//custom letter and symbol libary
#include "symbols.h"
//ASCII ARRAY user input that has been converted to ASCII
int   ASCIIArray[20];
//Declare pins
int cols[8] = {22,24,26,28,30,32,34,36};
int rows[8] = {23,25,27,29,31,33,35,37};

//EEPROM lib
#include <EEPROM.h>

String inputString = "Edmund";  //inpuiitstring used in serial event, placeholder for led
bool sendit = true;   //determines if user pressed enter during serial event

//interrrupt button
#include "OneButton.h"

#define PIN_INPUT 3
OneButton button(PIN_INPUT, true);

// save the millis when a press has started.
unsigned long pressStartTime;

int presslength; //time that is button pressed
int direction = 0; //0 is right to left, 1 is left to right


void setup() {
  Serial.begin(115200);

  Serial.println("Enter New text via serial. (Max 20, Leters only)");

  //defines the pin modes for the led array
  for (int i = 0; i < 8; i++) {
    pinMode(cols[i], OUTPUT);
    pinMode(rows[i], OUTPUT);
  }
  ledreset();

  attachInterrupt(digitalPinToInterrupt(PIN_INPUT), checkTicks, CHANGE);
  button.attachClick(singleClick);
  button.attachDoubleClick(doubleClick);

  button.setPressTicks(800); // time until longpress
  button.attachLongPressStart(pressStart);
  button.attachLongPressStop(pressStop);
}

void loop() {
  getInput(); //emprom inside
  read4eeprom();  //updates ascii with eeprom
  if (direction == 0) {
    RightToLeft(50);
  } else {
    LeftToRight(50);
  }
}

//write to eeprom
void write2eeprom() {
  for (int i = 0; i < 20; i++) {
    EEPROM.write(i, 255);   //resets eeprom - moveed outside of if as eeprom would remember non-over written vars
    if (ASCIIArray[i]) {          //eg first msg "edmund" second msg "cake", result "cakend"
      EEPROM.write(i, ASCIIArray[i]);   //write eeprom address
    }
  }
}

//read from eeprom
void read4eeprom() {
  for (int i = 0; i < 20; i++) {
    if (EEPROM.read(i) != 255) {      //skips assignment of value if read value is 255 (empty)
      ASCIIArray[i] = EEPROM.read(i); //without the skip the display wont cycle back
    }
  }
}

//scrolling text function Right 2 left
void RightToLeft(int speed) {
  int loopcycle;    //loop cycle is used in speed setting
  int cycle = 14;   //starting point for the first letter
  int letter1   = ASCIIArray[0] - 65; //ascii array contains ascii, we - 65 to get bitmap equivatlent 0 = a, 1 = b
  int letter2   = ASCIIArray[1] - 65;
  int add1 = 1; //counter cycle for each passed letter
  while (1) {
    button.tick();
    // % speed determines the times that the cycle is true. This sets speed, lower = faster
    if (loopcycle % speed == 0) { 
      //changes position of the display by 2  
      cycle = cycle - 2;
    }
      //when we have counted the number of letters in input + 1 we reset the text and add1 var
    if (add1 == getASCIIcount() + 1) {
      add1 = 1;
      letter1   = ASCIIArray[0] - 65;
      letter2   = ASCIIArray[1] - 65;
    }
      //when text is off screen 2nd display becomes 3rd. 1st display becomes 2nd
    if (cycle == -14) {
          //end of cycle
          add1 = add1 + 1;
          letter1   = letter2;
          letter2   = ASCIIArray[add1] - 65;
  //Serial.println(add1);
          cycle = 0;
          if (add1 == getASCIIcount() + 1) {  //instead of cycle position 0 we goto 14 when reseting text, prevents letter in middle
            break;                       //break added so the while loop ends after a single message
          }
          loopcycle++;
    }
    printletter(letter1, cycle);
    printletter(letter2, cycle + 14);
    loopcycle++;
  }
}

//Scrolling text function left 2 right
void LeftToRight(int speed) {
  int loopcycle;    //loop cycle is used in speed setting
  int cycle = 0;   //starting point for the first letter
  int letter1   = ASCIIArray[getASCIIcount()] - 65; //ascii array contains ascii, we - 65 to get bitmap equivatlent 0 = a, 1 = b
  int letter2   = ASCIIArray[getASCIIcount()-1] - 65;
  int add1 = getASCIIcount()-1; //counter cycle for each passed letter
  while (1) {
    button.tick();
    //Serial.println(cycle);
    // % speed determines the times that the cycle is true. This sets speed, lower = faster
    if (loopcycle % speed == 0) { 
      //changes position of the display by 2  
      cycle = cycle + 2;
    }
      //when we have counted the number of letters in input + 1 we reset the text and add1 var
    if (add1 == -getASCIIcount()) {
      add1 = getASCIIcount()-1;
      letter1   = ASCIIArray[getASCIIcount()] - 65;
      letter2   = ASCIIArray[getASCIIcount()-1] - 65;
    }
      //when text is off screen 2nd display becomes 3rd. 1st display becomes 2nd
    if (cycle == 14) {
          //end of cycle
          add1 = add1 - 1;
          letter1   = letter2;
          letter2   = ASCIIArray[add1] - 65;
          cycle = 0;
          //Serial.println(add1);
          if (add1 == -2) {  //instead of cycle position 0 we goto 14 when reseting text, prevents letter in middle
            break;                       //break added so the while loop ends after a single message
          }
          loopcycle++;
    }
    printletter(letter1, cycle);
    printletter(letter2, cycle - 14);
    loopcycle++;
  }
}

// display function, letter is the number corresponding to the 3d bitmap array and offset is the position of display
void printletter(int letter, int offset) {
  for (int i = 0; i < 8; i++) {             //Loops cycle through for each letter
    for (int j = 0; j < 8; j++){
      //int readbyte = a[i][j];
      int readbyte = symbols[letter][i][j];
      digitalWrite(rows[i],HIGH);
      digitalWrite(cols[j] + offset,!readbyte);
    }
    ledreset();
  }
}

//function to find the length of actual text to display
int getASCIIcount() {
  int count = 0;
  for (int cc = 0; cc < 20; cc++) {
    if (ASCIIArray[cc] != 0) {
    count++;
    }
  }
  return count;
}

//reset leds
void ledreset() {
  for (int i = 0; i < 8; i++) {
    digitalWrite(cols[i], HIGH);
    digitalWrite(rows[i], LOW);
    }
}

void getInput() {
  String input;
  char  INarray[20];

  if (sendit == true) {
    sendit = false;
    input = inputString;
    input.toUpperCase();
    inputString = "";

    for (int j = 0; j < 20; j++) {
    ASCIIArray[j] = 0;
    INarray[j] = 0;
  }
      //convert string to char array, +1 to the length at it starts from 0
  input.toCharArray(INarray, input.length() + 1);
    //char to ascii conversion, +48 is used to bump it up to the expected values
  for (int i = 0; i < 20; i++) {
    if (isAlpha(INarray[i])) {      //isAlpha check required as unknown vars are appended to ascii array
      ASCIIArray[i] = (INarray[i] - '0') + 48;
      //Serial.println(i);
    } else {
      ASCIIArray[i] = 0;
    }
  }
  write2eeprom(); //writes new msg to eeprom
  }
}

void serialEvent() {
  while (Serial.available()) {
    // get the new byte:
    char key = (char)Serial.read();
    // if the incoming character is a newline, set a flag so the main loop can
    // do something about it:
    if (key == '\n') {
    sendit = true;
    Serial.println(inputString);
    }
    if (isAlpha(key)) {
      if (inputString.length() < 20) {  //prevents not alpha and too long inputs
      inputString += key;
      }
    }
  }
}

//debug - tests all leds
void dotcycle() {
  for (int i = 0; i < 8; i++) {
    for (int j = 0; j < 8; j++){
      ledreset();
      digitalWrite(rows[i],HIGH);
      digitalWrite(cols[j],LOW);
      delay(50);
    }
  }
}

void checkTicks() {
  button.tick();
}

void singleClick() {
  
} // singleClick

void doubleClick() {
  
}

void pressStart() {
  pressStartTime = millis() - 800; // as set in setPressTicks()
}
// function called after long press
void pressStop() {
  presslength = millis() - pressStartTime;
  Serial.print("Button Pressed for:"); Serial.println(presslength);
  if (presslength >= 800 && presslength <= 1200) {
    //right 2 left
    direction = 0;
  } else if (presslength >= 1800 && presslength <= 2200) {
    //left 2 right
    direction = 1;
  } else {
    direction = direction;
    //stay
  }
}