// Copyright (C) 2008  Lukas Lalinsky
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

#include <QGraphicsScene>
#include <QStringList>
#include <QMimeData>
#include <QDebug>
#include "databasetable.h"
#include "databasetableproperties.h"
#include "diagramdocument.h"
#include "column.h"
#include "columnlist.h"
#include "boxsidehub.h"

DatabaseTable::DatabaseTable(DiagramItem *parent)
	: DiagramObject(parent)
{
	setFlag(ItemIsMovable);
	setFlag(ItemIsSelectable);
	setHub(new BoxSideHub(this));
	m_color = Qt::white;
	m_columnList = new ColumnList(this);
	connect(m_columnList, SIGNAL(columnInserted(int)), this, SLOT(updateLayout()));
	connect(m_columnList, SIGNAL(columnRemoved(int)), this, SLOT(updateLayout()));
	connect(m_columnList, SIGNAL(columnChanged(int)), this, SLOT(updateLayout()));
}

QRectF
DatabaseTable::boundingRect() const
{
	return m_outerRect;
}

QList<Column *>
DatabaseTable::primaryKeys() const
{
	QList<Column *> result;
	foreach (Column *column, m_columnList->columns())
		if (column->isPrimaryKey())
			result.append(column);
	return result;
}

void
DatabaseTable::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
	Q_UNUSED(option);
	Q_UNUSED(widget);

	QFont font = scene()->font();
	QFont boldFont = font;
	boldFont.setBold(true);
	QFont boldFontWithUnderline = boldFont;
	boldFontWithUnderline.setUnderline(true);

	QPen pen(QPen(QColor(0, 0, 0)));
	pen.setJoinStyle(Qt::MiterJoin);
	pen.setWidth(1);
	QPen borderPen(pen);
	borderPen.setWidthF(1.3);
	if (!document()->isPrinting() && isSelected()) {
		borderPen.setColor(QColor(0, 96, 255));
	}

	painter->setPen(pen);
	painter->setFont(font);

	painter->fillRect(m_outerRect, color());

	// Draw the table name
	painter->fillRect(m_nameBgRect, QColor(205, 205, 205));
	painter->drawLine(m_nameBgRect.bottomLeft(), m_nameBgRect.bottomRight());
	painter->drawText(m_namePos, m_name);
	
	painter->drawLine(
		QPointF(m_leftSideWidth, m_nameBgRect.bottom()),
		QPointF(m_leftSideWidth, m_outerRect.bottom()));
	
	// Draw the table name
	QPointF colPos = m_firstColPos;
	QPointF leftSizePos = colPos - QPointF(m_leftSideWidth, 0);
	int i = 0;
	foreach (Column *column, m_columnList->columns()) {
		bool isBold = column->isRequired();
		painter->setFont(isBold
			? (column->isPrimaryKey() ? boldFontWithUnderline : boldFont)
			: font);
		painter->drawText(colPos, column->name());
		if (!m_columnLabels[i].isEmpty()) {
			painter->setFont(isBold ? boldFont : font);
			painter->drawText(leftSizePos, m_columnLabels[i]);
		}
		colPos += m_colPosIncrement;
		leftSizePos += m_colPosIncrement;
		++i;
	}
	
	// Draw the outside border
	painter->setPen(borderPen);
	painter->drawRect(m_outerRect);
}

void
DatabaseTable::setName(const QString &name)
{
	m_name = name;
	updateLayout();
	emit propertyChanged("name", name);
}

void
DatabaseTable::setColor(const QColor &color)
{
	m_color = color;
	updateLayout();
	emit propertyChanged("color", color);
}

void
DatabaseTable::setInitialName(int counter)
{
	setName(counter > 1 ? QString("table_%1").arg(counter) : "table");
}

QVariant
DatabaseTable::itemChange(GraphicsItemChange change, const QVariant &value)
{
	if (change == ItemSceneHasChanged) {
		updateLayout();
	}
	if (change == ItemPositionChange) {
		DiagramDocument *model = qobject_cast<DiagramDocument *>(scene());
		if (model) {
			emit model->itemMoved(this);
		}
	}
	if (change == ItemPositionHasChanged) {
		DiagramDocument *model = qobject_cast<DiagramDocument *>(scene());
		if (model)
			emit model->itemHasMoved(this);
	}
	return QGraphicsItem::itemChange(change, value);
}

void
DatabaseTable::updateLayout()
{
	if (!scene())
		return;

	prepareGeometryChange();
	document()->updatePositions(this);

	QFont font = scene()->font();
	QFontMetricsF fontMetrics(font);

	QFont boldFont = font;
	boldFont.setBold(true);
	QFontMetricsF boldFontMetrics(boldFont);

	qreal spaceWidth = fontMetrics.width(' ');
	qreal nameWidth = fontMetrics.width(m_name);
	qreal height = fontMetrics.height();
	
	m_leftSideWidth = fontMetrics.width("PK");

	qreal width = nameWidth + spaceWidth * 2;

	qreal maxColumnWidth = 0;
	m_columnLabels.clear();
	foreach (Column *column, m_columnList->columns()) {
		qreal columnWidth = column->isRequired() ? boldFontMetrics.width(column->name()) : fontMetrics.width(column->name());
		maxColumnWidth = qMax(maxColumnWidth, columnWidth);
		qreal columnLeftSideWidth = 0;
		QStringList label;
		if (column->isPrimaryKey()) {
			label << "PK";
		}
		if (column->isForeignKey()) {
			label << "FK";
		}
		QString labelStr = label.join(",");
		m_columnLabels << labelStr;
		if (column->isRequired()) {
			columnLeftSideWidth = boldFontMetrics.width(labelStr);
		}
		else {
			columnLeftSideWidth = fontMetrics.width(labelStr);
		}
		m_leftSideWidth = qMax(m_leftSideWidth, columnLeftSideWidth);
	}
	m_leftSideWidth += spaceWidth * 2;
	width = qMax(nameWidth + spaceWidth * 4, m_leftSideWidth + maxColumnWidth + spaceWidth * 2);
	
	qreal nameHeight = height + spaceWidth;
	m_outerRect = QRectF(0, 0, width, nameHeight + qMax(0.66, qreal(m_columnList->columnCount())) * fontMetrics.lineSpacing()
		- fontMetrics.leading() + fontMetrics.descent());

	m_nameBgRect = QRectF(0, 0, width, nameHeight);
	m_namePos = QPointF((width - nameWidth) / 2, fontMetrics.ascent() + spaceWidth / 2);

	m_firstColPos = QPointF(m_leftSideWidth + spaceWidth * 1 - 1, nameHeight + fontMetrics.ascent() + 2);
	m_colPosIncrement = QPointF(0, fontMetrics.lineSpacing());

	update();
}

#include "domutils.h"

void
DatabaseTable::loadFromXml(QDomElement element, DiagramDocument *document)
{
	DiagramItem::loadFromXml(element, document);
	QDomElement tableElement = element.firstChildElement("table");
	if (!tableElement.isNull()) {
		setName(readStringElement(tableElement, "name"));
		QColor color(readStringElement(tableElement, "color"));
		setColor(color.isValid() ? color : Qt::white);
		QDomElement columnListElement = tableElement.firstChildElement("column-list");
		QDomElement columnElement = columnListElement.firstChildElement("column");
		while (!columnElement.isNull()) {
			Column *column = new Column();
			column->setName(readStringElement(columnElement, "name"));
			column->setDataType(readStringElement(columnElement, "data-type"));
			column->setRequired(readBoolElement(columnElement, "required"));
			column->setPrimaryKey(readBoolElement(columnElement, "primary-key"));
			column->setNotes(readStringElement(columnElement, "notes"));
			columnList()->appendColumn(column);
			columnElement = columnElement.nextSiblingElement("column");
		}
	}
}

void
DatabaseTable::saveToXml(QDomDocument doc, QDomElement element)
{
	DiagramItem::saveToXml(doc, element);
	QDomElement tableElement = doc.createElement("table");
	element.appendChild(tableElement);
	appendStringElement(doc, tableElement, "name", name());
	appendStringElement(doc, tableElement, "color", color().name());
	QDomElement columnListElement = doc.createElement("column-list");
	tableElement.appendChild(columnListElement);
	foreach (Column *column, columnList()->columns()) {
		QDomElement columnElement = doc.createElement("column");
		columnListElement.appendChild(columnElement);
		appendStringElement(doc, columnElement, "name", column->name());
		appendStringElement(doc, columnElement, "data-type", column->dataType());
		appendBoolElement(doc, columnElement, "required", column->isRequired());
		appendBoolElement(doc, columnElement, "primary-key", column->isPrimaryKey());
		appendStringElement(doc, columnElement, "notes", column->notes());
	}
}

DiagramItemProperties *
DatabaseTable::createPropertiesEditor(QWidget *parent)
{
	return new DatabaseTableProperties(parent);
}