#include "idle.h"

#include <stdlib.h>
#include <time.h>

#include "mailimap_sender.h"
#include "mailimap_parser.h"
#include "mailimap.h"

static int mailimap_idle_send(mailimap * session)
{
  int r;
  
  r = mailimap_token_send(session->imap_stream, "IDLE");
  if (r != MAILIMAP_NO_ERROR)
    return r;

  return MAILIMAP_NO_ERROR;
}

static int mailimap_done_send(mailimap * session)
{
  int r;
  
  r = mailimap_token_send(session->imap_stream, "DONE");
  if (r != MAILIMAP_NO_ERROR)
    return r;

  return MAILIMAP_NO_ERROR;
}

LIBETPAN_EXPORT
int mailimap_idle(mailimap * session)
{
  int r;
  size_t index;
  struct mailimap_continue_req * cont_req;
  struct mailimap_response * response;
  
  session->imap_idle_timestamp = time(NULL);
  
  r = mailimap_send_current_tag(session);
  if (r != MAILIMAP_NO_ERROR)
	return r;
  
  r = mailimap_idle_send(session);
  if (r != MAILIMAP_NO_ERROR)
	return r;
  
  r = mailimap_crlf_send(session->imap_stream);
  if (r != MAILIMAP_NO_ERROR)
	return r;

  if (mailstream_flush(session->imap_stream) == -1)
    return MAILIMAP_ERROR_STREAM;
  
  if (mailimap_read_line(session) == NULL)
    return MAILIMAP_ERROR_STREAM;
  
  index = 0;

  r = mailimap_continue_req_parse(session->imap_stream,
      session->imap_stream_buffer,
      &index, &cont_req,
      session->imap_progr_rate, session->imap_progr_fun);
  
  if (r == MAILIMAP_NO_ERROR)
    mailimap_continue_req_free(cont_req);

  if (r == MAILIMAP_ERROR_PARSE) {
    r = mailimap_parse_response(session, &response);
    if (r != MAILIMAP_NO_ERROR)
      return r;
    mailimap_response_free(response);
    
    return MAILIMAP_ERROR_EXTENSION;
  }
  
  return MAILIMAP_NO_ERROR;
}

LIBETPAN_EXPORT
int mailimap_idle_done(mailimap * session)
{
  int r;
  int error_code;
  struct mailimap_response * response;
  
  r = mailimap_done_send(session);
  if (r != MAILIMAP_NO_ERROR)
	return r;
  
  r = mailimap_crlf_send(session->imap_stream);
  if (r != MAILIMAP_NO_ERROR)
	return r;

  if (mailstream_flush(session->imap_stream) == -1)
    return MAILIMAP_ERROR_STREAM;
  
  if (mailimap_read_line(session) == NULL)
    return MAILIMAP_ERROR_STREAM;
  
  r = mailimap_parse_response(session, &response);
  if (r != MAILIMAP_NO_ERROR)
    return r;
  
  error_code = response->rsp_resp_done->rsp_data.rsp_tagged->rsp_cond_state->rsp_type;

  mailimap_response_free(response);

  switch (error_code) {
  case MAILIMAP_RESP_COND_STATE_OK:
    return MAILIMAP_NO_ERROR;

  default:
    return MAILIMAP_ERROR_EXTENSION;
  }
}

LIBETPAN_EXPORT
int mailimap_idle_get_fd(mailimap * session)
{
  mailstream_low * low;
  
  low = mailstream_get_low(session->imap_stream);
  return mailstream_low_get_fd(low);
}

LIBETPAN_EXPORT
void mailimap_idle_set_delay(mailimap * session, long delay)
{
  session->imap_idle_maxdelay = delay;
}

LIBETPAN_EXPORT
long mailimap_idle_get_done_date(mailimap * session)
{
  time_t current_time;
  time_t next_date;
  
  current_time = time(NULL);
  next_date = session->imap_idle_timestamp + session->imap_idle_maxdelay;
  
  if (current_time >= next_date)
    return 0;
  
  return next_date - current_time;
}

LIBETPAN_EXPORT
int mailimap_check_idle(mailimap * session)
{
  int send_done;
  int r;
  
  send_done = 0;
  if (mailimap_idle_get_done_date(session) == 0) {
    send_done = 1;
  }
  else {
    int fd;
    fd_set fd_read;
    struct timeval timeout;
    
    fd = mailimap_idle_get_fd(session);
    if (fd < 0)
      return MAILIMAP_ERROR_STREAM;
    
    timeout.tv_sec = 0;
    timeout.tv_usec = 0;
    FD_ZERO(&fd_read);
    FD_SET(fd, &fd_read);
    r = select(fd + 1, &fd_read, NULL, NULL, &timeout);
    if (r > 0)
      send_done = 1;
  }
  
  if (send_done) {
    r = mailimap_idle_done(session);
    if (r != MAILIMAP_NO_ERROR)
      return r;
    
    r = mailimap_idle(session);
    if (r != MAILIMAP_NO_ERROR)
      return r;
  }
  
  return MAILIMAP_NO_ERROR;
}

LIBETPAN_EXPORT
int mailimap_has_idle(mailimap * session)
{
  return mailimap_has_extension(session, "IDLE");
}