/**
 * Copyright (c) 2021 OceanBase
 * OceanBase CE is licensed under Mulan PubL v2.
 * You can use this software according to the terms and conditions of the Mulan PubL v2.
 * You may obtain a copy of Mulan PubL v2 at:
 *          http://license.coscl.org.cn/MulanPubL-2.0
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PubL v2 for more details.
 */

#define USING_LOG_PREFIX SHARE
#include "lib/mysqlclient/ob_isql_connection_pool.h"
#include "lib/mysqlclient/ob_mysql_connection.h"
#include "lib/mysqlclient/ob_isql_connection_pool.h"
#include "lib/mysqlclient/ob_mysql_proxy.h"
#include "lib/mysqlclient/ob_mysql_result.h"
#include "lib/string/ob_sql_string.h"
#include "share/ob_get_compat_mode.h"
#include "share/inner_table/ob_inner_table_schema_constants.h"
#include "share/schema/ob_schema_service_sql_impl.h"
#include "observer/ob_server_struct.h"
#include "observer/omt/ob_multi_tenant.h"

using namespace oceanbase::common;
using namespace oceanbase::sql;
using namespace oceanbase::share;
using namespace oceanbase::common::sqlclient;
using namespace oceanbase::share::schema;

ObCompatModeGetter::ObCompatModeGetter() :
  id_mode_map_(),
  sql_proxy_(NULL),
  is_inited_(false),
  is_obcdc_direct_fetching_archive_log_mode_(false)
{
}

ObCompatModeGetter::~ObCompatModeGetter()
{
  destroy();
}

ObCompatModeGetter &ObCompatModeGetter::instance()
{
  static ObCompatModeGetter the_compat_mode_getter;
  return the_compat_mode_getter;
}

int ObCompatModeGetter::get_tenant_mode(const uint64_t tenant_id, lib::Worker::CompatMode& mode)
{
  return instance().get_tenant_compat_mode(tenant_id, mode);
}

int ObCompatModeGetter::get_table_compat_mode(
    const uint64_t tenant_id,
    const int64_t table_id,
    lib::Worker::CompatMode& mode)
{
  int ret = OB_SUCCESS;
  if (OB_UNLIKELY(
      OB_INVALID_TENANT_ID == tenant_id
      || table_id <= 0)) {
    ret = OB_INVALID_ARGUMENT;
    LOG_WARN("invalid tenant_id or table_id", KR(ret), K(tenant_id), K(table_id));
  } else if (is_ls_reserved_table(table_id)) {
    ret = OB_INVALID_ARGUMENT;
    LOG_WARN("table id cannot be ls inner table id", KR(ret), K(tenant_id), K(table_id));
  } else if (is_inner_table(table_id)) {
    mode = (is_ora_virtual_table(table_id)
            || is_ora_sys_view_table(table_id)) ?
            lib::Worker::CompatMode::ORACLE :
            lib::Worker::CompatMode::MYSQL;
  } else {
    ret = instance().get_tenant_compat_mode(tenant_id, mode);
  }
  return ret;
}

int ObCompatModeGetter::get_tablet_compat_mode(
    const uint64_t tenant_id,
    const common::ObTabletID &tablet_id,
    lib::Worker::CompatMode& mode)
{
  int ret = OB_SUCCESS;
  if (OB_UNLIKELY(
      OB_INVALID_TENANT_ID == tenant_id
      || !tablet_id.is_valid())) {
    ret = OB_INVALID_ARGUMENT;
    LOG_WARN("invalid tenant_id or tablet_id", KR(ret), K(tenant_id), K(tablet_id));
  } else if (tablet_id.is_sys_tablet()) {
    mode = lib::Worker::CompatMode::MYSQL;
  } else {
    ret = instance().get_tenant_compat_mode(tenant_id, mode);
  }
  return ret;
}

int ObCompatModeGetter::check_is_oracle_mode_with_tenant_id(const uint64_t tenant_id, bool &is_oracle_mode)
{
  int ret = OB_SUCCESS;
  is_oracle_mode = false;
  lib::Worker::CompatMode compat_mode = lib::Worker::CompatMode::INVALID;

  if (OB_FAIL(instance().get_tenant_compat_mode(tenant_id, compat_mode))) {
    LOG_WARN("fail to get tenant mode", K(ret));
  } else if (lib::Worker::CompatMode::ORACLE == compat_mode) {
    is_oracle_mode = true;
  } else if (lib::Worker::CompatMode::MYSQL == compat_mode) {
    is_oracle_mode = false;
  } else {
    ret = OB_ERR_UNEXPECTED;
    LOG_WARN("compat_mode should not be INVALID.", K(ret));
  }

  return ret;
}

int ObCompatModeGetter::check_is_oracle_mode_with_table_id(
    const uint64_t tenant_id,
    const int64_t table_id,
    bool &is_oracle_mode)
{
  int ret = OB_SUCCESS;
  is_oracle_mode = false;
  lib::Worker::CompatMode compat_mode = lib::Worker::CompatMode::INVALID;
  if (OB_FAIL(instance().get_table_compat_mode(tenant_id, table_id, compat_mode))) {
    LOG_WARN("fail to get tenant mode", KR(ret), K(tenant_id), K(table_id));
  } else if (lib::Worker::CompatMode::ORACLE == compat_mode) {
    is_oracle_mode = true;
  } else if (lib::Worker::CompatMode::MYSQL == compat_mode) {
    is_oracle_mode = false;
  } else {
    ret = OB_ERR_UNEXPECTED;
    LOG_WARN("compat_mode should not be INVALID", KR(ret), K(tenant_id), K(table_id));
  }
  return ret;
}

int ObCompatModeGetter::init(common::ObMySQLProxy *proxy)
{
  int ret = OB_SUCCESS;

  ObMemAttr attr(OB_SERVER_TENANT_ID,
                 ObModIds::OB_HASH_BUCKET_TENANT_COMPAT_MODE);
  SET_USE_500(attr);
  if (IS_INIT) {
    ret = OB_INIT_TWICE;
  } else if (OB_FAIL(id_mode_map_.create(bucket_num,
                                         attr))) {
    LOG_WARN("create hash table failed", K(ret));
  } else {
    sql_proxy_ = proxy;
    is_obcdc_direct_fetching_archive_log_mode_ = false;
    is_inited_ = true;
  }

  return ret;
}

int ObCompatModeGetter::init_for_obcdc()
{
  int ret = OB_SUCCESS;

  if (IS_INIT) {
    ret = OB_INIT_TWICE;
  } else if (OB_FAIL(id_mode_map_.create(bucket_num,
        ObModIds::OB_HASH_BUCKET_TENANT_COMPAT_MODE,
        ObModIds::OB_HASH_NODE_TENANT_COMPAT_MODE))) {
    LOG_WARN("create hash table failed", K(ret));
  } else {
    is_obcdc_direct_fetching_archive_log_mode_ = true;
    is_inited_ = true;
  }

  return ret;
}

void ObCompatModeGetter::destroy()
{
  if (IS_INIT) {
    id_mode_map_.destroy();
  }
}

int ObCompatModeGetter::get_tenant_compat_mode(const uint64_t tenant_id, lib::Worker::CompatMode &mode)
{
  int ret = OB_SUCCESS;
  ObCompatibilityMode tmp_mode = ObCompatibilityMode::MYSQL_MODE;

  if (OB_UNLIKELY(OB_INVALID_ID == tenant_id)) {
    ret = OB_INVALID_ARGUMENT;
    LOG_WARN("tenant id is invalid", K(ret), K(tenant_id), K(lbt()));
  } else if (OB_SYS_TENANT_ID == tenant_id) {
    mode = lib::Worker::CompatMode::MYSQL;
  } else if (OB_GTS_TENANT_ID == tenant_id) {
    mode = lib::Worker::CompatMode::MYSQL;
  } else if (is_meta_tenant(tenant_id)) {
    mode = lib::Worker::CompatMode::MYSQL;
  } else if (OB_HASH_NOT_EXIST == (ret = id_mode_map_.get_refactored(tenant_id, mode))) {
    if (is_obcdc_direct_fetching_archive_log_mode_) {
      // do nothing, return OB_HASH_NOT_EXIST
    } else {
      bool is_exist = false;
      int overwrite = 1;

      if (! ObSchemaService::g_liboblog_mode_) {
        //先从本地tenant信息里拿
        if (OB_FAIL(GCTX.omt_->get_compat_mode(tenant_id, mode))) {
          if (ret != OB_TENANT_NOT_IN_SERVER) {
            LOG_WARN("failed to get compat mode", K(ret), K(tenant_id));
          } else {
            ret = OB_SUCCESS;
          }
        } else {
          is_exist = true;
          ret = id_mode_map_.set_refactored(tenant_id, mode, overwrite);
        }
      } else {
        ret = OB_SUCCESS;
      }

      //如果本地拿不到，再去schema里拿
      if (OB_SUCC(ret) && !is_exist) {
        if (OB_ISNULL(sql_proxy_)) {
          ret = OB_ERR_UNEXPECTED;
          LOG_WARN("sql_proxy is null", K(ret), K(lbt()));
        } else if (OB_FAIL(ObSchemaServiceSQLImpl::fetch_tenant_compat_mode(*sql_proxy_, tenant_id, tmp_mode))) {
          LOG_WARN("failed to fetch tenant compat mode", K(ret), K(tenant_id), K(lbt()));
        } else {
          if (tmp_mode == ObCompatibilityMode::MYSQL_MODE) {
            mode = lib::Worker::CompatMode::MYSQL;
            ret = id_mode_map_.set_refactored(tenant_id, mode, overwrite);
          } else if (tmp_mode == ObCompatibilityMode::ORACLE_MODE) {
            mode = lib::Worker::CompatMode::ORACLE;
            ret = id_mode_map_.set_refactored(tenant_id, mode, overwrite);
          } else {
            ret = OB_ERR_UNEXPECTED;
            LOG_WARN("unexpected compat mode", K(tmp_mode), K(ret), K(lbt()));
          }
        }
      }
    }
  }

  return ret;
}

// only for unittest
int ObCompatModeGetter::set_tenant_compat_mode(const uint64_t tenant_id, lib::Worker::CompatMode &mode)
{
  int ret = OB_SUCCESS;
  int overwrite = 1;
  if (OB_UNLIKELY(OB_INVALID_ID == tenant_id)) {
    ret = OB_INVALID_ARGUMENT;
    LOG_WARN("tenant id is invalid", K(ret), K(tenant_id));
  } else if (lib::Worker::CompatMode::MYSQL != mode &&
             lib::Worker::CompatMode::ORACLE != mode) {
    ret = OB_INVALID_ARGUMENT;
    LOG_WARN("invalid tenant compat mode", K(ret), K(tenant_id), K(mode));
  } else if (OB_FAIL(id_mode_map_.set_refactored(tenant_id, mode, overwrite))) {
    LOG_WARN("fail to set tenant compat mode", K(ret), K(tenant_id), K(mode));
  }
  return ret;
}

int ObCompatModeGetter::reset_compat_getter_map()
{
  int ret = OB_SUCCESS;
  if (!IS_INIT) {
    ret = OB_ERR_UNEXPECTED;
    LOG_WARN("compat mode geter do not init, can not reset map", K(ret));
  } else if (OB_FAIL(id_mode_map_.reuse())) {
    LOG_WARN("fail to reuse id mode map", K(ret));
  }
  return ret;
}