DB_Track/source/SQLHandler.cpp

//
//  SQLHandler.cpp
//  DB_Track
//
//  Created by Baranyai David on 2018. 10. 13..
//

#include "SQLHandler.hpp"

SQLHandler::SQLHandler()
{
    latest_value = 0;
    range = 9000000000;
    min_hits = 4; //need at least 4 hits
    server = mysql_init(server);
    try
    {
        if (!mysql_real_connect(server, "localhost", "root", "raspberry", "adatok", 0, NULL, 0))
        {
            throw "Can't connect to the server";
        }
        else
        {
            std::cout << "-----------------------------" << std::endl;
            std::cout << "Successfully connected" << std::endl;
            std::cout << "Host info: " << mysql_get_host_info(server) << std::endl;
            std::cout << "Client info: " << mysql_get_client_info() << std::endl;
            std::cout << "-----------------------------" << std::endl << std::endl;
            
            std::cout << "Getting the first value..." << std::endl;
            std::string query = "SELECT min(time_sum) FROM (SELECT *, (time_sec * (power(10, 7)) + time_ns) time_sum FROM fb55) sum";
            
            if (!mysql_query(server, query.c_str()))
            {
                MYSQL_RES *result = mysql_store_result(server);
                if (mysql_num_fields(result) == 1) //1 oszlop
                {
                    MYSQL_ROW row;
                    if(mysql_num_rows(result) == 1) //1 érték
                    {
                        row = mysql_fetch_row(result);
                        latest_value = std::stoll(row[0]);
                        std::cout << "Min value = " << latest_value <<std::endl;
                    }
                    else throw "More than one row error";
                }
                else throw "More than one column error";
            }
        }
    } catch (char const* s)
    {
        std::cout << s <<std::endl;
    }
}

SQLHandler::~SQLHandler()
{
    mysql_close(server);
    delete server;
}

//MAIN QUERY:
//SELECT * FROM (SELECT ch_id, time_sec, time_ns, (time_sec * (power(10, 7)) + time_ns) time_sum FROM fb55) s WHERE time_sum BETWEEN 2521025900 AND 2570247800 ORDER BY time_sum ASC

std::vector<Hit> SQLHandler::QueryNext()
{
    try
    {
        std::cout << "Getting next between " << latest_value << " and " << latest_value + range << std::endl;
        std::stringstream query;
        unsigned int nRow = 0;
        std::vector<Hit> hit_vector;
        while(nRow < min_hits)
        {
            hit_vector.clear();
            double max = latest_value + range;
            query << "SELECT * FROM (SELECT ch_id, peak_amp, (time_sec * (power(10, 7)) + time_ns) time_sum FROM fb55) s WHERE time_sum BETWEEN " << latest_value << " AND " << max << " ORDER BY time_sum ASC";
            
            if (!mysql_query(server, query.str().c_str())) //Start query
            {
                MYSQL_RES *result = mysql_store_result(server); //store result
                unsigned int nColumn = mysql_num_fields(result); //store column number
                if (nColumn == 3) //3 oszlop, se több, se kevesebb
                {
                    MYSQL_ROW row;
                    nRow = mysql_num_rows(result);
                    if(nRow > min_hits) //at least
                    {
                        Hit hit_helper;
                        
                        for(int i = 0; i < nRow; i++)
                        {
                            row = mysql_fetch_row(result);
                            hit_helper.channel_id = atoi(row[0]);
                            hit_helper.amplitude_peak = atoi(row[1]);
                            hit_helper.elapsed_time = std::stoll(row[2]);
                            hit_vector.push_back(hit_helper);
                        }
                        latest_value = atof(row[2]);
                        //std::cout << "Min value = " << latest_value <<std::endl;
                        return hit_vector;
                    }
                    else if(nRow != 0)
                    {
                        for(int i = 0; i < nRow; i++) //seek to the end
                        {
                            row = mysql_fetch_row(result);
                        }
                        latest_value = atoi(row[2]); //store the latest value
                    }
                }
                else throw "More than three column error";
            }
        }
        return hit_vector;
    }
    catch (char const* s)
    {
        std::cout << s << std::endl;
        return std::vector<Hit>();
    }
}

void SQLHandler::SetRange(unsigned int n_range)
{
    range = n_range;
}