#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <pwd.h>

#ifdef HAVE_SYSTEMD
# include <systemd/sd-daemon.h>
#endif

#ifdef HAVE_WS2TCPIP_H
# include <ws2tcpip.h>
#endif

#include <Ecore.h>
#include <ecore_private.h>

#include "Ecore_Con.h"
#include "ecore_con_private.h"

#define LENGTH_OF_SOCKADDR_UN(s)                (strlen((s)->sun_path) +                 \
                                                 (size_t)(((struct sockaddr_un *)NULL)-> \
                                                          sun_path))
#define LENGTH_OF_ABSTRACT_SOCKADDR_UN(s, path) (strlen(path) + 1 +            \
                                                 (size_t)(((struct sockaddr_un \
                                                            *)NULL)->sun_path))

static int _ecore_con_local_init_count = 0;

static const char *_ecore_con_local_path_get()
{
   const char *homedir = getenv("XDG_RUNTIME_DIR");
   if (!homedir) homedir = eina_environment_home_get();
   if (!homedir) homedir = eina_environment_tmp_get();

   return homedir;
}

int
ecore_con_local_init(void)
{
   if (++_ecore_con_local_init_count != 1)
     return _ecore_con_local_init_count;

   return _ecore_con_local_init_count;
}

int
ecore_con_local_shutdown(void)
{
   if (--_ecore_con_local_init_count != 0)
     return _ecore_con_local_init_count;

   return _ecore_con_local_init_count;
}

EAPI char *
ecore_con_local_path_new(Eina_Bool is_system, const char *name, int port)
{
   char buf[4096];
   const char *homedir;

   EINA_SAFETY_ON_NULL_RETURN_VAL(name, NULL);

   if (!is_system)
     {
#if defined(HAVE_GETUID) && defined(HAVE_GETEUID)
        if (getuid() == geteuid())
#endif
          homedir = _ecore_con_local_path_get();
#if defined(HAVE_GETUID) && defined(HAVE_GETEUID)
        else
          {
             struct passwd *pw = getpwent();

             if ((!pw) || (!pw->pw_dir)) homedir = "/tmp";
             else homedir = pw->pw_dir;
          }
#endif

        if (port < 0)
           snprintf(buf, sizeof(buf), "%s/.ecore/%s",
                    homedir, name);
        else
           snprintf(buf, sizeof(buf), "%s/.ecore/%s/%i",
                    homedir, name, port);
        return strdup(buf);
     }
   else
     {
        if (port < 0)
          {
             if (name[0] == '/')
               return strdup(name);
             else
               {
                  homedir = eina_environment_tmp_get();
                  snprintf(buf, sizeof(buf), "%s/.ecore_service|%s",
                           homedir, name);
                  return strdup(buf);
               }
          }
        else
          {
             if (name[0] == '/')
               snprintf(buf, sizeof(buf), "%s|%i", name, port);
             else
               {
                  homedir = eina_environment_tmp_get();
                  snprintf(buf, sizeof(buf), "%s/.ecore_service|%s|%i",
                           homedir, name, port);
               }
             return strdup(buf);
          }
     }
}

int
ecore_con_local_connect(Ecore_Con_Server *obj,
                        Eina_Bool (*cb_done)(void *data, Ecore_Fd_Handler *fd_handler),
                        void *data EINA_UNUSED)
{
#ifndef HAVE_LOCAL_SOCKETS
   return 0;
#else
   Efl_Network_Server_Data *svr = efl_data_scope_get(obj, EFL_NETWORK_SERVER_CLASS);
   char *buf = NULL;
   struct sockaddr_un socket_unix;
   int curstate = 0;
   int socket_unix_len;

   if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_USER)
     {
        buf = ecore_con_local_path_new(EINA_FALSE, svr->name, svr->port);
     }
   else if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_SYSTEM)
     {
        buf = ecore_con_local_path_new(EINA_TRUE, svr->name, svr->port);
     }
   else if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_ABSTRACT)
     {
        buf = strdup(svr->name);
     }

   EINA_SAFETY_ON_NULL_RETURN_VAL(buf, 0);

   svr->fd = socket(AF_UNIX, SOCK_STREAM, 0);
   if (svr->fd < 0)
     {
        free(buf);
        return 0;
     }

   if (fcntl(svr->fd, F_SETFL, O_NONBLOCK) < 0)
     goto error;

   if (fcntl(svr->fd, F_SETFD, FD_CLOEXEC) < 0)
     goto error;

   if (setsockopt(svr->fd, SOL_SOCKET, SO_REUSEADDR, (const void *)&curstate,
                  sizeof(curstate)) < 0)
     goto error;

   socket_unix.sun_family = AF_UNIX;

   if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_ABSTRACT)
     {
#ifdef HAVE_ABSTRACT_SOCKETS
        /* copy name insto sun_path, prefixed by null to indicate abstract namespace */
        snprintf(socket_unix.sun_path, sizeof(socket_unix.sun_path), ".%s",
                 svr->name);
        socket_unix.sun_path[0] = '\0';
        socket_unix_len = LENGTH_OF_ABSTRACT_SOCKADDR_UN(&socket_unix,
                                                         svr->name);
#else
        WRN("Your system does not support abstract sockets!");
        goto error;
#endif
     }
   else
     {
        strncpy(socket_unix.sun_path, buf, sizeof(socket_unix.sun_path) - 1);
        socket_unix.sun_path[sizeof(socket_unix.sun_path) - 1] = '\0';
        socket_unix_len = LENGTH_OF_SOCKADDR_UN(&socket_unix);
     }

   if (connect(svr->fd, (struct sockaddr *)&socket_unix,
               socket_unix_len) < 0)
     {
        DBG("local connection failed: %s", strerror(errno));
        goto error;
     }

   svr->path = buf;
   buf = NULL;

   if (svr->type & ECORE_CON_SSL)
     {
        if (!ecore_con_ssl_server_init(obj)) ERR("Can't init SSL");
     }

   svr->fd_handler =
     ecore_main_fd_handler_add(svr->fd, ECORE_FD_READ,
                               cb_done, obj, NULL, NULL);
   if (!svr->fd_handler)
     goto error;

   if (!svr->delete_me) ecore_con_event_server_add(obj);

   free(buf);

   return 1;
error:
   if (svr->fd) close(svr->fd);
   svr->fd = -1;
   free(buf);
   return 0;
#endif
}

#ifdef HAVE_LOCAL_SOCKETS
static void
_ecore_con_local_mkpath(const char *path, mode_t mode)
{
   char *s, *d, *itr;

   if (!path) return;
   EINA_SAFETY_ON_TRUE_RETURN(path[0] != '/');

   s = strdup(path);
   EINA_SAFETY_ON_NULL_RETURN(s);
   d = dirname(s);
   EINA_SAFETY_ON_NULL_RETURN(d);

   for (itr = d + 1; *itr != '\0'; itr++)
     {
        if (*itr == '/')
          {
             *itr = '\0';
             if (mkdir(d, mode) != 0)
               {
                  if (errno != EEXIST)
                    {
                       ERR("could not create parent directory '%s' of path '%s': %s", d, path, strerror(errno));
                       goto end;
                    }
               }
             *itr = '/';
          }
     }

   if (mkdir(d, mode) != 0)
     {
        if (errno != EEXIST)
          ERR("could not create parent directory '%s' of path '%s': %s", d, path, strerror(errno));
        else
          {
             struct stat st;
             if ((stat(d, &st) != 0) || (!S_ISDIR(st.st_mode)))
               ERR("could not create parent directory '%s' of path '%s': exists but is not a directory", d, path);
          }
     }

 end:
   free(s);
}
#endif

int
ecore_con_local_listen(
  Ecore_Con_Server *obj,
  Eina_Bool (*
             cb_listen)(void *data,
                        Ecore_Fd_Handler *
                        fd_handler),
  void *data
  EINA_UNUSED)
{
#ifdef HAVE_LOCAL_SOCKETS
   Efl_Network_Server_Data *svr = efl_data_scope_get(obj, EFL_NETWORK_SERVER_CLASS);
   char *buf = NULL;
   struct sockaddr_un socket_unix;
   struct linger lin;
   mode_t pmode;
   mode_t mask;
   int socket_unix_len;
   Eina_Bool abstract_socket;

   mask = S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH | S_IWOTH | S_IXOTH;

   if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_USER)
     {
        buf = ecore_con_local_path_new(EINA_FALSE, svr->name, svr->port);

        mask = S_IRUSR | S_IWUSR | S_IXUSR;
        _ecore_con_local_mkpath(buf, mask);

        mask = S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH | S_IWOTH | S_IXOTH;
     }
   else if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_SYSTEM)
     {
        mask = 0;
        buf = ecore_con_local_path_new(EINA_TRUE, svr->name, svr->port);
     }
   else if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_ABSTRACT)
     {
        buf = strdup(svr->name);
     }

   EINA_SAFETY_ON_NULL_RETURN_VAL(buf, 0);

   pmode = umask(mask);
start:
   socket_unix.sun_family = AF_UNIX;
   if ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_ABSTRACT)
     {
        abstract_socket = EINA_TRUE;
#ifdef HAVE_ABSTRACT_SOCKETS
        /* . is a placeholder */
        snprintf(socket_unix.sun_path, sizeof(socket_unix.sun_path), ".%s",
                 svr->name);
        /* first char null indicates abstract namespace */
        socket_unix.sun_path[0] = '\0';
        socket_unix_len = LENGTH_OF_ABSTRACT_SOCKADDR_UN(&socket_unix,
                                                         svr->name);
#else
        ERR("Your system does not support abstract sockets!");
        goto error_umask;
#endif
     }
   else
     {
        abstract_socket = EINA_FALSE;
        strncpy(socket_unix.sun_path, buf, sizeof(socket_unix.sun_path) - 1);
        socket_unix.sun_path[sizeof(socket_unix.sun_path) - 1] = '\0';
        socket_unix_len = LENGTH_OF_SOCKADDR_UN(&socket_unix);
     }

#ifdef HAVE_SYSTEMD
   if (svr->type & ECORE_CON_SOCKET_ACTIVATE && sd_fd_index < sd_fd_max)
     {
        if (sd_is_socket_unix(SD_LISTEN_FDS_START + sd_fd_index,
                              SOCK_STREAM, 1,
                              socket_unix.sun_path,
                              abstract_socket ? socket_unix_len : 0) <= 0)
          {
             ERR("Your systemd unit seems to provide fd in the wrong order for Socket activation.");
             goto error_umask;
          }
        svr->fd = SD_LISTEN_FDS_START + sd_fd_index++;

        if (fcntl(svr->fd, F_SETFL, O_NONBLOCK) < 0)
          goto error_umask;

        lin.l_onoff = 1;
        lin.l_linger = 0;
        if (setsockopt(svr->fd, SOL_SOCKET, SO_LINGER, (const void *)&lin,
                       sizeof(struct linger)) < 0)
          goto error_umask;

        goto fd_ready;
     }
#else
   (void)abstract_socket;
#endif
   svr->fd = socket(AF_UNIX, SOCK_STREAM, 0);
   if (svr->fd < 0)
     goto error_umask;

   if (fcntl(svr->fd, F_SETFL, O_NONBLOCK) < 0)
     goto error_fd;

   if (fcntl(svr->fd, F_SETFD, FD_CLOEXEC) < 0)
     goto error_fd;

   lin.l_onoff = 1;
   lin.l_linger = 0;
   if (setsockopt(svr->fd, SOL_SOCKET, SO_LINGER, (const void *)&lin,
                  sizeof(struct linger)) < 0)
     goto error_fd;

   if (bind(svr->fd, (struct sockaddr *)&socket_unix, socket_unix_len) < 0)
     {
        DBG("Local socket '%s' bind failed: %s", buf, strerror(errno));
        if ((((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_USER) ||
             ((svr->type & ECORE_CON_TYPE) == ECORE_CON_LOCAL_SYSTEM)) &&
            (connect(svr->fd, (struct sockaddr *)&socket_unix,
                     socket_unix_len) < 0))
          {
             DBG("Local socket '%s' connect test failed: %s", buf, strerror(errno));
             if (unlink(buf) >= 0)
               goto start;
             else
               {
                  DBG("Local socket '%s' removal failed: %s", buf, strerror(errno));
                  goto error_fd;
               }
          }
     }

   if (listen(svr->fd, 4096) < 0)
     goto error_fd;

#ifdef HAVE_SYSTEMD
fd_ready:
#endif
   svr->path = buf;
   buf = NULL;

   svr->fd_handler =
     ecore_main_fd_handler_add(svr->fd, ECORE_FD_READ,
                               cb_listen, obj, NULL, NULL);
   umask(pmode);
   if (!svr->fd_handler)
     goto error;

   free(buf);

   return 1;

error_fd:
   close(svr->fd);
   svr->fd = -1;
error_umask:
   umask(pmode);
error:
   free(buf);
#endif /* HAVE_LOCAL_SOCKETS */
   return 0;
}