// ArduinoJson - https://arduinojson.org

// Copyright © 2014-2023, Benoit BLANCHON

// MIT License

#pragma once

#include <ArduinoJson/Array/JsonArrayIterator.hpp>

#include <ArduinoJson/Variant/VariantAttorney.hpp>

#include <ArduinoJson/Variant/VariantData.hpp>

ARDUINOJSON_BEGIN_PUBLIC_NAMESPACE

class JsonObject;

// A read-only reference to an array in a JsonDocument

// https://arduinojson.org/v6/api/jsonarrayconst/

class JsonArrayConst : public detail::VariantOperators<JsonArrayConst> {

  friend class JsonArray;

  friend class detail::VariantAttorney;

 public:

  typedef JsonArrayConstIterator iterator;

  // Returns an iterator to the first element of the array.

  // https://arduinojson.org/v6/api/jsonarrayconst/begin/

  FORCE_INLINE iterator begin() const {

    if (!data_)

      return iterator();

    return iterator(data_->head());

  }

  // Returns an iterator to the element following the last element of the array.

  // https://arduinojson.org/v6/api/jsonarrayconst/end/

  FORCE_INLINE iterator end() const {

    return iterator();

  }

  // Creates an unbound reference.

  FORCE_INLINE JsonArrayConst() : data_(0) {}

  // INTERNAL USE ONLY

  FORCE_INLINE JsonArrayConst(const detail::CollectionData* data)

      : data_(data) {}

  // Compares the content of two arrays.

  // Returns true if the two arrays are equal.

  FORCE_INLINE bool operator==(JsonArrayConst rhs) const {

    if (data_ == rhs.data_)

      return true;

    if (!data_ || !rhs.data_)

      return false;

    iterator it1 = begin();

    iterator it2 = rhs.begin();

    for (;;) {

      bool end1 = it1 == end();

      bool end2 = it2 == rhs.end();

      if (end1 && end2)

        return true;

      if (end1 || end2)

        return false;

      if (*it1 != *it2)

        return false;

      ++it1;

      ++it2;

    }

  }

  // Returns the element at the specified index.

  // https://arduinojson.org/v6/api/jsonarrayconst/subscript/

  FORCE_INLINE JsonVariantConst operator[](size_t index) const {

    return JsonVariantConst(data_ ? data_->getElement(index) : 0);

  }

  operator JsonVariantConst() const {

    return JsonVariantConst(collectionToVariant(data_));

  }

  // Returns true if the reference is unbound.

  // https://arduinojson.org/v6/api/jsonarrayconst/isnull/

  FORCE_INLINE bool isNull() const {

    return data_ == 0;

  }

  // Returns true if the reference is bound.

  // https://arduinojson.org/v6/api/jsonarrayconst/isnull/

  FORCE_INLINE operator bool() const {

    return data_ != 0;

  }

  // Returns the number of bytes occupied by the array.

  // https://arduinojson.org/v6/api/jsonarrayconst/memoryusage/

  FORCE_INLINE size_t memoryUsage() const {

    return data_ ? data_->memoryUsage() : 0;

  }

  // Returns the depth (nesting level) of the array.

  // https://arduinojson.org/v6/api/jsonarrayconst/nesting/

  FORCE_INLINE size_t nesting() const {

    return variantNesting(collectionToVariant(data_));

  }

  // Returns the number of elements in the array.

  // https://arduinojson.org/v6/api/jsonarrayconst/size/

  FORCE_INLINE size_t size() const {

    return data_ ? data_->size() : 0;

  }

 private:

  const detail::VariantData* getData() const {

    return collectionToVariant(data_);

  }

  const detail::CollectionData* data_;

};

template <>

struct Converter<JsonArrayConst> : private detail::VariantAttorney {

  static void toJson(JsonVariantConst src, JsonVariant dst) {

    variantCopyFrom(getData(dst), getData(src), getPool(dst));

  }

  static JsonArrayConst fromJson(JsonVariantConst src) {

    auto data = getData(src);

    return data ? data->asArray() : 0;

  }

  static bool checkJson(JsonVariantConst src) {

    auto data = getData(src);

    return data && data->isArray();

  }

};

ARDUINOJSON_END_PUBLIC_NAMESPACE