#pragma once

#include <array>
#include <cstddef>
#include <cstdint>

namespace roro {

// Smooths battery voltage samples and turns them into a charge percentage.
class BatteryEstimator {
   public:
    // Typical single-cell LiPo discharge curve under light load.
    static int percentFromMillivolts(int millivolts);

    void addSample(int millivolts);
    bool hasReading() const { return count_ > 0; }
    int millivolts() const;  // median of the recent samples
    int percent() const { return percentFromMillivolts(millivolts()); }

   private:
    static constexpr size_t kWindow = 8;
    std::array<int, kWindow> samples_{};
    size_t next_ = 0;
    size_t count_ = 0;
};

}  // namespace roro