//Include the graphics library.
#include "U8glib.h" 
//Initialize display.
U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NONE | U8G_I2C_OPT_DEV_0);

 #define DT 2
 #define CLK 3

 #define SW 4

int counter = 0;
int currentStateCLK;
int lastStateCLK;
String currentDir ="";

unsigned long lastButtonPress = 0;

 #define MENU_ITEMS 3
const char *menu_strings[MENU_ITEMS] = { "DASHBOARD", "SETTINGS", "CALIBRATE"};
void setup(void)
{
   pinMode (DT,INPUT);
   pinMode (CLK,INPUT);
   pinMode(SW, INPUT_PULLUP);
   lastStateCLK = digitalRead(CLK);

   Serial.begin(115200);
    //Set font.
    u8g.setFont(u8g_font_unifont);
}
void loop(void)
{
  rotary();
    u8g.firstPage();
    do {
      dashboard();
      // footer();
        // draw();
        // drawMenu();
    } while (u8g.nextPage());
    //Delay before repeating the loop.
    delay(50);
}
void draw(void)
{
    //Write text. (x, y, text)
    u8g.setFont(u8g_font_unifont);
    u8g.drawStr(25, 10, "MAIN MENU");
    u8g.drawHLine(0,12,128);  
    
}

void drawMenu(){
    u8g.setFont(u8g_font_5x7);
    int MenuY=25;
    for(int i=0;i<=MENU_ITEMS;i++){
    u8g.drawStr(5, MenuY, menu_strings[i]);
    MenuY += i+14;
    }
}

void dashboard(){
  //For Header Specification
  u8g.setFont(u8g_font_6x10r);
  u8g.drawStr(5, 8, "AXIS");
  u8g.drawStr(40, 8, "SPEED");
  u8g.drawStr(80, 8, "POSITION");
  u8g.drawHLine(0,12,128); 

//For Axis Specification
  u8g.setFont(u8g_font_5x8r);
  u8g.drawStr(10, 25, "X :");
  u8g.drawStr(10, 37, "Y :");
  u8g.drawStr(10, 49, "Z :");

//For Speed Specification
  u8g.setFont(u8g_font_5x8r);
  u8g.drawStr(40, 25, "2300");
  u8g.drawStr(40, 37, "5400");
  u8g.drawStr(40, 49, "1600");

  //For Position Specification
  u8g.setFont(u8g_font_5x8r);
  u8g.drawStr(80, 25, "2300");
  u8g.drawStr(80, 37, "5400");
  u8g.drawStr(80, 49, "1600");
}

void footer(){

  u8g.setFont(u8g_font_04b_24);
  u8g.drawStr(2, 60, "MAIN MENU > DASHBOARD");

}

void rotary(){
  // Read the current state of CLK
	currentStateCLK = digitalRead(CLK);

	// If last and current state of CLK are different, then pulse occurred
	// React to only 1 state change to avoid double count
	if (currentStateCLK != lastStateCLK  && currentStateCLK == 1){

		// If the DT state is different than the CLK state then
		// the encoder is rotating CCW so decrement
		if (digitalRead(DT) != currentStateCLK) {
			counter --;
			currentDir ="CCW";
		} else {
			// Encoder is rotating CW so increment
			counter ++;
			currentDir ="CW";
		}

		Serial.print("Direction: ");
		Serial.print(currentDir);
		Serial.print(" | Counter: ");
		Serial.println(counter);
	}

	// Remember last CLK state
	lastStateCLK = currentStateCLK;

	// Read the button state
	int btnState = digitalRead(SW);

	//If we detect LOW signal, button is pressed
	if (btnState == LOW) {
		//if 50ms have passed since last LOW pulse, it means that the
		//button has been pressed, released and pressed again
		if (millis() - lastButtonPress > 50) {
			Serial.println("Button pressed!");
		}

		// Remember last button press event
		lastButtonPress = millis();
	}

	// Put in a slight delay to help debounce the reading
	delay(1);
}