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

 *

 * GEOS - Geometry Engine Open Source

 * http://geos.osgeo.org

 *

 * Copyright (C) 2022 Paul Ramsey <pramsey@cleverelephant.ca>

 *

 * This is free software; you can redistribute and/or modify it under

 * the terms of the GNU Lesser General Public Licence as published

 * by the Free Software Foundation.

 * See the COPYING file for more information.

 *

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

#include <geos/coverage/CoverageRing.h>

#include <geos/algorithm/Orientation.h>

#include <geos/geom/Coordinate.h>

#include <geos/geom/CoordinateSequence.h>

#include <geos/geom/Geometry.h>

#include <geos/geom/GeometryFactory.h>

#include <geos/geom/LineString.h>

#include <geos/geom/LinearRing.h>

#include <geos/geom/Polygon.h>

#include <geos/geom/util/PolygonExtracter.h>

#include <geos/util/IllegalStateException.h>

using geos::geom::Coordinate;

using geos::geom::CoordinateSequence;

using geos::geom::Geometry;

using geos::geom::GeometryFactory;

using geos::geom::LineString;

using geos::geom::LinearRing;

using geos::geom::Polygon;

namespace geos {     // geos

namespace coverage { // geos.coverage

/* public static */

bool

CoverageRing::isKnown(std::vector<CoverageRing*>& rings)

{

    for (auto* ring : rings) {

        if (! ring->isKnown())

            return false;

    }

    return true;

}

/* public */

CoverageRing::CoverageRing(const std::shared_ptr<const CoordinateSequence>& inPts, bool interiorOnRight)

    : noding::BasicSegmentString(inPts, nullptr)

    , m_isInteriorOnRight(interiorOnRight)

{

    m_isInvalid.resize(size() - 1, false);

    m_isMatched.resize(size() - 1, false);

}

/* public */

CoverageRing::CoverageRing(const LinearRing* ring, bool isShell)

    : CoverageRing(

        ring->getSharedCoordinates(),

        algorithm::Orientation::isCCW(ring->getCoordinatesRO()) != isShell)

{}

/* public */ 

geom::Envelope CoverageRing::getEnvelope(std::size_t start, std::size_t end) 

{

    geom::Envelope env;

    for (std::size_t i = start; i < end; i++) {

        env.expandToInclude(getCoordinate(i));

    }

    return env;

}

/* public */

bool

CoverageRing::isInteriorOnRight() const

{

    return m_isInteriorOnRight;

}

/* public */

void

CoverageRing::markInvalid(std::size_t index)

{

    m_isInvalid[index] = true;

}

/* public */

void

CoverageRing::markMatched(std::size_t index)

{

    m_isMatched[index] = true;

}

/* public */

bool

CoverageRing::isKnown() const

{

    for (size_t i = 0; i < m_isMatched.size(); i++ ) {

        if (!(m_isMatched[i] && m_isInvalid[i]))

            return false;

    }

    return true;

}

/* public */

bool

CoverageRing::isInvalid(std::size_t i) const

{

    return m_isInvalid[i];

}

/* public */

bool

CoverageRing::isInvalid() const

{

    for (bool b: m_isInvalid) {

        if (!b)

            return false;

    }

    return true;

}

/* public */

bool

CoverageRing::hasInvalid() const

{

    for (bool b: m_isInvalid) {

        if (b)

            return true;

    }

    return false;

}

/* public */

bool

CoverageRing::isKnown(std::size_t i) const

{

    return m_isMatched[i] || m_isInvalid[i];

}

/* public */

const Coordinate&

CoverageRing::findVertexPrev(std::size_t index, const Coordinate& pt) const

{

    std::size_t iPrev = index;

    const Coordinate* cPrev = &getCoordinate(iPrev);

    while (pt.equals2D(*cPrev)) {

        iPrev = prev(iPrev);

        cPrev = &getCoordinate(iPrev);

    }

    return *cPrev;

}

/* public */

const Coordinate&

CoverageRing::findVertexNext(std::size_t index, const Coordinate& pt) const

{

    //-- safe, since index is always the start of a segment

    std::size_t iNext = index + 1;

    const Coordinate* cNext = &getCoordinate(iNext);

    while (pt.equals2D(*cNext)) {

        iNext = next(iNext);

        cNext = &getCoordinate(iNext);

    }

    return *cNext;

}

/* public */

std::size_t

CoverageRing::prev(std::size_t index) const

{

    if (index == 0)

        return size() - 2;

    return index - 1;

}

/* public */

std::size_t

CoverageRing::next(std::size_t index) const

{

    if (index < size() - 2)

        return index + 1;

    return 0;

}

/* public */

void

CoverageRing::createInvalidLines(

    const GeometryFactory* geomFactory,

    std::vector<std::unique_ptr<LineString>>& lines)

{

    //-- empty case

    if (! hasInvalid()) {

        return;

    }

    //-- entire ring case

    if (isInvalid()) {

        std::unique_ptr<LineString> line = createLine(0, size() - 1, geomFactory);

        lines.push_back(std::move(line));

        return;

    }

    //-- find first end after index 0, to allow wrap-around

    std::size_t startIndex = findInvalidStart(0);

    std::size_t firstEndIndex = findInvalidEnd(startIndex);

    std::size_t endIndex = firstEndIndex;

    while (true) {

        startIndex = findInvalidStart(endIndex);

        endIndex = findInvalidEnd(startIndex);

        std::unique_ptr<LineString> line = createLine(startIndex, endIndex, geomFactory);

        lines.push_back(std::move(line));

        if (endIndex == firstEndIndex)

            break;

    }

}

/* private */

std::size_t

CoverageRing::findInvalidStart(std::size_t index)

{

    while (! isInvalid(index)) {

        index = nextMarkIndex(index);

    }

    return index;

}

/* private */

std::size_t

CoverageRing::findInvalidEnd(std::size_t index)

{

    index = nextMarkIndex(index);

    while (isInvalid(index)) {

        index = nextMarkIndex(index);

    }

    return index;

}

/* private */

std::size_t

CoverageRing::nextMarkIndex(std::size_t index)

{

    if (index >= m_isInvalid.size() - 1) {

        return 0;

    }

    return index + 1;

}

/* private */

std::unique_ptr<LineString>

CoverageRing::createLine(

    std::size_t startIndex,

    std::size_t endIndex,

    const GeometryFactory* geomFactory)

{

    std::unique_ptr<CoordinateSequence> linePts = endIndex < startIndex

        ? extractSectionWrap(startIndex, endIndex)

        : extractSection(startIndex, endIndex);

    return geomFactory->createLineString(std::move(linePts));

}

/* private */

std::unique_ptr<CoordinateSequence>

CoverageRing::extractSection(std::size_t startIndex, std::size_t endIndex)

{

    // std::size_t sz = endIndex - startIndex + 1;

    std::unique_ptr<CoordinateSequence> linePts(new CoordinateSequence());

    for (std::size_t i = startIndex; i <= endIndex; i++) {

        linePts->add(getCoordinate(i));

    }

    return linePts;

}

/* private */

std::unique_ptr<CoordinateSequence>

CoverageRing::extractSectionWrap(std::size_t startIndex, std::size_t endIndex)

{

    std::size_t sz = endIndex + (size() - startIndex);

    std::unique_ptr<CoordinateSequence> linePts(new CoordinateSequence);

    std::size_t index = startIndex;

    for (std::size_t i = 0; i < sz; i++) {

        linePts->add(getCoordinate(index));

        index = nextMarkIndex(index);

    }

    return linePts;

}

} // namespace geos.coverage

} // namespace geos