price_speedometer/circular_buffer.mqh

#ifndef CIRCULAR_BUFFER_MQH
#define CIRCULAR_BUFFER_MQH

template <typename Type> class Circular_buffer {
protected:
  Type array[];
  const int capacity;
  int write_position;
  int size;

public:
  Circular_buffer(const int &_capacity)
      : capacity(_capacity), write_position(0), size(0) {
    const int new_size = capacity;
    if (ArrayResize(array, new_size) == -1) {
      Print("Cannot resize the array!");
    }
  }

  Circular_buffer(const Circular_buffer &circular_buffer)
      : capacity(circular_buffer.capacity),
        write_position(circular_buffer.write_position),
        size(circular_buffer.size) {
    const int new_size = capacity;
    if (ArrayResize(array, new_size) == -1) {
      Print("Cannot resize the array!");
    }
    for (int position = 0; position < capacity; ++position) {
      array[position] = circular_buffer.array[position];
    }
  }

  virtual ~Circular_buffer() { ArrayFree(array); }

public:
  Circular_buffer operator=(const Circular_buffer &circular_buffer) {
    for (int position = 0; position < capacity; ++position) {
      array[position] = circular_buffer.array[position];
    }
    write_position = circular_buffer.write_position;
    size = circular_buffer.size;
    return *this;
  }

public:
  int get_size() const { return size; }

  void write(const Type &value) {
    array[write_position] = value;
    write_position = (write_position + 1) % capacity;
    if (size >= capacity) {
      return;
    }
    ++size;
    return;
  }

  bool read(int position_offset, Type &value) const {
    if (position_offset < 0 || position_offset >= size) {
      return false;
    }
    const int read_position =
        (write_position - 1 - position_offset + capacity) % capacity;
    value = array[read_position];
    return true;
  }
};

#endif