/*
     This file is part of GNUnet.
     Copyright (C) 2011 GNUnet e.V.

     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     or (at your option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Affero General Public License for more details.

     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */

/**
 * @file util/test_common_logging_runtime_loglevels.c
 * @brief testcase for the logging module  (runtime log level adjustment)
 * @author LRN
 */

#include "platform.h"
#include "gnunet_util_lib.h"

#define VERBOSE GNUNET_NO

/**
 * How much time the child is allowed to waste on skipped log calls, at most.
 * Raspberry Pi takes 113 microseconds tops, this is 3x that value.
 */
#define MAX_SKIP_DELAY GNUNET_TIME_relative_multiply ( \
          GNUNET_TIME_UNIT_MICROSECONDS, 400).rel_value_us

/**
 * How much time non-skipped log call should take, at least.
 * Keep in sync with the value in the dummy!
 */
#define OUTPUT_DELAY GNUNET_TIME_relative_multiply ( \
          GNUNET_TIME_UNIT_MICROSECONDS, 1000).rel_value_us

static int ok;

static int phase = 0;

static struct GNUNET_OS_Process *proc;

/* Pipe to read from started processes stdout (on read end) */
static struct GNUNET_DISK_PipeHandle *pipe_stdout;

static struct GNUNET_SCHEDULER_Task *die_task;

static struct GNUNET_SCHEDULER_Task *read_task;

static void
runone (void);


static void
end_task (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Ending phase %d, ok is %d\n", phase,
              ok);
  if (NULL != proc)
  {
    if (0 != GNUNET_OS_process_kill (proc, GNUNET_TERM_SIG))
    {
      GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "kill");
    }
    GNUNET_OS_process_wait (proc);
    GNUNET_OS_process_destroy (proc);
    proc = NULL;
  }
  if (NULL != read_task)
  {
    GNUNET_SCHEDULER_cancel (read_task);
    read_task = NULL;
  }
  GNUNET_DISK_pipe_close (pipe_stdout);
  if (ok == 1)
  {
    if (phase < 9)
    {
      phase += 1;
      runone ();
    }
    else
      ok = 0;
  }
  else
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "failing\n");
}


static char *
read_output_line (int phase_from1, int phase_to1, int phase_from2,
                  int phase_to2, char c, const char *expect_level,
                  long delay_morethan, long delay_lessthan, int phasecur,
                  char *p,
                  int *len, long *delay, char level[8])
{
  char *r = p;
  char t[7];
  int i, j, stop = 0;
  int level_matches;
  int delay_is_sane;
  int delay_is_a_dummy;
  int delay_outside_of_range;
  int stage = 0;

  j = 0;

  if (! ((phasecur >= phase_from1) && (phasecur <= phase_to1)) &&
      ! ((phasecur >= phase_from2) && (phasecur <= phase_to2)))
    return p;
#if 0
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Trying to match '%c%s \\d\\r\\n' on %s\n", c, expect_level, p);
#endif
  for (i = 0; i < *len && ! stop; i++)
  {
    switch (stage)
    {
    case 0:                    /* read first char */
      if (r[i] != c)
      {
        GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Expected '%c', but got '%c'\n", c,
                    r[i]);
        GNUNET_break (0);
        return NULL;
      }
      stage += 1;
      break;

    case 1:                    /* read at most 7 char-long error level string, finished by ' ' */
      if (r[i] == ' ')
      {
        level[j] = '\0';
        stage += 1;
        j = 0;
      }
      else if (i == 8)
      {
        GNUNET_break (0);
        ok = 2;
        return NULL;
      }
      else
        level[j++] = r[i];
      break;

    case 2:                    /* read the delay, finished by '\n' */
      t[j++] = r[i];
      if (r[i] == '\n')
      {
        t[j - 1] = '\0';
        *delay = strtol (t, NULL, 10);
        stop = 1;
      }
      break;
    }
  }
  level_matches = (strcmp (expect_level, level) == 0);
  delay_is_sane = (*delay >= 0) && (*delay <= 1000000);
  delay_is_a_dummy = (c == 'L');
  /* Delay must be either less than 'lessthan' (log call is skipped)
   * or more than 'morethan' (log call is not skipped)
   */
  delay_outside_of_range = ((*delay < delay_lessthan) || (*delay >=
                                                          delay_morethan));
  if (delay_is_a_dummy)
    delay_outside_of_range = 1;

  if (! stop)
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Wrong log format?\n");
  if (! level_matches)
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Wrong log level\n");
  if (! delay_is_sane)
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Delay %ld is insane\n",
                *delay);
  if (! delay_outside_of_range)
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Delay %ld is not outside of range (%ld ; %ld)\n",
                *delay,
                delay_lessthan,
                delay_morethan);
  if (! stop || ! level_matches || ! delay_is_sane || ! delay_outside_of_range)
    return NULL;
  *len = *len - i;
  return &r[i];
}


/**
 * Up to 8 non-skipped GNUNET_log() calls
 * + extra line with delay for each one
 */
#define LOG_MAX_NUM_LINES (8 * 2)
/**
 * Actual message is 17 chars at most
 */
#define LOG_MAX_LINE_LENGTH (17)

#define LOG_BUFFER_SIZE LOG_MAX_NUM_LINES *LOG_MAX_LINE_LENGTH

static char buf[LOG_BUFFER_SIZE];

static char *buf_ptr;

static int bytes;


static void
read_call (void *cls)
{
  const struct GNUNET_DISK_FileHandle *stdout_read_handle = cls;
  char level[8];
  long delay;
  long delays[8];
  int rd;

  read_task = NULL;
  rd = GNUNET_DISK_file_read (stdout_read_handle, buf_ptr,
                              sizeof(buf) - bytes);
  if (rd > 0)
  {
    buf_ptr += rd;
    bytes += rd;
#if VERBOSE
    fprintf (stderr, "got %d bytes, reading more\n", rd);
#endif
    read_task = GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
                                                stdout_read_handle,
                                                &read_call,
                                                (void *) stdout_read_handle);
    return;
  }

#if VERBOSE
  fprintf (stderr, "bytes is %d:%s\n", bytes, buf);
#endif

  /* +------CHILD OUTPUT--
   * |      SOFT     HARD
   * |    E W I D  E W I D
   * | 0E *        * *
   * | 1W * *      * *
   * P 2I * * *    * *
   * H 3D * * * *  * *
   * A
   * S 4E *        *
   * E 5W * *      * *
   * | 6I * * *    * * *
   * | 7D * * * *  * * * *
   * | 8  * *      * *
   * | 9  * *      * *
   */
  {
    char *p = buf;

    if ((bytes == LOG_BUFFER_SIZE) ||
        ! (p =
             read_output_line (0, 3, 4, 9, 'L', "ERROR", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '1', "ERROR", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[0], level)) ||
        ! (p =
             read_output_line (1, 3, 5, 9, 'L', "WARNING", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '1', "WARNING", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[1], level)) ||
        ! (p =
             read_output_line (2, 3, 6, 7, 'L', "INFO", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '1', "INFO", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[2], level)) ||
        ! (p =
             read_output_line (3, 3, 7, 7, 'L', "DEBUG", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '1', "DEBUG", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[3], level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, 'L', "ERROR", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '2', "ERROR", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[4], level)) ||
        ! (p =
             read_output_line (0, 3, 5, 9, 'L', "WARNING", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '2', "WARNING", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[5], level)) ||
        ! (p =
             read_output_line (-1, -1, 6, 7, 'L', "INFO", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '2', "INFO", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[6], level)) ||
        ! (p =
             read_output_line (-1, -1, 7, 7, 'L', "DEBUG", -1,
                               1, phase, p,
                               &bytes, &delay, level)) ||
        ! (p =
             read_output_line (0, 3, 4, 9, '2', "DEBUG", OUTPUT_DELAY,
                               MAX_SKIP_DELAY, phase, p,
                               &bytes, &delays[7], level)))
    {
      if (bytes == LOG_BUFFER_SIZE)
        fprintf (stderr, "%s", "Ran out of buffer space!\n");
      GNUNET_break (0);
      ok = 2;
      GNUNET_SCHEDULER_cancel (die_task);
      GNUNET_SCHEDULER_add_now (&end_task, NULL);
      return;
    }
  }
  GNUNET_SCHEDULER_cancel (die_task);
  GNUNET_SCHEDULER_add_now (&end_task, NULL);
}


static void
runone ()
{
  const struct GNUNET_DISK_FileHandle *stdout_read_handle;

  pipe_stdout = GNUNET_DISK_pipe (GNUNET_DISK_PF_BLOCKING_RW);

  if (pipe_stdout == NULL)
  {
    GNUNET_break (0);
    ok = 2;
    return;
  }

  putenv ((char*) "GNUNET_LOG=");
  putenv ((char*) "GNUNET_FORCE_LOG=");
  putenv ((char*) "GNUNET_FORCE_LOGFILE=");
  switch (phase)
  {
  case 0:
    putenv ((char*) "GNUNET_LOG=;;;;ERROR");
    break;

  case 1:
    putenv ((char*) "GNUNET_LOG=;;;;WARNING");
    break;

  case 2:
    putenv ((char*) "GNUNET_LOG=;;;;INFO");
    break;

  case 3:
    putenv ((char*) "GNUNET_LOG=;;;;DEBUG");
    break;

  case 4:
    putenv ((char*) "GNUNET_FORCE_LOG=;;;;ERROR");
    break;

  case 5:
    putenv ((char*) "GNUNET_FORCE_LOG=;;;;WARNING");
    break;

  case 6:
    putenv ((char*) "GNUNET_FORCE_LOG=;;;;INFO");
    break;

  case 7:
    putenv ((char*) "GNUNET_FORCE_LOG=;;;;DEBUG");
    break;

  case 8:
    putenv ((char*) "GNUNET_LOG=blah;;;;ERROR");
    break;

  case 9:
    putenv ((char*) "GNUNET_FORCE_LOG=blah;;;;ERROR");
    break;
  }

  proc = GNUNET_OS_start_process (GNUNET_OS_INHERIT_STD_OUT_AND_ERR,
                                  NULL, pipe_stdout, NULL,
                                  "./test_common_logging_dummy",
                                  "test_common_logging_dummy", NULL);
  GNUNET_assert (NULL != proc);
  putenv ((char*) "GNUNET_FORCE_LOG=");
  putenv ((char*) "GNUNET_LOG=");

  /* Close the write end of the read pipe */
  GNUNET_DISK_pipe_close_end (pipe_stdout, GNUNET_DISK_PIPE_END_WRITE);

  stdout_read_handle =
    GNUNET_DISK_pipe_handle (pipe_stdout, GNUNET_DISK_PIPE_END_READ);

  die_task =
    GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply
                                    (GNUNET_TIME_UNIT_SECONDS, 10),
                                  &end_task,
                                  NULL);

  bytes = 0;
  buf_ptr = buf;
  memset (&buf, 0, sizeof(buf));

  read_task = GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
                                              stdout_read_handle,
                                              &read_call,
                                              (void *) stdout_read_handle);
}


static void
task (void *cls)
{
  phase = 0;
  runone ();
}


int
main (int argc, char *argv[])
{
  GNUNET_log_setup ("test-common-logging-runtime-loglevels",
                    "WARNING",
                    NULL);
  ok = 1;
  GNUNET_SCHEDULER_run (&task, &ok);
  return ok;
}


/* end of test_common_logging_runtime_loglevels.c */
