Helper.h

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#ifndef Helper_h
#define Helper_h
 
// Local includes.
#include "Configuration.h"
 
// Library include.
#include <ArduinoJson.h>
#if THINGSBOARD_ENABLE_STL
#include <iterator>
#endif // THINGSBOARD_ENABLE_STL
#include <stdint.h>
#include <assert.h>
#include <stdarg.h>
#include <stdio.h>
 
 
class Helper {
  public:
    template<typename... Args>
    static size_t Calculate_Print_Size(char const * format, Args const &... args) {
        const int result = snprintf(nullptr, 0U, format, args...) + 1U;
        assert(result > 0);
        return static_cast<size_t>(result);
    }
 
    static size_t Calculate_Symbol_Occurences(uint8_t const * bytes, char symbol, uint32_t length);
 
    static bool String_IsNull_Or_Empty(char const * str);
 
    static size_t Split_Topic_Into_Request_ID(char const * received_topic, size_t const & end_position);
 
    template <typename TSource>
    static size_t Measure_Json(TSource const & source) {
        return measureJson(source) + 1U;
    }
 
    template<typename InputIterator>
    static size_t distance(InputIterator const & first, InputIterator const & last) {
#if THINGSBOARD_ENABLE_STL
        return std::distance(first, last);
#else
        // Subtracting last by the first is only a valid way to calculate the distance if we can guarantee that the given iterators are random access,
        // to keep compatibility with code that supports the STL we allow InputIterators, therefore we have to implement the size calculation the more inneficient O(n) way instead.
        // This allows the edge case where an end-user uses this method themselves in the code with their own implemented list data type.
        size_t size = 0U;
        for (auto it = first; it != last; ++it, ++size) {}
        return size;
#endif // THINGSBOARD_ENABLE_STL
    }
};
 
#endif // Helper