#include "MySQLWrapper.h"
#include "MySQLInclude.h"
#include <string>
using namespace std;

/**********************
MySQL Result Class.
**********************/

struct MySQLResult::impl
{
    MYSQL_RES* res;
};

MySQLResult::MySQLResult() : pimpl(new impl)
{
    pimpl->res=nullptr;
}

MySQLResult::~MySQLResult()
{
    if(pimpl->res)
    {
        mysql_free_result(pimpl->res);
        pimpl->res=nullptr;
    }
    delete pimpl;
}

unsigned int MySQLResult::getNumFields()
{
    return mysql_num_fields(pimpl->res);
}

uint64_t MySQLResult::getNumRows()
{
    return mysql_num_rows(pimpl->res);
}

char* MySQLResult::getFieldName(int Index)
{
    return mysql_fetch_fields(pimpl->res)[Index].name;
}

void MySQLResult::stepRow(const std::function<void(char** RowPtr, unsigned long* FieldLength)>& func)
{
    MYSQL_ROW row;
    while((row=mysql_fetch_row(pimpl->res)))
    {
        if(func)
        {
            func(row,mysql_fetch_lengths(pimpl->res));
        }
    }
}


/**********************
MySQL Connection Class.
**********************/

struct MySQLConn::impl
{
    MYSQL m;
    string lasterr;
    unsigned int lasterrcode;
};

MySQLConn::MySQLConn() : pimpl(new impl)
{
    mysql_init(&(pimpl->m));
    pimpl->lasterrcode=0;
}

MySQLConn::~MySQLConn()
{
    mysql_close(&(pimpl->m));
}

int MySQLConn::connect(const std::string& host, const std::string& user, const std::string& passwd, const std::string& db, unsigned int port)
{
    if(mysql_real_connect(&(pimpl->m),host.c_str(),user.c_str(),passwd.c_str(),db.c_str(),port,nullptr,0)==nullptr)
    {
        _doUpdateError();
        return -1;
    }
    else
    {
        return 0;
    }
}

FILE* fp=[](){FILE* s=fopen("sql_log.txt","a");fprintf(s,"%p=============\n",s);return s;}();

int MySQLConn::exec(const std::string& SQLCommand, const std::function<void(MySQLResult&)>& func)
{
    fprintf(fp,"%p: %s\n",this,SQLCommand.c_str());
    fflush(fp);

    if(mysql_real_query(&(pimpl->m),SQLCommand.c_str(),SQLCommand.size())!=0)
    {
        /// Failed to Query
        _doUpdateError();
        return -1;
    }

    MYSQL_RES* pres=mysql_store_result(&(pimpl->m));
    if(pres==nullptr)
    {
        /// Store Result Returns Null.
        if(getFieldCount()==0)
        {
            /// No Error.
            return 1;
        }
        else
        {
            /// Failed to store result.
            _doUpdateError();
            return -2;
        }
    }

    MySQLResult res;
    res.pimpl->res=pres;

    if(func) func(res);

    /// MySQL_RES will be released normally by MySQLResult::~MySQLResult()
    return 0;
}

unsigned int MySQLConn::getFieldCount()
{
    return mysql_field_count(&(pimpl->m));
}

uint64_t MySQLConn::getAffectedRows()
{
    return mysql_affected_rows(&(pimpl->m));
}

const std::string& MySQLConn::getError()
{
    return pimpl->lasterr;
}

unsigned int MySQLConn::getErrCode()
{
    return pimpl->lasterrcode;
}

///protected
void MySQLConn::_doUpdateError()
{
    pimpl->lasterr=mysql_error(&(pimpl->m));
    pimpl->lasterrcode=mysql_errno(&(pimpl->m));
}