#define LEDC_TIMER_12_BIT  12   // Use 12-bit precision for the LEDC timer
#define LEDC_BASE_FREQ     5000 // Use 5000 Hz as the LEDC base frequency
#define LED_PIN            A0   // Fade LED PIN (replace with LED_BUILTIN constant for the built-in LED)

int brightness = 0;       // How bright the LED is
int maxBrightness = 200;  // value must be between 0 and 255
// Arduino-like analogWrite
// Value has to be between 0 and valueMax
void ledcAnalogWrite(uint8_t pin, uint32_t value, uint32_t valueMax = 255) {
  // Calculate duty, 4095 from 2 ^ 12 - 1
  uint32_t duty = (4095 / valueMax) * min(value, valueMax);

  // Write duty to LEDC
  ledcWrite(pin, duty);
}

void setup() {
  Serial.begin(115200);
  Serial.setDebugOutput(true);
  // Setup timer and attach timer to the LED pin
  ledcAttach(LED_PIN, LEDC_BASE_FREQ, LEDC_TIMER_12_BIT);
}

void loop() {
  receiveBeat();
  //heartBeat(); // 10/10 loco jaja
  
  Serial.printf("demo done");

  delay(100000);
  
}


/*
  Beats like sistole/diastole in a single led. 
  uses maxBrightness, brightness

*/
void heartBeat(){

  brightness = 0;
  int rampUp = 40;
  int atenuate =  0; // percentage of the full brightness to reach on the atenuation part
  int goDown = 20;
  int delayAmount = 10;  // ms between steps 


  atenuate = maxBrightness*atenuate/100; // now contains the abs atenuation output


  // beat 3 times
  for(int i = 0; i < 3; i++){
    int phase = 0;
    while (phase <= 4){
      switch(phase){
        case 0:
        case 2:
          // goes up at rampUp speed
          while (brightness < maxBrightness){
            brightness = min(brightness+rampUp, maxBrightness);
            ledcAnalogWrite(LED_PIN, brightness);
            delay(delayAmount);
          }
          phase++; break;
          delay(delayAmount);
        
        // goes down until atenuation point 
        case 1:
          while (brightness > atenuate){
            brightness = max(brightness-goDown, atenuate);
            ledcAnalogWrite(LED_PIN, brightness);
            delay(delayAmount);
          }
          phase++; break;  
        
        // goes down finally at goDown speed
        case 3:
          while (brightness > 0){
            brightness = max(brightness-goDown, 0);
            ledcAnalogWrite(LED_PIN, brightness);
            delay(delayAmount);
          }
          phase++; break;  
        
        // wait between heartbeats
        case 4:
          delay(1000);
          phase++;
          break;
      }
    }
  }


}

/*
  Kind of beating the led does when receiving a beat request.
  uses maxBrightness
*/
void receiveBeat(){

  int step = 15;
  int phase = 0;
  int delayAmount = 50;  // ms between steps 

  // beat 3 times
  for(int i = 0; i < 3; i++){
    phase = 0;
    brightness = 0; // reset brightness

    while (phase <= 3){
      switch(phase){
        case 0:
          while (brightness < maxBrightness){
            brightness = min(brightness+step, maxBrightness);
            ledcAnalogWrite(LED_PIN, brightness);
            delay(delayAmount);
          }
          phase++; break;
        
        case 1:
          delay(100); // stay at the top for a lil'
          phase++;break;
        // goes down until 0
        case 2:
          while (brightness > 0){
            brightness = max(brightness-step, 0);
            ledcAnalogWrite(LED_PIN, brightness);
            delay(delayAmount);
          }
          phase++; break;  
        
        // wait between heartbeats
        case 3:
          delay(1000);
          phase++;
          break;
      }
    }
  }


}