#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SH110X.h>
#include <Fonts/FreeMono9pt7b.h>
#include "myfont.h"

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET    -1
#define i2c_Address 0x3c
#define SDA_PIN 21 
#define SCL_PIN 22

Adafruit_SH1106G lcd = Adafruit_SH1106G(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET); // defining the oled display (just the name is lcd ,used one is oled)

void setup() {
    Serial.begin(115200);
    //Wire.begin(SDA_PIN, SCL_PIN);

    // if (!lcd.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { 
    //     Serial.println(F("SSD1306 allocation failed"));
    //     while (1);
    // }
    lcd.begin(i2c_Address, true);
    lcd.clearDisplay();
    // lcd.setFont(&FreeMono9pt7b);
    lcd.setFont(&Roboto_Light_14);
    lcd.setTextSize(1);
    lcd.setTextColor(SH110X_WHITE);
    lcd.setCursor(10, 25);
    lcd.print("Hello, World!");
    lcd.display();
}

void display_waveforms(long freq, int level, int attenuation, int wave_number, bool toggle) {
    freq = freq % 1000000000;             // making frequency<=1000000000 if needed
    wave_number = wave_number % 5;        // wave_number defines the wave currently being used
    lcd.clearDisplay();                   // to clear previous screen

      lcd.setCursor(0, 2 * 15);
      lcd.print("Lvl:");
      lcd.setCursor(0, 3 * 15);
      lcd.print("Fq:");


      String unit = "Hz";
      long dec = 0;
      if (freq >= 1000 && freq < 1000000) {
          dec = freq % 1000;
          freq = freq / 1000;
          unit = "K" + unit;                              //setting units for frequency as Hz or KHz or MHz
      } else if (freq >= 1000000 && freq < 1000000000) {
          dec = freq % 1000000;
          dec = dec / 1000;
          freq = freq / 1000000;
          unit = "M" + unit;
      }
      
      lcd.setCursor(6 * 8, 2 * 15);
      if (level>=1000)
      {
        lcd.print(level/1000);
        lcd.print(".");
        lcd.print((level%1000)/100);
        lcd.print((level%100)/10);
      }
      else
      {
        lcd.print(level);
        lcd.print("m");
      }
      //lcd.print(level);
      lcd.print("Vp-p");                                                   // V p-p
      lcd.setCursor(3 * 8, 3 * 15);                                        //location for print
      lcd.print((freq / 100) % 10);
      lcd.print(((freq % 100) / 10) % 10);                                 // making format of fff.fff units for frequency 
      lcd.print(freq % 10);
      lcd.print(".");
      lcd.print((dec / 100) % 10);
      lcd.print(((dec % 100) / 10) % 10);
      lcd.print(dec % 10);
      //lcd.setCursor(9 * 8, 3 * 15);
      lcd.print(unit);
      lcd.setCursor(0, 1 * 15);                  // setCursor(x,y) sets cursor to the given x,y in the display (in this case 128*64 oled) 
      lcd.print("Synthesized FGN");         // print(variable) prints the variable to the current cursor position
      lcd.setCursor(0, 4 * 15);
      lcd.print("Wave: ");

      lcd.setCursor(6 * 8, 4 * 15);

      const char* wave_types[] = {"Sine ", "Sqr ", "Ramp", "Pulse", "Tri "};            //to show the wave according to the wave number
      lcd.print(wave_types[wave_number]);
      lcd.print(attenuation);
      lcd.print("dB");


    lcd.display();                                                                 // display the changes
} 

int l=33;
int w=0;
int att=0;
long f=2100;
int s=0;
bool toggle = false;
String data="0010110";
void loop() 
{
  f+=20000;
  delay(500);
  display_waveforms(f,l,att,w, toggle);
  toggle = !toggle;

  l+=100;
  w=(w+1)%5;
  att++;
  s=1-s;

}