/*
 * KiRouter - a push-and-(sometimes-)shove PCB router
 *
 * Copyright (C) 2013-2014 CERN
 * Copyright (C) 2016-2019 KiCad Developers, see AUTHORS.txt for contributors.
 * 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.org/licenses/>.
 */

#include "pns_arc.h"

#include "pns_dragger.h"
#include "pns_shove.h"
#include "pns_router.h"
#include "pns_debug_decorator.h"
#include "pns_walkaround.h"

namespace PNS {

DRAGGER::DRAGGER( ROUTER* aRouter ) :
    DRAG_ALGO( aRouter )
{
    m_world = NULL;
    m_lastNode = NULL;
    m_mode = DM_SEGMENT;
    m_draggedSegmentIndex = 0;
    m_dragStatus = false;
    m_currentMode = RM_MarkObstacles;
    m_freeAngleMode = false;
}


DRAGGER::~DRAGGER()
{
}


bool DRAGGER::propagateViaForces( NODE* node, std::set<VIA*>& vias )
{
    VIA* via = *vias.begin();

    VECTOR2I force;
    VECTOR2I lead = m_mouseTrailTracer.GetTrailLeadVector();

    bool solidsOnly = false;// ( m_currentMode != RM_Walkaround );

    if( via->PushoutForce( node, lead, force, solidsOnly, 40 ) )
    {
        via->SetPos( via->Pos() + force );
        return true;
    }

    return false;
}

bool DRAGGER::startDragSegment( const VECTOR2D& aP, SEGMENT* aSeg )
{
    int w2 = aSeg->Width() / 2;

    m_draggedLine = m_world->AssembleLine( aSeg, &m_draggedSegmentIndex );

    if( m_shove )
    {
        m_shove->SetInitialLine( m_draggedLine );
    }

    auto distA = ( aP - aSeg->Seg().A ).EuclideanNorm();
    auto distB = ( aP - aSeg->Seg().B ).EuclideanNorm();

    if( distA <= w2 )
    {
        m_mode = DM_CORNER;
    }
    else if( distB <= w2 )
    {
        //todo (snh) Adjust segment for arcs
        m_draggedSegmentIndex++;
        m_mode = DM_CORNER;
    }
    else if ( m_freeAngleMode )
    {
        if( distB < distA )
        {
            m_draggedSegmentIndex++;
        }
        m_mode = DM_CORNER;
    }
    else
    {
        m_mode = DM_SEGMENT;
    }

    return true;
}



bool DRAGGER::startDragArc( const VECTOR2D& aP, ARC* aArc )
{
    m_draggedLine = m_world->AssembleLine( aArc, &m_draggedSegmentIndex );
    m_shove->SetInitialLine( m_draggedLine );
    m_mode = DM_ARC;

    return true;
}


bool DRAGGER::startDragVia( VIA* aVia )
{
    m_initialVia = aVia->MakeHandle();
    m_draggedVia = m_initialVia;

    m_mode = DM_VIA;

    return true;
}

const ITEM_SET DRAGGER::findViaFanoutByHandle ( NODE *aNode, const VIA_HANDLE& handle )
{
    ITEM_SET rv;

    JOINT* jt = aNode->FindJoint( handle.pos, handle.layers.Start(), handle.net );

    if( !jt )
        return rv;

    for( ITEM* item : jt->LinkList() )
    {
        if( item->OfKind( ITEM::SEGMENT_T | ITEM::ARC_T ) )
        {
            int segIndex;
            LINKED_ITEM* seg = ( LINKED_ITEM*) item;
            LINE l = aNode->AssembleLine( seg, &segIndex );

            if( segIndex != 0 )
                l.Reverse();

            rv.Add( l );
        }
        else if( item->OfKind( ITEM::VIA_T ) )
        {
            rv.Add( item );
        }
    }

    return rv;
}

bool DRAGGER::Start( const VECTOR2I& aP, ITEM_SET& aPrimitives )
{
    if( aPrimitives.Empty() )
        return false;

    ITEM* startItem = aPrimitives[0];

    m_lastNode = NULL;
    m_draggedItems.Clear();
    m_currentMode = Settings().Mode();
    m_freeAngleMode = (m_mode & DM_FREE_ANGLE);
    m_lastValidPoint = aP;

    m_mouseTrailTracer.Clear();
    m_mouseTrailTracer.AddTrailPoint( aP );

    if( m_currentMode == RM_Shove  && !m_freeAngleMode )
    {
        m_shove = std::make_unique<SHOVE>( m_world, Router() );
        m_shove->SetLogger( Logger() );
        m_shove->SetDebugDecorator( Dbg() );
    }

    startItem->Unmark( MK_LOCKED );

    wxLogTrace( "PNS", "StartDragging: item %p [kind %d]", startItem, (int) startItem->Kind() );

    switch( startItem->Kind() )
    {
    case ITEM::SEGMENT_T:
        return startDragSegment( aP, static_cast<SEGMENT*>( startItem ) );

    case ITEM::VIA_T:
        return startDragVia( static_cast<VIA*>( startItem ) );

    case ITEM::ARC_T:
        return startDragArc( aP, static_cast<ARC*>( startItem ) );

    default:
        return false;
    }
}


void DRAGGER::SetMode( int aMode )
{
    m_mode = aMode;
}


bool DRAGGER::dragMarkObstacles( const VECTOR2I& aP )
{
    // fixme: rewrite using shared_ptr...
    if( m_lastNode )
    {
        delete m_lastNode;
        m_lastNode = nullptr;
    }

    m_lastNode = m_world->Branch();

    switch( m_mode )
    {
    case DM_SEGMENT:
    case DM_CORNER:
    {
        //TODO: Make threshhold configurable
        int  thresh = Settings().SmoothDraggedSegments() ? m_draggedLine.Width() / 4 : 0;
        LINE origLine( m_draggedLine );
        LINE dragged( m_draggedLine );
        dragged.SetSnapThreshhold( thresh );
        dragged.ClearLinks();

        if( m_mode == DM_SEGMENT )
            dragged.DragSegment( aP, m_draggedSegmentIndex );
        else
            dragged.DragCorner( aP, m_draggedSegmentIndex, m_freeAngleMode );

        m_lastNode->Remove( origLine );
        m_lastNode->Add( dragged );

        m_draggedItems.Clear();
        m_draggedItems.Add( dragged );

        break;
    }

    case DM_VIA: // fixme...
    {
        dragViaMarkObstacles( m_initialVia, m_lastNode, aP );

        break;
    }
    }

    if( Settings().CanViolateDRC() )
        m_dragStatus = true;
    else
        m_dragStatus = !m_world->CheckColliding( m_draggedItems );

    return true;
}


bool DRAGGER::dragViaMarkObstacles( const VIA_HANDLE& aHandle, NODE* aNode, const VECTOR2I& aP )
{
    m_draggedItems.Clear();

    ITEM_SET fanout = findViaFanoutByHandle( aNode, aHandle );

    if( fanout.Empty() )
    {
        return true;
    }
    
    for( ITEM* item : fanout.Items() )
    {
        if( const LINE* l = dyn_cast<const LINE*>( item ) )
        {
            LINE origLine( *l );
            LINE draggedLine( *l );

            draggedLine.DragCorner( aP, origLine.CLine().Find( aHandle.pos ), m_freeAngleMode );
            draggedLine.ClearLinks();

            m_draggedItems.Add( draggedLine );

            m_lastNode->Remove( origLine );
            m_lastNode->Add( draggedLine );
        }
        else if ( VIA *via = dyn_cast<VIA*>( item ) )
        {
            auto nvia = Clone( *via );

            nvia->SetPos( aP );
            m_draggedItems.Add( nvia.get() );

            m_lastNode->Remove( via );
            m_lastNode->Add( std::move( nvia ) );
        }
    }

    return true;
}


bool DRAGGER::dragViaWalkaround( const VIA_HANDLE& aHandle, NODE* aNode, const VECTOR2I& aP )
{
    m_draggedItems.Clear();

    ITEM_SET fanout = findViaFanoutByHandle( aNode, aHandle );

    if( fanout.Empty() )
    {
        return true;
    }

    bool viaPropOk = false;
    VECTOR2I viaTargetPos;

    for( ITEM* item : fanout.Items() )
    {
        if ( VIA *via = dyn_cast<VIA*>( item ) )
        {
            auto draggedVia = Clone( *via );

            draggedVia->SetPos( aP );
            m_draggedItems.Add( draggedVia.get() );

            std::set<VIA*> vias;

            vias.insert( draggedVia.get() );

            bool ok = propagateViaForces( m_lastNode, vias );

            if( ok )
            {
                viaTargetPos = draggedVia->Pos();
                viaPropOk = true;
                m_lastNode->Remove( via );
                m_lastNode->Add( std::move(draggedVia) );
            }
        }
    }

    if( !viaPropOk ) // can't force-propagate the via? bummer...
        return false;
    
    for( ITEM* item : fanout.Items() )
    {
        if( const LINE* l = dyn_cast<const LINE*>( item ) )
        {
            LINE origLine( *l );
            LINE draggedLine( *l );
            LINE walkLine( *l );

            draggedLine.DragCorner( viaTargetPos, origLine.CLine().Find( aHandle.pos ), m_freeAngleMode );
            draggedLine.ClearLinks();

            if ( m_world->CheckColliding( &draggedLine ) )
            {
                bool ok = tryWalkaround( m_lastNode, draggedLine, walkLine );
        
                if( !ok )
                    return false;

            m_lastNode->Remove( origLine );
                optimizeAndUpdateDraggedLine( walkLine, origLine, aP );
        }
            else
        {
                m_draggedItems.Add( draggedLine );

                m_lastNode->Remove( origLine );
                m_lastNode->Add( draggedLine );
        }
    }
}

    return true;
}


void DRAGGER::optimizeAndUpdateDraggedLine( LINE& aDragged, const LINE& aOrig, const VECTOR2I& aP )
{
    VECTOR2D lockV;
    aDragged.ClearLinks();
    aDragged.Unmark();

    lockV = aDragged.CLine().NearestPoint( aP );

    if( Settings().GetOptimizeDraggedTrack() )
    {
        OPTIMIZER optimizer( m_lastNode );

        optimizer.SetEffortLevel( OPTIMIZER::MERGE_SEGMENTS | OPTIMIZER::KEEP_TOPOLOGY );


        OPT_BOX2I affectedArea = *aDragged.ChangedArea( &aOrig );

        optimizer.SetPreserveVertex( aP );

        if( affectedArea )
        {
            //Dbg()->AddBox( *affectedArea, 2 );
            optimizer.SetRestrictArea( *affectedArea );
            optimizer.Optimize( &aDragged );
	}
        

            OPT_BOX2I optArea = *aDragged.ChangedArea( &aOrig );
            if( optArea )
                Dbg()->AddBox( *optArea, 4 );


        }
    }

    m_lastNode->Add( aDragged );
    m_draggedItems.Clear();
    m_draggedItems.Add( aDragged );
}


bool DRAGGER::tryWalkaround( NODE* aNode, LINE& aOrig, LINE& aWalk )
{
    WALKAROUND walkaround( aNode, Router() );
    bool       ok = false;
    walkaround.SetSolidsOnly( false );
    walkaround.SetDebugDecorator( Dbg() );
    walkaround.SetLogger( Logger() );
    walkaround.SetIterationLimit( Settings().WalkaroundIterationLimit() );

    aWalk = aOrig;

    WALKAROUND::RESULT wr = walkaround.Route( aWalk );


    if( wr.statusCcw == WALKAROUND::DONE && wr.statusCw == WALKAROUND::DONE )
    {
        aWalk = ( wr.lineCw.CLine().Length() < wr.lineCcw.CLine().Length() ? wr.lineCw :
                                                                             wr.lineCcw );
        ok    = true;
    }
    else if( wr.statusCw == WALKAROUND::DONE )
    {
        aWalk = wr.lineCw;
        ok    = true;
    }
    else if( wr.statusCcw == WALKAROUND::DONE )
    {
        aWalk = wr.lineCcw;
        ok    = true;
    }
    return ok;
}


bool DRAGGER::dragWalkaround( const VECTOR2I& aP )
{
    bool ok = false;
// fixme: rewrite using shared_ptr...
    if( m_lastNode )
    {
        delete m_lastNode;
        m_lastNode = nullptr;
    }

    m_lastNode = m_world->Branch();

    switch( m_mode )
    {
    case DM_SEGMENT:
    case DM_CORNER:
    {
        int thresh = Settings().SmoothDraggedSegments() ? m_draggedLine.Width() / 4 : 0;
        LINE dragged( m_draggedLine );
        LINE draggedWalk( m_draggedLine );
        LINE origLine( m_draggedLine );
        
        dragged.SetSnapThreshhold( thresh );

        if( m_mode == DM_SEGMENT )
            dragged.DragSegment( aP, m_draggedSegmentIndex );
        else
            dragged.DragCorner( aP, m_draggedSegmentIndex );

        if ( m_world->CheckColliding( &dragged ) )
        {
            ok = tryWalkaround( m_lastNode, dragged, draggedWalk );
        }
        else
        {
            draggedWalk = dragged;
            ok = true;
        }

        if( ok )
        {
            m_lastNode->Remove( origLine );
            optimizeAndUpdateDraggedLine( draggedWalk, origLine, aP );
        }
    break;
    }
    case DM_VIA: // fixme...
    {
        ok = dragViaWalkaround( m_initialVia, m_lastNode, aP );
        break;
    }
    }

    m_dragStatus = ok;

    return true;
}

bool DRAGGER::dragShove( const VECTOR2I& aP )
{
    bool ok = false;

    if( m_lastNode )
    {
        delete m_lastNode;
        m_lastNode = NULL;
    }

    switch( m_mode )
    {
    case DM_SEGMENT:
    case DM_CORNER:
    {
        //TODO: Make threshhold configurable
        int  thresh = Settings().SmoothDraggedSegments() ? m_draggedLine.Width() / 2 : 0;
        LINE dragged( m_draggedLine );
        dragged.SetSnapThreshhold( thresh );

        if( m_mode == DM_SEGMENT )
            dragged.DragSegment( aP, m_draggedSegmentIndex );
        else
            dragged.DragCorner( aP, m_draggedSegmentIndex );

        SHOVE::SHOVE_STATUS st = m_shove->ShoveLines( dragged );

        if( st == SHOVE::SH_OK )
            ok = true;
        else if( st == SHOVE::SH_HEAD_MODIFIED )
        {
            dragged = m_shove->NewHead();
            ok = true;
        }

        m_lastNode = m_shove->CurrentNode()->Branch();

        if( ok )
        {
            VECTOR2D lockV;
            dragged.ClearLinks();
            dragged.Unmark();

            optimizeAndUpdateDraggedLine( dragged, m_draggedLine, aP );
        }

        break;
    }

    case DM_VIA:
    {
        VIA_HANDLE newVia;

        SHOVE::SHOVE_STATUS st = m_shove->ShoveDraggingVia( m_draggedVia, aP, newVia );

        if( st == SHOVE::SH_OK || st == SHOVE::SH_HEAD_MODIFIED )
            ok = true;

        m_lastNode = m_shove->CurrentNode()->Branch();

        if( newVia.valid )
            m_draggedVia = newVia;

        m_draggedItems.Clear();
        break;
    }
    }

    m_dragStatus = ok;

    return ok;
}


bool DRAGGER::FixRoute()
{
    NODE* node = CurrentNode();

    if( node )
    {
        // If collisions exist, we can fix in shove/smart mode because all tracks to be committed
        // will be in valid positions (even if the current routing solution to the mouse cursor is
        // invalid).  In other modes, we can only commit if "Allow DRC violations" is enabled.
        if( !m_dragStatus )
        {
            Drag( m_lastValidPoint );
            node = CurrentNode();

            if( !node )
                return false;
        }

        if( !m_dragStatus && !Settings().CanViolateDRC()  )
            return false;

        Router()->CommitRouting( node );
        return true;
    }

    return false;
}


bool DRAGGER::Drag( const VECTOR2I& aP )
{
    m_mouseTrailTracer.AddTrailPoint( aP );

    bool ret = false;

    if( m_freeAngleMode )
    {
        ret = dragMarkObstacles( aP );
    }
    else
    {
        switch( m_currentMode )
        {
        case RM_MarkObstacles:
            ret = dragMarkObstacles( aP );
            break;

        case RM_Shove:
        case RM_Smart:
            ret = dragShove( aP );
            break;

        case RM_Walkaround:
            ret = dragWalkaround( aP );
            break;

        default:
            break;
        }
    }

    if( ret )
        m_lastValidPoint = aP;

    return ret;
}


NODE* DRAGGER::CurrentNode() const
{
   return m_lastNode ? m_lastNode : m_world;
}


const ITEM_SET DRAGGER::Traces()
{
    return m_draggedItems;
}

}