/*
 * KiRouter - a push-and-(sometimes-)shove PCB router
 *
 * Copyright (C) 2013  CERN
 * Copyright (C) 2016-2021 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 <functional>
using namespace std::placeholders;

#include <pcb_painter.h>
#include <pcbnew_settings.h>

#include <tools/pcb_grid_helper.h>
#include <wx/log.h>

#include "pns_kicad_iface.h"
#include "pns_tool_base.h"
#include "pns_arc.h"
#include "pns_solid.h"


using namespace KIGFX;

namespace PNS {


TOOL_BASE::TOOL_BASE( const std::string& aToolName ) :
    PCB_TOOL_BASE( aToolName )
{
    m_gridHelper = nullptr;
    m_iface = nullptr;
    m_router = nullptr;
    m_cancelled = false;

    m_startItem = nullptr;
    m_startHighlight = false;

    m_endItem = nullptr;
    m_gridHelper = nullptr;

    m_cancelled = false;
}


TOOL_BASE::~TOOL_BASE()
{
    delete m_gridHelper;
    delete m_iface;
    delete m_router;
}


void TOOL_BASE::Reset( RESET_REASON aReason )
{
    delete m_gridHelper;
    delete m_iface;
    delete m_router;

    m_iface = new PNS_KICAD_IFACE;
    m_iface->SetBoard( board() );
    m_iface->SetView( getView() );
    m_iface->SetHostTool( this );

    m_router = new ROUTER;
    m_router->SetInterface( m_iface );
    m_router->ClearWorld();
    m_router->SyncWorld();

    m_router->UpdateSizes( m_savedSizes );

    PCBNEW_SETTINGS* settings = frame()->GetPcbNewSettings();

    if( !settings->m_PnsSettings )
        settings->m_PnsSettings = std::make_unique<ROUTING_SETTINGS>( settings, "tools.pns" );

    m_router->LoadSettings( settings->m_PnsSettings.get() );

    m_gridHelper = new PCB_GRID_HELPER( m_toolMgr, frame()->GetMagneticItemsSettings() );
}


ITEM* TOOL_BASE::pickSingleItem( const VECTOR2I& aWhere, int aNet, int aLayer, bool aIgnorePads,
								 const std::vector<ITEM*> aAvoidItems )
{
    int tl = aLayer > 0 ? aLayer : getView()->GetTopLayer();

    static const int candidateCount = 5;
    ITEM* prioritized[candidateCount];
    SEG::ecoord dist[candidateCount];

    for( int i = 0; i < candidateCount; i++ )
    {
        prioritized[i] = nullptr;
        dist[i] = VECTOR2I::ECOORD_MAX;
    }

    ITEM_SET candidates = m_router->QueryHoverItems( aWhere );

    if( candidates.Empty() )
        candidates = m_router->QueryHoverItems( aWhere, true );

    for( ITEM* item : candidates.Items() )
    {
        if( !item->IsRoutable() )
            continue;

        if( !IsCopperLayer( item->Layers().Start() ) )
            continue;

        if( !m_iface->IsAnyLayerVisible( item->Layers() ) )
            continue;

        if( alg::contains( aAvoidItems, item ) )
            continue;

        // fixme: this causes flicker with live loop removal...
        //if( item->Parent() && !item->Parent()->ViewIsVisible() )
        //    continue;

        if( item->OfKind( ITEM::SOLID_T ) && aIgnorePads )
        {
            continue;
        }
        else if( aNet <= 0 || item->Net() == aNet )
        {
            if( item->OfKind( ITEM::VIA_T | ITEM::SOLID_T ) )
            {
                SEG::ecoord d = ( item->Shape()->Centre() - aWhere ).SquaredEuclideanNorm();

                if( d < dist[2] )
                {
                    prioritized[2] = item;
                    dist[2] = d;
                }

                if( item->Layers().Overlaps( tl ) && d < dist[0] )
                {
                    prioritized[0] = item;
                    dist[0] = d;
                }
            }
            else    // ITEM::SEGMENT_T | ITEM::ARC_T
            {
                LINKED_ITEM* li = static_cast<LINKED_ITEM*>( item );
                SEG::ecoord  d = std::min( ( li->Anchor( 0 ) - aWhere ).SquaredEuclideanNorm(),
                                           ( li->Anchor( 1 ) - aWhere ).SquaredEuclideanNorm() );

                if( d < dist[3] )
                {
                    prioritized[3] = item;
                    dist[3] = d;
                }

                if( item->Layers().Overlaps( tl ) && d < dist[1] )
                {
                    prioritized[1] = item;
                    dist[1] = d;
                }
            }
        }
        else if( item->OfKind( ITEM::SOLID_T ) && item->IsFreePad() )
        {
            // Allow free pads only when already inside pad
            if( item->Shape()->Collide( aWhere ) )
            {
                prioritized[0] = item;
                dist[0] = 0;
            }
        }
        else if ( item->Net() == 0 && m_router->Settings().Mode() == RM_MarkObstacles )
        {
            // Allow unconnected items as last resort in RM_MarkObstacles mode
            if( item->Layers().Overlaps( tl ) )
                prioritized[4] = item;
        }
    }

    ITEM* rv = nullptr;

    bool highContrast = ( frame()->GetDisplayOptions().m_ContrastModeDisplay != HIGH_CONTRAST_MODE::NORMAL );

    for( int i = 0; i < candidateCount; i++ )
    {
        ITEM* item = prioritized[i];

        if( highContrast && item && !item->Layers().Overlaps( tl ) )
            item = nullptr;

        if( item && ( aLayer < 0 || item->Layers().Overlaps( aLayer ) ) )
        {
            rv = item;
            break;
        }
    }

    if( rv )
    {
        wxLogTrace( wxT( "PNS" ), wxT( "%s, layer : %d, tl: %d" ),
                    rv->KindStr().c_str(),
                    rv->Layers().Start(),
                    tl );
    }

    return rv;
}


void TOOL_BASE::highlightNet( bool aEnabled, int aNetcode )
{
    RENDER_SETTINGS* rs = getView()->GetPainter()->GetSettings();

    if( aNetcode >= 0 && aEnabled )
    {
        // If the user has previously set the current net to be highlighted,
        // we assume they want to keep it highlighted after routing
        m_startHighlight = ( rs->IsHighlightEnabled()
                                && rs->GetHighlightNetCodes().count( aNetcode ) );

        rs->SetHighlight( true, aNetcode );
    }
    else
    {
        if( !m_startHighlight )
            rs->SetHighlight( false );

        m_startHighlight = false;
    }

    // Do not remove this call.  This is required to update the layers when we highlight a net.
    // In this case, highlighting a net dims all other elements, so the colors need to update
    getView()->UpdateAllLayersColor();
}


bool TOOL_BASE::checkSnap( ITEM *aItem )
{
    // Sync PNS engine settings with the general PCB editor options.
    auto& pnss = m_router->Settings();

    // If we're dragging a track segment, don't try to snap to items on the same copper layer.
    // This way we avoid 'flickery' behaviour for short segments when the snap algo is trying to
    // snap to the corners of the segments next to the one being dragged.
    if( m_startItem && aItem && m_router->GetState() == ROUTER::DRAG_SEGMENT
        && aItem->Layer() == m_startItem->Layer() && aItem->OfKind( ITEM::SEGMENT_T )
        && m_startItem->OfKind( ITEM::SEGMENT_T ) )
        return false;

    pnss.SetSnapToPads(
            frame()->GetMagneticItemsSettings()->pads == MAGNETIC_OPTIONS::CAPTURE_CURSOR_IN_TRACK_TOOL ||
            frame()->GetMagneticItemsSettings()->pads == MAGNETIC_OPTIONS::CAPTURE_ALWAYS );

    pnss.SetSnapToTracks(
            frame()->GetMagneticItemsSettings()->tracks == MAGNETIC_OPTIONS::CAPTURE_CURSOR_IN_TRACK_TOOL
            || frame()->GetMagneticItemsSettings()->tracks == MAGNETIC_OPTIONS::CAPTURE_ALWAYS );

    if( aItem )
    {
        if( aItem->OfKind( ITEM::VIA_T | ITEM::SEGMENT_T | ITEM::ARC_T )  )
            return pnss.GetSnapToTracks();
        else if( aItem->OfKind( ITEM::SOLID_T ) )
            return pnss.GetSnapToPads();
    }

    return false;
}


void TOOL_BASE::updateStartItem( const TOOL_EVENT& aEvent, bool aIgnorePads )
{
    int      tl = getView()->GetTopLayer();
    VECTOR2I cp = aEvent.IsPrime() ? aEvent.Position()
                                   : controls()->GetCursorPosition( !aEvent.Modifier( MD_SHIFT ) );
    VECTOR2I p;
    GAL*     gal = m_toolMgr->GetView()->GetGAL();

    controls()->ForceCursorPosition( false );
    m_gridHelper->SetUseGrid( gal->GetGridSnapping() && !aEvent.DisableGridSnapping()  );
    m_gridHelper->SetSnap( !aEvent.Modifier( MD_SHIFT ) );

    if( aEvent.IsMotion() || aEvent.IsClick() )
        p = aEvent.Position();
    else
        p = cp;

    m_startItem = pickSingleItem( aEvent.IsClick() ? cp : p, -1, -1, aIgnorePads );

    if( !m_gridHelper->GetUseGrid() && m_startItem && !m_startItem->Layers().Overlaps( tl ) )
        m_startItem = nullptr;

    m_startSnapPoint = snapToItem( m_startItem, p );
    controls()->ForceCursorPosition( true, m_startSnapPoint );
}


void TOOL_BASE::updateEndItem( const TOOL_EVENT& aEvent )
{
    int  layer;
    GAL* gal = m_toolMgr->GetView()->GetGAL();

    m_gridHelper->SetUseGrid( gal->GetGridSnapping() && !aEvent.DisableGridSnapping()  );
    m_gridHelper->SetSnap( !aEvent.Modifier( MD_SHIFT ) );

    controls()->ForceCursorPosition( false );
    
    VECTOR2I mousePos = controls()->GetMousePosition();
    
    if( m_router->GetState() == ROUTER::ROUTE_TRACK && aEvent.IsDrag() )
    {
        // If the user is moving the mouse quickly while routing then clicks will come in as
        // short drags.  In this case we want to use the drag origin rather than the current
        // mouse position.
        mousePos = aEvent.DragOrigin();
    }

    if( m_router->Settings().Mode() != RM_MarkObstacles &&
        ( m_router->GetCurrentNets().empty() || m_router->GetCurrentNets().front() < 0 ) )
    {
        m_endSnapPoint = snapToItem( nullptr, mousePos );
        controls()->ForceCursorPosition( true, m_endSnapPoint );
        m_endItem = nullptr;

        return;
    }

    if( m_router->IsPlacingVia() )
        layer = -1;
    else
        layer = m_router->GetCurrentLayer();

    ITEM* endItem = nullptr;

    std::vector<int> nets = m_router->GetCurrentNets();

    for( int net : nets )
    {
        endItem = pickSingleItem( mousePos, net, layer, false, { m_startItem } );

        if( endItem )
            break;
    }

    if( m_gridHelper->GetSnap() && checkSnap( endItem ) )
    {
        m_endItem = endItem;
        m_endSnapPoint = snapToItem( endItem, mousePos );
    }
    else
    {
        m_endItem = nullptr;
        m_endSnapPoint = m_gridHelper->Align( mousePos );
    }

    controls()->ForceCursorPosition( true, m_endSnapPoint );

    if( m_endItem )
    {
        wxLogTrace( wxT( "PNS" ), wxT( "%s, layer : %d" ),
                    m_endItem->KindStr().c_str(),
                    m_endItem->Layers().Start() );
    }
}


ROUTER *TOOL_BASE::Router() const
{
    return m_router;
}


const VECTOR2I TOOL_BASE::snapToItem( ITEM* aItem, const VECTOR2I& aP )
{
    if( !aItem || !m_iface->IsItemVisible( aItem ) )
    {
        return m_gridHelper->Align( aP );
    }

    switch( aItem->Kind() )
    {
    case ITEM::SOLID_T:
        return static_cast<SOLID*>( aItem )->Pos();

    case ITEM::VIA_T:
        return static_cast<VIA*>( aItem )->Pos();

    case ITEM::SEGMENT_T:
    case ITEM::ARC_T:
    {
        LINKED_ITEM* li = static_cast<LINKED_ITEM*>( aItem );
        VECTOR2I     A = li->Anchor( 0 );
        VECTOR2I     B = li->Anchor( 1 );
        SEG::ecoord  w_sq = SEG::Square( li->Width() / 2 );
        SEG::ecoord  distA_sq = ( aP - A ).SquaredEuclideanNorm();
        SEG::ecoord  distB_sq = ( aP - B ).SquaredEuclideanNorm();

        if( distA_sq < w_sq || distB_sq < w_sq )
        {
            return ( distA_sq < distB_sq ) ? A : B;
        }
        else if( aItem->Kind() == ITEM::SEGMENT_T )
        {
            // TODO(snh): Clean this up
            SEGMENT* seg = static_cast<SEGMENT*>( li );
            return m_gridHelper->AlignToSegment( aP, seg->Seg() );
        }
        else if( aItem->Kind() == ITEM::ARC_T )
        {
            ARC* arc = static_cast<ARC*>( li );
            return m_gridHelper->AlignToArc( aP, *static_cast<const SHAPE_ARC*>( arc->Shape() ) );
        }

        break;
    }

    default:
        break;
    }

    return m_gridHelper->Align( aP );
}

}