//Libraries
#include  <Wire.h>                 //IDE Standard
#include <Rotary.h>               //Ben  Buxton https://github.com/brianlow/Rotary
#include <si5351.h>               //Etherkit  https://github.com/etherkit/Si5351Arduino
#include <Adafruit_GFX.h>         //Adafruit  GFX https://github.com/adafruit/Adafruit-GFX-Library
#include <Adafruit_SSD1306.h>     //Adafruit SSD1306 https://github.com/adafruit/Adafruit_SSD1306
#include <Adafruit_SH1106.h>

//User  preferences
//------------------------------------------------------------------------------------------------------------
#define  IF  1649                //Enter your IF frequency, ex: 455 = 455kHz, 10700 = 10.7MHz,  0 = to direct convert receiver or RF generator, + will add and - will subtract IF  offfset.
#define FREQ_INIT  7100100   //Enter your initial frequency at startup,  ex: 7000000 = 7MHz, 10000000 = 10MHz, 840000 = 840kHz.
#define XT_CAL_F   33000     //Si5351 calibration factor, adjust to get exatcly 10MHz. Increasing this value  will decreases the frequency and vice versa.
#define tunestep   A0        //Change  the pin used by encoder push button if you want.

#define OLED_RESET 4

//------------------------------------------------------------------------------------------------------------

Rotary  r = Rotary(2, 3);
Adafruit_SH1106 display(OLED_RESET);
Si5351  si5351;

unsigned long freq = FREQ_INIT;
unsigned long freqold, fstep;
long  interfreq = IF;
long cal = XT_CAL_F;
unsigned long long pll_freq = 90000000000ULL;
byte  encoder = 1;
byte stp;
unsigned int period = 100;   //millis display active
unsigned  long time_now = 0;  //millis display active

ISR(PCINT2_vect) {
  char  result = r.process();
  if (result == DIR_CW) set_frequency(1);
  else if  (result == DIR_CCW) set_frequency(-1);
}

//void set_frequency(short dir)  {
//  if (encoder == 1) {                         //Up/Down frequency
//    if  (dir == 1) freq = freq + fstep;
//    if (freq >= 120000000) freq = 120000000;
//    if (dir == -1) freq = freq - fstep;
//    if (fstep == 1000000 && freq <= 1000000)  freq = 1000000;
//    else if (freq < 10000) freq = 10000;
//  }
//}

void set_frequency(short dir)  {
  if (encoder == 1) {                         // Up/Down frequency
    if  (dir == 1) {
      freq = freq + fstep;
      if (freq > 7500000) freq = 6900000;  // Límite superior e inferior
    }
    if (dir == -1) {
      freq = freq - fstep;
      if (freq < 6900000) freq = 7500000;  // Límite superior e inferior
    }
    if (fstep == 1000000 && freq <= 6900000)  freq = 6900000;  // Ajuste mínimo permitido
    else if (freq >= 7500000) freq = 7500000;  // Ajuste máximo permitido
  }
}


void  setup() {
  Wire.begin();
  display.begin(SH1106_SWITCHCAPVCC, 0x3C);
  display.clearDisplay();
  display.setTextColor(WHITE);
  display.display();
  
  pinMode(2, INPUT_PULLUP);
  pinMode(3, INPUT_PULLUP);
  pinMode(tunestep,  INPUT_PULLUP);

  statup_text();

  si5351.init(SI5351_CRYSTAL_LOAD_8PF,  0, cal);
  si5351.output_enable(SI5351_CLK0, 1);                  //1 - Enable  / 0 - Disable CLK
  si5351.output_enable(SI5351_CLK1, 0);
  si5351.output_enable(SI5351_CLK2,  0);
  si5351.drive_strength(SI5351_CLK0, SI5351_DRIVE_2MA);  //Output current  2MA, 4MA, 6MA or 8MA


  PCICR |= (1 << PCIE2);
  PCMSK2 |= (1 << PCINT18)  | (1 << PCINT19);
  sei();

  stp = 3;
  setstep();
  layout();
  displayfreq();
}

void loop() {
  if (freqold != freq) {
    time_now  = millis();
    tunegen();
    freqold = freq;
  }

  if (digitalRead(tunestep)  == LOW) {
    time_now = (millis() + 300);
    setstep();
    delay(300);
  }

  if ((time_now + period) > millis()) {
    displayfreq();
    layout();
  }
}

void tunegen() {
  si5351.set_freq_manual((freq + (interfreq  * 1000ULL)) * 100ULL, pll_freq, SI5351_CLK0);
}

void displayfreq() {
  unsigned int m = freq / 1000000;
  unsigned int k = (freq % 1000000) / 1000;
  unsigned int h = (freq % 1000) / 1;

  display.clearDisplay();
  display.setTextSize(1);

  char buffer[15] = "";
  if (m < 1) {
    display.setCursor(41, 1); sprintf(buffer,  "%003d.%003d", k, h);
  }
  else if (m < 100) {
    display.setCursor(5,  1); sprintf(buffer, "%2d.%003d.%003d", m, k, h);
  }
  else if (m >= 100)  {
    unsigned int h = (freq % 1000) / 10;
    display.setCursor(5, 1); sprintf(buffer,  "%2d.%003d.%02d", m, k, h);
  }
  display.print(buffer);
}

void  setstep() {
  switch (stp) {
    case 1:
      stp = 2;
      fstep  = 10;
      break;
    case 2:
      stp = 3;
      fstep = 100;
      break;
    case 3:
      stp = 1;  // Cambiado de 4 a 1 para eliminar el paso de 1 MHz
      fstep = 1000;
      break;
    //case  4:
      //stp = 1;
      //fstep = 1000000;
      //break; // Comentado para eliminar el paso de 1 MHz
  }
}

void layout() {
  display.setTextColor(WHITE);
  display.drawLine(0, 20, 127, 20, WHITE);
  display.drawLine(0, 43, 127, 43,  WHITE);
  display.drawLine(105, 24, 105, 39, WHITE);
  display.setTextSize(1);
  display.setCursor(2, 25);
  display.print("Paso de:");
  if (stp == 2) display.print("10Hz");  if (stp == 3) display.print("100Hz"); if (stp == 1) display.print("1khz");
  //if  (stp == 1) display.print("1M");
  display.setCursor(2, 48);
 // display.print("FI:");
 // display.print(interfreq);
  display.print("Banda de 40M");
  //display.print("k");
  display.setTextSize(1);
  display.setCursor(110, 23);
  if (freq < 1000000) display.print("kHz");
  if (freq >= 1000000) display.print("MHz");
  display.setCursor(110, 33);
  if (interfreq == 0) display.print("VFO");
  if (interfreq != 0) display.print("VFO");
  display.display();
}

void statup_text() {
  display.setTextSize(1);
  display.setCursor(4, 5);
  display.print("CAHUANE FR-250");
  display.setCursor(4,  20);
  display.print("BANDA DE 40 Metros.");
  display.setCursor(4, 35);
  display.print("Matias Lavarini");
  display.setCursor(4, 50);
  display.print(">>  LU3VML <<");
  display.display();
  delay(5000);
  display.clearDisplay();
}