renderbug/src/inputs/CircadianRhythm.h

#pragma once
#include <Figments.h>
#include "../Platform.h"

struct ScheduleEntry {
  uint8_t hour;
  uint8_t brightness;
};

std::array<ScheduleEntry, 10> schedule{{
  {0, 0},
  {5, 0},
  {6, 0},
  {7, 10},
  {8, 80},
  {11, 120},
  {18, 200},
  {19, 255},
  {22, 120},
  {23, 20}
}};

class CircadianRhythm : public InputSource {
  private:
    bool needsUpdate = true;
  public:
    CircadianRhythm() : InputSource("CircadianRhythm") {}

    void onStart() {
      needsUpdate = true;
    }

    uint8_t brightnessForTime(uint8_t hour, uint8_t minute) const {
      ScheduleEntry start = schedule.back();
      ScheduleEntry end = schedule.front();
      for(ScheduleEntry cur : schedule) {
        // Find the last hour that is prior to or equal to now
        if (cur.hour <= hour) {
          start = cur;
        } else {
          break;
        }
      }
      for(ScheduleEntry cur : schedule) {
        // Find the first hour that is after now
        // If no such hour exists, we should automatically wrap back to hour 0
        if (cur.hour > hour) {
          end = cur;
          break;
        }
      }

      if (start.hour > end.hour) {
        end.hour += 24;
      }

      uint16_t startTime = start.hour * 60;
      uint16_t endTime = end.hour * 60;
      uint16_t nowTime = hour * 60 + minute;

      uint16_t duration = endTime - startTime;
      uint16_t curDuration = nowTime - startTime;

      uint8_t frac = map8(curDuration, 0, duration);

      return lerp8by8(start.brightness, end.brightness, frac);
    }


    InputEvent read() {
      EVERY_N_SECONDS(60) {
        needsUpdate = true;
      }
      if (needsUpdate) {
        uint8_t hour = 0;
        uint8_t minute = 0;
        needsUpdate = false;
        struct tm timeinfo;
        if (Platform::getLocalTime(&timeinfo)) {
          hour = timeinfo.tm_hour;
          minute = timeinfo.tm_min;
        } else {
          hour = 0;
          minute = 0;
        }
        Log.notice("Current time: %d:%d", hour, minute);
        auto brightness = brightnessForTime(hour, minute);
        Log.notice("Adjusting brightness to %d", brightness);
        return InputEvent{InputEvent::SetBrightness, brightness};
      }
      return InputEvent{};
    }
};