/*
 * This file is a part of Winix
 * and is not publicly distributed
 * 
 * Copyright (c) 2010-2013, Tomasz Sowa
 * All rights reserved.
 * 
 */

#include <unistd.h>
#include "dbconn.h"
#include "core/log.h"
#include "core/error.h"





DbConn::DbConn()
{
	pg_conn      = 0;
}



DbConn::~DbConn()
{
	Close();
}



PGconn * DbConn::GetPgConn()
{
	return pg_conn;
}



void DbConn::SetConnParam(const std::string & d, const std::string & u, const std::string & p)
{
	db_database = d;
	db_user     = u;
	db_pass     = p;
}



void DbConn::Connect()
{
	Close();
	
	conn_info.Clear();
	conn_info.SetExtented(false);

	conn_info << R("dbname=")    << db_database 
			  << R(" user=")     << db_user
			  << R(" password=") << db_pass;

	pg_conn = PQconnectdb(conn_info.CStr());
	
	// warning! pg_conn can be not null but there cannnot be a connection established
	// use PQstatus(pg_conn) to check whether the connection works fine
}



void DbConn::LogConnectionSocket()
{
	log << log2 << "Db: connection to the database works fine" << logend;
	log << log3 << "Db: connection socket: " << PQsocket(pg_conn) << logend;
}



void DbConn::WaitForConnection()
{
	if( !pg_conn || PQstatus(pg_conn) != CONNECTION_OK )
	{
		log << log3 << "Db: waiting for the db to be ready...." << logend << logsave;

		while( !AssertConnection(false, false) )
			sleep(5);

		LogConnectionSocket();
	}
}



void DbConn::Close()
{
	if( pg_conn )
	{
		PQfinish(pg_conn);
		pg_conn = 0;
	}
}



bool DbConn::AssertConnection(bool put_log, bool throw_if_no_connection)
{
bool was_connection = true;


	if( !pg_conn )
	{
		was_connection = false;
		Connect();
	}
	else
	if( PQstatus(pg_conn) != CONNECTION_OK )
	{
		if( put_log )
			log << log2 << "Db: connection to the database is lost, trying to recover" << logend;

		was_connection = false;
		PQreset(pg_conn);
	}
	
	
	if( pg_conn && PQstatus(pg_conn) == CONNECTION_OK )
	{
		if( !was_connection )
		{
			if( put_log )
				LogConnectionSocket();

			SetDbParameters();
		}

		return true;
	}
	else
	{
		if( put_log )
			log << log1 << "Db: connection to db server cannot be established" << logend;

		if( throw_if_no_connection )
			throw Error(WINIX_ERR_DB_FATAL_ERROR_DURING_CONNECTING);

		return false;
	}
}



void DbConn::SetDbParameters()
{
	if( PQsetClientEncoding(pg_conn, "UTF8") == -1 )
		log << log1 << "Db: Can't set the proper client encoding" << logend;
}