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

#define SCREEN_WIDTH 128 // OLED width,  in pixels
#define SCREEN_HEIGHT 64 // OLED height, in pixels

// create an OLED display object connected to I2C
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);





void setup() {
  Serial.begin(9600);

  // initialize OLED display with I2C address 0x3C
  if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("failed to start SSD1306 OLED"));
    while (1);
  }

  delay(1000);         // wait two seconds for initializing

  oled.clearDisplay(); // clear display


  oled.setTextSize(1);         // set text size
  oled.setTextColor(WHITE);    // set text color
  oled.setCursor(10, 30);       // set position to display (x,y)
  oled.println("Sistema Iniciado...");         // set text


  oled.drawLine(2,5,SCREEN_WIDTH-2,5, WHITE); // x0 y0 x1 y1
  oled.drawLine(2,SCREEN_HEIGHT-5,SCREEN_WIDTH-2,SCREEN_HEIGHT-5, WHITE);
  

  oled.display();              // display on OLED

  delay(100);

  // Scroll in various directions, pausing in-between:
  oled.startscrollright(0x00, 0x0F);
  delay(1000);
  oled.stopscroll();
  delay(1000);
  oled.startscrollleft(0x00, 0x0F);
  delay(1000);
  oled.stopscroll();
  delay(1000);
  oled.startscrolldiagright(0x00, 0x07);
  delay(1000);
  oled.startscrolldiagleft(0x00, 0x07);
  delay(2000);
  oled.stopscroll();

}


int i;
void loop() {

  delay(2000);

  oled.clearDisplay();  // Clear display buffer

  //  drawLine...
  for(i=0; i<oled.width(); i+=4) {
    oled.drawLine(0, oled.height()-1, i, 0, SSD1306_WHITE);
    oled.display();
    delay(1);
  }
  for(i=oled.height()-1; i>=0; i-=4) {
    oled.drawLine(0, oled.height()-1, oled.width()-1, i, SSD1306_WHITE);
    oled.display();
    delay(1);
  }
  delay(250);

  oled.clearDisplay();

  // Draw rectangles (outlines)
  for(i=0; i<oled.height()/2; i+=2) {
    if(i%4==0)  oled.drawRect(i, i, oled.width()-2*i, oled.height()-2*i, SSD1306_WHITE);        
    else   oled.drawRoundRect(i, i, oled.width()-2*i, oled.height()-2*i, oled.height()/4, SSD1306_WHITE);                    
    oled.display(); // Update screen with each newly-drawn rectangle
    delay(10);
  }


  oled.clearDisplay();

  for(i=0; i<oled.height()/2; i+=3) {
    // The INVERSE color is used so rectangles alternate white/black
    oled.fillRect(i, i, oled.width()-i*2, oled.height()-i*2, SSD1306_INVERSE);
    oled.display(); // Update screen with each newly-drawn rectangle
    delay(1);
  }

  delay(250);
  oled.clearDisplay();

  for(i=0; i<max(oled.width(),oled.height())/2; i+=2) {
    oled.drawCircle(oled.width()/2, oled.height()/2, i, SSD1306_WHITE);
    oled.display();
    delay(1);
  }

  delay(2000);


}