/*

 * Copyright 2018-2021 Uber Technologies, Inc.

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *         http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

/** @file polygon.c

 * @brief Polygon (GeoLoop) algorithms

 */

#include "polygon.h"

#include <float.h>

#include <math.h>

#include <stdbool.h>

#include "bbox.h"

#include "constants.h"

#include "h3api.h"

#include "latLng.h"

#include "linkedGeo.h"

// Define macros used in polygon algos for GeoLoop

#define TYPE GeoLoop

#define INIT_ITERATION INIT_ITERATION_GEOFENCE

#define ITERATE ITERATE_GEOFENCE

#define IS_EMPTY IS_EMPTY_GEOFENCE

#include "polygonAlgos.h"

#undef TYPE

#undef INIT_ITERATION

#undef ITERATE

#undef IS_EMPTY

/**

 * Create a bounding box from a GeoPolygon

 * @param polygon Input GeoPolygon

 * @param bboxes  Output bboxes, one for the outer loop and one for each hole

 */

void bboxesFromGeoPolygon(const GeoPolygon *polygon, BBox *bboxes) {

    bboxFromGeoLoop(&polygon->geoloop, &bboxes[0]);

    for (int i = 0; i < polygon->numHoles; i++) {

        bboxFromGeoLoop(&polygon->holes[i], &bboxes[i + 1]);

    }

}

/**

 * pointInsidePolygon takes a given GeoPolygon data structure and

 * checks if it contains a given geo coordinate.

 *

 * @param geoPolygon The geoloop and holes defining the relevant area

 * @param bboxes     The bboxes for the main geoloop and each of its holes

 * @param coord      The coordinate to check

 * @return           Whether the point is contained

 */

bool pointInsidePolygon(const GeoPolygon *geoPolygon, const BBox *bboxes,

                        const LatLng *coord) {

    // Start with contains state of primary geoloop

    bool contains =

        pointInsideGeoLoop(&(geoPolygon->geoloop), &bboxes[0], coord);

    // If the point is contained in the primary geoloop, but there are holes in

    // the geoloop iterate through all holes and return false if the point is

    // contained in any hole

    if (contains && geoPolygon->numHoles > 0) {

        for (int i = 0; i < geoPolygon->numHoles; i++) {

            if (pointInsideGeoLoop(&(geoPolygon->holes[i]), &bboxes[i + 1],

                                   coord)) {

                return false;

            }

        }

    }

    return contains;

}