#include <SPI.h>
#include <SD.h>

File myFile;
char buf[80];
byte pos = 0;
byte index = 0;

#define string_length 10
char *strings[string_length]; // an array of pointers to the pieces of the above array after strtok()
char *ptr = NULL;

volatile long Xpoint[5] = {0, 1, 2, 3, 4};
volatile long Zpoint[5] = {5, 6, 7, 8, 9};

// change this to match your SD shield or module;
const int chipSelect = 53;

void setup()
{
  // Open serial communications and wait for port to open:
  Serial.begin(9600);
  while (!Serial)
  {
    ; // wait for serial port to connect. Needed for Leonardo only
  }

  Serial.print("Initializing SD card...");

  if (!SD.begin())
  {
    Serial.println("initialization failed!");
    return;
  }
  Serial.println("initialization done.");

  // open the file. note that only one file can be open at a time,
  // so you have to close this one before opening another.
  myFile = SD.open("position.txt", FILE_WRITE);

  // if the file opened okay, write to it:
  if (myFile)
  {
    String testing = "100, 200, 300, 400, 500, 600, 700, 800, 900, 1000";
    Serial.print("Writing to position.txt...");
    myFile.println(testing);
    // close the file:
    myFile.close();
    Serial.println("done.");
  }
  else
  {
    // if the file didn't open, print an error:
    Serial.println("error opening position.txt");
  }

  // re-open the file for reading:
  myFile = SD.open("position.txt");
  if (myFile)
  {
    Serial.println("position.txt:");

    // read from the file until there's nothing else in it:
    while (myFile.available())
    {
      buf[pos++] = myFile.read();
    }

    for (int i = 0; i < pos; i++)
    {
      Serial.write(buf[i]);
    }
    // close the file:
    myFile.close();
  }
  else
  {
    // if the file didn't open, print an error:
    Serial.println("error opening position.txt");
  }

  for (uint8_t i = 0; i < pos; i++)
  {
    Serial.print(buf[i]);
  }
  Serial.println("");
  delay(3000);

  ptr = strtok(buf, ","); // delimiter
  while (ptr != NULL)
  {
    strings[index] = ptr;
    index++;
    ptr = strtok(NULL, ",");
  }
  // Serial.println(index);
  //  print all the parts
  Serial.println("The Pieces separated by strtok()");
  for (int n = 0; n < index; n++)
  {
    Serial.print(n);
    Serial.print("  ");
    Serial.println(strings[n]);
  }
}

void loop()
{
  
  // Those values are Sunlight,Humidity,Temperature,Pressure,Dewpoint.
  // use the atoi() and atof() functions to convert ASCII strings to numbers.

  uint8_t bobo1 = 0, bobo2 = 0;
  for (int n = 0; n < index; n++)
  {
    if (n%2){
      Zpoint[bobo1] = atoi(strings[n]);
      bobo1 ++;
    }
    else{
      Xpoint[bobo2] = atoi(strings[n]);
      bobo2 ++;
    }
  }

  for (uint8_t i = 0; i < 5; i++)
  {
    Serial.print(Xpoint[i]);
    Serial.print(" , ");
    Serial.print(Zpoint[i]);
    Serial.println("");
  }

  delay(3000);
}