// Arduino Audio Recorder


#include <SdFat.h> // https://yadi.sk/d/zqi8-L5xruhFq
#include <EEPROM.h>

#include <RTClib.h>

#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))

SdFat sd;
SdFile rec;
RTC_DS1307 rtc;

const int chipSelect = 4; /* Поменял на 10-pln */
unsigned long fileSize = 0L;
unsigned long waveChunk = 16;
unsigned int waveType = 1;
unsigned int numChannels = 1;
unsigned long sampleRate = 22050;
unsigned long bytesPerSec = 22050;
unsigned int blockAlign = 1;
unsigned int bitsPerSample = 8;
unsigned long dataSize = 0L;
unsigned long recByteCount = 0L;
unsigned long recByteSaved = 0L;
const int btnStart = 6;
const int btnStop = 5;
const int ledStart = 2;
const int ledStop = 3;
int recPressed = 0;
int stopPressed = 0;
unsigned long oldTime = 0L;
unsigned long newTime = 0L;
byte buf00[386]; // buffer array 1
byte buf01[386]; // buffer array 2
byte byte1, byte2, byte3, byte4;
unsigned int bufByteCount;
byte bufWrite;

unsigned long timer1;
int timer1on = 0;
//----------
//char NameRecord[4]; /* Имя нового - записываемого файла на SD-карту. */
int RecordNumber; /* Номер записи - храним в EEPROM. в диапазоне 0..255. */
char filename[12];

void setup() { // THIS RUNS ONCE
  rtc.begin();
//EEPROM.put(0, 20000);
  Setup_timer2();
  Setup_ADC();

  pinMode(10, OUTPUT);
  pinMode(ledStart, OUTPUT);
  pinMode(ledStop, OUTPUT);
  pinMode(btnStop, INPUT_PULLUP);
  pinMode(btnStart, INPUT_PULLUP);

  if (sd.begin(chipSelect, SPI_FULL_SPEED)) { // initialise card on SPI to 8MHz SPI bus speed
    for (int dloop = 0; dloop < 4; dloop++) {
      digitalWrite(ledStart, !digitalRead(ledStart));
      delay(100);
    }
  } else { // if error, flash LED twice per second, until reset
    while (1) {
      digitalWrite(ledStart, !digitalRead(ledStart));
      delay(500);
    }
  }

}

void loop() { // THIS RUNS LOTS!

 if (digitalRead(btnStart) == LOW && recPressed == 0) {
    /* Записываем в RecordNumber, значение из ячейки №0 EEPROM, и прибавляем 1. */
    /*RecordNumber = EEPROM.read(0) + 1;*/
     if (RecordNumber == 32767)RecordNumber = 0;
/*RecordNumber==RecordNumber+1;*/
       EEPROM.get(0,RecordNumber) ;
       /* Записываем в ячейку №0 EEPROM, увеличенное значение RecordNumber. */
    /*EEPROM.write(0, RecordNumber);*/
    EEPROM.put(0, RecordNumber+1);
   String str;  //declaring string.
    //
   str = String(RecordNumber); //converting integer into a string.
   while (str.length() < 6)
    {
    str = "0" + str;
      }
   str.concat(".wav");
   str.toCharArray(filename, sizeof(filename));
    /*str.toCharArray(NameRecord, 4); //passing the value of the string to the character array.*/
    /*SdFile::dateTimeCallback(dateTime);*/
    StartRec(); // launch StartRec method
    timer1on = 0;
  }
  else if (digitalRead(btnStart) == HIGH && recPressed == 1 && timer1on == 0)
    {
      timer1 = millis();
      timer1on = 1;
    }
    else if (digitalRead(btnStart) == LOW && recPressed == 1 && timer1on == 1) {
    timer1on = 0;
    }
   
  else if (digitalRead(btnStart) == HIGH && recPressed == 1 && timer1on == 1 && (millis() - timer1) > 2000)
  {
    StopRec(); // launch StopRec method
   
    /*         Поэтому (Делаем программную перезагрузку). */
    ((void (*)())0x0000)(); /* Делаем программную перезагрузку - Arduino */
  }
 
  if (recByteCount % 1024 == 386 && recPressed == 1) {
    rec.write(buf00, 386);  // save buf01 to card
    recByteSaved += 386;
  }
  if (recByteCount % 1024 == 0 && recPressed == 1) {
    rec.write(buf01, 386);  // save buf02 to card
    recByteSaved += 386;
  }
}

void StartRec() { // begin recording process

  digitalWrite(ledStart, HIGH);
  digitalWrite(ledStop, LOW);
  recByteCount = 0;
  recByteSaved = 0;
  recPressed = 1; // recording button has been pressed
  stopPressed = 0;
  writeWavHeader();
  sbi (TIMSK2, OCIE2A); // enable timer interrupt, start grabbing audio

}

void StopRec() { // stop recording process, update WAV header, close file

  cbi (TIMSK2, OCIE2A); // disable timer interrupt
  writeOutHeader();
  digitalWrite(ledStart, LOW); // turn off recording LED
  digitalWrite(ledStop, HIGH); // light stop LED
  recPressed = 0;

}

void writeOutHeader() { // update WAV header with final filesize/datasize

  rec.seekSet(4);
  byte1 = recByteSaved & 0xff;
  byte2 = (recByteSaved >> 8) & 0xff;
  byte3 = (recByteSaved >> 16) & 0xff;
  byte4 = (recByteSaved >> 24) & 0xff;
  rec.write(byte1);  rec.write(byte2);  rec.write(byte3);  rec.write(byte4);
  rec.seekSet(40);
  rec.write(byte1);  rec.write(byte2);  rec.write(byte3);  rec.write(byte4);
  rec.close();

}

void dateTime(uint16_t* date, uint16_t* time) {
  DateTime now = rtc.now();

  // return date using FAT_DATE macro to format fields
  *date = FAT_DATE(now.year(), now.month(), now.day());

  // return time using FAT_TIME macro to format fields
  *time = FAT_TIME(now.hour(), now.minute(), now.second());
}

void writeWavHeader() { // write out original WAV header to file

  recByteSaved = 0;
  // rec.open("rec00000.wav", O_CREAT | O_TRUNC | O_RDWR);
  /*rec.open(NameRecord, O_CREAT | O_TRUNC | O_RDWR); /* Имя нового - записываемого файла на SD-карту. */
  //DateTime now = rtc.now();
   SdFile::dateTimeCallback(dateTime);
   rec.open(filename, O_CREAT | O_TRUNC | O_RDWR); /* Имя нового - записываемого файла на SD-карту. */
   //rec.timestamp(T_CREATE, now.year(), now.month(), now.day(), now.hour(), now.minute(), now.second());
  rec.write("RIFF");
  byte1 = fileSize & 0xff;
  byte2 = (fileSize >> 8) & 0xff;
  byte3 = (fileSize >> 16) & 0xff;
  byte4 = (fileSize >> 24) & 0xff;
  rec.write(byte1);  rec.write(byte2);  rec.write(byte3);  rec.write(byte4);
  rec.write("WAVE");
  rec.write("fmt ");
  byte1 = waveChunk & 0xff;
  byte2 = (waveChunk >> 8) & 0xff;
  byte3 = (waveChunk >> 16) & 0xff;
  byte4 = (waveChunk >> 24) & 0xff;
  rec.write(byte1);  rec.write(byte2);  rec.write(byte3);  rec.write(byte4);
  byte1 = waveType & 0xff;
  byte2 = (waveType >> 8) & 0xff;
  rec.write(byte1);  rec.write(byte2);
  byte1 = numChannels & 0xff;
  byte2 = (numChannels >> 8) & 0xff;
  rec.write(byte1);  rec.write(byte2);
  byte1 = sampleRate & 0xff;
  byte2 = (sampleRate >> 8) & 0xff;
  byte3 = (sampleRate >> 16) & 0xff;
  byte4 = (sampleRate >> 24) & 0xff;
  rec.write(byte1);  rec.write(byte2);  rec.write(byte3);  rec.write(byte4);
  byte1 = bytesPerSec & 0xff;
  byte2 = (bytesPerSec >> 8) & 0xff;
  byte3 = (bytesPerSec >> 16) & 0xff;
  byte4 = (bytesPerSec >> 24) & 0xff;
  rec.write(byte1);  rec.write(byte2);  rec.write(byte3);  rec.write(byte4);
  byte1 = blockAlign & 0xff;
  byte2 = (blockAlign >> 8) & 0xff;
  rec.write(byte1);  rec.write(byte2);
  byte1 = bitsPerSample & 0xff;
  byte2 = (bitsPerSample >> 8) & 0xff;
  rec.write(byte1);  rec.write(byte2);
  rec.write("data");
  byte1 = dataSize & 0xff;
  byte2 = (dataSize >> 8) & 0xff;
  byte3 = (dataSize >> 16) & 0xff;
  byte4 = (dataSize >> 24) & 0xff;
  rec.write(byte1);  rec.write(byte2);  rec.write(byte3);  rec.write(byte4);

}

void Setup_timer2() {

  TCCR2B = _BV(CS21);  // Timer2 Clock Prescaler to : 8
  TCCR2A = _BV(WGM21); // Interupt frequency  = 16MHz / (8 x 90 + 1) = 22191Hz
  OCR2A = 90; // Compare Match register set to 90

}

void Setup_ADC() {

  ADMUX = 0x61; // set ADC to read pin A5, ADLAR to 1 (left adjust)
  cbi(ADCSRA, ADPS2); // set prescaler to 8 / ADC clock = 2MHz
  sbi(ADCSRA, ADPS1);
  sbi(ADCSRA, ADPS0);
}

ISR(TIMER2_COMPA_vect) {

  sbi(ADCSRA, ADSC); // start ADC sample
  while (bit_is_set(ADCSRA, ADSC)); // wait until ADSC bit goes low = new sample ready
  recByteCount++; // increment sample counter
  bufByteCount++;
  if (bufByteCount == 386 && bufWrite == 0) {
    bufByteCount = 0;
    bufWrite = 1;
  } else if (bufByteCount == 386 & bufWrite == 1) {
    bufByteCount = 0;
    bufWrite = 0;
  }

  if (bufWrite == 0) {
    buf00[bufByteCount] = ADCH;
  }
  if (bufWrite == 1) {
    buf01[bufByteCount] = ADCH;
  }


  //  if (recByteCount % 1024 < 386) { // determine which buffer to store sample into
  //    buf01[recByteCount % 386] = ADCH;
  //  } else {
  //    buf02[recByteCount % 386 ] = ADCH;
  //  }

}