/******************************************************************************

 *

 * Project:  GDAL

 * Purpose:  "gdal vector convex-hull"

 * Author:   Daniel Baston

 *

 ******************************************************************************

 * Copyright (c) 2026, ISciences LLC

 *

 * SPDX-License-Identifier: MIT

 ****************************************************************************/

#include "gdalalg_vector_convex_hull.h"

#include "gdal_priv.h"

#include "ogrsf_frmts.h"

#include <cinttypes>

//! @cond Doxygen_Suppress

#ifndef _

#define _(x) (x)

#endif

GDALVectorConvexHullAlgorithm::GDALVectorConvexHullAlgorithm(

    bool standaloneStep)

    : GDALVectorGeomAbstractAlgorithm(NAME, DESCRIPTION, HELP_URL,

                                      standaloneStep, m_opts)

{

}

#ifdef HAVE_GEOS

namespace

{

class GDALVectorConvexHullAlgorithmLayer final

    : public GDALVectorGeomOneToOneAlgorithmLayer<GDALVectorConvexHullAlgorithm>

{

  public:

    GDALVectorConvexHullAlgorithmLayer(

        OGRLayer &oSrcLayer, const GDALVectorConvexHullAlgorithm::Options &opts)

        : GDALVectorGeomOneToOneAlgorithmLayer<GDALVectorConvexHullAlgorithm>(

              oSrcLayer, opts),

          m_poFeatureDefn(oSrcLayer.GetLayerDefn()->Clone())

    {

        // Convex hull output type can be Point/LineString/Polygon depending on input.

        // To avoid schema/type conflicts, advertise unknown geometry type for

        // processed geometry fields.

        for (int i = 0; i < m_poFeatureDefn->GetGeomFieldCount(); ++i)

        {

            if (IsSelectedGeomField(i))

                m_poFeatureDefn->GetGeomFieldDefn(i)->SetType(wkbUnknown);

        }

    }

    const OGRFeatureDefn *GetLayerDefn() const override

    {

        return m_poFeatureDefn.get();

    }

  protected:

    using GDALVectorGeomOneToOneAlgorithmLayer::TranslateFeature;

    std::unique_ptr<OGRFeature>

    TranslateFeature(std::unique_ptr<OGRFeature> poSrcFeature) const override

    {

        const int nGeomFieldCount = poSrcFeature->GetGeomFieldCount();

        for (int i = 0; i < nGeomFieldCount; ++i)

        {

            if (!IsSelectedGeomField(i))

                continue;

            if (const OGRGeometry *poGeom = poSrcFeature->GetGeomFieldRef(i))

            {

                std::unique_ptr<OGRGeometry> poHull(poGeom->ConvexHull());

                if (!poHull)

                {

                    CPLError(

                        CE_Failure, CPLE_AppDefined,

                        "Failed to compute convex hull of feature %" PRId64,

                        static_cast<int64_t>(poSrcFeature->GetFID()));

                    return nullptr;

                }

                poHull->assignSpatialReference(poGeom->getSpatialReference());

                poSrcFeature->SetGeomField(i, std::move(poHull));

            }

        }

        poSrcFeature->SetFDefnUnsafe(m_poFeatureDefn.get());

        return poSrcFeature;

    }

  private:

    const OGRFeatureDefnRefCountedPtr m_poFeatureDefn;

    CPL_DISALLOW_COPY_ASSIGN(GDALVectorConvexHullAlgorithmLayer)

};

}  // namespace

#endif  // HAVE_GEOS

std::unique_ptr<OGRLayerWithTranslateFeature>

GDALVectorConvexHullAlgorithm::CreateAlgLayer(

    [[maybe_unused]] OGRLayer &srcLayer)

{

#ifdef HAVE_GEOS

    return std::make_unique<GDALVectorConvexHullAlgorithmLayer>(srcLayer,

                                                                m_opts);

#else

    CPLAssert(false);

    return nullptr;

#endif

}

bool GDALVectorConvexHullAlgorithm::RunStep(GDALPipelineStepRunContext &ctxt)

{

#ifdef HAVE_GEOS

    return GDALVectorGeomAbstractAlgorithm::RunStep(ctxt);

#else

    (void)ctxt;

    ReportError(CE_Failure, CPLE_NotSupported,

                "This algorithm is only supported for builds against GEOS");

    return false;

#endif

}

GDALVectorConvexHullAlgorithmStandalone::

    ~GDALVectorConvexHullAlgorithmStandalone() = default;

//! @endcond