/*
   mapwidget.cc
   This file is part of the Project::OSiRiON world editor 
   and is distributed under the terms and conditions of 
   the GNU General Public License version 2
*/

#include "mapwidget.h"
#include "mapentity.h"

#include <QPainter>
#include <QMouseEvent>
#include <QWheelEvent>
#include <QDebug>
#include <QtGui>

namespace editor
{

MapWidget::MapWidget(QWidget *parent) : QWidget(parent)
{
	//setMinimumSize(256,256);
	
	// zoom sucks but it works
	mapwidget_zoom = 16;
	
	// center of the map (used for dragging)
	center_x = 0;
	center_y = 0;
}

void MapWidget::wheelEvent(QWheelEvent *event)
{
	if (event->orientation() == Qt::Vertical) {
		int oldzoom = mapwidget_zoom;
		
		mapwidget_zoom -= event->delta() / 120;
		if (mapwidget_zoom < 1)
			mapwidget_zoom = 1;
		else if (mapwidget_zoom > 64) {
			mapwidget_zoom = 64;
		}
		
		center_x = center_x * oldzoom / mapwidget_zoom;
		center_y = center_y * oldzoom / mapwidget_zoom;
		
		resizeChildren();
		update();
		event->accept();
	}
}

void MapWidget::mousePressEvent(QMouseEvent *event)
{
	if (event->button() == Qt::RightButton) {
		dragstart_x = event->pos().x();
		dragstart_y = event->pos().y();
		event->accept();
		is_dragging = true;
	} else {
		is_dragging = false;
	}
}

void MapWidget::mouseReleaseEvent(QMouseEvent *event)
{
	if (event->button() == Qt::RightButton) {
		is_dragging = false;
	}
}

void MapWidget::mouseMoveEvent(QMouseEvent *event)
{
	if (is_dragging) {
		int delta_x = event->pos().x() - dragstart_x;
		int delta_y = event->pos().y() - dragstart_y;
		
		center_x += delta_x;
		center_y += delta_y;
		
		//qDebug() << "dragging " << delta_x << " " << delta_y;
		
		dragstart_x = event->pos().x();
		dragstart_y = event->pos().y();
		
		event->accept();
		
		resizeChildren();
		update();
	}
}

void MapWidget::resizeChildren()
{
	const float scale = (float) width() / (float) (mapwidget_zoom * 256);
	
	for (int i = 0; i < mapwidget_enties.size(); ++i) {
		MapEntity * entity = mapwidget_enties.at(i);
		int radius = (int) (entity->radius() * scale);
		if (radius < 6)
			radius = 6;
		
		int x = width() / 2 - (int) (entity->location(1) * scale) - radius;
		int y = height() / 2 - (int)(entity->location(0) * scale) - radius;
		
		entity->setGeometry(center_x + x, center_y + y, radius * 2 , radius * 2);
		//qDebug() << "Moving entity to " << x << " " << y;
	}

}

void MapWidget::select(MapEntity *entity)
{
	for (int i = 0; i < mapwidget_enties.size(); ++i) {
		
		MapEntity *mapentity = mapwidget_enties.at(i);
		
		if (entity == mapentity) {
			
			entity->set_selected(true);
			//qDebug() << "selected entity " << entity->name();
			emit selected(entity);
			
		} else {
			
			mapentity->set_selected(false);
		}
	}
	update();
}

void MapWidget::resizeEvent (QResizeEvent *event)
{
	resizeChildren();
}

void MapWidget::paintEvent(QPaintEvent *event)
{
	QPen pen(Qt::blue, 1, Qt::SolidLine);
	QPainter painter(this);
	
	painter.setPen(pen);

	// mapwidget_zoom is used to scale from game units to screen coorinates	
	// 1 grid square is 256 game units
	// gridsize is the size of one grid square in screen coordinates
	int gridsize = width() / mapwidget_zoom;
	
	int x = center_x + width() / 2;
	while (x > 0) {
		painter.drawLine(x, 0, x, height());
		x -= gridsize;
	}
	x = center_x + width() / 2 + gridsize;
	while (x <= width()) {
		painter.drawLine(x, 0, x, height());
		x += gridsize;
	}
	
	int y = center_y + height() / 2;
	while (y > 0) {
		painter.drawLine(0, y, width(), y);
		y -= gridsize;
	}
	y = center_y + height() / 2 + gridsize;
	while (y <= height()) {
		painter.drawLine(0, y, width(), y);
		y += gridsize;
	}

	QWidget::paintEvent(event);
}

MapEntity *MapWidget::addEntity()
{
	MapEntity *mapentity = new MapEntity(this);
	mapwidget_enties.append(mapentity);
	
	// connect the MapEntity::clicked() signal to the MapWidget::selected() slot
	connect(mapentity, SIGNAL(clicked(MapEntity *)), this, SLOT(select(MapEntity *)));
	
	mapentity->show();
	
	resizeChildren();
	update();
	
	return mapentity;
}

}