = 0;
  flagdirect = 0;

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

  for (;;) {
    if (getln(&ss,&line,&match,'\n') == -1)
      strerr_die4sys(111,FATAL,"unable to read ",fn,": ");
    if (!line.len) break;
    if (line.s[0] != '#') parseline();
    if (!match) break;
  }

  close(fd);

  if (targets.len) {
    flagacted = 1;
    if (flagdoit) {
      if (qmail_open(&qq) == -1)
        strerr_die2sys(111,FATAL,"unable to run qmail-queue: ");
      qp = qmail_qp(&qq);
      qmail_puts(&qq,dtline);

      substdio_fdbuf(&ssmess,read,0,messbuf,sizeof messbuf);
      if (substdio_copy(&ssqq,&ssmess) != 0) die_readmess();
      substdio_flush(&ssqq);

      qmail_from(&qq,sender);
      qmail_put(&qq,targets.s,targets.len);

      qqx = qmail_close(&qq);
      if (*qqx == 'D')
        strerr_die3x(100,FATAL,"unable to forward message: ",qqx + 1);
      if (*qqx)
        strerr_die3x(111,FATAL,"unable to forward message: ",qqx + 1);
      strnum[fmt_ulong(strnum,qp)] = 0;
      strerr_warn3(INFO,"qp ",strnum,0);
    }
  }

  if (flagdirect) {
    if (!flagdoit) strerr_warn1("direct delivery",0);
    _exit(0);
  }
  if (!flagacted) {
    if (!flagdoit) strerr_warn2("skipping empty file ",fn,0);
    return;
  }
  _exit(99);
}

void main(argc,argv)
int argc;
char **argv;
{
  int opt;
  int fddir;

  sig_pipeignore();

  while ((opt = getopt(argc,argv,"nN")) != opteof)
    switch(opt) {
      case 'n':
        flagdoit = 0; break;
      case 'N':
        flagdoit = 1; break;
      default:
        strerr_die1x(100,"dot-forward: usage: dot-forward [ -nN ] file ...");
    }
  argv += optind;

  ufline = env_get("UFLINE"); if (!ufline) ufline = "";
  rpline = env_get("RPLINE"); if (!rpline) rpline = "";
  dtline = env_get("DTLINE"); if (!dtline) dtline = "";
  sender = env_get("NEWSENDER"); if (!sender) sender = "";

  user = env_get("USER"); if (!user) user = "";
  userlen = str_len(user);
  host = env_get("HOST"); if (!host) host = "";
  hostlen = str_len(host);

  readcontrols();

  while (*argv)
    try(*argv++);

  if (!flagdoit) strerr_warn1("direct delivery",0);
  _exit(0);
}