/* This file is part of the KDE project
   Copyright (C) 2006-2007 Jaroslaw Staniek <js@iidea.pl>

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/

#include "kexidbcombobox.h"
#include "kexidblineedit.h"
#include "../kexiformscrollview.h"

#include <kcombobox.h>
#include <kdebug.h>
#include <kapplication.h>

#include <qmetaobject.h>
#include <qpainter.h>
#include <qstyle.h>
#include <qdrawutil.h>
#include <qptrdict.h>
#include <qcursor.h>

#include <kexidb/queryschema.h>
#include <widget/tableview/kexicomboboxpopup.h>
#include <widget/tableview/kexicelleditorfactory.h>
#include <kexiutils/utils.h>

//! @internal
class KexiDBComboBox::Private
{
	public:
		Private()
		 : popup(0)
		 , visibleColumnInfo(0)
		 , subWidgetsWithDisabledEvents(0)
		 , isEditable(false)
		 , buttonPressed(false)
		 , mouseOver(false)
		 , dataEnteredByHand(true)
		{
		}
		~Private()
		{
			delete subWidgetsWithDisabledEvents;
			subWidgetsWithDisabledEvents = 0;
		}

	KexiComboBoxPopup *popup;
	KComboBox *paintedCombo; //!< fake combo used only to pass it as 'this' for QStyle (because styles use <static_cast>)
	QSize sizeHint; //!< A cache for KexiDBComboBox::sizeHint(), 
	                //!< rebuilt by KexiDBComboBox::fontChange() and KexiDBComboBox::styleChange()
	KexiDB::QueryColumnInfo* visibleColumnInfo;
	QPtrDict<char> *subWidgetsWithDisabledEvents; //! used to collect subwidget and its children (if isEditable is false)
	bool isEditable : 1; //!< true is the combo box is editable
	bool buttonPressed : 1;
	bool mouseOver : 1;
	bool dataEnteredByHand : 1;
	bool designMode : 1;
};

//-------------------------------------

KexiDBComboBox::KexiDBComboBox(QWidget *parent, const char *name, bool designMode)
 : KexiDBAutoField(parent, name, designMode, NoLabel)
 , KexiComboBoxBase()
 , d(new Private())
{
	setMouseTracking(true);
	setFocusPolicy(WheelFocus);
	installEventFilter(this);
	d->designMode = designMode;
	d->paintedCombo = new KComboBox(this);
	d->paintedCombo->hide();
	d->paintedCombo->move(0,0);
}

KexiDBComboBox::~KexiDBComboBox()
{
	delete d;
}

KexiComboBoxPopup *KexiDBComboBox::popup() const
{
	return d->popup;
}

void KexiDBComboBox::setPopup(KexiComboBoxPopup *popup)
{
	d->popup = popup;
}

void KexiDBComboBox::setEditable(bool set)
{
	if (d->isEditable == set)
		return;
	d->isEditable = set;
	d->paintedCombo->setEditable(set);
	if (set)
		createEditor();
	else {
		delete m_subwidget;
		m_subwidget = 0;
	}
	update();
}

bool KexiDBComboBox::isEditable() const
{
	return d->isEditable;
}

void KexiDBComboBox::paintEvent( QPaintEvent * )
{
	QPainter p( this );
	QColorGroup cg( palette().active() );
//	if ( hasFocus() )
//		cg.setColor(QColorGroup::Base, cg.highlight());
//	else
		cg.setColor(QColorGroup::Base, paletteBackgroundColor()); //update base color using (reimplemented) bg color
	p.setPen(cg.text());

	QStyle::SFlags flags = QStyle::Style_Default;
	if (isEnabled())
		flags |= QStyle::Style_Enabled;
	if (hasFocus())
		flags |= QStyle::Style_HasFocus;
	if (d->mouseOver)
		flags |= QStyle::Style_MouseOver;

	if ( width() < 5 || height() < 5 ) {
		qDrawShadePanel( &p, rect(), cg, FALSE, 2, &cg.brush( QColorGroup::Button ) );
		return;
	}

//! @todo support reverse layout
//bool reverse = QApplication::reverseLayout();
	style().drawComplexControl( QStyle::CC_ComboBox, &p, d->paintedCombo /*this*/, rect(), cg,
		flags, (uint)QStyle::SC_All, 
		(d->buttonPressed ? QStyle::SC_ComboBoxArrow : QStyle::SC_None )
	);

	if (d->isEditable) {
		//if editable, editor paints itself, nothing to do
	}
	else { //not editable: we need to paint the current item
		QRect editorGeometry( this->editorGeometry() );
		if ( hasFocus() ) {
			if (0==qstrcmp(style().name(), "windows")) //a hack
				p.fillRect( editorGeometry, cg.brush( QColorGroup::Highlight ) );
			QRect r( QStyle::visualRect( style().subRect( QStyle::SR_ComboBoxFocusRect, d->paintedCombo ), this ) );
			r = QRect(r.left()-1, r.top()-1, r.width()+2, r.height()+2); //enlare by 1 pixel each side to avoid covering by the subwidget
			style().drawPrimitive( QStyle::PE_FocusRect, &p, 
				r, cg, flags | QStyle::Style_FocusAtBorder, QStyleOption(cg.highlight()));
		}
		//todo
	}
}

QRect KexiDBComboBox::editorGeometry() const
{
	QRect r( QStyle::visualRect(
		style().querySubControlMetrics(QStyle::CC_ComboBox, d->paintedCombo,
		QStyle::SC_ComboBoxEditField), d->paintedCombo ) );
	
	//if ((height()-r.bottom())<6)
	//	r.setBottom(height()-6);
	return r;
}

void KexiDBComboBox::createEditor()
{
	KexiDBAutoField::createEditor();
	if (m_subwidget) {
		m_subwidget->setGeometry( editorGeometry() );
		if (!d->isEditable) {
			m_subwidget->setCursor(QCursor(Qt::ArrowCursor)); // widgets like listedit have IbeamCursor, we don't want that
//! @todo Qt4: set transparent background, for now we're setting button color
			QPalette subwidgetPalette( m_subwidget->palette() );
			subwidgetPalette.setColor(QPalette::Active, QColorGroup::Base, 
				subwidgetPalette.color(QPalette::Active, QColorGroup::Button));
			m_subwidget->setPalette( subwidgetPalette );
			if (d->subWidgetsWithDisabledEvents)
				d->subWidgetsWithDisabledEvents->clear();
			else
				d->subWidgetsWithDisabledEvents = new QPtrDict<char>();
			d->subWidgetsWithDisabledEvents->insert(m_subwidget, (char*)1);
			m_subwidget->installEventFilter(this);
			QObjectList *l = m_subwidget->queryList( "QWidget" );
			for ( QObjectListIt it( *l ); it.current(); ++it ) {
				d->subWidgetsWithDisabledEvents->insert(it.current(), (char*)1);
				it.current()->installEventFilter(this);
			}
			delete l;
		}
	}
	updateGeometry();
}

void KexiDBComboBox::setLabelPosition(LabelPosition position)
{
	if(m_subwidget) {
		if (-1 != m_subwidget->metaObject()->findProperty("frameShape", true))
			m_subwidget->setProperty("frameShape", QVariant((int)QFrame::NoFrame));
		m_subwidget->setGeometry( editorGeometry() );
	}
//		KexiSubwidgetInterface *subwidgetInterface = dynamic_cast<KexiSubwidgetInterface*>((QWidget*)m_subwidget);
		// update size policy
//		if (subwidgetInterface && subwidgetInterface->subwidgetStretchRequired(this)) {
			QSizePolicy sizePolicy( this->sizePolicy() );
			if(position == Left)
				sizePolicy.setHorData( QSizePolicy::Minimum );
			else
				sizePolicy.setVerData( QSizePolicy::Minimum );
			//m_subwidget->setSizePolicy(sizePolicy);
			setSizePolicy(sizePolicy);
		//}
//	}
}

QRect KexiDBComboBox::buttonGeometry() const
{
	QRect arrowRect( 
		style().querySubControlMetrics( QStyle::CC_ComboBox, d->paintedCombo, QStyle::SC_ComboBoxArrow) );
	arrowRect = QStyle::visualRect(arrowRect, d->paintedCombo);
	arrowRect.setHeight( QMAX(  height() - (2 * arrowRect.y()), arrowRect.height() ) ); // a fix for Motif style
	return arrowRect;
}

bool KexiDBComboBox::handleMousePressEvent(QMouseEvent *e)
{
	if ( e->button() != Qt::LeftButton || d->designMode )
		return true;
/*todo	if ( m_discardNextMousePress ) {
		d->discardNextMousePress = FALSE;
		return;
    }*/

	if ( /*count() &&*/ ( !isEditable() || buttonGeometry().contains( e->pos() ) ) ) {
		d->buttonPressed = false;

/*	if ( d->usingListBox() ) {
	    listBox()->blockSignals( TRUE );
	    qApp->sendEvent( listBox(), e ); // trigger the listbox's autoscroll
	    listBox()->setCurrentItem(d->current);
	    listBox()->blockSignals( FALSE );
	    popup();
	    if ( arrowRect.contains( e->pos() ) ) {
		d->arrowPressed = TRUE;
		d->arrowDown    = TRUE;
		repaint( FALSE );
	    }
	} else {*/
		showPopup();
		return true;
	}
	return false;
}

bool KexiDBComboBox::handleKeyPressEvent(QKeyEvent *ke)
{
	const int k = ke->key();
	const bool dropDown = (ke->state() == Qt::NoButton && ((k==Qt::Key_F2 && !d->isEditable) || k==Qt::Key_F4))
		|| (ke->state() == Qt::AltButton && k==Qt::Key_Down);
	const bool escPressed = ke->state() == Qt::NoButton && k==Qt::Key_Escape;
	const bool popupVisible =  popup() && popup()->isVisible();
	if ((dropDown || escPressed) && popupVisible) {
		popup()->hide();
		return true;
	}
	else if (dropDown && !popupVisible) {
		d->buttonPressed = false;
		showPopup();
		return true;
	}
	else if (popupVisible) {
		const bool enterPressed = k==Qt::Key_Enter || k==Qt::Key_Return;
		if (enterPressed/* && m_internalEditorValueChanged*/) {
			acceptPopupSelection();
			return true;
		}
		return handleKeyPressForPopup( ke );
	}

	return false;
}

bool KexiDBComboBox::keyPressed(QKeyEvent *ke)
{
	if (KexiDBAutoField::keyPressed(ke))
		return true;

	const int k = ke->key();
	const bool popupVisible =  popup() && popup()->isVisible();
	const bool escPressed = ke->state() == Qt::NoButton && k==Qt::Key_Escape;
	if (escPressed && popupVisible) {
		popup()->hide();
		return true;
	}
	if (ke->state() == Qt::NoButton && (k==Qt::Key_PageDown || k==Qt::Key_PageUp) && popupVisible)
		return true;
	return false;
}

void KexiDBComboBox::mousePressEvent( QMouseEvent *e )
{
	if (handleMousePressEvent(e))
		return;

//	QTimer::singleShot( 200, this, SLOT(internalClickTimeout()));
//	d->shortClick = TRUE;
//  }
	KexiDBAutoField::mousePressEvent( e );
}

void KexiDBComboBox::mouseDoubleClickEvent( QMouseEvent *e )
{
	mousePressEvent( e );
}

bool KexiDBComboBox::eventFilter( QObject *o, QEvent *e )
{
	if (o==this) {
		if (e->type()==QEvent::Resize) {
			d->paintedCombo->resize(size());
			if (m_subwidget)
				m_subwidget->setGeometry( editorGeometry() );
		}
		else if (e->type()==QEvent::Enter) {
			if (!d->isEditable 
				|| /*over button if editable combo*/buttonGeometry().contains( static_cast<QMouseEvent*>(e)->pos() )) 
			{
				d->mouseOver = true;
				update();
			}
		}
		else if (e->type()==QEvent::MouseMove) {
			if (d->isEditable) {
				const bool overButton = buttonGeometry().contains( static_cast<QMouseEvent*>(e)->pos() );
				if (overButton != d->mouseOver) {
					d->mouseOver = overButton;
					update();
				}
			}
		}
		else if (e->type()==QEvent::Leave) {
			d->mouseOver = false;
			update();
		}
		else if (e->type()==QEvent::KeyPress) {
			// handle F2/F4
			if (handleKeyPressEvent(static_cast<QKeyEvent*>(e)))
				return true;
		}
		else if (e->type()==QEvent::FocusOut) {
			if (popup() && popup()->isVisible()) {
				popup()->hide();
				undoChanges();
			}
		}
	}
	else if (!d->isEditable && d->subWidgetsWithDisabledEvents && d->subWidgetsWithDisabledEvents->find(o)) {
		if (e->type()==QEvent::MouseButtonPress) {
			// clicking the subwidget should mean the same as clicking the combo box (i.e. show the popup)
			if (handleMousePressEvent(static_cast<QMouseEvent*>(e)))
				return true;
		}
		else if (e->type()==QEvent::KeyPress) {
			if (handleKeyPressEvent(static_cast<QKeyEvent*>(e)))
				return true;
		}
		return e->type()!=QEvent::Paint;
	}
	return KexiDBAutoField::eventFilter( o, e );
}

bool KexiDBComboBox::subwidgetStretchRequired(KexiDBAutoField* autoField) const
{
	Q_UNUSED(autoField);
	return true;
}

void KexiDBComboBox::setPaletteBackgroundColor( const QColor & color )
{
	KexiDBAutoField::setPaletteBackgroundColor(color);
	QPalette pal(palette());
	QColorGroup cg(pal.active());
	pal.setColor(QColorGroup::Base, red);
	pal.setColor(QColorGroup::Background, red);
	pal.setActive(cg);
	QWidget::setPalette(pal);
	update();
}

bool KexiDBComboBox::valueChanged()
{
	kdDebug() << "KexiDataItemInterface::valueChanged(): " << m_origValue.toString() << " ? " << value().toString() << endl;
	return m_origValue != value();
}

void
KexiDBComboBox::setColumnInfo(KexiDB::QueryColumnInfo* cinfo)
{
	KexiFormDataItemInterface::setColumnInfo(cinfo);
}

void KexiDBComboBox::setVisibleColumnInfo(KexiDB::QueryColumnInfo* cinfo)
{
	d->visibleColumnInfo = cinfo;
	// we're assuming we already have columnInfo()
	setColumnInfoInternal(columnInfo(), d->visibleColumnInfo);
}

KexiDB::QueryColumnInfo* KexiDBComboBox::visibleColumnInfo() const
{
	return d->visibleColumnInfo;
}

void KexiDBComboBox::moveCursorToEndInInternalEditor()
{
	if (d->isEditable && m_moveCursorToEndInInternalEditor_enabled)
		moveCursorToEnd();
}

void KexiDBComboBox::selectAllInInternalEditor()
{
	if (d->isEditable && m_selectAllInInternalEditor_enabled)
		selectAll();
}

void KexiDBComboBox::setValueInternal(const QVariant& add, bool removeOld)
{
	//// use KexiDBAutoField instead of KexiComboBoxBase::setValueInternal 
	//// expects existing popup(), but we want to have delayed creation
	if (popup())
		popup()->hide();
	KexiComboBoxBase::setValueInternal(add, removeOld);
}

void KexiDBComboBox::setVisibleValueInternal(const QVariant& value)
{
	KexiFormDataItemInterface *iface = dynamic_cast<KexiFormDataItemInterface*>((QWidget*)m_subwidget);
	if(iface)
		iface->setValue(value, QVariant(), false /*!removeOld*/);
}

QVariant KexiDBComboBox::visibleValue()
{
	return KexiComboBoxBase::visibleValue();
}

void KexiDBComboBox::setValueInInternalEditor(const QVariant& value)
{
	if (!m_setValueInInternalEditor_enabled)
		return;
	KexiFormDataItemInterface *iface = dynamic_cast<KexiFormDataItemInterface*>((QWidget*)m_subwidget);
	if(iface)
		iface->setValue(value, QVariant(), false/*!removeOld*/);
}

QVariant KexiDBComboBox::valueFromInternalEditor()
{
	return KexiDBAutoField::value();
}

QPoint KexiDBComboBox::mapFromParentToGlobal(const QPoint& pos) const
{
//	const KexiFormScrollView* view = KexiUtils::findParentConst<const KexiFormScrollView>(this, "KexiFormScrollView"); 
	if (!parentWidget())
		return QPoint(-1,-1);
	return parentWidget()->mapToGlobal(pos);
//	return view->viewport()->mapToGlobal(pos);
}

int KexiDBComboBox::popupWidthHint() const
{
	return width(); //popup() ? popup()->width() : 0;
}

void KexiDBComboBox::fontChange( const QFont & oldFont )
{
	d->sizeHint = QSize(); //force rebuild the cache
	KexiDBAutoField::fontChange(oldFont);
}

void KexiDBComboBox::styleChange( QStyle& oldStyle )
{
	KexiDBAutoField::styleChange( oldStyle );
	d->sizeHint = QSize(); //force rebuild the cache
	if (m_subwidget)
		m_subwidget->setGeometry( editorGeometry() );
}

QSize KexiDBComboBox::sizeHint() const
{
	if ( isVisible() && d->sizeHint.isValid() )
		return d->sizeHint;

	const int maxWidth = 7 * fontMetrics().width(QChar('x')) + 18;
	const int maxHeight = QMAX( fontMetrics().lineSpacing(), 14 ) + 2;
	d->sizeHint = (style().sizeFromContents(QStyle::CT_ComboBox, d->paintedCombo,
		QSize(maxWidth, maxHeight)).expandedTo(QApplication::globalStrut()));

	return d->sizeHint;
}

void KexiDBComboBox::editRequested()
{
}

void KexiDBComboBox::acceptRequested()
{
	signalValueChanged();
}

void KexiDBComboBox::slotRowAccepted(KexiTableItem *item, int row)
{
	d->dataEnteredByHand = false;
	KexiComboBoxBase::slotRowAccepted(item, row);
	d->dataEnteredByHand = true;
}

void KexiDBComboBox::beforeSignalValueChanged()
{
	if (d->dataEnteredByHand)	{
		KexiFormDataItemInterface *iface = dynamic_cast<KexiFormDataItemInterface*>((QWidget*)m_subwidget);
		if (iface) {
			slotInternalEditorValueChanged( iface->value() );
		}
	}
}

void KexiDBComboBox::undoChanges()
{
	KexiDBAutoField::undoChanges();
	KexiComboBoxBase::undoChanges();
}

#include "kexidbcombobox.moc"