/**
 * 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.
 */

#include "ob_query_response_time.h"
#include "observer/omt/ob_tenant_timezone_mgr.h"
#include "observer/omt/ob_tenant_config_mgr.h"

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

namespace oceanbase {
namespace observer {

ObRSTUtility::ObRSTUtility():base_(0)
{
    max_dec_value_ = MILLION;
    for(int i= 0; OB_QRT_POSITIVE_LENGTH > i; ++i)
        max_dec_value_ *= 10;
    setup(OB_QRT_DEFAULT_BASE);
}

ObRSTUtility::~ObRSTUtility()
{}

int ObRSTUtility::setup(uint base)
{
    int ret = OB_SUCCESS;
    if (base < 2) {
        ret = OB_INVALID_ARGUMENT;
    } else if(base != base_) {
        base_= base;
        
        uint64_t value = MILLION;
        negative_count_= 0;
        while(value > 0){
            negative_count_ += 1;
            value /= base_;
        }
        negative_count_ -= 1;

        value = MILLION;
        positive_count_ = 0;
        while(value < max_dec_value_){
            positive_count_ += 1;
            value *= base_;
        }
        bound_count_ = negative_count_ + positive_count_;

        value = MILLION;
        for(uint i = 0; i < negative_count_; ++i) {
            value /= base_;
            bound_[negative_count_ - i - 1] = value;
        }

        value = MILLION;
        for(uint i = 0; i < positive_count_; ++i) {
            bound_[negative_count_ + i] = value;
            value *= base_;
        }
    }
    return 0;
}

ObRSTTimeCollector::ObRSTTimeCollector():mutex_()
{
    flush();
}
ObRSTTimeCollector::~ObRSTTimeCollector()
{}

int ObRSTTimeCollector::flush()
{
    for(int i = 0; i < OB_QRT_OVERALL_COUNT + 1; i++) {
        count_[i] = 0;
        total_[i] = 0;
    }
    return 0;
}

int ObRSTTimeCollector::collect(uint64_t time)
{
    int i = 0;
    for(int count = utility_.bound_count(); count > i; ++i) {
        if(utility_.bound(i) > time) {
            count_[i]++;
            total_[i] += time;
            break;
        }
    }
    return 0;
}

ObRSTCollector::ObRSTCollector():inited_(false)
{}

ObRSTCollector::~ObRSTCollector(){
    inited_ = false;
    collector_map_.clear();
}

ObRSTCollector& ObRSTCollector::get_instance(){
    static ObRSTCollector collector_instance_;
    if (!collector_instance_.inited_){
        collector_instance_.init();
    }
    return collector_instance_;
}

int ObRSTCollector::init()
{
  int ret = OB_SUCCESS;
  if (inited_){
    ret = OB_INIT_TWICE;
  } else if (!collector_map_.created() &&
        OB_FAIL(collector_map_.create(
            common::OB_MAX_SERVER_TENANT_CNT, ObModIds::OB_HASH_BUCKET, ObModIds::OB_HASH_NODE))) {
      ret = OB_NOT_INIT;
      SQL_ENG_LOG(WARN, "create time collector map failed", K(ret));
    } else {
        inited_ = true;
    } 
  return ret;
}

int ObRSTCollector::collect_query_response_time(uint64_t tenant_id, uint64_t time){
    int ret = OB_SUCCESS;
    omt::ObTenantConfigGuard tenant_config(TENANT_CONF(tenant_id));
    if(tenant_config->query_response_time_stats){
        ObRSTTimeCollector* time_collector;
        if (OB_FAIL(ret = collector_map_.get_refactored(tenant_id, time_collector))){
          SERVER_LOG(WARN, "time collector of the tenant does not exist", K(tenant_id), K(time), K(ret));
        } else {
            lib::ObMutexGuard guard(time_collector->mutex_);
            if(OB_FAIL(ret = time_collector->collect(time))){
                SERVER_LOG(WARN, "time collector of the tenant collect time failed", K(tenant_id), K(time), K(ret));
            }
        }
    }
    return ret;
}

int ObRSTCollector::flush_query_response_time(uint64_t tenant_id,const ObString& is_enable) {
    int ret = OB_SUCCESS;
    bool is_enable_value = false;
    bool is_valid = false;
    is_enable_value = ObConfigBoolParser::get(is_enable.ptr(), is_valid);
    omt::ObTenantConfigGuard tenant_config(TENANT_CONF(tenant_id));
    if (!is_valid) {
        ret = OB_INVALID_ARGUMENT;
        SERVER_LOG(WARN, "invalid bool str", K(ret), K(is_enable), K(tenant_id));
    } else if (is_enable_value) {
        ObRSTTimeCollector* time_collector;
        if (OB_FAIL(ret = collector_map_.get_refactored(tenant_id, time_collector))){
            SERVER_LOG(WARN, "time collector of the tenant does not exist", K(ret), K(tenant_id));
        } else {
            lib::ObMutexGuard guard(time_collector->mutex_);
            if (OB_FAIL(ret = time_collector->setup(tenant_config->query_response_time_range_base))){
                SERVER_LOG(WARN, "time collector of the tenant set range base failed", K(ret), K(tenant_id));
            } else if (OB_FAIL(ret = time_collector->flush())){
                SERVER_LOG(WARN, "time collector of the tenant flush failed", K(ret), K(tenant_id));
            } 
        }    
    }
    return ret;
}

int ObRSTCollector::enable_query_response_time(uint64_t tenant_id){
    int ret = OB_SUCCESS;
    omt::ObTenantConfigGuard tenant_config(TENANT_CONF(tenant_id));
    if(tenant_config->query_response_time_stats){
        SERVER_LOG(INFO, "query_response_time_stats already turn on", K(ret), K(tenant_id));
    } else if (OB_FAIL(ret = collector_map_.set_refactored(tenant_id, new ObRSTTimeCollector()))) {
        if (OB_HASH_EXIST == ret) {
            ret = OB_ERR_ALREADY_EXISTS;
        }
    }
    return ret;
}

int ObRSTCollector::free_query_response_time(uint64_t tenant_id){
    int ret = OB_SUCCESS;
    omt::ObTenantConfigGuard tenant_config(TENANT_CONF(tenant_id));
    if(!tenant_config->query_response_time_stats){
        SERVER_LOG(INFO, "query_response_time_stats already turn off", K(ret), K(tenant_id));
    } else if (OB_FAIL(collector_map_.erase_refactored(tenant_id))) {
        SERVER_LOG(WARN,"erase the time collector failed", K(tenant_id));
    }
    return ret;
}

int ObRSTCollector::control_query_response_time(uint64_t tenant_id, const ObString& is_enable){
    int ret = OB_SUCCESS;
    bool is_enable_value = false;
    bool is_valid = false;
    is_enable_value = ObConfigBoolParser::get(is_enable.ptr(), is_valid);
    if (is_enable_value) {
        if (OB_FAIL(ret = enable_query_response_time(tenant_id))){
            SERVER_LOG(WARN, "enable the query response time failed", K(ret),K(tenant_id));
        }
    } else if (OB_FAIL(ret = free_query_response_time(tenant_id))){
        SERVER_LOG(WARN, "free the query response time failed", K(ret),K(tenant_id));
    }
    return ret;
}

}  // namespace observer
}  // namespace oceanbase