#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

#define CLK 2
#define DT  3
#define SW  4
#define EXTRA_LED 6

int lastClk;
int bright = 0;

void setup() {
  pinMode(CLK, INPUT_PULLUP);
  pinMode(DT, INPUT_PULLUP);
  pinMode(SW, INPUT_PULLUP);
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(EXTRA_LED, OUTPUT);
  lastClk = digitalRead(CLK);

  //OLED初始化
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
}

void loop() {
  int clkVal = digitalRead(CLK);
  int dtVal  = digitalRead(DT);

  if(clkVal != lastClk)
  {
    if(dtVal != clkVal)
    {
      bright +=5;
      if(bright>255) bright=255;
    }else{
      bright -=5;
      if(bright<0) bright=0;
    }
    analogWrite(LED_BUILTIN, bright);
    analogWrite(EXTRA_LED, bright);
    lastClk = clkVal;

    //计算百分比
    int percent = map(bright,0,255,0,100);
    display.clearDisplay();
    display.setCursor(0,0);
    display.print("Brightness: ");
    display.print(percent);
    display.println(" %");
    display.display();
  }

  if(digitalRead(SW) == LOW)
  {
    bright = 0;
    analogWrite(LED_BUILTIN, bright);
    analogWrite(EXTRA_LED, bright);
    int percent = map(bright,0,255,0,100);
    display.clearDisplay();
    display.setCursor(0,0);
    display.print("Brightness: ");
    display.print(percent);
    display.println(" %");
    display.display();
    delay(200);
  }
  delay(10);
}