#include "FadeLed.h"
#include <Wire.h> // I2C

// PINS
#define PIR1_PIN 2
#define PIR2_PIN 3
#define POT_MIN_PIN A0
#define POT_MAX_PIN A1

// States
#define RESTING 0
// #define ILLUMINATE 1
#define FADING 1
#define WAITING 2

// CONFIGURATION
#define CHANNELS 15 // number of stairs
#define FADE_TIME 1000
#define FADE_SPEED_STEP 100
#define FADE_PAUSE 500
#define FADE_CONSTANT true
#define TIME_ON 4000

#define UPWARDS true
#define DOWNWARDS false

// Settings
byte power_min_set = 0; // 0-100
byte power_max_set = 0; // 0-100

byte state = RESTING;



Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver();

FadeLed leds[CHANNELS] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 };

bool is_fading_in = false;
bool fade_direction = UPWARDS;
byte fade_power_target, fade_channel, fade_channel_max, fade_step, fade_speed;
unsigned long fade_pause_time = 0;

unsigned long waiting_previous_ms = 0;

void setup()
{
  Serial.begin(9600);

  pwm.begin();
  pwm.setPWMFreq(1000);

  FadeLed::linkPwm(pwm);

  // initDisplay();

  updateSettings(); // get min/max values


  // delay(4000);
    Serial.println("Hello Arduino\n");
  state = RESTING;
}

void startFade(bool power_up) {
  Serial.print("Starting fade. Powering up? ");
  Serial.println(power_up);
  is_fading_in = power_up;

  fade_power_target = power_up ? power_max_set : power_min_set;
  fade_channel = fade_direction ? 0 : CHANNELS-1;
  fade_channel_max = fade_direction ? CHANNELS-1 : 0;
  fade_step = fade_direction ? 1 : -1;
  fade_speed = FADE_TIME;

  state = FADING;
}

void loop()
{
  // FadeLed::update();
  // drawScreen(power_min_set, power_max_set);

  if(state == RESTING) {
        // Serial.println("Resting..");
      // drawScreen(power_min_set, power_max_set);
      updateSettings();

      // Check sensors
      byte pir_lower = digitalRead(PIR1_PIN);
      byte pir_upper = digitalRead(PIR2_PIN);

      // No trigger
      if(pir_lower == LOW && pir_upper == LOW) return;

      Serial.println("Trigger!");
      Serial.print(pir_lower);
      Serial.print(" - ");
      Serial.println(pir_upper);

      // TRIGGER - Set direction based on trigger location and start fade
      fade_direction = (pir_lower == HIGH) ? UPWARDS : DOWNWARDS;
      Serial.print("Fade direction: ");
      Serial.println(fade_direction);

      startFade(true);
  }
  else if (state == FADING) {
   // Check if pause is needed
      Serial.print("Fading channel: ");
      Serial.println(fade_channel);

      if(fade_pause_time > 0) {
        bool isPauseComplete = ((millis() - fade_pause_time) >= FADE_PAUSE);
        if(!isPauseComplete) return;

        fade_pause_time = 0; // Reset pause time
      }

      // Fade lights
      leds[fade_channel].setTime(fade_speed, FADE_CONSTANT);
      leds[fade_channel].set(fade_power_target);


      if(fade_channel == fade_channel_max) {
        // If fading is done, start waiting OR go to rest if fading out
        waiting_previous_ms = millis();
        fade_pause_time = 0;

        state = is_fading_in ? WAITING : RESTING;
        return;
      }

      // Move to next channel
      fade_channel += fade_step;
      fade_speed += FADE_SPEED_STEP;
      fade_pause_time = millis();

      return;
  }
  else if (state == WAITING) {
    Serial.println("Waiting");
    unsigned long currentMs = millis();

    bool isWaitComplete = ((currentMs - waiting_previous_ms) >= TIME_ON);
    if(!isWaitComplete) return;

    // If wait period is completed
    startFade(false);
  }

}

void updateSettings()
{
  // brightness values
  power_min_set = map(analogRead(POT_MIN_PIN), 10, 1023, 0, 100);
  power_max_set = map(analogRead(POT_MAX_PIN), 10, 1023, 0, 100);
}

// boolean hasTimePassed(int howLong, int startMs)
// {
//   unsigned long currentMs = millis();
//   return ((currentMs - startMs) >= howLong);
// }