#include <Wire.h> // library requires for I2C communication
#include <Adafruit_SSD1306.h>
#include <Encoder.h>

// Encoder myEnc(2, 3);
// int encVal = 0;
// int encOldVal = 0;

const unsigned int MAX_MESSAGE_LENGTH = 25;
char message[MAX_MESSAGE_LENGTH];

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

unsigned long oldOledTime = 0;

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

int progress = 0; // progress of the progressbar

void setup() {
	Serial.begin(115200);
	
	display.begin(SSD1306_SWITCHCAPVCC, 0x3C);

	Serial.println("arduino ready");
}

void loop() {

	// int encVal = myEnc.read();
	// if (encVal != encOldVal) {
	// 	encOldVal = encVal;
	// 	Serial.println(encVal);
	// }

	//Check to see if anything is available in the serial receive buffer
	while (Serial.available() > 0) {
		//Create a place to hold the incoming message
		static unsigned int message_pos = 0;

		//Read the next available byte in the serial receive buffer
		char inByte = Serial.read();

		//Message coming in (check not terminating character) and guard for over message size
		if ( inByte != '\n' && (message_pos < MAX_MESSAGE_LENGTH - 1) )
		{
			//Add the incoming byte to our message
			message[message_pos] = inByte;
			message_pos++;
		}
		//Full message received...
		else
		{
			//Add null character to string
			message[message_pos] = '\0';

			//Print the message (or do other things)
			//Serial.println(message);

			//Reset for the next message
			message_pos = 0;
		}
	}

	// OLED drawing
	if (millis() - oldOledTime > 10) {

		oldOledTime = millis();
		display.clearDisplay();
		display.setTextSize(1);
		display.setTextColor(SSD1306_WHITE);
		display.setCursor(5, 7);
		display.print(message);
		display.drawRect(5, 18, 116, 39, 1);
		display.fillRect(8, 21, progress, 33, 1);
		display.display();

		// increase the progress value to go over 0-100
		progress = progress + 1;
		if (progress > 110) {
			progress = 0;
		}
	}		
}