appdatabase.cpp

#include "appdatabase.h"

void AppDatabase::createIfNotExist()
{
    QSqlQuery query;
    if (!query.exec("CREATE TABLE IF NOT EXISTS messages ( \
                    id				INTEGER NOT NULL, \
                    senderName		TEXT, \
                    text			TEXT, \
                    time			INTEGER, \
                    channelNumber	INTEGER, \
                    PRIMARY KEY(id AUTOINCREMENT) \
                    );")) {
        qDebug() << query.lastError().text();
        throw std::runtime_error("Can't create table \"messages\": "+query.lastError().text().toStdString());
    }
//    if (!query.exec("CREATE TABLE \"pairs\" ( \
//                    \"key\"	TEXT NOT NULL UNIQUE, \
//                    \"value\"	TEXT \
//                    );")) {
//        qDebug() << query.lastError().text();
//        throw std::runtime_error("Can't create table \"pairs\": "+query.lastError().text().toStdString());
//    }

//        insertIfNotExist("pairs", {"key", "name"}, {{"value", QHostInfo::localHostName().first(8)}});
}

void AppDatabase::insertIfNotExist(QString table, QPair<QString, QVariant> key, QMap<QString, QVariant> columnValues)
{
    QString columnNames = columnValues.keys().join(',');
    QString columnVars = ':'+columnValues.keys().join(",:");
    QSqlQuery query;
    query.prepare("IF NOT EXISTS (SELECT * FROM pairs \
                  WHERE "+key.first+" = :key) \
                  BEGIN \
                      INSERT INTO pairs ("+columnNames+") \
                      VALUES ("+columnVars+") \
                  END");
    query.bindValue(":key", key.second);
    for (auto key : columnValues.keys()) {
        query.bindValue(':'+key, columnValues[key]);
    }
    if (!query.exec()) {
        qDebug() << query.lastError().text();
        throw std::runtime_error("Can't insert into table \"\": "+query.lastError().text().toStdString());
    }
    db.commit();
}

AppDatabase::AppDatabase(QObject *parent)
    : QObject{parent}
    , db(QSqlDatabase::addDatabase("QSQLITE"))
{
    QString path = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
    if (!QDir().mkpath(path))
    {
        qDebug() << "Can't create application files directory";
        QCoreApplication::quit();
    }
    qDebug() << path;

    db.setDatabaseName(path+"/application_db.db");

    if (!db.open()) {
        qDebug() << db.lastError().text();
        throw std::runtime_error("Can't open SQLite database: "+db.lastError().text().toStdString());
    }

    createIfNotExist();
}