/*  View.cpp
 *
 *  Copyright (C) 2013  Jim Evins <evins@snaught.com>
 *
 *  This file is part of gLabels-qt.
 *
 *  gLabels-qt 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 3 of the License, or
 *  (at your option) any later version.
 *
 *  gLabels-qt 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 gLabels-qt.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "View.h"

#include <cmath>
#include <iostream>


namespace
{
	const int    nZoomLevels = 14;
	const double zoomLevels[nZoomLevels] = { 8, 6, 4, 3, 2, 1.5, 1, 0.75, 0.67, 0.50, 0.33, 0.25, 0.15, 0.10 };

	const double ZOOM_TO_FIT_PAD = 16;
}


namespace glabels
{

	View::View( QWidget *parent ) : QGraphicsView(parent)
	{
		setZoomReal( 1, false );
		mModel         = 0;

		mScene = new QGraphicsScene();
		setScene( mScene );
	}


	void View::setModel( LabelModel* model )
	{
		mModel = model;

		foreach (LabelModelObject* object, model->objectList() )
		{
			QGraphicsItem* item = object->createGraphicsItem();
			mScene->addItem( item );
		}
	}


	void View::zoomIn()
	{
		// Find closest standard zoom level to our current zoom
		// Start with 2nd largest scale
		int i_min = 1;
		double dist_min = fabs( zoomLevels[1] - mZoom );

		for ( int i = 2; i < nZoomLevels; i++ )
		{
			double dist = fabs( zoomLevels[i] - mZoom );
			if ( dist < dist_min )
			{
				i_min = i;
				dist_min = dist;
			}
		}

		// Zoom in one notch
		setZoomReal( zoomLevels[i_min-1], false );
	}


	void View::zoomOut()
	{
		// Find closest standard zoom level to our current zoom
		// Start with largest scale, end on 2nd smallest
		int i_min = 0;
		double dist_min = fabs( zoomLevels[0] - mZoom );

		for ( int i = 1; i < (nZoomLevels-1); i++ )
		{
			double dist = fabs( zoomLevels[i] - mZoom );
			if ( dist < dist_min )
			{
				i_min = i;
				dist_min = dist;
			}
		}

		// Zoom out one notch
		setZoomReal( zoomLevels[i_min+1], false );
	}


	void View::zoom1To1()
	{
		setZoomReal( 1.0, false );
	}


	void View::zoomToFit()
	{
		double x_scale = (72.0/physicalDpiY()) * ( width() - ZOOM_TO_FIT_PAD ) / mModel->w();
		double y_scale = (72.0/physicalDpiY()) * ( height() - ZOOM_TO_FIT_PAD ) / mModel->h();
		double newZoom = min( x_scale, y_scale );

		// Limits
		newZoom = min( newZoom, zoomLevels[0] );
		newZoom = max( newZoom, zoomLevels[nZoomLevels-1] );

		setZoomReal( newZoom, true );
	}


	bool View::isZoomMax() const
	{
		return ( mZoom >= zoomLevels[0] );
	}


	bool View::isZoomMin() const
	{
		return ( mZoom <= zoomLevels[nZoomLevels-1] );
	}


	void View::setZoomReal( double zoom, bool zoomToFitFlag )
	{
		mZoom          = zoom;
		mZoomToFitFlag = zoomToFitFlag;

		resetTransform();
		scale( mZoom*physicalDpiX()/72.0, mZoom*physicalDpiY()/72.0 );

		emit zoomChanged();
	}


	void View::resizeEvent( QResizeEvent *event )
	{
		if ( mZoomToFitFlag )
		{
			zoomToFit();
		}
	}

}