/**
 * db_bridge/postgresql_db.cpp
 * Copyright 2008 (C) Markus Broeker
 */

#include <postgresql_db.h>

PostgreSQL_DB::PostgreSQL_DB (std::string srv, std::string usr, std::string pwd, std::string db)
{
    server = (srv != "") ? "host=" + srv : "";
    user = (usr != "") ? "user=" + usr : "user=" + std::string (getenv ("USER"));
    password = (pwd != "") ? "password=" + pwd : "";
    database = "dbname=" + db;

    if (server != "" && pwd == "") {
        std::cerr << "HBA funktioniert nur mit Passwoertern..." << std::endl;
    }

    conninfo = server + " " + user + " " + password + " " + database;
}

PostgreSQL_DB::~PostgreSQL_DB ()
{
    if (conn != NULL) {
        PQfinish (conn);
        std::cerr << "Datenbank wird geschlossen" << std::endl;
    }
}

bool PostgreSQL_DB::connect ()
{
    if ((conn = PQconnectdb (conninfo.c_str ())) == NULL) {
        std::cerr << server << ": " << "ERROR " << std::endl;
        return false;
    }

    std::cerr << "Verbindungsparameter: " << conninfo << std::endl;
    return true;
}

std::vector < std::vector<std::string> >PostgreSQL_DB::query (std::string sql_string)
{
    std::vector <std::string> vec;
    std::vector < std::vector <std::string> >rows;
    PGresult *res;
    int i, j, nFields;

    /*
     * send SQL query
     */
    res = PQexec (conn, sql_string.c_str ());

    nFields = PQnfields (res);

    std::cout << "Die Abfrage ergab " << nFields << " Zeilen." << std::endl;

    /*
     * push everything into a vector< vector<string> >
     */
    for (i = 0; i < PQntuples (res); i++) {
        for (j = 0; j < nFields; j++) {
            vec.push_back (PQgetvalue (res, i, j));
        }
        rows.push_back (vec);
        vec.clear ();
    }

    if (res != NULL) {
        PQclear (res);
    }

    return rows;
}