/* Copyright (c) 2011, 2024, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is designed to work with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have either included with
   the program or referenced in the documentation.

   This program 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 General Public License, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#include <stddef.h>
#include <memory>
#include <unordered_map>
#include <utility>

#include "map_helpers.h"
#include "my_dbug.h"
#include "my_inttypes.h"
#include "my_sys.h"
#include "my_thread_local.h"
#include "mysql/service_mysql_alloc.h"
#include "prealloced_array.h"
#include "sql/psi_memory_key.h"
#include "sql/rpl_gtid.h"

Owned_gtids::Owned_gtids(Checkable_rwlock *_tsid_lock)
    : tsid_lock(_tsid_lock),
      sidno_to_hash(key_memory_Owned_gtids_sidno_to_hash) {}

Owned_gtids::~Owned_gtids() {
  // destructor should only be called when no other thread may access object
  // tsid_lock->assert_no_lock();
  // need to hold lock before calling get_max_sidno
  tsid_lock->rdlock();
  rpl_sidno max_sidno = get_max_sidno();
  for (int sidno = 1; sidno <= max_sidno; sidno++) {
    delete get_hash(sidno);
  }
  tsid_lock->unlock();
  // tsid_lock->assert_no_lock();
}

enum_return_status Owned_gtids::ensure_sidno(rpl_sidno sidno) {
  DBUG_TRACE;
  tsid_lock->assert_some_wrlock();
  rpl_sidno max_sidno = get_max_sidno();
  if (sidno > max_sidno || get_hash(sidno) == nullptr) {
    for (int i = max_sidno; i < sidno; i++) {
      sidno_to_hash.push_back(
          new malloc_unordered_multimap<rpl_gno, unique_ptr_my_free<Node>>(
              key_memory_Owned_gtids_sidno_to_hash));
    }
  }
  RETURN_OK;
}

enum_return_status Owned_gtids::add_gtid_owner(const Gtid &gtid,
                                               my_thread_id owner) {
  DBUG_TRACE;
  assert(gtid.sidno <= get_max_sidno());
  assert(gtid.gno > 0);
  assert(gtid.gno < GNO_END);
  Node *n =
      (Node *)my_malloc(key_memory_tsid_map_Node, sizeof(Node), MYF(MY_WME));
  if (n == nullptr) RETURN_REPORTED_ERROR;
  n->gno = gtid.gno;
  n->owner = owner;
  /*
  printf("Owned_gtids(%p)::add sidno=%d gno=%lld n=%p n->owner=%u\n",
         this, sidno, gno, n, n?n->owner:0);
  */
  get_hash(gtid.sidno)->emplace(gtid.gno, unique_ptr_my_free<Node>(n));
  RETURN_OK;
}

void Owned_gtids::remove_gtid(const Gtid &gtid, const my_thread_id owner) {
  DBUG_TRACE;
  // printf("Owned_gtids::remove(sidno=%d gno=%lld)\n", sidno, gno);
  // assert(contains_gtid(sidno, gno)); // allow group not owned
  malloc_unordered_multimap<rpl_gno, unique_ptr_my_free<Node>> *hash =
      get_hash(gtid.sidno);
  auto it_range = hash->equal_range(gtid.gno);
  for (auto it = it_range.first; it != it_range.second; ++it) {
    if (it->second->owner == owner) {
      hash->erase(it);
      return;
    }
  }
}

bool Owned_gtids::is_intersection_nonempty(const Gtid_set *other) const {
  DBUG_TRACE;
  if (tsid_lock != nullptr) tsid_lock->assert_some_wrlock();
  Gtid_iterator git(this);
  Gtid g = git.get();
  while (g.sidno != 0) {
    if (other->contains_gtid(g.sidno, g.gno)) return true;
    git.next();
    g = git.get();
  }
  return false;
}

void Owned_gtids::get_gtids(Gtid_set &gtid_set) const {
  DBUG_TRACE;

  if (tsid_lock != nullptr) tsid_lock->assert_some_wrlock();

  Gtid_iterator git(this);
  Gtid g = git.get();
  while (g.sidno != 0) {
    gtid_set._add_gtid(g);
    git.next();
    g = git.get();
  }
}

bool Owned_gtids::contains_gtid(const Gtid &gtid) const {
  malloc_unordered_multimap<rpl_gno, unique_ptr_my_free<Node>> *hash =
      get_hash(gtid.sidno);
  tsid_lock->assert_some_lock();
  return hash->count(gtid.gno) != 0;
}

bool Owned_gtids::is_owned_by(const Gtid &gtid,
                              const my_thread_id thd_id) const {
  malloc_unordered_multimap<rpl_gno, unique_ptr_my_free<Node>> *hash =
      get_hash(gtid.sidno);
  auto it_range = hash->equal_range(gtid.gno);

  if (thd_id == 0) return it_range.first == it_range.second;

  for (auto it = it_range.first; it != it_range.second; ++it) {
    if (it->second->owner == thd_id) return true;
  }
  return false;
}