#include "DbManager.h"
#include <MySqlConnector.h>
#include <string>
#include <fstream>
#include <streambuf>
#include <sstream>

DbManager::DbManager( const std::string& host, const std::string& database, const std::string& user, const std::string& pw, uint16_t port ) :
  m_host( host ),
  m_database( database ),
  m_user( user ),
  m_password( pw ),
  m_port( port )	
{
}

DbManager::~DbManager()
{

}

bool DbManager::execute( const std::string& sql )
{
  try
  {
    auto stmt = m_pConnection->createStatement();
    bool result = stmt->execute( sql );
    return result;
  }
  catch( std::runtime_error& e )
  {
    m_lastError = e.what();
    return false;
  }
}

bool DbManager::connect()
{
  std::shared_ptr< Mysql::MySqlBase > base( new Mysql::MySqlBase() );
  Mysql::optionMap options;
  options[ Mysql::MYSQL_OPT_RECONNECT ] = "1";
  options[ Mysql::MYSQL_SET_CHARSET_NAME ] = "utf8";

  try
  {
    m_pConnection = base->connect( m_host, m_user, m_password, options, m_port );
  }
  catch( std::runtime_error& e )
  {
    m_lastError = e.what();
    return false;
  }
  return true;
}

bool DbManager::selectSchema()
{
  if( !m_pConnection )
  {
    m_lastError = "No valid db connection!";	  
    return false;
  }

  try
  {
    m_pConnection->setSchema( m_database );
  }
  catch( std::runtime_error& e )
  {
    m_lastError = e.what();
    return false;
  }
  return true;
}

const std::string& DbManager::getLastError()
{
  return m_lastError;
}

void DbManager::setMode( Mode mode )
{
  m_mode = mode;
}

Mode DbManager::getMode() const
{
  return m_mode;
}

bool DbManager::performAction()
{
  bool result = false;
  execute( " SET autocommit = 0 " );
  m_pConnection->beginTransaction();

  switch( m_mode )
  {
    case Mode::INIT:
      result = modeInit();
      break;
    case Mode::LIQUIDATE:
      break;
    case Mode::UPDATE:
      break;
    case Mode::CHECK:
      break;
    case Mode::CLEAN_CHARS:
      break;
  }
  if( !result )
    m_pConnection->rollbackTransaction();
  else
    m_pConnection->commitTransaction();

  return result;
}

bool DbManager::modeInit()
{

  const std::string schemaFile = "sql/schema/schema.sql";
  const std::string insertFile = "sql/schema/inserts.sql";

  bool result = false;
  bool dbCreated = false;

  if( selectSchema() )
  {
    std::string query = "SELECT COUNT(*) "
                        "FROM information_schema.tables "
                        "WHERE table_type = 'BASE TABLE' "
                        "AND table_schema = '" + m_database + "';";
    dbCreated = true;
    try
    {
      auto stmt = m_pConnection->createStatement();
      auto resultSet = stmt->executeQuery( query );

      if( !resultSet->next() )
        return false;

      auto count = resultSet->getUInt( 1 );
      if( count )
      {
        m_lastError = "Database " + m_database + " still contains tables. <Liquidate> it first!";
        return false;
      }

    }
    catch( std::runtime_error& e )
    {
      m_lastError = e.what();
      return false;
    }
  }

  if( !dbCreated )
    if( !execute( "CREATE DATABASE " + m_database ) )
      return false;

  if( !selectSchema() )
  {
    m_lastError = "Database not created.";
    return false;
  }

  std::ifstream t( schemaFile );
  if( !t.is_open() )
  {
    m_lastError = "File " + schemaFile + " does not exist!";
    return false;
  }
  std::string content( ( std::istreambuf_iterator< char >( t ) ),
                       ( std::istreambuf_iterator< char >( )    ) );
  std::string delimiter = ";";

  size_t pos = 0;
  std::string token;
  while( ( pos = content.find( delimiter ) ) != std::string::npos )
  {
    token = content.substr( 1, pos );
    size_t pos1 = token.find_first_not_of( "\r\n" );
    token = token.substr( pos1, token.size() );
    size_t pos2 = token.find_first_of( "\r\n" );
    std::cout << token.substr( 0, pos2 - 1 ) << std::endl;

    if( !execute( token ) )
      return false;

    content.erase(0, pos + delimiter.length());
  }

  // we do not actually want this to stay atm...
  if( !execute( "DROP DATABASE " + m_database ) )
    return false;

  return true;
}