#include "atoz.h" // external library containing arrays for all the letters

// defining the column pins
#define C1 15
#define C2 16
#define C3 17
#define C4 18
#define C5 2
#define C6 3
#define C7 4
#define C8 5
// defining the row pins
#define R1 13
#define R2 12
#define R3 11
#define R4 10
#define R5 9
#define R6 8
#define R7 7
#define R8 6



void setup() {

  Serial.begin(9600);
  pinMode(21, INPUT);
  Serial.println("Type in String.");
  Serial.println("This is your text:");
  for (int i = 2; i < 19; i++) { // for loop to set pins 2-19 as output and set to LOW
    pinMode(i, OUTPUT);
    digitalWrite(i, LOW);
  }
  for (int j = 6; j < 14; j++) { // for loop to set pin 6-14 as HIGH
    digitalWrite(j, HIGH);
  }
}
// Function to select rows
void SelectRow(int row) {
  if (row == 1) digitalWrite(R1, LOW); else digitalWrite(R1, HIGH);
  if (row == 2) digitalWrite(R2, LOW); else digitalWrite(R2, HIGH);
  if (row == 3) digitalWrite(R3, LOW); else digitalWrite(R3, HIGH);
  if (row == 4) digitalWrite(R4, LOW); else digitalWrite(R4, HIGH);
  if (row == 5) digitalWrite(R5, LOW); else digitalWrite(R5, HIGH);
  if (row == 6) digitalWrite(R6, LOW); else digitalWrite(R6, HIGH);
  if (row == 7) digitalWrite(R7, LOW); else digitalWrite(R7, HIGH);
  if (row == 8) digitalWrite(R8, LOW); else digitalWrite(R8, HIGH); // if said row is selected write it on LOW otherwise set to HIGH
}

void Select_Columns(int column, int state) {
  if (column == 1) digitalWrite(C1, state); // once row is picked it will cycle through the columns
  if (column == 2) digitalWrite(C2, state); // if that columns value is on it will turn on the LED
  if (column == 3) digitalWrite(C3, state); // the state variable checks if the value is 0 or 1
  if (column == 4) digitalWrite(C4, state);
  if (column == 5) digitalWrite(C5, state);
  if (column == 6) digitalWrite(C6, state);
  if (column == 7) digitalWrite(C7, state);
  if (column == 8) digitalWrite(C8, state);
}

String inp;
String inpUpper;
int position = 0;

void loop() {
  delay(1500);
  int butread = digitalRead(21); // reads the button whether its pressed or not

  while (Serial.available() > 0) {
    inp = Serial.readStringUntil('\n');
    inp.toUpperCase();// converts all input into upper case

  }

  int inputlen = inp.length(); // the length of the input 

  // first if statement that would run when the button is not pressed
  // under this the letters scroll from right to left 
  if (butread == 0) {
    for (int i = 0; i < inputlen; i++) { // for loop to iterate through all the letter in the input 
      //Serial.print(inp.charAt(i)); // prints the individual letters on serial monitor
      switch (inp.charAt(i)) { // switch statement that iterates for every letter entered

        case ' ': // accounting for spaces in input 
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, blank[j][(i + position) - abs((i + position) / 16) * 16]);

              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
        break;

        // following are the case statements for each letter
        // Set_LED_in_Acitve_Row function's second parameter makes it so that the leds moved over by 1 to the left
        // thus creating a scrolling effect
        // for each iteration it moves it to one position to the right

        case 'A':
          for (int x = 0; x < 15; x++) { // for loop to set the speed of the scroll
            for (int j = 0; j < 8; j++) { // loop to iterate through the rows
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) { // calls the column function 
                Select_Columns(i + 1, A[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1; // position increments by 1 for each interation 
            delay(10);
          }
          break;

        case 'B':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, B[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'C':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, C[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'D':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, D[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'E':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, E[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'F':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, F[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'G':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, G[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'H':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, H[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'I':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, I[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'J':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, J[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'K':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, K[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'L':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, L[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'M':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, M[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'N':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, N[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'O':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, O[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'P':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, P[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'Q':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, Q[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'R':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, R[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'S':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, S[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'T':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, T[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'U':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, U[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'V':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, V[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'X':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, X[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'Y':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, Y[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;

        case 'Z':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 0; i < 8; i++) {
                Select_Columns(i + 1, Z[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position + 1;
            delay(10);
          }
          break;
      }
    }

  }
  // next else if statement runs when button is pressed
  // under this the letters scroll from left to right
  else if (butread == 1) {
    for (int i = 0; i < inputlen; i++) {
      Serial.print(inp.charAt(i));
      // starts the position from the other side of the led matrix
      // by default postion = 0 is on the right side 
      position = 8; // starts from the left
      switch (inp.charAt(i)) {
        case ' ':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) { // reverses the order through which the for loop iterates through the columns
                Select_Columns(i + 1, blank[j][(i + position) - abs((i + position) / 16) * 16]);

              }
              delay(10);
            }
            position = position - 1; // position decrements by 1 for each iterations
            delay(10);
          }
          break;

        case 'A':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, A[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'B':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, B[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'C':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, C[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'D':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, D[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'E':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, E[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'F':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, F[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'G':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, G[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'H':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, H[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'I':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, I[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'J':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, J[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'K':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, K[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'L':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, L[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'M':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, M[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'N':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, N[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'O':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, O[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'P':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, P[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'Q':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, Q[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'R':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, R[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'S':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, S[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'T':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, T[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'U':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, U[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'V':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, V[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'X':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, X[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'Y':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, Y[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;

        case 'Z':
          for (int x = 0; x < 15; x++) {
            for (int j = 0; j < 8; j++) {
              SelectRow(j + 1);
              for (int i = 8 ; i > 0; i--) {
                Select_Columns(i + 1, Z[j][(i + position) - abs((i + position) / 16) * 16]);
              }
              delay(10);
            }
            position = position - 1;
            delay(10);
          }
          break;
      }
    }
  }
}