void QgsGeometryDuplicateNodesCheck::collectErrors( const QMap<QString, QgsFeaturePool *> &featurePools, QList<QgsGeometryCheckError *> &errors, QStringList &messages, QgsFeedback *feedback, const LayerFeatureIds &ids ) const
{
  Q_UNUSED( messages )

  QMap<QString, QgsFeatureIds> featureIds = ids.isEmpty() ? allLayerFeatureIds( featurePools ) : ids.toMap();
  QgsGeometryCheckerUtils::LayerFeatures layerFeatures( featurePools, featureIds, compatibleGeometryTypes(), feedback, mContext );
  for ( const QgsGeometryCheckerUtils::LayerFeature &layerFeature : layerFeatures )
  {
    const QgsAbstractGeometry *geom = layerFeature.geometry().constGet();
    for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
    {
      for ( int iRing = 0, nRings = geom->ringCount( iPart ); iRing < nRings; ++iRing )
      {
        int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, iPart, iRing );
        if ( nVerts < 2 )
          continue;
        for ( int iVert = nVerts - 1, jVert = 0; jVert < nVerts; iVert = jVert++ )
        {
          QgsPoint pi = geom->vertexAt( QgsVertexId( iPart, iRing, iVert ) );
          QgsPoint pj = geom->vertexAt( QgsVertexId( iPart, iRing, jVert ) );
          if ( QgsGeometryUtils::sqrDistance2D( pi, pj ) < mContext->tolerance )
          {
            errors.append( new QgsGeometryCheckError( this, layerFeature, pj, QgsVertexId( iPart, iRing, jVert ) ) );
          }
        }
      }
    }
  }
}

void QgsGeometryDuplicateNodesCheck::collectErrors( QList<QgsGeometryCheckError*>& errors, QStringList &/*messages*/, QAtomicInt* progressCounter , const QgsFeatureIds &ids ) const
{
  const QgsFeatureIds& featureIds = ids.isEmpty() ? mFeaturePool->getFeatureIds() : ids;
  Q_FOREACH ( QgsFeatureId featureid, featureIds )
  {
    if ( progressCounter ) progressCounter->fetchAndAddRelaxed( 1 );
    QgsFeature feature;
    if ( !mFeaturePool->get( featureid, feature ) )
    {
      continue;
    }

    QgsGeometry featureGeom = feature.geometry();
    QgsAbstractGeometry* geom = featureGeom.geometry();
    for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
    {
      for ( int iRing = 0, nRings = geom->ringCount( iPart ); iRing < nRings; ++iRing )
      {
        int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, iPart, iRing );
        if ( nVerts < 2 )
          continue;
        for ( int iVert = nVerts - 1, jVert = 0; jVert < nVerts; iVert = jVert++ )
        {
          QgsPointV2 pi = geom->vertexAt( QgsVertexId( iPart, iRing, iVert ) );
          QgsPointV2 pj = geom->vertexAt( QgsVertexId( iPart, iRing, jVert ) );
          if ( QgsGeometryUtils::sqrDistance2D( pi, pj ) < QgsGeometryCheckPrecision::tolerance() * QgsGeometryCheckPrecision::tolerance() )
          {
            errors.append( new QgsGeometryCheckError( this, featureid, pj, QgsVertexId( iPart, iRing, jVert ) ) );
          }
        }
      }
    }
  }
}

int QgsCurvePolygon::vertexNumberFromVertexId( QgsVertexId id ) const
{
  if ( id.part != 0 )
    return -1;

  if ( id.ring < 0 || id.ring >= ringCount() )
    return -1;

  int number = 0;
  if ( id.ring == 0 && mExteriorRing )
  {
    return mExteriorRing->vertexNumberFromVertexId( QgsVertexId( 0, 0, id.vertex ) );
  }
  else
  {
    number += mExteriorRing->numPoints();
  }

  for ( int i = 0; i < mInteriorRings.count(); ++i )
  {
    if ( id.ring == i + 1 )
    {
      int partNumber = mInteriorRings.at( i )->vertexNumberFromVertexId( QgsVertexId( 0, 0, id.vertex ) );
      if ( partNumber == -1 )
        return -1;
      return number + partNumber;
    }
    else
    {
      number += mInteriorRings.at( i )->numPoints();
    }
  }
  return -1; // should not happen
}

bool QgsCompoundCurve::removeDuplicateNodes( double epsilon, bool useZValues )
{
  bool result = false;
  const QVector< QgsCurve * > curves = mCurves;
  int i = 0;
  QgsPoint lastEnd;
  for ( QgsCurve *curve : curves )
  {
    result = result || curve->removeDuplicateNodes( epsilon, useZValues );
    if ( curve->numPoints() == 0 || qgsDoubleNear( curve->length(), 0.0, epsilon ) )
    {
      // empty curve, remove it
      delete mCurves.takeAt( i );
      result = true;
    }
    else
    {
      // ensure this line starts exactly where previous line ended
      if ( i > 0 )
      {
        curve->moveVertex( QgsVertexId( -1, -1, 0 ), lastEnd );
      }
      lastEnd = curve->vertexAt( QgsVertexId( -1, -1, curve->numPoints() - 1 ) );
    }
    i++;
  }
  return result;
}

void QgsTriangle::setExteriorRing( QgsCurve *ring )
{
  if ( !ring )
  {
    return;
  }

  if ( ring->hasCurvedSegments() )
  {
    //need to segmentize ring as polygon does not support curves
    QgsCurve *line = ring->segmentize();
    delete ring;
    ring = line;
  }

  if ( ( ring->numPoints() > 4 ) || ( ring->numPoints() < 3 ) )
  {
    delete ring;
    return;
  }
  else if ( ring->numPoints() == 4 )
  {
    if ( !ring->isClosed() )
    {
      delete ring;
      return;
    }
  }
  else if ( ring->numPoints() == 3 )
  {
    if ( ring->isClosed() )
    {
      delete ring;
      return;
    }
    QgsLineString *lineString = static_cast< QgsLineString *>( ring );
    if ( !lineString->isClosed() )
    {
      lineString->close();
    }
    ring = lineString;
  }

  if ( !validateGeom( ring->vertexAt( QgsVertexId( 0, 0, 0 ) ), ring->vertexAt( QgsVertexId( 0, 0, 1 ) ), ring->vertexAt( QgsVertexId( 0, 0, 2 ) ) ) )
  {
    delete ring;
    return;
  }

  mExteriorRing.reset( ring );

  //set proper wkb type
  setZMTypeFromSubGeometry( ring, QgsWkbTypes::Triangle );

  clearCache();
}

void QgsGeometryUtils::adjacentVertices( const QgsAbstractGeometryV2& geom, const QgsVertexId& atVertex, QgsVertexId& beforeVertex, QgsVertexId& afterVertex )
{
  bool polygonType = ( geom.dimension()  == 2 );
  QList< QList< QList< QgsPointV2 > > > coords;
  geom.coordinateSequence( coords );

  //get feature
  if ( coords.size() <= atVertex.part )
  {
    return; //error, no such feature
  }
  const QList< QList< QgsPointV2 > >& part = coords.at( atVertex.part );

  //get ring
  if ( part.size() <= atVertex.ring )
  {
    return; //error, no such ring
  }
  const QList< QgsPointV2 >& ring = part.at( atVertex.ring );
  if ( ring.size() <= atVertex.vertex )
  {
    return;
  }

  //vertex in the middle
  if ( atVertex.vertex > 0 && atVertex.vertex < ring.size() - 1 )
  {
    beforeVertex.part = atVertex.part; beforeVertex.ring = atVertex.ring; beforeVertex.vertex = atVertex.vertex - 1;
    afterVertex.part = atVertex.part; afterVertex.ring = atVertex.ring; afterVertex.vertex = atVertex.vertex + 1;
  }
  else if ( atVertex.vertex == 0 )
  {
    afterVertex.part = atVertex.part; afterVertex.ring = atVertex.ring; afterVertex.vertex = atVertex.vertex + 1;
    if ( polygonType && ring.size() > 3 )
    {
      beforeVertex.part = atVertex.part; beforeVertex.ring = atVertex.ring; beforeVertex.vertex = ring.size() - 2;
    }
    else
    {
      beforeVertex = QgsVertexId(); //before vertex invalid
    }
  }
  else if ( atVertex.vertex == ring.size() - 1 )
  {
    beforeVertex.part = atVertex.part; beforeVertex.ring = atVertex.ring; beforeVertex.vertex = atVertex.vertex - 1;
    if ( polygonType )
    {
      afterVertex.part = atVertex.part; afterVertex.ring = atVertex.ring; afterVertex.vertex = 1;
    }
    else
    {
      afterVertex = QgsVertexId(); //after vertex invalid
    }
  }
}

void QgsGeometryCollection::adjacentVertices( QgsVertexId vertex, QgsVertexId &previousVertex, QgsVertexId &nextVertex ) const
{
  if ( vertex.part < 0 || vertex.part >= mGeometries.count() )
  {
    previousVertex = QgsVertexId();
    nextVertex = QgsVertexId();
    return;
  }

  mGeometries.at( vertex.part )->adjacentVertices( vertex, previousVertex, nextVertex );
}

void ringAdjacentVertices( const QgsCurve *curve, QgsVertexId vertex, QgsVertexId &previousVertex, QgsVertexId &nextVertex )
{
  int n = curve->numPoints();
  if ( vertex.vertex < 0 || vertex.vertex >= n )
  {
    previousVertex = QgsVertexId();
    nextVertex = QgsVertexId();
    return;
  }

  if ( vertex.vertex == 0 && n < 3 )
  {
    previousVertex = QgsVertexId();
  }
  else if ( vertex.vertex == 0 )
  {
    previousVertex = QgsVertexId( vertex.part, vertex.ring, n - 2 );
  }
  else
  {
    previousVertex = QgsVertexId( vertex.part, vertex.ring, vertex.vertex - 1 );
  }
  if ( vertex.vertex == n - 1 && n < 3 )
  {
    nextVertex = QgsVertexId();
  }
  else if ( vertex.vertex == n - 1 )
  {
    nextVertex = QgsVertexId( vertex.part, vertex.ring, 1 );
  }
  else
  {
    nextVertex = QgsVertexId( vertex.part, vertex.ring, vertex.vertex + 1 );
  }
}

void QgsGeometryLineLayerIntersectionCheck::collectErrors( QList<QgsGeometryCheckError *> &errors, QStringList &/*messages*/, QAtomicInt *progressCounter, const QMap<QString, QgsFeatureIds> &ids ) const
{
  QMap<QString, QgsFeatureIds> featureIds = ids.isEmpty() ? allLayerFeatureIds() : ids;
  featureIds.remove( mCheckLayer ); // Don't check layer against itself
  QgsGeometryCheckerUtils::LayerFeatures layerFeatures( mContext->featurePools, featureIds, mCompatibleGeometryTypes, progressCounter, mContext, true );
  for ( const QgsGeometryCheckerUtils::LayerFeature &layerFeature : layerFeatures )
  {
    const QgsAbstractGeometry *geom = layerFeature.geometry().constGet();
    for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
    {
      const QgsLineString *line = dynamic_cast<const QgsLineString *>( QgsGeometryCheckerUtils::getGeomPart( geom, iPart ) );
      if ( !line )
      {
        // Should not happen
        continue;
      }

      // Check whether the line intersects with any other features of the specified layer
      QgsGeometryCheckerUtils::LayerFeatures checkFeatures( mContext->featurePools, QStringList() << mCheckLayer, line->boundingBox(), {QgsWkbTypes::LineGeometry, QgsWkbTypes::PolygonGeometry}, mContext );
      for ( const QgsGeometryCheckerUtils::LayerFeature &checkFeature : checkFeatures )
      {
        const QgsAbstractGeometry *testGeom = checkFeature.geometry().constGet();
        for ( int jPart = 0, mParts = testGeom->partCount(); jPart < mParts; ++jPart )
        {
          const QgsAbstractGeometry *part = QgsGeometryCheckerUtils::getGeomPart( testGeom, jPart );
          if ( const QgsLineString *testLine = dynamic_cast<const QgsLineString *>( part ) )
          {
            const QList< QgsPoint > intersections = QgsGeometryCheckerUtils::lineIntersections( line, testLine, mContext->tolerance );
            for ( const QgsPoint &inter : intersections )
            {
              errors.append( new QgsGeometryCheckError( this, layerFeature, inter, QgsVertexId( iPart ), checkFeature.id() ) );
            }
          }
          else if ( const QgsPolygon *polygon = dynamic_cast<const QgsPolygon *>( part ) )
          {
            QList< const QgsLineString * > rings = QgsGeometryCheckerUtils::polygonRings( polygon );
            for ( const QgsLineString *ring : rings )
            {
              const QList< QgsPoint > intersections = QgsGeometryCheckerUtils::lineIntersections( line, ring, mContext->tolerance );
              for ( const QgsPoint &inter : intersections )
              {
                errors.append( new QgsGeometryCheckError( this, layerFeature, inter, QgsVertexId( iPart ), checkFeature.id() ) );
              }
            }
          }
        }
      }
    }
  }
}

void QgsGeometryAngleCheck::collectErrors( QList<QgsGeometryCheckError *> &errors, QStringList &/*messages*/, QAtomicInt *progressCounter, const QgsFeatureIds &ids ) const
{
  const QgsFeatureIds &featureIds = ids.isEmpty() ? mFeaturePool->getFeatureIds() : ids;
  Q_FOREACH ( QgsFeatureId featureid, featureIds )
  {
    if ( progressCounter ) progressCounter->fetchAndAddRelaxed( 1 );
    QgsFeature feature;
    if ( !mFeaturePool->get( featureid, feature ) )
    {
      continue;
    }
    QgsGeometry g = feature.geometry();
    const QgsAbstractGeometry *geom = g.geometry();
    for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
    {
      for ( int iRing = 0, nRings = geom->ringCount( iPart ); iRing < nRings; ++iRing )
      {
        int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, iPart, iRing );
        // Less than three points, no angles to check
        if ( nVerts < 3 )
        {
          continue;
        }
        for ( int iVert = 0; iVert < nVerts; ++iVert )
        {
          const QgsPoint &p1 = geom->vertexAt( QgsVertexId( iPart, iRing, ( iVert - 1 + nVerts ) % nVerts ) );
          const QgsPoint &p2 = geom->vertexAt( QgsVertexId( iPart, iRing, iVert ) );
          const QgsPoint &p3 = geom->vertexAt( QgsVertexId( iPart, iRing, ( iVert + 1 ) % nVerts ) );
          QgsVector v21, v23;
          try
          {
            v21 = QgsVector( p1.x() - p2.x(), p1.y() - p2.y() ).normalized();
            v23 = QgsVector( p3.x() - p2.x(), p3.y() - p2.y() ).normalized();
          }
          catch ( const QgsException & )
          {
            // Zero length vectors
            continue;
          }

          double angle = std::acos( v21 * v23 ) / M_PI * 180.0;
          if ( angle < mMinAngle )
          {
            errors.append( new QgsGeometryCheckError( this, featureid, p2, QgsVertexId( iPart, iRing, iVert ), angle ) );
          }
        }
      }
    }
  }
}

void QgsGeometryCheck::deleteFeatureGeometryRing( const QString &layerId, QgsFeature &feature, int partIdx, int ringIdx, Changes &changes ) const
{
  QgsFeaturePool *featurePool = mContext->featurePools[layerId];
  QgsGeometry featureGeom = feature.geometry();
  QgsAbstractGeometry *partGeom = QgsGeometryCheckerUtils::getGeomPart( featureGeom.get(), partIdx );
  if ( dynamic_cast<QgsCurvePolygon *>( partGeom ) )
  {
    // If we delete the exterior ring of a polygon, it makes no sense to keep the interiors
    if ( ringIdx == 0 )
    {
      deleteFeatureGeometryPart( layerId, feature, partIdx, changes );
    }
    else
    {
      static_cast<QgsCurvePolygon *>( partGeom )->removeInteriorRing( ringIdx - 1 );
      feature.setGeometry( featureGeom );
      featurePool->updateFeature( feature );
      changes[layerId][feature.id()].append( Change( ChangeRing, ChangeRemoved, QgsVertexId( partIdx, ringIdx ) ) );
    }
  }
  // Other geometry types do not have rings, remove the entire part
  else
  {
    deleteFeatureGeometryPart( layerId, feature, partIdx, changes );
  }
}

void QgsGeometryCheck::deleteFeatureGeometryPart( const QString &layerId, QgsFeature &feature, int partIdx, Changes &changes ) const
{
  QgsFeaturePool *featurePool = mContext->featurePools[layerId];
  QgsGeometry featureGeom = feature.geometry();
  QgsAbstractGeometry *geom = featureGeom.get();
  if ( dynamic_cast<QgsGeometryCollection *>( geom ) )
  {
    static_cast<QgsGeometryCollection *>( geom )->removeGeometry( partIdx );
    if ( static_cast<QgsGeometryCollection *>( geom )->numGeometries() == 0 )
    {
      featurePool->deleteFeature( feature.id() );
      changes[layerId][feature.id()].append( Change( ChangeFeature, ChangeRemoved ) );
    }
    else
    {
      feature.setGeometry( featureGeom );
      featurePool->updateFeature( feature );
      changes[layerId][feature.id()].append( Change( ChangePart, ChangeRemoved, QgsVertexId( partIdx ) ) );
    }
  }
  else
  {
    featurePool->deleteFeature( feature.id() );
    changes[layerId][feature.id()].append( Change( ChangeFeature, ChangeRemoved ) );
  }
}

void QgsGeometryAreaCheck::collectErrors( QList<QgsGeometryCheckError*>& errors, QStringList &/*messages*/, QAtomicInt* progressCounter , const QgsFeatureIds &ids ) const
{
  const QgsFeatureIds& featureIds = ids.isEmpty() ? mFeaturePool->getFeatureIds() : ids;
  foreach ( const QgsFeatureId& featureid, featureIds )
  {
    if ( progressCounter ) progressCounter->fetchAndAddRelaxed( 1 );
    QgsFeature feature;
    if ( !mFeaturePool->get( featureid, feature ) )
    {
      continue;
    }

    QgsAbstractGeometryV2* geom = feature.geometry()->geometry();
    if ( dynamic_cast<QgsGeometryCollectionV2*>( geom ) )
    {
      QgsGeometryCollectionV2* multiGeom = static_cast<QgsGeometryCollectionV2*>( geom );
      for ( int i = 0, n = multiGeom->numGeometries(); i < n; ++i )
      {
        double value;
        if ( checkThreshold( multiGeom->geometryN( i ), value ) )
        {
          errors.append( new QgsGeometryCheckError( this, featureid, multiGeom->geometryN( i )->centroid(), QgsVertexId( i ), value, QgsGeometryCheckError::ValueArea ) );
        }
      }
    }
    else
    {
      double value;
      if ( checkThreshold( geom, value ) )
      {
        errors.append( new QgsGeometryCheckError( this, featureid, geom->centroid(), QgsVertexId( 0 ), value, QgsGeometryCheckError::ValueArea ) );
      }
    }
  }
}

bool QgsTriangle::moveVertex( QgsVertexId vId, const QgsPoint &newPos )
{
  if ( !mExteriorRing || vId.part != 0 || vId.ring != 0 || vId.vertex < 0 || vId.vertex > 4 )
  {
    return false;
  }

  if ( vId.vertex == 4 )
  {
    vId.vertex = 0;
  }

  QgsPoint p1( vId.vertex == 0 ? newPos : vertexAt( 0 ) );
  QgsPoint p2( vId.vertex == 1 ? newPos : vertexAt( 1 ) );
  QgsPoint p3( vId.vertex == 2 ? newPos : vertexAt( 2 ) );

  if ( !validateGeom( p1, p2, p3 ) )
  {
    return false;
  }

  int n = mExteriorRing->numPoints();
  bool success = mExteriorRing->moveVertex( vId, newPos );
  if ( success )
  {
    // If first or last vertex is moved, also move the last/first vertex
    if ( vId.vertex == 0 )
      mExteriorRing->moveVertex( QgsVertexId( vId.part, vId.ring, n - 1 ), newPos );
    clearCache();
  }
  return success;
}

double QgsLineString::closestSegment( const QgsPoint &pt, QgsPoint &segmentPt,  QgsVertexId &vertexAfter, bool *leftOf, double epsilon ) const
{
  double sqrDist = std::numeric_limits<double>::max();
  double testDist = 0;
  double segmentPtX, segmentPtY;

  int size = mX.size();
  if ( size == 0 || size == 1 )
  {
    vertexAfter = QgsVertexId( 0, 0, 0 );
    return -1;
  }
  for ( int i = 1; i < size; ++i )
  {
    double prevX = mX.at( i - 1 );
    double prevY = mY.at( i - 1 );
    double currentX = mX.at( i );
    double currentY = mY.at( i );
    testDist = QgsGeometryUtils::sqrDistToLine( pt.x(), pt.y(), prevX, prevY, currentX, currentY, segmentPtX, segmentPtY, epsilon );
    if ( testDist < sqrDist )
    {
      sqrDist = testDist;
      segmentPt.setX( segmentPtX );
      segmentPt.setY( segmentPtY );
      if ( leftOf )
      {
        *leftOf = ( QgsGeometryUtils::leftOfLine( pt.x(), pt.y(), prevX, prevY, currentX, currentY ) < 0 );
      }
      vertexAfter.part = 0;
      vertexAfter.ring = 0;
      vertexAfter.vertex = i;
    }
  }
  return sqrDist;
}

void QgsGeometryDuplicateNodesCheck::fixError( const QMap<QString, QgsFeaturePool *> &featurePools, QgsGeometryCheckError *error, int method, const QMap<QString, int> & /*mergeAttributeIndices*/, Changes &changes ) const
{
  QgsFeaturePool *featurePool = featurePools[ error->layerId() ];
  QgsFeature feature;
  if ( !featurePool->getFeature( error->featureId(), feature ) )
  {
    error->setObsolete();
    return;
  }
  QgsGeometry featureGeom = feature.geometry();
  QgsAbstractGeometry *geom = featureGeom.get();
  QgsVertexId vidx = error->vidx();

  // Check if point still exists
  if ( !vidx.isValid( geom ) )
  {
    error->setObsolete();
    return;
  }

  // Check if error still applies
  int nVerts = QgsGeometryCheckerUtils::polyLineSize( geom, vidx.part, vidx.ring );
  QgsPoint pi = geom->vertexAt( QgsVertexId( vidx.part, vidx.ring, ( vidx.vertex + nVerts - 1 ) % nVerts ) );
  QgsPoint pj = geom->vertexAt( error->vidx() );
  if ( QgsGeometryUtils::sqrDistance2D( pi, pj ) >= mContext->tolerance )
  {
    error->setObsolete();
    return;
  }

  // Fix error
  if ( method == NoChange )
  {
    error->setFixed( method );
  }
  else if ( method == RemoveDuplicates )
  {
    if ( !QgsGeometryCheckerUtils::canDeleteVertex( geom, vidx.part, vidx.ring ) )
    {
      error->setFixFailed( tr( "Resulting geometry is degenerate" ) );
    }
    else if ( !geom->deleteVertex( error->vidx() ) )
    {
      error->setFixFailed( tr( "Failed to delete vertex" ) );
    }
    else
    {
      feature.setGeometry( featureGeom );
      featurePool->updateFeature( feature );
      error->setFixed( method );
      changes[error->layerId()][error->featureId()].append( Change( ChangeNode, ChangeRemoved, error->vidx() ) );
    }
  }
  else
  {
    error->setFixFailed( tr( "Unknown method" ) );
  }
}

void QgsGeometryCheck::replaceFeatureGeometryPart( QgsFeature& feature, int partIdx, QgsAbstractGeometryV2* newPartGeom, Changes& changes ) const
{
  QgsAbstractGeometryV2* geom = feature.geometry()->geometry();
  if ( dynamic_cast<QgsGeometryCollectionV2*>( geom ) )
  {
    QgsGeometryCollectionV2* GeomCollection = static_cast<QgsGeometryCollectionV2*>( geom );
    GeomCollection->removeGeometry( partIdx );
    GeomCollection->addGeometry( newPartGeom );
    changes[feature.id()].append( Change( ChangeFeature, ChangeRemoved, QgsVertexId( partIdx ) ) );
    changes[feature.id()].append( Change( ChangeFeature, ChangeAdded, QgsVertexId( GeomCollection->partCount() - 1 ) ) );
  }
  else
  {
    feature.setGeometry( new QgsGeometry( newPartGeom ) );
    changes[feature.id()].append( Change( ChangeFeature, ChangeChanged ) );
  }
  mFeaturePool->updateFeature( feature );
}

bool QgsCurvePolygon::deleteVertex( QgsVertexId vId )
{
  if ( !mExteriorRing || vId.ring < 0 || vId.ring >= 1 + mInteriorRings.size() )
  {
    return false;
  }

  QgsCurve *ring = vId.ring == 0 ? mExteriorRing.get() : mInteriorRings.at( vId.ring - 1 );
  int n = ring->numPoints();
  if ( n <= 4 )
  {
    //no points will be left in ring, so remove whole ring
    if ( vId.ring == 0 )
    {
      mExteriorRing.reset();
      if ( !mInteriorRings.isEmpty() )
      {
        mExteriorRing.reset( mInteriorRings.takeFirst() );
      }
    }
    else
    {
      removeInteriorRing( vId.ring - 1 );
    }
    clearCache();
    return true;
  }

  bool success = ring->deleteVertex( vId );
  if ( success )
  {
    // If first or last vertex is removed, re-sync the last/first vertex
    // Do not use "n - 2", but "ring->numPoints() - 1" as more than one vertex
    // may have been deleted (e.g. with CircularString)
    if ( vId.vertex == 0 )
      ring->moveVertex( QgsVertexId( 0, 0, ring->numPoints() - 1 ), ring->vertexAt( QgsVertexId( 0, 0, 0 ) ) );
    else if ( vId.vertex == n - 1 )
      ring->moveVertex( QgsVertexId( 0, 0, 0 ), ring->vertexAt( QgsVertexId( 0, 0, ring->numPoints() - 1 ) ) );
    clearCache();
  }
  return success;
}

void TestQgsGeometryUtils::testAdjacentVertices()
{
    // test polygon - should wrap around!
    QgsLineString* closedRing1 = new QgsLineString();
    closedRing1->setPoints( QList<QgsPointV2>() << QgsPointV2( 1, 1 ) << QgsPointV2( 1, 2 ) << QgsPointV2( 2, 2 ) << QgsPointV2( 2, 1 ) << QgsPointV2( 1, 1 ) );
    QgsPolygonV2 polygon1;
    polygon1.setExteriorRing( closedRing1 );
    QgsVertexId previous;
    QgsVertexId next;

    QgsGeometryUtils::adjacentVertices( polygon1, QgsVertexId( 0, 0, 0 ), previous, next );
    QCOMPARE( previous, QgsVertexId( 0, 0, 3 ) );
    QCOMPARE( next, QgsVertexId( 0, 0, 1 ) );

    // test point - both vertices should be invalid
    QgsPointV2 point( 1, 2 );
    QgsGeometryUtils::adjacentVertices( point, QgsVertexId( 0, 0, 0 ), previous, next );
    QVERIFY( !previous.isValid() );
    QVERIFY( !next.isValid() );
}

void QgsGeometryLineIntersectionCheck::collectErrors( QList<QgsGeometryCheckError *> &errors, QStringList &/*messages*/, QAtomicInt *progressCounter, const QMap<QString, QgsFeatureIds> &ids ) const
{
  QMap<QString, QgsFeatureIds> featureIds = ids.isEmpty() ? allLayerFeatureIds() : ids;
  QgsGeometryCheckerUtils::LayerFeatures layerFeaturesA( mContext->featurePools, featureIds, mCompatibleGeometryTypes, progressCounter, true );
  QList<QString> layerIds = featureIds.keys();
  for ( const QgsGeometryCheckerUtils::LayerFeature &layerFeatureA : layerFeaturesA )
  {
    // Ensure each pair of layers only gets compared once: remove the current layer from the layerIds, but add it to the layerList for layerFeaturesB
    layerIds.removeOne( layerFeatureA.layer().id() );

    const QgsAbstractGeometry *geom = layerFeatureA.geometry();
    for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
    {
      const QgsLineString *line = dynamic_cast<const QgsLineString *>( QgsGeometryCheckerUtils::getGeomPart( geom, iPart ) );
      if ( !line )
      {
        // Should not happen
        continue;
      }

      // Check whether the line intersects with any other lines
      QgsGeometryCheckerUtils::LayerFeatures layerFeaturesB( mContext->featurePools, QList<QString>() << layerFeatureA.layer().id() << layerIds, line->boundingBox(), {QgsWkbTypes::LineGeometry} );
      for ( const QgsGeometryCheckerUtils::LayerFeature &layerFeatureB : layerFeaturesB )
      {
        // > : only report intersections within same layer once
        if ( layerFeatureA.layer().id() == layerFeatureB.layer().id() && layerFeatureB.feature().id() > layerFeatureA.feature().id() )
        {
          continue;
        }

        const QgsAbstractGeometry *testGeom = layerFeatureB.geometry();
        for ( int jPart = 0, mParts = testGeom->partCount(); jPart < mParts; ++jPart )
        {
          // Skip current feature part, only report intersections within same part once
          if ( layerFeatureB.feature().id() == layerFeatureA.feature().id() && iPart >= jPart )
          {
            continue;
          }
          const QgsLineString *testLine = dynamic_cast<const QgsLineString *>( QgsGeometryCheckerUtils::getGeomPart( testGeom, jPart ) );
          if ( !testLine )
          {
            continue;
          }
          const QList< QgsPoint > intersections = QgsGeometryCheckerUtils::lineIntersections( line, testLine, mContext->tolerance );
          for ( const QgsPoint &inter : intersections )
          {
            errors.append( new QgsGeometryCheckError( this, layerFeatureA, inter, QgsVertexId( iPart ), layerFeatureB.id() ) );
          }
        }
      }
    }
  }
}