//#include "DS1307RTC.h"
#include <Wire.h>

#define DS1307_ADD 0x68
#define SDA PB_3
#define SCL PB_2

unsigned int SETTED = false;
typedef struct {
  uint8_t s;
  uint8_t m;
  uint8_t h;
  uint8_t DW;
  uint8_t D;
  uint8_t M;
  uint8_t Y;

}_ctime;


uint8_t bcd2dec(uint8_t num);
uint8_t dec2bcd(uint8_t num);

uint8_t DIASMES(uint8_t MES){
  uint8_t meses[12] = {31 , 28, 31 , 30 , 31 , 30 , 31 , 31 , 30 , 31 , 30 ,31};
  return meses[MES%12];
}

static void(*proc)();

typedef union {
  uint8_t state = 0;
  struct{
    uint8_t isBerlim:1;
    uint8_t isAmPm:1;
  };

  void operator=(int in){
    (*this).state = in;
  }
}programStates_t;

programStates_t Programstate;

_ctime DSgetTime();


void nullf(){

}


void setData(){
  if(Serial.available()){
    String inputD  = Serial.readString();
    uint8_t buff;
    unsigned int vals = 8;
    for (int cont = 0 ; cont < a.length() ; cont++){
        switch(a[cont]){
            case '0':case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
            buff = buff*10 +  a[cont];
            break;
            default:
            vals += (vals<<(vals%0xFF));
            vals += 8;
        }
        buff+= a[cont];
    }
    proc = Menu;
  }
}

void readmenu(){
  char c = '\0';
  if(Serial.available()){
    c = Serial.read();
  }

  switch(c){
    case 'A':
    break;
    case 'C':
    break;
    case 'D':
    proc = setData;
    break;
    case 'F':
      Programstate.isBerlim = !Programstate.isBerlim;
    break;
    case 'W':case 'w':
      Programstate.isAmPm = !Programstate.isAmPm;
    break;
  }
}



void Menu(){
  Serial.println("A - Seta um Alarme");
  Serial.println("C - Cronômetro");
  Serial.println("D - Ajusta a Data");
  Serial.println("F - Fuso horário");
  Serial.println("H - Ajusta a hora");
  Serial.println("W - Ajusta o formato da hora");
  proc = readmenu;
}


void printdate(_ctime currentTime){
  if(Programstate.isBerlim && ((currentTime.h + 4) > 24)){
    currentTime.D = (currentTime.D + 1)%DIASMES(currentTime.M);
    currentTime.M = (currentTime.M +  ((currentTime.D + 1) >DIASMES(currentTime.M)))%12 + 1;
    currentTime.Y = currentTime.Y +   ((currentTime.D == 1)&&(currentTime.M == 1));
  }
  currentTime.h = (currentTime.h +  Programstate.isBerlim*4)%24;

  if(Programstate.isAmPm){
    Serial.print("Time: ");
    Serial.print(currentTime.D);
    Serial.print("/");
    Serial.print(currentTime.M);
    Serial.print("/");
    Serial.print(1982+currentTime.Y);
    Serial.print("   ");
    Serial.print((currentTime.h)%12 == 0 ? 12 : (currentTime.h)%12);
    Serial.print(":");
    Serial.print(currentTime.m);
    Serial.print(":");
    Serial.print(currentTime.s);
    Serial.print("  ");
    if(currentTime.h > 12){
      Serial.println("Pm");
    }else{
      Serial.println("Am");
    }
  }else{
    Serial.print("Time: ");
    Serial.print(currentTime.D);
    Serial.print("/");
    Serial.print(currentTime.M);
    Serial.print("/");
    Serial.print(1982+currentTime.Y);
    Serial.print("   ");
    Serial.print(currentTime.h);
    Serial.print(":");
    Serial.print(currentTime.m);
    Serial.print(":");
    Serial.println(currentTime.s);
  }
}

void setup() {
  Programstate = 0;
  Serial.begin(115200);
  Wire.begin();
  Serial.println("DS1307 Code");
  _ctime thistime;
  thistime.s = 0;
  thistime.m = 29;
  thistime.h = 21;
  thistime.DW = 2;
  thistime.D = 29;
  thistime.M = 5;
  thistime.Y = 23;
  //DSwriteTime(thistime);
  delay(1000);
  proc = Menu;
}

void loop() {
  static _ctime currentTime;
  proc();
  if(!(millis()%1000)){
    currentTime = DSgetTime();
    printdate(currentTime);
  }
  delay(2);
}


_ctime DSgetTime(){
  _ctime rtn;
  Wire.beginTransmission(DS1307_ADD);
  Wire.write((uint8_t)0x00);
  if(Wire.endTransmission() != 0){
    Serial.println("Not found");
    return rtn;
  }
  Wire.requestFrom(DS1307_ADD, 7);
  uint8_t avl = Wire.available();
  if (avl < 7){
    Serial.print("Avl: ");
    Serial.println(avl);
    return rtn;
  }
  rtn.s  =  bcd2dec(Wire.read()&0x7F);
  rtn.m  =  bcd2dec(Wire.read());
  rtn.h  =  bcd2dec(Wire.read()&0x3F);
  rtn.DW =  bcd2dec(Wire.read());
  rtn.D  =  bcd2dec(Wire.read());
  rtn.M  =  bcd2dec(Wire.read());
  rtn.Y  =  bcd2dec(Wire.read());

  return rtn;
}

uint8_t DSwriteTime(_ctime tm){
  Wire.beginTransmission(DS1307_ADD);
   Wire.write((uint8_t)0x00); // reset register pointer
  Wire.write((uint8_t)0x80); // Stop the clock. The seconds will be written last
  Wire.write(dec2bcd(tm.m));
  Wire.write(dec2bcd(tm.h));      // sets 24 hour format
  Wire.write(dec2bcd(tm.DW));
  Wire.write(dec2bcd(tm.D));
  Wire.write(dec2bcd(tm.M));
  Wire.write(dec2bcd(tm.Y)+30);

  if(Wire.endTransmission() != 0){
    Serial.println("Not found");
    return 0;
  }

  Wire.beginTransmission(DS1307_ADD);
  Wire.write((uint8_t)0x00); // reset register pointer
  Wire.write(dec2bcd(tm.s));

  if(Wire.endTransmission() != 0){
    Serial.println("Not found");
    return 0;
  }
  return 1;
}



uint8_t dec2bcd(uint8_t num){
  return ((num/10 * 16) + (num % 10));
}

// Convert Binary Coded Decimal (BCD) to Decimal
uint8_t bcd2dec(uint8_t num){
  return ((num/16 * 10) + (num % 16));
}