//#include <TEA5767.h>  // include Si4703_Breakout library to control FM Tuner
#include <Wire.h>  // include Wire library to use I2C to communicate with FM Tuner
#include <MD_Parola.h>
#include <MD_MAX72xx.h>
#include <SPI.h>

// initialize the LedControl library with the numbers of the interface pins with 4-digit 7-segment display 
#define HARDWARE_TYPE MD_MAX72XX::PAROLA_HW    //FC16_HW
#define MAX_DEVICES 4
#define CLK_PIN   13  // or SCK
#define DATA_PIN  11  // or MOSI
#define CS_PIN    10  // or SS


// initialize the Si4703_Breakout library with the numbers of the interface pins with FM Tuner
//TEA5767 Radio;

//define Arduino pins connected to encoder switch
int encoder_PB = 4;  // Push Button 
int encoder_A = 2;   // Phase A
int encoder_B = 3;   // Phase B
int encoder_A_Last = HIGH;  // last phase A state
int state_A;  // current phase A state
int state_PB; // current Push Button state


float channel_min = 87.25;  // Min. FM channel number = 87.5 MHz
float channel_max = 107.75;  // Max. FM channel number = 108.0 MHz
float channel;     // used to store current FM channel number
//favorite statios - total 22 channels
float station[7]= {87.00, 87.50, 97.50, 98.00, 101.00, 105.00, 108.00};
int list = 3;   // power on channel =  [list+1] =  18th channel = 104.1

MD_Parola myDisplay = MD_Parola(HARDWARE_TYPE, DATA_PIN, CLK_PIN, CS_PIN, MAX_DEVICES);

void setup()
{
  Serial.begin(9600);
  Wire.begin();
 
  pinMode (encoder_PB,INPUT);    // define pin mode for encoder switch
  pinMode (encoder_A,INPUT);
  pinMode (encoder_B,INPUT);

  myDisplay.begin();
  myDisplay.setIntensity(3);
  myDisplay.displayClear();


//  Radio.init();
  channel = station[list];   // set current channel number = (list + 1) channel

//  Radio.set_frequency(channel);
  

// initialize 4-digit 7-segment display
  
  displayFM(channel);    // show current channel number 
  delay(2000);
}

void loop()
{
  state_A = digitalRead(encoder_A);    //reading encoder phase A state
  state_PB = digitalRead(encoder_PB);  //reading encoder push button state
  
    if ((encoder_A_Last == LOW) && (state_A == HIGH))  // if phase A transit from LOW to HIGH
       {    
          if (digitalRead(encoder_B) == LOW)      // ** if phase B = LOW ==> clockwise rotation**
             {
                if(channel > channel_max)         // if channel higher than max channel number
                    channel = channel_min;        // starts over from min channel number
                else                              // otherwise, increase 0.2 channel number (200KHz)
                    channel = channel + 0.25; 
                //Radio.set_frequency(channel);
                displayFM(channel);               // display current channel number
                            
             } 
          else                                    // **if phase B = HIGH ==> counter-clockwise rotation**
             {
                if(channel < channel_min)         // if channel lower than min channel number
                    channel = channel_max;        // starts over from max channel number
                else                              // otherwise, decrease 0.2 channel number (200KHz)
                    channel = channel - 0.25; 
                //Radio.set_frequency(channel);
                displayFM(channel);               // display current channel number
                
             }
             Serial.println(channel);             
      }
     else if (state_PB == HIGH)     // if detecting Push Button being pressed
          {
            list++;                 // select next favorite station
            if(list == 7)          // if favorite statio reaches max number of favorite station
               list = 0;            // return to first list of favorite station numbe
            channel = station[list];       // set current favorite channel list number to current channel 
            //Radio.set_frequency(channel);
            displayFM(channel);            // display current channel number                
            delay(200);
            Serial.println(channel);
          }  
encoder_A_Last = state_A;    // update last Phase A state form current Phase A state
}

void displayFM(float number)   // subroutine for display current channel number
{
   /* 
    int num1,num2,num3,num4,num5;
    num1=number/10000;              // digit for thousands
    num2=(number%10000)/1000;        // digit for hundreds
    num3=(number%1000)/100;          // digit for tens
    num4=(number%100)/10;                // digit for units
    num5=number%10;                // digit for unit

*/

  myDisplay.setTextAlignment(PA_RIGHT);
  myDisplay.print(String(number));
   
}