/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
*
#include "bookwindow.h"
#include "bookdelegate.h"
#include "initdb.h"

#include <QtSql>

BookWindow::BookWindow()
{
ui.setupUi(this);

if (!QSqlDatabase::drivers().contains("QSQLITE"))
QMessageBox::critical(
this,
"Unable to load database",
"This demo needs the SQLITE driver"
);

// Initialize the database:
QSqlError err = initDb();
if (err.type() != QSqlError::NoError) {
showError(err);
return;
}

// Create the data model:
model = new QSqlRelationalTableModel(ui.bookTable);
model->setEditStrategy(QSqlTableModel::OnManualSubmit);
model->setTable("books");

// Remember the indexes of the columns:
authorIdx = model->fieldIndex("author");
genreIdx = model->fieldIndex("genre");

// Set the relations to the other database tables:
model->setRelation(authorIdx, QSqlRelation("authors", "id", "name"));
model->setRelation(genreIdx, QSqlRelation("genres", "id", "name"));

// Set the localized header captions:
model->setHeaderData(authorIdx, Qt::Horizontal, tr("Author Name"));
model->setHeaderData(genreIdx, Qt::Horizontal, tr("Genre"));
model->setHeaderData(model->fieldIndex("title"),
Qt::Horizontal, tr("Title"));
model->setHeaderData(model->fieldIndex("year"), Qt::Horizontal, tr("Year"));
model->setHeaderData(model->fieldIndex("rating"),
Qt::Horizontal, tr("Rating"));

// Populate the model:
if (!model->select()) {
showError(model->lastError());
return;
}

// Set the model and hide the ID column:
ui.bookTable->setModel(model);
ui.bookTable->setItemDelegate(new BookDelegate(ui.bookTable));
ui.bookTable->setColumnHidden(model->fieldIndex("id"), true);
ui.bookTable->setSelectionMode(QAbstractItemView::SingleSelection);

// Initialize the Author combo box:
ui.authorEdit->setModel(model->relationModel(authorIdx));
ui.authorEdit->setModelColumn(
model->relationModel(authorIdx)->fieldIndex("name"));

ui.genreEdit->setModel(model->relationModel(genreIdx));
ui.genreEdit->setModelColumn(
model->relationModel(genreIdx)->fieldIndex("name"));

// Lock and prohibit resizing of the width of the rating column:
ui.bookTable->horizontalHeader()->setSectionResizeMode(
model->fieldIndex("rating"),
QHeaderView::ResizeToContents);

QDataWidgetMapper *mapper = new QDataWidgetMapper(this);
mapper->setModel(model);
mapper->setItemDelegate(new BookDelegate(this));
mapper->addMapping(ui.titleEdit, model->fieldIndex("title"));
mapper->addMapping(ui.yearEdit, model->fieldIndex("year"));
mapper->addMapping(ui.authorEdit, authorIdx);
mapper->addMapping(ui.genreEdit, genreIdx);
mapper->addMapping(ui.ratingEdit, model->fieldIndex("rating"));

connect(ui.bookTable->selectionModel(),
&QItemSelectionModel::currentRowChanged,
mapper,
&QDataWidgetMapper::setCurrentModelIndex
);

ui.bookTable->setCurrentIndex(model->index(0, 0));
createMenuBar();
}

void BookWindow::showError(const QSqlError &err)
{
QMessageBox::critical(this, "Unable to initialize Database",
"Error initializing database: " + err.text());
}

void BookWindow::createMenuBar()
{
QAction *quitAction = new QAction(tr("&Quit"), this);
QAction *aboutAction = new QAction(tr("&About"), this);
QAction *aboutQtAction = new QAction(tr("&About Qt"), this);

QMenu *fileMenu = menuBar()->addMenu(tr("&File"));
fileMenu->addAction(quitAction);

QMenu *helpMenu = menuBar()->addMenu(tr("&Help"));
helpMenu->addAction(aboutAction);
helpMenu->addAction(aboutQtAction);

connect(quitAction, &QAction::triggered, this, &BookWindow::close);
connect(aboutAction, &QAction::triggered, this, &BookWindow::about);
connect(aboutQtAction, &QAction::triggered, qApp, &QApplication::aboutQt);
}

void BookWindow::about()
{
QMessageBox::about(this, tr("About Books"),
tr("<p>The <b>Books</b> example shows how to use Qt SQL classes "
"with a model/view framework."));
}</div