/*
 * This file Copyright (C) 2015-2016 Mnemosyne LLC
 *
 * It may be used under the GNU GPL versions 2 or 3
 * or any future license endorsed by Mnemosyne LLC.
 *
 */

#include <event2/event.h>

#include "transmission.h"
#include "file.h"
#include "net.h"
#include "utils.h"
#include "watchdir.h"

#include "libtransmission-test.h"

/***
****
***/

typedef struct callback_data
{
  tr_watchdir_t        dir;
  char               * name;
  tr_watchdir_status   result;
}
callback_data;

#define CB_DATA_STATIC_INIT { NULL, NULL, 0 }

static struct event_base * ev_base = NULL;

extern struct timeval tr_watchdir_generic_interval;
extern unsigned int   tr_watchdir_retry_limit;
extern struct timeval tr_watchdir_retry_start_interval;
extern struct timeval tr_watchdir_retry_max_interval;

static const struct timeval FIFTY_MSEC       = { 0,  50000 };
static const struct timeval ONE_HUNDRED_MSEC = { 0, 100000 };
static const struct timeval TWO_HUNDRED_MSEC = { 0, 200000 };

static void
process_events (void)
{
  event_base_loopexit (ev_base, &TWO_HUNDRED_MSEC);
  event_base_dispatch (ev_base);
}

static tr_watchdir_status
callback (tr_watchdir_t   dir,
          const char    * name,
          void          * context)
{
  callback_data * const data = context;

  if (data->result != TR_WATCHDIR_RETRY)
    {
      data->dir = dir;

      if (data->name != NULL)
        tr_free (data->name);
      data->name = tr_strdup (name);
    }

  return data->result;
}

static void
reset_callback_data (callback_data      * data,
                     tr_watchdir_status   result)
{
  tr_free (data->name);

  data->dir = NULL;
  data->name = NULL;
  data->result = result;
}

static void
create_file (const char * parent_dir,
             const char * name)
{
  char * const path = tr_buildPath (parent_dir, name, NULL);
  libtest_create_file_with_string_contents (path, "");
  tr_free (path);
}

static void
create_dir (const char * parent_dir,
            const char * name)
{
  char * const path = tr_buildPath (parent_dir, name, NULL);
  tr_sys_dir_create (path, 0, 0700, NULL);
  tr_free (path);
}

static tr_watchdir_t
create_watchdir (const char        * path,
                 tr_watchdir_cb      callback,
                 void              * callback_user_data,
                 struct event_base * event_base)
{
#ifdef WATCHDIR_TEST_FORCE_GENERIC
  const bool force_generic = true;
#else
  const bool force_generic = false;
#endif

  return tr_watchdir_new (path, callback, callback_user_data, event_base, force_generic);
}

/***
****
***/

static int
test_construct (void)
{
  char * const test_dir = libtest_sandbox_create ();
  tr_watchdir_t wd;

  ev_base = event_base_new();

  wd = create_watchdir (test_dir, &callback, NULL, ev_base);
  check (wd != NULL);
  check (tr_sys_path_is_same (test_dir, tr_watchdir_get_path (wd), NULL));

  tr_watchdir_free (wd);

  event_base_free (ev_base);

  libtest_sandbox_destroy (test_dir);
  tr_free (test_dir);
  return 0;
}

static int
test_initial_scan (void)
{
  char * const test_dir = libtest_sandbox_create ();

  ev_base = event_base_new();

  /* Speed up generic implementation */
  tr_watchdir_generic_interval = ONE_HUNDRED_MSEC;

  {
    callback_data wd_data = CB_DATA_STATIC_INIT;
    reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);

    tr_watchdir_t wd = create_watchdir (test_dir, &callback, &wd_data, ev_base);
    check (wd != NULL);

    process_events ();
    check_ptr_eq (NULL, wd_data.dir);
    check_ptr_eq (NULL, wd_data.name);

    tr_watchdir_free (wd);
    reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);
  }

  create_file (test_dir, "test");

  {
    callback_data wd_data = CB_DATA_STATIC_INIT;
    reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);

    tr_watchdir_t wd = create_watchdir (test_dir, &callback, &wd_data, ev_base);
    check (wd != NULL);

    process_events ();
    check_ptr_eq (wd, wd_data.dir);
    check_streq ("test", wd_data.name);

    tr_watchdir_free (wd);
    reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);
  }

  event_base_free (ev_base);

  libtest_sandbox_destroy (test_dir);
  tr_free (test_dir);
  return 0;
}

static int
test_watch (void)
{
  char * const test_dir = libtest_sandbox_create ();
  callback_data wd_data = CB_DATA_STATIC_INIT;
  tr_watchdir_t wd;

  ev_base = event_base_new();

  /* Speed up generic implementation */
  tr_watchdir_generic_interval = ONE_HUNDRED_MSEC;

  reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);
  wd = create_watchdir (test_dir, &callback, &wd_data, ev_base);
  check (wd != NULL);

  process_events ();
  check_ptr_eq (NULL, wd_data.dir);
  check_ptr_eq (NULL, wd_data.name);

  create_file (test_dir, "test");

  process_events ();
  check_ptr_eq (wd, wd_data.dir);
  check_streq ("test", wd_data.name);

  reset_callback_data (&wd_data, TR_WATCHDIR_IGNORE);
  create_file (test_dir, "test2");

  process_events ();
  check_ptr_eq (wd, wd_data.dir);
  check_streq ("test2", wd_data.name);

  reset_callback_data (&wd_data, TR_WATCHDIR_IGNORE);
  create_dir (test_dir, "test3");

  process_events ();
  check_ptr_eq (NULL, wd_data.dir);
  check_ptr_eq (NULL, wd_data.name);

  tr_watchdir_free (wd);
  reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);

  event_base_free (ev_base);

  libtest_sandbox_destroy (test_dir);
  tr_free (test_dir);
  return 0;
}

static int
test_watch_two_dirs (void)
{
  char * const test_dir = libtest_sandbox_create ();
  char * const dir1 = tr_buildPath (test_dir, "a", NULL);
  char * const dir2 = tr_buildPath (test_dir, "b", NULL);
  callback_data wd1_data = CB_DATA_STATIC_INIT, wd2_data = CB_DATA_STATIC_INIT;
  tr_watchdir_t wd1, wd2;

  ev_base = event_base_new();

  /* Speed up generic implementation */
  tr_watchdir_generic_interval = ONE_HUNDRED_MSEC;

  create_dir (dir1, NULL);
  create_dir (dir2, NULL);

  reset_callback_data (&wd1_data, TR_WATCHDIR_ACCEPT);
  wd1 = create_watchdir (dir1, &callback, &wd1_data, ev_base);
  check (wd1 != NULL);

  reset_callback_data (&wd2_data, TR_WATCHDIR_ACCEPT);
  wd2 = create_watchdir (dir2, &callback, &wd2_data, ev_base);
  check (wd2 != NULL);

  process_events ();
  check_ptr_eq (NULL, wd1_data.dir);
  check_ptr_eq (NULL, wd1_data.name);
  check_ptr_eq (NULL, wd2_data.dir);
  check_ptr_eq (NULL, wd2_data.name);

  create_file (dir1, "test");

  process_events ();
  check_ptr_eq (wd1, wd1_data.dir);
  check_streq ("test", wd1_data.name);
  check_ptr_eq (NULL, wd2_data.dir);
  check_ptr_eq (NULL, wd2_data.name);

  reset_callback_data (&wd1_data, TR_WATCHDIR_ACCEPT);
  reset_callback_data (&wd2_data, TR_WATCHDIR_ACCEPT);
  create_file (dir2, "test2");

  process_events ();
  check_ptr_eq (NULL, wd1_data.dir);
  check_ptr_eq (NULL, wd1_data.name);
  check_ptr_eq (wd2, wd2_data.dir);
  check_streq ("test2", wd2_data.name);

  reset_callback_data (&wd1_data, TR_WATCHDIR_IGNORE);
  reset_callback_data (&wd2_data, TR_WATCHDIR_IGNORE);
  create_file (dir1, "test3");
  create_file (dir2, "test4");

  process_events ();
  check_ptr_eq (wd1, wd1_data.dir);
  check_streq ("test3", wd1_data.name);
  check_ptr_eq (wd2, wd2_data.dir);
  check_streq ("test4", wd2_data.name);

  reset_callback_data (&wd1_data, TR_WATCHDIR_ACCEPT);
  reset_callback_data (&wd2_data, TR_WATCHDIR_ACCEPT);
  create_file (dir1, "test5");
  create_dir (dir2, "test5");

  process_events ();
  check_ptr_eq (wd1, wd1_data.dir);
  check_streq ("test5", wd1_data.name);
  check_ptr_eq (NULL, wd2_data.dir);
  check_ptr_eq (NULL, wd2_data.name);

  reset_callback_data (&wd1_data, TR_WATCHDIR_ACCEPT);
  reset_callback_data (&wd2_data, TR_WATCHDIR_ACCEPT);
  create_dir (dir1, "test6");
  create_file (dir2, "test6");

  process_events ();
  check_ptr_eq (NULL, wd1_data.dir);
  check_ptr_eq (NULL, wd1_data.name);
  check_ptr_eq (wd2, wd2_data.dir);
  check_streq ("test6", wd2_data.name);

  reset_callback_data (&wd1_data, TR_WATCHDIR_ACCEPT);
  reset_callback_data (&wd2_data, TR_WATCHDIR_ACCEPT);
  create_dir (dir1, "test7");
  create_dir (dir2, "test7");

  process_events ();
  check_ptr_eq (NULL, wd1_data.dir);
  check_ptr_eq (NULL, wd1_data.name);
  check_ptr_eq (NULL, wd2_data.dir);
  check_ptr_eq (NULL, wd2_data.name);

  tr_watchdir_free (wd2);
  reset_callback_data (&wd2_data, TR_WATCHDIR_ACCEPT);

  tr_watchdir_free (wd1);
  reset_callback_data (&wd1_data, TR_WATCHDIR_ACCEPT);

  event_base_free (ev_base);

  tr_free (dir2);
  tr_free (dir1);
  libtest_sandbox_destroy (test_dir);
  tr_free (test_dir);
  return 0;
}

static int
test_retry (void)
{
  char * const test_dir = libtest_sandbox_create ();
  callback_data wd_data = CB_DATA_STATIC_INIT;
  tr_watchdir_t wd;

  ev_base = event_base_new();

  /* Speed up generic implementation */
  tr_watchdir_generic_interval = ONE_HUNDRED_MSEC;

  /* Tune retry logic */
  tr_watchdir_retry_limit = 10;
  tr_watchdir_retry_start_interval = FIFTY_MSEC;
  tr_watchdir_retry_max_interval = tr_watchdir_retry_start_interval;

  reset_callback_data (&wd_data, TR_WATCHDIR_RETRY);
  wd = create_watchdir (test_dir, &callback, &wd_data, ev_base);
  check (wd != NULL);

  process_events ();
  check_ptr_eq (NULL, wd_data.dir);
  check_ptr_eq (NULL, wd_data.name);

  create_file (test_dir, "test");

  process_events ();
  check_ptr_eq (NULL, wd_data.dir);
  check_ptr_eq (NULL, wd_data.name);

  reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);

  process_events ();
  check_ptr_eq (wd, wd_data.dir);
  check_streq ("test", wd_data.name);

  tr_watchdir_free (wd);
  reset_callback_data (&wd_data, TR_WATCHDIR_ACCEPT);

  event_base_free (ev_base);

  libtest_sandbox_destroy (test_dir);
  tr_free (test_dir);
  return 0;
}

/***
****
***/

int
main (void)
{
  const testFunc tests[] = { test_construct,
                             test_initial_scan,
                             test_watch,
                             test_watch_two_dirs,
                             test_retry };

  tr_net_init ();

  return runTests (tests, NUM_TESTS (tests));
}