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// Arduino Brain Library - Brain Blinker

// Description: Basic brain example, blinks an LED on pin 13 faster as your "attention" value increases.
// Adapted from the Blink without Delay example distributed with Arduino environment.
// More info: https://github.com/kitschpatrol/Arduino-Brain-Library
// Author: Eric Mika, 2010 revised in 2014

#include <Brain.h>

// Set up the brain reader, pass it the hardware serial object you want to listen on.
Brain brain(Serial);

const int ledPin = 13; // 13 is handy because it's on the board.
long interval = 500; // Changes based on attention value.
long previousMillis = 0;
int ledState = LOW;

void setup() {
    // Set up the LED pin.
    pinMode(ledPin, OUTPUT);

    // Start the hardware serial.
    Serial.begin(9600);
}

void loop() {
    // Expect packets about once per second.
    if (brain.update()) {
        Serial.println(brain.readCSV());

        // Attention runs from 0 to 100.
        interval = (100 - brain.readAttention()) * 10;
    }

    // Make sure we have a signal.
    if(brain.readSignalQuality() == 0) {

        // Blink the LED.
      if (millis() - previousMillis > interval) {
        // Save the last time you blinked the LED.
        previousMillis = millis();

        // If the LED is off turn it on and vice-versa:
        if (ledState == LOW)
          ledState = HIGH;
        else
          ledState = LOW;

        // Set the LED with the ledState of the variable:
        digitalWrite(ledPin, ledState);
      }
    }
    else {
    digitalWrite(ledPin, LOW);
    }

}