/*
  16 bit Shift Register Demo
*/

#include "Seg_LUT.h"

// pin definitions
const int CLOCK_PIN = 4;
const int LATCH_PIN = 3;
const int DATA_PIN  = 2;
const int MAX_DIGITS = 8;

const byte NUM_CHARS = 9; // 8 + nul

char receivedChars[NUM_CHARS];   // an array to store the received data
char fixedChars[NUM_CHARS] = {36, 36, 36, 36, 36, 36, 36, 36};
boolean newData = false;
int msgLen = 0;

void recvWithEndMarker() {
  static byte ndx = 0;
  char endMarker = '\n';
  char rc;

  while (Serial.available() > 0 && newData == false) {
    rc = Serial.read();
    if (rc != endMarker) {
      receivedChars[ndx] = rc;
      ndx++;
      if (ndx >= NUM_CHARS) {
        ndx = NUM_CHARS - 1;
      }
    } else {
      receivedChars[ndx] = '\0'; // terminate the string
      msgLen = ndx;
      ndx = 0;
      newData = true;
    }
  }
}

void showNewData() {
  if (newData == true) {
    Serial.print("This just in ... ");
    Serial.println(receivedChars);
    for (int i = 0; i < msgLen; i++)  {
      char upperCaseChar = toupper(receivedChars[i]) - 55;
      fixedChars[i] = upperCaseChar;

    }
    //sevseg.setChars(receivedChars);
    newData = false;
  }
}

void updateDisplay(uint32_t value, uint8_t dpPos)  {
  uint8_t digitVal;
  uint8_t powOfTen = MAX_DIGITS - 1;
  uint32_t op1 = 1, op2 = 1;

  for (uint8_t digit = 0; digit < powOfTen; digit++) {
    for (uint8_t p = powOfTen - digit; p >= 1; p--) {
      op1 = op1 * 10;
    }
    op2 = op1 * 10;
    // with leading zero blanking (10 is a blank char)
    digitVal = value < op1 ? 10 : (value % op2) / op1;
    // no blanking (better for clocks)
    //digitVal = (value % op2) / op1;
    // fixed decimal point
    writeShiftDigit(digit, digitVal, ((dpPos - 1) == digit) ? true : false);
    // "clock" decimal points
    //writeShiftDigit(digit, digitVal, (digit == 3 || digit == 5) ? true : false);
    op1 = 1; op2 = 1;
  }
  // last digit is never blanked or "dotted"
  writeShiftDigit(powOfTen, value % 10, false);
}

void writeShiftDigit(uint8_t digit, uint8_t charCode, bool dp)  {
  uint8_t value = ~digitCodeMap[charCode]; // invert (~) bits for common anode
  digitalWrite(LATCH_PIN, LOW);
  shiftOut(DATA_PIN, CLOCK_PIN, MSBFIRST, dp ? (value & 0x7f) : value); // OR with 0x80 for common cathode
  shiftOut(DATA_PIN, CLOCK_PIN, MSBFIRST, (1 << digit)); // invert bits (~) for common cathode
  digitalWrite(LATCH_PIN, HIGH);
}

void setup() {
  Serial.begin(115200);
  pinMode(DATA_PIN, OUTPUT);
  pinMode(CLOCK_PIN, OUTPUT);
  pinMode(LATCH_PIN, OUTPUT);
}

void loop() {

  updateDisplay(12345678UL, 6);

/*
  recvWithEndMarker();
  showNewData();

  for (int i = 0; i <= NUM_CHARS; i++) {
       writeShiftDigit(i, fixedChars[i], false);
       //Serial.println(upperCaseChar);
  }
*/
  /*
  for (int digit = 0; digit < 8; digit++)  {
    for (int j = 0; j < 42; j++)  {

      //writeShiftValue(1 << i);
      writeShiftDigit(digit, j, false);
      delay(500);
    }
    delay(500);
  }
  */
  //writeShiftValue(0xAAAA);
  //delay(1000);
  //writeShiftValue(0x5555);
  //delay(1000);
}