#include <exception>
#include <unordered_map>
#include "Parameters.h"
#include "sqlite/sqlite3.h"

using namespace std;

Parameters::Parameters(void)
{
}

Parameters::Parameters(const string & strFilePath)
{
	sqlite3 * pdbParameter;
	string path;

	int returnCode;
	int nRowCount;
	int nColCount;

	char ** result;
	char * pszMessage;
	char szSQL[] = 
		"select name, value from sys_parameters ";

	returnCode = sqlite3_open( strFilePath.c_str(), &pdbParameter );

	if ( returnCode != SQLITE_OK )
	{
		const char * pszMessage = sqlite3_errmsg(pdbParameter);
		throw runtime_error( pszMessage );
	}

	//查询
	returnCode = sqlite3_get_table( pdbParameter, szSQL, &result, &nRowCount, &nColCount, &pszMessage );

	if ( returnCode != SQLITE_OK )
	{
		const char * pszMessage = sqlite3_errmsg(pdbParameter);
		throw runtime_error(pszMessage);
	}

	for ( int nRowIndex = nColCount; nRowIndex < nColCount*(nRowCount+1); nRowIndex += nColCount )
	{
		string strName = result[nRowIndex];
		string strValue = result[nRowIndex+1];

		m_parameters[strName] = strValue;
	}

	//清理
	sqlite3_free_table( result );
	sqlite3_close( pdbParameter );

	//保存文件路径
	m_strDbFilePath = strFilePath;
}


Parameters::~Parameters(void)
{
}

string Parameters::getParameter(const string & strParaName)
{
	return m_parameters[strParaName];
}

void Parameters::setParameter(const string & strParaName, const string & strParaValue)
{
	if ( m_parameters.find( strParaName) == m_parameters.end() )
	{
		throw runtime_error( "参数名称错误！" );
	}

	m_parameters[strParaName] = strParaValue;

	sqlite3 * pDb = NULL;
	int iReturnCode;
	char * szMsg;
	string strSQL = 
		"update sys_parameters set value = '";

	strSQL.append( strParaValue );
	strSQL.append( "' where name = '" );
	strSQL.append( strParaName );
	strSQL.append( "' " );

	iReturnCode = sqlite3_open( m_strDbFilePath.c_str(), &pDb );

	if ( iReturnCode != SQLITE_OK )
	{
		throw runtime_error( sqlite3_errmsg( pDb ));
	}

	iReturnCode = sqlite3_exec( pDb, strSQL.c_str(), NULL, NULL, &szMsg );

	if ( iReturnCode != SQLITE_OK )
	{
		throw runtime_error( szMsg );
	}

	sqlite3_close( pDb );
}