/*
    * Copyright 2015-2022 the original author or authors.
    *
    * 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.
   */
  
  package org.bremersee.geojson;
  
  import static java.util.Objects.isNull;
  import static java.util.Objects.nonNull;
  
  import com.fasterxml.jackson.annotation.JsonCreator;
  import com.fasterxml.jackson.annotation.JsonIgnore;
  import com.fasterxml.jackson.annotation.JsonInclude;
  import com.fasterxml.jackson.annotation.JsonInclude.Include;
  import com.fasterxml.jackson.annotation.JsonProperty;
  import com.fasterxml.jackson.annotation.JsonPropertyOrder;
  import io.swagger.v3.oas.annotations.media.Schema;
  import io.swagger.v3.oas.annotations.media.Schema.RequiredMode;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Comparator;
  import java.util.List;
  import java.util.Objects;
  import java.util.Optional;
  import java.util.stream.Collectors;
  import org.bremersee.geojson.model.UnknownAware;
  import org.locationtech.jts.geom.Geometry;
  
  /**
   * A GeoJSON object with the type {@code FeatureCollection} is a feature collection object (see
   * <a href="https://tools.ietf.org/html/rfc7946#section-3.3">rfc7946 section 3.3</a>).
   *
   * @param <G> the geometry type parameter
   * @param <P> the properties type parameter
   * @author Christian Bremer
   */
  @Schema(description = "A GeoJSON object with type 'Feature'.")
  @JsonPropertyOrder({"type", "bbox", "features"})
  public class GeoJsonFeatureCollection<G extends Geometry, P> extends UnknownAware {
  
    @Schema(hidden = true)
    @JsonIgnore
    private final boolean withBoundingBox;
  
    @Schema(hidden = true)
    @JsonIgnore
    private final Comparator<GeoJsonFeature<G, P>> comparator;
  
    @Schema(description = "The bounding box of the GeoJSON feature collection.")
    @JsonInclude(Include.NON_EMPTY)
    @JsonProperty(GeoJsonConstants.BBOX)
    private double[] bbox;
  
    @Schema(description = "The features the GeoJSON feature collection.")
    @JsonInclude(Include.ALWAYS)
    @JsonProperty(GeoJsonConstants.FEATURES)
    private final List<GeoJsonFeature<G, P>> features;
  
    /**
     * Instantiates a new Geo json feature collection.
     *
     * @param bbox the bbox
     * @param features the features
     * @param comparator the comparator
     */
    public GeoJsonFeatureCollection(
        double[] bbox,
        Collection<? extends GeoJsonFeature<G, P>> features,
        Comparator<GeoJsonFeature<G, P>> comparator) {
  
      if (isNull(bbox) || (bbox.length == 4) || (bbox.length == 6)) {
        this.bbox = bbox;
      } else {
        throw new IllegalArgumentException(
            "Bounding box must be null or must have a length of four or six.");
      }
      this.withBoundingBox = nonNull(this.bbox);
      this.comparator = comparator;
      this.features = new ArrayList<>();
      addAll(features);
    }
  
    /**
     * Instantiates a new geo json feature collection.
     *
     * @param bbox the bbox
    * @param features the features
    */
   public GeoJsonFeatureCollection(
       double[] bbox,
       Collection<? extends GeoJsonFeature<G, P>> features) {
 
     this(bbox, features, null);
   }
 
   /**
    * Instantiates a new Geo json feature collection.
    *
    * @param features the features
    * @param calculateBounds the calculate bounds
    */
   public GeoJsonFeatureCollection(
       Collection<? extends GeoJsonFeature<G, P>> features,
       boolean calculateBounds) {
 
     this(
         calculateBounds
             ? GeoJsonGeometryFactory.getBoundingBox(getGeometries((features)))
             : null,
         features,
         null);
   }
 
   /**
    * Instantiates a new Geo json feature collection.
    *
    * @param features the features
    * @param calculateBounds the calculate bounds
    * @param comparator the comparator
    */
   public GeoJsonFeatureCollection(
       Collection<? extends GeoJsonFeature<G, P>> features,
       boolean calculateBounds, Comparator<GeoJsonFeature<G, P>> comparator) {
 
     this(
         calculateBounds
             ? GeoJsonGeometryFactory.getBoundingBox(getGeometries((features)))
             : null,
         features,
         comparator);
   }
 
   /**
    * Instantiates a new Geo json feature collection.
    *
    * @param withBoundingBox the with bounding box
    * @param comparator the comparator
    */
   public GeoJsonFeatureCollection(
       boolean withBoundingBox,
       Comparator<GeoJsonFeature<G, P>> comparator) {
 
     this.withBoundingBox = withBoundingBox;
     this.features = new ArrayList<>();
     this.comparator = comparator;
   }
 
   /**
    * Instantiates a new geo json feature collection.
    *
    * @param withBoundingBox the with bounding box
    */
   public GeoJsonFeatureCollection(boolean withBoundingBox) {
     this(withBoundingBox, null);
   }
 
   /**
    * Instantiates a new geo json feature collection.
    *
    * @param type the type
    * @param bbox the bbox
    * @param features the features
    */
   @JsonCreator
   GeoJsonFeatureCollection(
       @JsonProperty(value = GeoJsonConstants.TYPE, required = true) String type,
       @JsonProperty(GeoJsonConstants.BBOX) double[] bbox,
       @JsonProperty(GeoJsonConstants.FEATURES)
       Collection<? extends GeoJsonFeature<G, P>> features) {
 
     this(bbox, features, null);
     if (!GeoJsonConstants.FEATURE_COLLECTION.equals(type)) {
       throw new IllegalArgumentException(String
           .format("Type must be '%s'.", GeoJsonConstants.FEATURE_COLLECTION));
     }
   }
 
   /**
    * Gets type.
    *
    * @return the type
    */
   @Schema(
       description = "The feature collection type.",
       requiredMode = RequiredMode.REQUIRED,
       example = GeoJsonConstants.FEATURE_COLLECTION)
   @JsonProperty(value = GeoJsonConstants.TYPE, required = true)
   public final String getType() {
     return GeoJsonConstants.FEATURE_COLLECTION;
   }
 
   /**
    * Return the bounding box of the GeoJSON object or {@code null} if there is no such object (see
    * <a href="https://tools.ietf.org/html/rfc7946#section-5">Bounding Box</a>).
    *
    * @return the bounding box
    */
   @JsonIgnore
   public double[] getBbox() {
     return bbox;
   }
 
   /**
    * Gets features.
    *
    * @return the features
    */
   @JsonIgnore
   public List<GeoJsonFeature<G, P>> getFeatures() {
     return isNull(features) ? List.of() : Collections.unmodifiableList(features);
   }
 
   /**
    * Add.
    *
    * @param feature the feature
    */
   public void add(GeoJsonFeature<G, P> feature) {
     if (nonNull(feature)) {
       addAll(List.of(feature));
     }
   }
 
   /**
    * Add all.
    *
    * @param features the features
    */
   public void addAll(Collection<? extends GeoJsonFeature<G, P>> features) {
     if (nonNull(features) && !features.isEmpty()) {
       this.features.addAll(features);
       if (withBoundingBox) {
         this.bbox = GeoJsonGeometryFactory.getBoundingBox(getGeometries(this.features));
       }
       if (nonNull(comparator)) {
         this.features.sort(this.comparator);
       }
     }
   }
 
   @Override
   public boolean equals(Object o) {
     if (this == o) {
       return true;
     }
     if (!(o instanceof GeoJsonFeatureCollection<?, ?> that)) {
       return false;
     }
     return Arrays.equals(getBbox(), that.getBbox())
         && Objects.equals(getFeatures(), that.getFeatures());
   }
 
   @Override
   public int hashCode() {
     int result = Objects.hash(getFeatures());
     result = 31 * result + Arrays.hashCode(getBbox());
     return result;
   }
 
   @Override
   public String toString() {
     return "GeoJsonFeatureCollection {"
         + ", features=" + getFeatures()
         + ", bbox=" + Arrays.toString(getBbox())
         + ", unknown=" + unknown()
         + '}';
   }
 
   @SuppressWarnings("unchecked")
   private static List<Geometry> getGeometries(Collection<?> features) {
     return Optional.ofNullable(features)
         .stream()
         .flatMap(Collection::stream)
         .map(obj -> ((GeoJsonFeature<Geometry, ?>) obj).getGeometry())
         .filter(Objects::nonNull)
         .collect(Collectors.toList());
   }
 }