/* Copyright (c) 2018, 2021, Alibaba and/or its affiliates. All rights reserved.
   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 also distributed 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/PolarDB-X Engine hereby grant you an
   additional permission to link the program and your derivative works with the
   separately licensed software that they have included with
   MySQL/PolarDB-X Engine.
   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 "bl_consensus_log.h"

#ifdef NORMANDY_CLUSTER

std::shared_ptr<BLConsensusLog> consensus_log = std::make_shared<BLConsensusLog>();
std::shared_ptr<alisql::AliSQLServer> alisql_server;
alisql::Paxos *consensus_ptr = NULL;


BLConsensusLog::BLConsensusLog()
{
  
}
BLConsensusLog::~BLConsensusLog()
{
  
}

void BLConsensusLog::init(uint64 mock_start_index_arg, ConsensusLogManager *consensus_log_manager_arg)
{
  mock_start_index = mock_start_index_arg;
  consensusLogManager_ = consensus_log_manager_arg;
}

int BLConsensusLog::getEntry(uint64_t logIndex, alisql::LogEntry &entry, bool fastFail, uint64_t serverId)
{
  my_thread_init();
  uint64 term = 0;
  std::string log_content;
  Consensus_Log_Op_Type optype = NORMAL;
  bool outerlog = FALSE;
  uint flag = 0;
  uint64 checksum = 0;
  if (logIndex < mock_start_index)
  {
    term = 0;
    log_content = "";
    optype = MOCK;
  }
  else
  { 
    if (this->consensusLogManager_->get_log_entry(serverId, logIndex, &term, log_content, &outerlog, &flag, &checksum, fastFail))
      return 1;
    if (outerlog == TRUE)
      optype = CONFIGCHANGE;
    else
    {
      if (flag & Consensus_log_event_flag::FLAG_LARGE_TRX)
        optype = LARGETRX;
      else if (flag & Consensus_log_event_flag::FLAG_LARGE_TRX_END)
        optype = LARGETRXEND;
      else
        optype = NORMAL;
    }
  }
  entry.set_term(term);
  entry.set_index(logIndex);
  entry.set_optype(optype);
  entry.set_value(log_content);
  entry.set_info(flag);
  entry.set_checksum(checksum);
  return 0;
}

int BLConsensusLog::getEntry(uint64_t logIndex, alisql::LogEntry &entry, bool fastFail)
{
  // if not set serverid, use 0 default
  return getEntry(logIndex, entry, fastFail, 0);
}


uint64_t BLConsensusLog::getLeftSize(uint64_t startLogIndex)
{
  my_thread_init();
  return consensusLogManager_->get_left_log_size(startLogIndex, 0);
}

bool BLConsensusLog::getLeftSize(uint64_t startLogIndex, uint64_t maxPacketSize)
{
    my_thread_init();
    if (consensusLogManager_->get_left_log_size(startLogIndex, maxPacketSize) > maxPacketSize)
      return TRUE;
    else
      return FALSE;
}

int BLConsensusLog::getEmptyEntry(alisql::LogEntry &entry)
{
  std::string log_content = consensusLogManager_->get_empty_log();
  entry.set_value(log_content);
  entry.set_optype(NORMAL);
  entry.set_info(0);
  entry.set_checksum(0);
  return 0;
}

uint64_t BLConsensusLog::getLastLogIndex()
{
  return (this->consensusLogManager_->get_sync_index());
}

uint64_t BLConsensusLog::getLastCachedLogIndex()
{
  return (this->consensusLogManager_->get_cache_index());
}

uint64_t BLConsensusLog::getSafeLastLogIndex()
{
  return (this->consensusLogManager_->get_final_sync_index());
}

uint64_t BLConsensusLog::appendWithCheck(const alisql::LogEntry &entry)
{
  my_thread_init();
  uint64 index = 0;
  if (entry.optype() == UNCERTAIN)
  {
    // optype UNCERTAIN means group commit replicate log send a fake log
    // do not need to write actually
    index = 0;
  }
  else
  {
    uint flag = entry.info();
    if (entry.optype() == CONFIGCHANGE)
      flag |= Consensus_log_event_flag::FLAG_CONFIG_CHANGE;
    ConsensusLogEntry log_entry = { entry.term(), entry.index(),
             entry.value().length(), (uchar*)entry.value().c_str(), entry.optype() == CONFIGCHANGE, flag, entry.checksum() };
    if (consensusLogManager_->write_log_entry(log_entry, &index, true /*check term*/))
    {
      abort();
      index = 0;
    }
  }
  return index;
}

uint64_t BLConsensusLog::append(const alisql::LogEntry &entry)
{
  my_thread_init();
  uint64 index = 0;
  if (entry.optype() == UNCERTAIN)
  {
    // optype UNCERTAIN means group commit replicate log send a fake log
    // do not need to write actually
    index = 0;
  }
  else
  {
    uint flag = entry.info();
    if (entry.optype() == CONFIGCHANGE)
      flag |= Consensus_log_event_flag::FLAG_CONFIG_CHANGE;
    ConsensusLogEntry log_entry = { entry.term(), entry.index(),
             entry.value().length(), (uchar*)entry.value().c_str(), entry.optype() == CONFIGCHANGE, flag, entry.checksum() };
    if (consensusLogManager_->write_log_entry(log_entry, &index))
    {
      abort();
      index = 0;
    }
  }
  return index;
}

uint64_t BLConsensusLog::append(const ::google::protobuf::RepeatedPtrField<alisql::LogEntry> &entries)
{
  my_thread_init();
  std::vector<ConsensusLogEntry> log_vector;
  for (auto iter = entries.begin(); iter != entries.end(); iter++)
  {
    uint flag = iter->info();
    if (iter->optype() == CONFIGCHANGE)
      flag |= Consensus_log_event_flag::FLAG_CONFIG_CHANGE;
    ConsensusLogEntry log = { iter->term(), iter->index(),
        iter->value().length(), (uchar*) iter->value().c_str(),
        iter->optype() == CONFIGCHANGE, flag, iter->checksum() };
    log_vector.push_back(log);
  }
  uint64 max_index = 0;
  
  if (consensusLogManager_->write_log_entries(log_vector, &max_index))
  {
    abort();
    max_index = 0;
  }
  DBUG_ASSERT(max_index != 0);
  return max_index;
}



void BLConsensusLog::truncateBackward(uint64_t firstIndex)
{
  my_thread_init();
  consensusLogManager_->truncate_log(firstIndex);
}


void BLConsensusLog::truncateForward(uint64_t lastIndex)
{
  my_thread_init();
  consensusLogManager_->purge_log(lastIndex);
}

int BLConsensusLog::getMetaData(const std::string &key, uint64_t *value)
{
  my_thread_init();
  if (consensusLogManager_->get_consensus_info()->consensus_init_info())
    return 1;
  if (key == "@keyVoteFor_@")
    *value = consensusLogManager_->get_consensus_info()->get_vote_for();
  else if (key == "@keyCurrentTerm_@")
    *value = consensusLogManager_->get_consensus_info()->get_current_term();
  else if (key == "@keyLastLeaderTerm_@")
    *value = consensusLogManager_->get_consensus_info()->get_last_leader_term();
  else if (key == "@keyLastLeaderLogIndex_@")
    *value = consensusLogManager_->get_consensus_info()->get_start_apply_index();
  else if (key == "@keyScanIndex_@")
    *value = consensusLogManager_->get_consensus_info()->get_cluster_recover_index();
  else if (key == "@keyClusterId_@")
    *value = consensusLogManager_->get_consensus_info()->get_cluster_id();
  else
    DBUG_ASSERT(0);
  return 0;
}

int BLConsensusLog::getMetaData(const std::string &key, std::string &value)
{
  my_thread_init();
  if (consensusLogManager_->get_consensus_info()->consensus_init_info())
    return 1;
  if (key == "@keyMemberConfigure_@")
    value = consensusLogManager_->get_consensus_info()->get_cluster_info();
  else if (key == "@keyLearnerConfigure_@")
    value = consensusLogManager_->get_consensus_info()->get_cluster_learner_info();
  else
    DBUG_ASSERT(0);
  return 0;
}


int BLConsensusLog::setMetaData(const std::string &key, const uint64_t value)
{
  my_thread_init();
  if (key == "@keyVoteFor_@")
    consensusLogManager_->get_consensus_info()->set_vote_for(value);
  else if (key == "@keyCurrentTerm_@")
    consensusLogManager_->get_consensus_info()->set_current_term(value);
  else if (key == "@keyLastLeaderTerm_@")
    consensusLogManager_->set_start_apply_term_if_need(value);
  else if (key == "@keyLastLeaderLogIndex_@")
    consensusLogManager_->set_start_apply_index_if_need(value);
  else if (key == "@keyScanIndex_@")
    consensusLogManager_->get_consensus_info()->set_cluster_recover_index(value);
  else if (key == "@keyClusterId_@")
    consensusLogManager_->get_consensus_info()->set_cluster_id(value);
  else
    DBUG_ASSERT(0);
  
  if (consensusLogManager_->get_consensus_info()->flush_info(true, true))
  {
    abort();
    return 1;
  }
  return 0;
}

int BLConsensusLog::setMetaData(const std::string &key, const std::string &value)
{
  my_thread_init();
  if (key == "@keyMemberConfigure_@")
    consensusLogManager_->get_consensus_info()->set_cluster_info(value);
  else if (key == "@keyLearnerConfigure_@")
    consensusLogManager_->get_consensus_info()->set_cluster_learner_info(value);
  else
    DBUG_ASSERT(0);

  if (consensusLogManager_->get_consensus_info()->flush_info(true, true))
  {
    abort();
    return 1;
  }
  return 0;
}

void BLConsensusLog::setTerm(uint64_t term)
{
  mysql_mutex_lock(consensusLogManager_->get_term_lock());
  this->currentTerm_ = term;
  mysql_mutex_unlock(consensusLogManager_->get_term_lock());
}

uint64_t BLConsensusLog::getLength()
{
  return consensusLogManager_->get_exist_log_length();
}

void BLConsensusLog::packLogEntry(uchar* buffer, size_t buf_size, uint64 term, uint64 index, Consensus_Log_Op_Type entry_type, alisql::LogEntry& log_entry)
{
  std::string log_content((char*)buffer, buf_size);
  log_entry.set_value(log_content);
  log_entry.set_term(term);
  log_entry.set_index(index);
  log_entry.set_optype(entry_type);
}

bool BLConsensusLog::isStateMachineHealthy()
{
  return consensusLogManager_->is_state_machine_ready();
}

#endif