/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2014 CERN
 * @author Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
 *
 * 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, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#include <boost/foreach.hpp>
#include <boost/bind.hpp>

#include <wxPcbStruct.h>

#include <class_board.h>
#include <class_module.h>
#include <class_edge_mod.h>
#include <class_zone.h>
#include <class_draw_panel_gal.h>

#include <view/view_controls.h>
#include <gal/graphics_abstraction_layer.h>

#include <geometry/shape_line_chain.h>

#include "grid_helper.h"

GRID_HELPER::GRID_HELPER ( PCB_BASE_FRAME *aFrame ) : 
	m_frame ( aFrame )
{

}
	
GRID_HELPER::~GRID_HELPER ()
{

}

void GRID_HELPER::SetGrid ( int aSize )
{
	assert ( false );
}

void GRID_HELPER::SetOrigin ( const VECTOR2I& aOrigin )
{
}

VECTOR2I GRID_HELPER::GetGrid ()
{
	PCB_SCREEN *screen = m_frame->GetScreen();

	const wxRealPoint& size = screen->GetGridSize();

	return VECTOR2I ( KiROUND ( size.x ), KiROUND ( size.y ) );
}

VECTOR2I GRID_HELPER::GetOrigin ()
{
	return VECTOR2I ( 0, 0 );
}

void GRID_HELPER::SetAuxAxes ( bool aEnable, const VECTOR2I aOrigin, bool aEnableDiagonal)
{
	if( aEnable )
		m_auxAxis = aOrigin;
	else
		m_auxAxis = boost::optional <VECTOR2I> ();

	m_diagonalAuxAxesEnable = aEnable;	
}

VECTOR2I GRID_HELPER::Align ( const VECTOR2I& aPoint )
{
	const VECTOR2D gridOffset ( GetOrigin () );
	const VECTOR2D gridSize ( GetGrid() );

	VECTOR2I nearest ( round( ( aPoint.x - gridOffset.x ) / gridSize.x ) * gridSize.x + gridOffset.x,
                       round( ( aPoint.y - gridOffset.y ) / gridSize.y ) * gridSize.y + gridOffset.y );

	if ( !m_auxAxis )
		return nearest;

	if ( std::abs ( m_auxAxis->x - aPoint.x) < std::abs ( nearest.x - aPoint.x ) )
		nearest.x = m_auxAxis->x;

	if ( std::abs ( m_auxAxis->y - aPoint.y) < std::abs ( nearest.y - aPoint.y ) )
		nearest.y = m_auxAxis->y;

	return nearest;
}

VECTOR2I GRID_HELPER::BestDragOrigin ( const VECTOR2I &aMousePos, BOARD_ITEM *aItem )
{
    clearAnchors();
   	computeAnchors( aItem, aMousePos );
    
    double worldScale = m_frame->GetGalCanvas()->GetGAL()->GetWorldScale();
    double lineSnapMinCornerDistance = 50.0 / worldScale;

    ANCHOR* nearestOutline = nearestAnchor ( aMousePos, OUTLINE, LSET::AllLayersMask() );
	ANCHOR* nearestCorner = nearestAnchor ( aMousePos, CORNER, LSET::AllLayersMask() );
	ANCHOR* nearestOrigin = nearestAnchor ( aMousePos, ORIGIN, LSET::AllLayersMask() );
	ANCHOR* best = NULL;
	double minDist = std::numeric_limits<double>::max(); 	

	if (nearestOrigin)
	{
		minDist = nearestOrigin->Distance(aMousePos);
		best = nearestOrigin;
	}

	if (nearestCorner)
	{
		double dist = nearestCorner->Distance(aMousePos);
		if (dist < minDist)
		{
			minDist = dist;
			best = nearestCorner;
		}
	}

	if (nearestOutline)
    {
    	double dist = nearestOutline->Distance(aMousePos);
    	if (minDist > lineSnapMinCornerDistance && dist < minDist)
    		best = nearestOutline;
    }

    return best ? best->pos : aMousePos;
}

std::set<BOARD_ITEM *> GRID_HELPER::queryVisible ( const BOX2I& aArea )
{
	std::set <BOARD_ITEM *> items;

    std::vector<KIGFX::VIEW::LAYER_ITEM_PAIR> selectedItems;
	std::vector<KIGFX::VIEW::LAYER_ITEM_PAIR>::iterator it, it_end;

	m_frame->GetGalCanvas()->GetView()->Query( aArea, selectedItems );         // Get the list of selected items

  	for( it = selectedItems.begin(), it_end = selectedItems.end(); it != it_end; ++it )
    {
    	BOARD_ITEM* item = static_cast<BOARD_ITEM*>( it->first );
    	if( item->ViewIsVisible() )
    		items.insert ( item );
    }

    return items;
}

VECTOR2I GRID_HELPER::BestSnapAnchor ( const VECTOR2I &aOrigin, BOARD_ITEM *aDraggedItem )
{
	double worldScale = m_frame->GetGalCanvas()->GetGAL()->GetWorldScale();
    int snapRange = (int) (100.0 / worldScale);

    BOX2I bb ( VECTOR2I ( aOrigin.x - snapRange / 2, aOrigin.y - snapRange/2) , VECTOR2I  (snapRange, snapRange) );

    clearAnchors();

    BOOST_FOREACH ( BOARD_ITEM *item, queryVisible ( bb ) )
    {
        computeAnchors(item, aOrigin);
    }

	LSET layers ( aDraggedItem->GetLayer() );
    ANCHOR *nearest = nearestAnchor ( aOrigin, CORNER | SNAPPABLE, layers );

    VECTOR2I nearestGrid = Align ( aOrigin );
    double gridDist = (nearestGrid - aOrigin).EuclideanNorm();
    if (nearest)
    {
     	double snapDist = nearest->Distance ( aOrigin );

	    if(nearest && snapDist < gridDist)
    	 	return nearest->pos;
   	}

   	return nearestGrid;
}

void GRID_HELPER::computeAnchors ( BOARD_ITEM *aItem, const VECTOR2I& aRefPos )
{
	VECTOR2I origin;

    
    switch ( aItem->Type() )
    {
        case PCB_MODULE_T:
        {
             MODULE *mod = static_cast <MODULE *> (aItem);
			addAnchor ( mod->GetPosition(), ORIGIN | SNAPPABLE, mod );

            for (D_PAD *pad = mod->Pads(); pad; pad = pad->Next() )
            	addAnchor ( pad->GetPosition(), CORNER | SNAPPABLE, pad );
           
            break;
        }

        case PCB_MODULE_EDGE_T:
        case PCB_LINE_T:
        {
            DRAWSEGMENT *dseg = static_cast <DRAWSEGMENT*> (aItem);
            VECTOR2I start = dseg->GetStart();
            VECTOR2I end = dseg->GetEnd();
 			//LAYER_ID layer = dseg->GetLayer();


            switch( dseg->GetShape() )
            {
                case S_CIRCLE:
                {
                    int r = (start - end).EuclideanNorm();
                    
                    addAnchor ( start, ORIGIN | SNAPPABLE, dseg );
                    addAnchor ( start + VECTOR2I ( -r, 0 ) , OUTLINE | SNAPPABLE, dseg );
                    addAnchor ( start + VECTOR2I ( r, 0 ) , OUTLINE | SNAPPABLE, dseg );
					addAnchor ( start + VECTOR2I ( 0, -r ) , OUTLINE | SNAPPABLE, dseg);
                    addAnchor ( start + VECTOR2I ( 0, r ) , OUTLINE | SNAPPABLE, dseg );
                    break;
                }

                case S_ARC:
                {
                    origin = dseg->GetCenter();
                  	addAnchor ( dseg->GetArcStart(), CORNER | SNAPPABLE, dseg );
                    addAnchor ( dseg->GetArcEnd(), CORNER | SNAPPABLE, dseg );
					addAnchor ( origin, ORIGIN | SNAPPABLE, dseg );
					break;    
                }

                case S_SEGMENT:
                {
                    origin.x = start.x + ( start.x - end.x ) / 2;
                    origin.y = start.y + ( start.y - end.y ) / 2;
                 	addAnchor ( start, CORNER | SNAPPABLE, dseg );
                    addAnchor ( end, CORNER | SNAPPABLE, dseg );
					addAnchor ( origin, ORIGIN, dseg );
                    break;
                }  

                default:
                {
                    origin = dseg->GetStart();
					addAnchor ( origin, ORIGIN | SNAPPABLE, dseg );
                    break;
                }
            }
            break;
        }

        case PCB_TRACE_T:
        {
            TRACK *track = static_cast <TRACK*> (aItem);
            VECTOR2I start = track->GetStart();
            VECTOR2I end = track->GetEnd();
            origin.x = start.x + ( start.x - end.x ) / 2;
            origin.y = start.y + ( start.y - end.y ) / 2;
           	addAnchor ( start, CORNER | SNAPPABLE, track );
            addAnchor ( end, CORNER | SNAPPABLE, track );
			addAnchor ( origin, ORIGIN, track);
            break;
        }  

        case PCB_ZONE_AREA_T:
        {
            const CPolyLine* outline = static_cast<const ZONE_CONTAINER*>( aItem )->Outline();
            int cornersCount = outline->GetCornersCount();
            
            SHAPE_LINE_CHAIN lc;
            lc.SetClosed ( true );
            
            for( int i = 0; i < cornersCount; ++i )
            {
            	const VECTOR2I p ( outline->GetPos( i ) );
	           	addAnchor ( p, CORNER, aItem );
				lc.Append ( p );
			}

			addAnchor( lc.NearestPoint ( aRefPos ), OUTLINE, aItem );

            break;
        }

        case PCB_MODULE_TEXT_T:
        case PCB_TEXT_T:
			addAnchor ( aItem->GetPosition(), ORIGIN, aItem );
        default:
            

        break;
   }

}

GRID_HELPER::ANCHOR* GRID_HELPER::nearestAnchor ( VECTOR2I aPos, int aFlags, LSET aMatchLayers )
{
	double minDist = std::numeric_limits<double>::max();
 	ANCHOR *best = NULL;

 	BOOST_FOREACH( ANCHOR& a, m_anchors )
 	{
 		if ( !aMatchLayers [ a.item->GetLayer() ]	)
 			continue;

 		if ( ( aFlags & a.flags ) != aFlags )
 			continue;

 		double dist = a.Distance(aPos);

 		if(dist < minDist)
 			{
 				minDist = dist;
 				best = &a;
 			}
 	}

 	return best;

}