/*
 * 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::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);

    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.ClearSegmentLinks();

        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;
}


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

    ITEM_SET fanout = findViaFanoutByHandle( aNode, aHandle );

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

            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 ) );
        }
    }
}


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

    ITEM_SET fanout = findViaFanoutByHandle( aNode, aHandle );

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

            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 ) );
        }
    }
}


void DRAGGER::optimizeAndUpdateDraggedLine( LINE& dragged, const VECTOR2I& aP )
{
    VECTOR2D lockV;
    dragged.ClearSegmentLinks();
    dragged.Unmark();

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

    if( Settings().GetOptimizeDraggedTrack() )
    {
        OPTIMIZER::Optimize( &dragged,
                OPTIMIZER::MERGE_SEGMENTS | OPTIMIZER::KEEP_TOPOLOGY | OPTIMIZER::PRESERVE_VERTEX,
                m_lastNode, lockV );
    }

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


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 origLine( m_draggedLine );
        
        if( m_mode == DM_SEGMENT )
            dragged.DragSegment( aP, m_draggedSegmentIndex, false );
        else
            dragged.DragCorner( aP, m_draggedSegmentIndex, thresh );

        if ( m_world->CheckColliding( &dragged ) )
        {
            WALKAROUND walkaround( m_lastNode, Router() );

            walkaround.SetSolidsOnly( false );
            walkaround.SetDebugDecorator( Dbg() );
            walkaround.SetLogger( Logger() );
            walkaround.SetIterationLimit( Settings().WalkaroundIterationLimit() );

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

            //Dbg()->AddLine( wr.lineCw.CLine(), 3, 200000 );
            //Dbg()->AddLine( wr.lineCcw.CLine(), 2, 200000 );

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

        }
        else
        {
            ok = true;
        }

        if(ok)
        {
            m_lastNode->Remove( origLine );
            optimizeAndUpdateDraggedLine( dragged, aP );
        }
    break;
    }
    case DM_VIA: // fixme...
    {
        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.ClearSegmentLinks();
            dragged.Unmark();

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

            if( Settings().GetOptimizeDraggedTrack() )
            {
                OPTIMIZER::Optimize( &dragged, OPTIMIZER::MERGE_SEGMENTS 
                                            | OPTIMIZER::KEEP_TOPOLOGY
                                            | OPTIMIZER::PRESERVE_VERTEX, m_lastNode, lockV );
            }

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

        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 )
    {
        // Collisions still prevent fixing unless "Allow DRC violations" is checked
        if( !m_dragStatus )
            return false;

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

    return false;
}


bool DRAGGER::Drag( const VECTOR2I& aP )
{
    if( m_freeAngleMode )
        return dragMarkObstacles( aP );

    switch( m_currentMode )
    {
    case RM_MarkObstacles:
        return dragMarkObstacles( aP );

    case RM_Shove:
    case RM_Smart:
        return dragShove( aP );

    case RM_Walkaround:
        return dragWalkaround( aP );

    default:
        return false;
    }
}


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


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

}