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++ // Copyright (C) 2020 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++
++ #ifndef INITDB_H
++ #define INITDB_H
++
++ #include <QDate>
++ #include <QSqlError>
++ #include <QSqlQuery>
++
++ void addBook(QSqlQuery &q, const QString &title, int year, const QVariant &authorId,
++ const QVariant &genreId, int rating)
++ {
++ q.addBindValue(title);
++ q.addBindValue(year);
++ q.addBindValue(authorId);
++ q.addBindValue(genreId);
++ q.addBindValue(rating);
++ q.exec();
++ }
++
++ QVariant addGenre(QSqlQuery &q, const QString &name)
++ {
++ q.addBindValue(name);
++ q.exec();
++ return q.lastInsertId();
++ }
++
++ QVariant addAuthor(QSqlQuery &q, const QString &name, QDate birthdate)
++ {
++ q.addBindValue(name);
++ q.addBindValue(birthdate);
++ q.exec();
++ return q.lastInsertId();
++ }
++
++ const auto BOOKS_SQL = QLatin1String(R"(
++ create table books(id integer primary key, title varchar, author integer,
++ genre integer, year integer, rating integer)
++ )");
++
++ const auto AUTHORS_SQL = QLatin1String(R"(
++ create table authors(id integer primary key, name varchar, birthdate date)
++ )");
++
++ const auto GENRES_SQL = QLatin1String(R"(
++ create table genres(id integer primary key, name varchar)
++ )");
++
++ const auto INSERT_AUTHOR_SQL = QLatin1String(R"(
++ insert into authors(name, birthdate) values(?, ?)
++ )");
++
++ const auto INSERT_BOOK_SQL = QLatin1String(R"(
++ insert into books(title, year, author, genre, rating)
++ values(?, ?, ?, ?, ?)
++ )");
++
++ const auto INSERT_GENRE_SQL = QLatin1String(R"(
++ insert into genres(name) values(?)
++ )");
++
++ QSqlError initDb()
++ {
++ QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
++ db.setDatabaseName(":memory:");
++
++ if (!db.open())
++ return db.lastError();
++
++ QStringList tables = db.tables();
++ if (tables.contains("books", Qt::CaseInsensitive)
++ && tables.contains("authors", Qt::CaseInsensitive))
++ return QSqlError();
++
++ QSqlQuery q;
++ if (!q.exec(BOOKS_SQL))
++ return q.lastError();
++ if (!q.exec(AUTHORS_SQL))
++ return q.lastError();
++ if (!q.exec(GENRES_SQL))
++ return q.lastError();
++
++ if (!q.prepare(INSERT_AUTHOR_SQL))
++ return q.lastError();
++ QVariant asimovId = addAuthor(q, QLatin1String("Isaac Asimov"), QDate(1920, 2, 1));
++ QVariant greeneId = addAuthor(q, QLatin1String("Graham Greene"), QDate(1904, 10, 2));
++ QVariant pratchettId = addAuthor(q, QLatin1String("Terry Pratchett"), QDate(1948, 4, 28));
++
++ if (!q.prepare(INSERT_GENRE_SQL))
++ return q.lastError();
++ QVariant sfiction = addGenre(q, QLatin1String("Science Fiction"));
++ QVariant fiction = addGenre(q, QLatin1String("Fiction"));
++ QVariant fantasy = addGenre(q, QLatin1String("Fantasy"));
++
++ if (!q.prepare(INSERT_BOOK_SQL))
++ return q.lastError();
++ addBook(q, QLatin1String("Foundation"), 1951, asimovId, sfiction, 3);
++ addBook(q, QLatin1String("Foundation and Empire"), 1952, asimovId, sfiction, 4);
++ addBook(q, QLatin1String("Second Foundation"), 1953, asimovId, sfiction, 3);
++ addBook(q, QLatin1String("Foundation's Edge"), 1982, asimovId, sfiction, 3);
++ addBook(q, QLatin1String("Foundation and Earth"), 1986, asimovId, sfiction, 4);
++ addBook(q, QLatin1String("Prelude to Foundation"), 1988, asimovId, sfiction, 3);
++ addBook(q, QLatin1String("Forward the Foundation"), 1993, asimovId, sfiction, 3);
++ addBook(q, QLatin1String("The Power and the Glory"), 1940, greeneId, fiction, 4);
++ addBook(q, QLatin1String("The Third Man"), 1950, greeneId, fiction, 5);
++ addBook(q, QLatin1String("Our Man in Havana"), 1958, greeneId, fiction, 4);
++ addBook(q, QLatin1String("Guards! Guards!"), 1989, pratchettId, fantasy, 3);
++ addBook(q, QLatin1String("Night Watch"), 2002, pratchettId, fantasy, 3);
++ addBook(q, QLatin1String("Going Postal"), 2004, pratchettId, fantasy, 3);
++
++ return QSqlError();
++ }
++
++ #endif