/*
 * KiRouter - a push-and-(sometimes-)shove PCB router
 *
 * Copyright (C) 2013  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 3 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, see <http://www.gnu.or/licenses/>.
 */
#ifndef __PNS_NODE_H
#define __PNS_NODE_H

#include <vector>
#include <list>

#include <boost/unordered_set.hpp>
#include <boost/unordered_map.hpp>
#include <boost/optional.hpp>
#include <boost/smart_ptr.hpp>

#include <geometry/shape.h>
#include <geometry/shape_line_chain.h>
#include <geometry/shape_index.h>

#include "pns_item.h"
#include "pns_joint.h"
#include "pns_itemset.h"

class PNS_SEGMENT;
class PNS_LINE;
class PNS_SOLID;
class PNS_VIA;
class PNS_RATSNEST;
class PNS_INDEX;

using boost::shared_ptr;

class PNS_CLEARANCE_FUNC {
	public:
		virtual int operator() ( const PNS_ITEM *a , const PNS_ITEM *b) = 0;
};

/**
 * Struct PNS_OBSTACLE
 *
 * Holds an object colliding with another object, along with
 * some useful data about the collision.
 **/
struct PNS_OBSTACLE 
{
	///> Item we search collisions with
	PNS_ITEM *head;
		
	///> Item found to be colliding with head 
	PNS_ITEM *item;

	///> Hull of the colliding item
	SHAPE_LINE_CHAIN hull;
	
	///> First and last intersection point between the head item and the hull of the 
	//// colliding item
	VECTOR2I ip_first, ip_last;
	
	///> ... and the distance thereof
	int dist_first, dist_last;
};

/**
 * Class PNS_NODE
 *
 * Keeps the router "world" - i.e. all the tracks, vias, solids in a hierarchical and indexed way. 
 * Features:
 * - spatial-indexed container for PCB item shapes
 * - collision search (with clearance checking)
 * - assembly of lines connecting joints, finding loops and unique paths
 * - lightweight cloning/branching (for recursive optimization and shove springback)
 **/

class PNS_NODE {

public:
	
	typedef boost::optional<PNS_OBSTACLE> OptObstacle;
	typedef std::vector<PNS_ITEM *> ItemVector;
	typedef std::vector<PNS_OBSTACLE> Obstacles;
	typedef boost::optional<PNS_JOINT> OptJoint;

	PNS_NODE ();
	~PNS_NODE ();

	///> Returns the expected clearance between items a and b.
	int GetClearance(const PNS_ITEM *a, const PNS_ITEM *b) const;
	
	///> Returns the pre-set worst case clearance between any pair of items
	int GetMaxClearance() const
	{
		return m_maxClearance;
	}

	void SetMaxClearance( int aClearance ) 
	{
		m_maxClearance = aClearance;
	}

	void SetClearanceFunctor (PNS_CLEARANCE_FUNC *aFunc)
	{
		m_clearanceFunctor = aFunc;
	}

	///> Finds items that collide with aItem and stores collision information in aObstacles.
	int QueryColliding( const PNS_ITEM* aItem, Obstacles& aObstacles, int aKindMask = PNS_ITEM::ANY, int aLimitCount = -1);

	///> Finds the nearest item that collides with aItem.
	OptObstacle NearestObstacle( const PNS_LINE *aItem, int aKindMask = PNS_ITEM::ANY);

	///> Checks if the item collides with anything else in the world, and returns it if so.
	OptObstacle CheckColliding ( const PNS_ITEM *aItem, int aKindMask = PNS_ITEM::ANY);

	///> Checks if two items collide [deprecated].
	bool CheckColliding( const PNS_ITEM *aItemA, const PNS_ITEM *aItemB, int aKindMask = PNS_ITEM::ANY);

	///> Hit detection
	const PNS_ITEMSET HitTest( const VECTOR2I& aPoint );

	void Add(PNS_ITEM *aItem);
	void Remove(PNS_ITEM *aItem);
	void Replace(PNS_ITEM *aOldItem, PNS_ITEM *aNewItem);

	///> Creates a lightweight copy ("branch") of self. Note that if there are any branches
	///  in use, their parents must NOT be deleted.
	PNS_NODE *Branch();

	///> Assembles a line connecting two non-trivial joints the segment aSeg belongs to.
	PNS_LINE *AssembleLine(PNS_SEGMENT *aSeg, const OptJoint& a = OptJoint(), const OptJoint& b = OptJoint());
	
	///> Dumps the contents and joints structure	
	void Dump(bool aLong = false);

	///> Returns the number of joints
	int JointCount() const
	{
		return m_joints.size();
	}

	///> Returns the lists of items removed and added in this branch, with respect
	///> to the root.	
	void GetUpdatedItems( ItemVector& aRemoved,  ItemVector& aAdded);

	///> Copies the changes from a given branch (aNode) to the root. Called on 
	///> a non-root branch will fail.
	void Commit (PNS_NODE *aNode);

	///> finds a joint at a given position, layer and nets
	const OptJoint FindJoint(const VECTOR2I &aPos, int aLayer, int aNet);

	///> finds all linest between a pair of joints. Used by the loop removal engine.
	int FindLinesBetweenJoints( PNS_JOINT& a, PNS_JOINT& b, std::vector<PNS_LINE *> &aLines );

	///> finds the joints corresponding to the ends of line aLine
	void FindLineEnds (PNS_LINE *aLine, PNS_JOINT& a, PNS_JOINT& b );

	///> finds all joints that have an (in)direct connection(s) (i.e. segments/vias) with the joint aJoint.
	void FindConnectedJoints( const PNS_JOINT& aJoint, std::vector<PNS_JOINT *> &aConnectedJoints );

	///> Destroys all child nodes. Applicable only to the root node.
	void KillChildren();

	void AllItemsInNet ( int aNet, std::list<PNS_ITEM *>& aItems);

private:

	struct obstacleVisitor;
	typedef boost::unordered_multimap<PNS_JOINT::HashTag, PNS_JOINT> JointMap;	
	typedef JointMap::value_type TagJointPair;

	/// nodes are not copyable
	PNS_NODE( const PNS_NODE& b);
	PNS_NODE &operator=(const PNS_NODE& b);
	
	///> tries to find matching joint and creates a new one if not found
	PNS_JOINT& touchJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet );
	
	///> touches a joint and links it to an item
	void linkJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet, PNS_ITEM *aWhere );

	///> unlinks an item from a joint
	void unlinkJoint( const VECTOR2I& aPos, const PNS_LAYERSET& aLayers, int aNet, PNS_ITEM *aWhere );
	
		///> helpers for adding/removing items

	void addSolid( PNS_SOLID *aSeg );
	void addSegment( PNS_SEGMENT *aSeg );
	void addLine( PNS_LINE *aLine );
	void addVia( PNS_VIA *aVia );
	void removeSolid( PNS_SOLID *aSeg );
	void removeLine( PNS_LINE *aLine );
	void removeSegment (PNS_SEGMENT *aSeg );
	void removeVia (PNS_VIA *aVia );

	void doRemove( PNS_ITEM *aItem );
	void unlinkParent ( );
	void releaseChildren ();
	
	bool isRoot() const 
	{
		return m_parent == NULL;
	}

	///> checks if this branch contains an updated version of the item from the root branch.
	bool overrides ( PNS_ITEM * aItem ) const 
	{
		return m_override.find(aItem) != m_override.end();
	}

	///> scans the joint map, forming a line starting from segment (current). 
	void followLine(PNS_SEGMENT *current, bool scanDirection, int& pos, int limit, VECTOR2I *corners, PNS_SEGMENT **segments);

	///> spatial index of all items
	//SHAPE_INDEX_LIST<PNS_ITEM *> m_items;
	
	///> hash table with the joints, linking the items. Joints are hashed by their
	///> position, layer set and net. 
	JointMap m_joints;

	///> node this node was branched from
	PNS_NODE *m_parent;

	///> root node of the whole hierarchy
	PNS_NODE *m_root;
	
	///> list of nodes branched from this one
	std::vector<PNS_NODE *> m_children;

	///> hash of root's items that are more recent in this node
	boost::unordered_set<PNS_ITEM *> m_override;

	///> worst case item-item clearance 
	int m_maxClearance;
	
	///> Clearance resolution functor
	PNS_CLEARANCE_FUNC *m_clearanceFunctor;

	///> Geometric/Net index of the items
	PNS_INDEX *m_index;

	///> list of currently processed obstacles.
	Obstacles m_obstacleList;
};

#endif