/*
    SPDX-FileCopyrightText: 2001 Felix Rodriguez <frodriguez@users.sourceforge.net>
    SPDX-FileCopyrightText: 2002-2011 Thomas Baumgart <tbaumgart@kde.org>
    SPDX-FileCopyrightText: 2017-2018 Łukasz Wojniłowicz <lukasz.wojnilowicz@gmail.com>
    SPDX-License-Identifier: GPL-2.0-or-later
*/

#include "kmymoneycombo.h"
#include "kmymoneycombo_p.h"

// ----------------------------------------------------------------------------
// QT Includes

#include <QRect>
#include <QStyle>
#include <QPainter>
#include <QKeyEvent>
#include <QList>
#include <QFocusEvent>
#include <QMouseEvent>
#include <QMetaMethod>

// ----------------------------------------------------------------------------
// KDE Includes

#include <KConfig>
#include <KConfigGroup>

// ----------------------------------------------------------------------------
// Project Includes

#include "kmymoneyselector.h"
#include "kmymoneycompletion.h"
#include "kmymoneylineedit.h"

KMyMoneyCombo::KMyMoneyCombo(QWidget *parent) :
    KComboBox(parent),
    d_ptr(new KMyMoneyComboPrivate)
{
}

KMyMoneyCombo::KMyMoneyCombo(bool rw, QWidget *parent) :
    KComboBox(rw, parent),
    d_ptr(new KMyMoneyComboPrivate)
{
    Q_D(KMyMoneyCombo);
    if (rw) {
        d->m_edit = new KMyMoneyLineEdit(this, true);
        setLineEdit(d->m_edit);
    }
}

KMyMoneyCombo::KMyMoneyCombo(KMyMoneyComboPrivate &dd, bool rw, QWidget *parent) :
    KComboBox(rw, parent),
    d_ptr(&dd)
{
    Q_D(KMyMoneyCombo);
    if (rw) {
        d->m_edit = new KMyMoneyLineEdit(this, true);
        setLineEdit(d->m_edit);
    }
}

KMyMoneyCombo::~KMyMoneyCombo()
{
    Q_D(KMyMoneyCombo);
    delete d;
}

void KMyMoneyCombo::setCurrentTextById(const QString& id)
{
    clearEditText();
    if (!id.isEmpty()) {
        QTreeWidgetItem* item = selector()->item(id);
        if (item) {
            setCompletedText(item->text(0));
            setEditText(item->text(0));
        }
    }
}

void KMyMoneyCombo::slotItemSelected(const QString& id)
{
    Q_D(KMyMoneyCombo);
    if (isEditable()) {
        bool blocked = signalsBlocked();
        blockSignals(true);
        setCurrentTextById(id);
        blockSignals(blocked);
    }

    d->m_completion->hide();

    if (d->m_id != id) {
        d->m_id = id;
        emit itemSelected(id);
    }
}

void KMyMoneyCombo::setEditable(bool y)
{
    Q_D(KMyMoneyCombo);
    if (y == isEditable())
        return;

    KComboBox::setEditable(y);

    // make sure we use our own line edit style
    if (y) {
        d->m_edit = new KMyMoneyLineEdit(this, true);
        setLineEdit(d->m_edit);
        d->m_edit->setPalette(palette());
    } else {
        d->m_edit = 0;
    }
}

void KMyMoneyCombo::setPlaceholderText(const QString& hint) const
{
    Q_D(const KMyMoneyCombo);
    if (d->m_edit)
        d->m_edit->setPlaceholderText(hint);
}

void KMyMoneyCombo::paintEvent(QPaintEvent* ev)
{
    Q_D(KMyMoneyCombo);
    KComboBox::paintEvent(ev);
    // if we don't have an edit field, we need to paint the text onto the button
    if (!d->m_edit) {
        if (d->m_completion) {
            QStringList list;
            selector()->selectedItems(list);
            if (!list.isEmpty()) {
                QString str = selector()->item(list[0])->text(0);
                // we only paint, if the text is longer than 1 char. Assumption
                // is that length 1 is the blank case so no need to do painting
                if (str.length() > 1) {
                    QPainter p(this);
                    p.setPen(palette().text().color());
                    QStyleOptionComboBox opt;
                    initStyleOption(&opt);
                    QRect re = style()->subControlRect(QStyle::CC_ComboBox, &opt, QStyle::SC_ComboBoxEditField, this);
                    p.setClipRect(re);
                    p.save();
                    p.setFont(font());
                    QFontMetrics fm(font());
                    int x = re.x(), y = re.y() + fm.ascent();
                    p.drawText(x, y, str);
                    p.restore();
                }
            }
        }
    }
}

void KMyMoneyCombo::mousePressEvent(QMouseEvent *e)
{
    Q_D(KMyMoneyCombo);
    // mostly copied from QCombo::mousePressEvent() and adjusted for our needs
    if (e->button() != Qt::LeftButton)
        return;

    if (((!isEditable() || isInArrowArea(e->globalPos())) && selector()->itemList().count()) && !d->m_completion->isVisible()) {
        d->m_completion->setVisible(true);
    }

    if (d->m_timer.isActive()) {
        d->m_timer.stop();
        d->m_completion->slotMakeCompletion(QString());
        // the above call clears the selection in the selector but maintains the current index, use that index to restore the selection
        QTreeWidget* listView = selector()->listView();
        QModelIndex currentIndex = listView->currentIndex();
        if (currentIndex.isValid()) {
            listView->selectionModel()->select(currentIndex, QItemSelectionModel::Select);
            listView->scrollToItem(listView->currentItem());
        }
    } else {
        KConfig config("kcminputrc");
        KConfigGroup grp = config.group("KDE");
        d->m_timer.setSingleShot(true);
        d->m_timer.start(grp.readEntry("DoubleClickInterval", 400));
    }
}

bool KMyMoneyCombo::isInArrowArea(const QPoint& pos) const
{
    QStyleOptionComboBox opt;
    initStyleOption(&opt);
    QRect arrowRect = style()->subControlRect(QStyle::CC_ComboBox, &opt, QStyle::SC_ComboBoxArrow, this);

    // Correction for motif style, where arrow is smaller
    // and thus has a rect that doesn't fit the button.
    arrowRect.setHeight(qMax(height() - (2 * arrowRect.y()), arrowRect.height()));

    // if the button is not isEditable, it covers the whole widget
    if (!isEditable())
        arrowRect = rect();

    return arrowRect.contains(mapFromGlobal(pos));
}


void KMyMoneyCombo::setSuppressObjectCreation(bool suppress)
{
    Q_D(KMyMoneyCombo);
    d->m_canCreateObjects = !suppress;
}

void KMyMoneyCombo::setCurrentText(const QString& txt)
{
    KComboBox::setItemText(KComboBox::currentIndex(), txt);
}

void KMyMoneyCombo::setCurrentText()
{
    KComboBox::setItemText(KComboBox::currentIndex(), QString());
}

void KMyMoneyCombo::keyPressEvent(QKeyEvent* e)
{
    Q_D(KMyMoneyCombo);
    if ((e->key() == Qt::Key_F4 && e->modifiers() == 0) ||
            (e->key() == Qt::Key_Down && (e->modifiers() & Qt::AltModifier)) ||
            (!isEditable() && e->key() == Qt::Key_Space)) {
        // if we have at least one item in the list, we open the dropdown
        if (selector()->listView()->itemAt(0, 0))
            d->m_completion->setVisible(true);
        e->ignore();
        return;
    }
    KComboBox::keyPressEvent(e);
}

void KMyMoneyCombo::connectNotify(const QMetaMethod & signal)
{
    Q_D(KMyMoneyCombo);
    if (signal != QMetaMethod::fromSignal(&KMyMoneyCombo::createItem)) {
        d->m_canCreateObjects = true;
    }
}

void KMyMoneyCombo::disconnectNotify(const QMetaMethod & signal)
{
    Q_D(KMyMoneyCombo);
    if (signal != QMetaMethod::fromSignal(&KMyMoneyCombo::createItem)) {
        d->m_canCreateObjects = false;
    }
}

void KMyMoneyCombo::focusOutEvent(QFocusEvent* e)
{
    Q_D(KMyMoneyCombo);
    // don't do anything if the focus is lost due to window activation, this way switching
    // windows while typing a category will not popup the category creation dialog
    // also ignore the fact that the focus is lost because of Qt::PopupFocusReason (context menu)
    if (e->reason() == Qt::ActiveWindowFocusReason || e->reason() == Qt::PopupFocusReason)
        return;

    if (d->m_inFocusOutEvent) {
        KComboBox::focusOutEvent(e);
        return;
    }

    d->m_inFocusOutEvent = true;
    if (isEditable() && !currentText().isEmpty()) {
        if (d->m_canCreateObjects) {
            if (!d->m_completion->selector()->contains(currentText())) {
                QString id;
                // announce that we go into a possible dialog to create an object
                // This can be used by upstream widgets to disable filters etc.
                emit objectCreation(true);

                emit createItem(currentText(), id);

                // Announce that we return from object creation
                emit objectCreation(false);

                // update the field to a possibly created object
                d->m_id = id;
                setCurrentTextById(id);

                // make sure the completion does not show through
                d->m_completion->hide();
            }

            // else if we cannot create objects, and the current text is not
            // in the list, then we clear the text and the selection.
        } else if (!d->m_completion->selector()->contains(currentText())) {
            clearEditText();
        }
    }

    KComboBox::focusOutEvent(e);

    // force update of hint and id if there is no text in the widget
    if (isEditable() && currentText().isEmpty()) {
        QString id = d->m_id;
        d->m_id.clear();
        if (!id.isEmpty())
            emit itemSelected(d->m_id);
        update();
    }
    d->m_inFocusOutEvent = false;
}

KMyMoneySelector* KMyMoneyCombo::selector() const
{
    Q_D(const KMyMoneyCombo);
    return d->m_completion->selector();
}

KMyMoneyCompletion* KMyMoneyCombo::completion() const
{
    Q_D(const KMyMoneyCombo);
    return d->m_completion;
}

void KMyMoneyCombo::selectedItems(QStringList& list) const
{
    Q_D(const KMyMoneyCombo);
    if (lineEdit() && lineEdit()->text().length() == 0) {
        list.clear();
    } else {
        d->m_completion->selector()->selectedItems(list);
    }
}

QString KMyMoneyCombo::selectedItem() const
{
    Q_D(const KMyMoneyCombo);
    return d->m_id;
}

void KMyMoneyCombo::setSelectedItem(const QString& id)
{
    Q_D(KMyMoneyCombo);
    d->m_completion->selector()->setSelected(id, true);
    blockSignals(true);
    slotItemSelected(id);
    blockSignals(false);
    update();
}

QSize KMyMoneyCombo::sizeHint() const
{
    return KComboBox::sizeHint();

    // I wanted to use the code below to adjust the size of the combo box
    // according to the largest item in the selector list. Apparently that
    // does not work too well in the enter and edit schedule dialog for
    // the category combo box. So we just use the standard implementation for now.
#if 0
    constPolish();
    int i, w;
    QFontMetrics fm = fontMetrics();

    int maxW = count() ? 18 : 7 * fm.width(QChar('x')) + 18;
    int maxH = qMax(fm.lineSpacing(), 14) + 2;

    w = selector()->optimizedWidth();
    if (w > maxW)
        maxW = w;

    QSize sizeHint = (style().sizeFromContents(QStyle::CT_ComboBox, this,
                      QSize(maxW, maxH)).
                      expandedTo(QApplication::globalStrut()));

    return sizeHint;
#endif
}
