#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <elapsedMillis.h>
#include <EEPROM.h>
#include "variables.h"

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
// #define OLED_RESET 4 // Reset pin # (or -1 if sharing Arduino reset pin)
#define OLED_RESET -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3D ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

///////////////////////////
// Create Clocks + Timeout Timers
/////////////////////////
elapsedMicros clock0Timer;
elapsedMicros clock1Timer;
elapsedMicros clock2Timer;
elapsedMicros clock3Timer;

elapsedMicros resetOutTimer;

elapsedMicros timeoutTimer;

elapsedMicros freerunTimer;

void setup() {
  Serial.begin(115200);
  Serial.println("=====================");
  Serial.println("     Rusty Valve     ");
  Serial.println("=====================");
  Serial.println("QUAD Clock Sequencer ");
  Serial.println("=====================");

  // get the savedSpaces array from EEPROM
  //EEPROM.get(0, savedSpaces);

  // initialise pins and interrupts
  setPinModes();
  setHardwareInterrupts();

  // initialise arrays
  preFill();

  calcEuclideanGates(0);
  calcEuclideanGates(1);
  calcEuclideanGates(2);
  calcEuclideanGates(3);

  calcClock(0);
  calcClock(1);
  calcClock(2);
  calcClock(3);

  // initialise the display
  initialiseDisplay();
  // updateDisplay();

  resetClock0();
  resetClock1();
  resetClock2();
  resetClock3();

  updateDisplay();
}

///////////////////////////
// Set Pin Modes
///////////////////////////
void setPinModes() {
  // pinMode(upButtPin, INPUT);
  // pinMode(downButtPin, INPUT);
  // pinMode(leftButtPin, INPUT);
  // pinMode(rightButtPin, INPUT);

  // pinMode(encAPin, INPUT);
  // pinMode(encBPin, INPUT);
  // pinMode(encButtPin, INPUT);

  // pinMode(clockSelectButtPin, INPUT);
  // pinMode(pageSelectButtPin, INPUT);
  // pinMode(clockResetButtPin, INPUT);

  // pinMode(clockResetPin, INPUT);

  pinMode(clock0Pin, OUTPUT);
  pinMode(clock1Pin, OUTPUT);
  pinMode(clock2Pin, OUTPUT);
  pinMode(clock3Pin, OUTPUT);

  pinMode(resetOutPin, OUTPUT);

  ///////////////////////////
  // Set initial pin states
  ///////////////////////////
  digitalWrite(clock0Pin, LOW);
  digitalWrite(clock1Pin, LOW);
  digitalWrite(clock2Pin, LOW);
  digitalWrite(clock3Pin, LOW);

  digitalWrite(resetOutPin, LOW);
}

///////////////////////////
// Set hardware interrupts on input pins
///////////////////////////
void setHardwareInterrupts() {
  // attachInterrupt(digitalPinToInterrupt(upButtPin), upButtDOWN, RISING);
  // attachInterrupt(digitalPinToInterrupt(downButtPin), downButtDOWN, RISING);
  // attachInterrupt(digitalPinToInterrupt(leftButtPin), leftButtDOWN, RISING);
  // attachInterrupt(digitalPinToInterrupt(rightButtPin), rightButtDOWN, RISING);

  // attachInterrupt(digitalPinToInterrupt(encAPin), encARotated, RISING);
  // attachInterrupt(digitalPinToInterrupt(encButtPin), encButtDOWN, RISING);

  // attachInterrupt(digitalPinToInterrupt(clockSelectButtPin), clockSelectButtDOWN, RISING);
  // attachInterrupt(digitalPinToInterrupt(pageSelectButtPin), pageSelectButtDOWN, RISING);
  // attachInterrupt(digitalPinToInterrupt(clockResetButtPin), clockResetButtDOWN, RISING);

  // attachInterrupt(digitalPinToInterrupt(clockResetPin), clockResetEXT, RISING);
}

///////////////////////////
// pre-fill the euclidGate, manualGate and manualSwing arrays with initial values of 1, 1 and 43 respectively
///////////////////////////
void preFill() {
  for (uint8_t i = 0; i < 4; i++) {
    for (uint8_t j = 0; j < MAX_STEPS + 1; j++) {
      euclidGate[i][j] = 1;
      manualGate[i][j] = 1;
      manualSwing[i][j] = 43;
    }
  }
}

///////////////////////////
// Initialise display
///////////////////////////
void initialiseDisplay() {
  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  if(!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }

  // Clear the buffer
  display.clearDisplay();
 
  display.drawRect(0, 0, display.width(), display.height(), SSD1306_WHITE);
 
  display.setTextSize(2);      // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE); // Draw white text
  display.cp437(true);         // Use full 256 char 'Code Page 437' font
 
  // display the intro text
  display.setCursor(5, 4);
  display.print("Rusty");
  display.setCursor(40, 19);
  display.print("Valve");

  display.setTextSize(1);
  display.setCursor(5, 43);
  display.print("QUAD");
  display.setCursor(5, 53);
  display.print("Clock Sequencer");

  // update the display and delay by 5 seconds
  display.display();
  delay(500);
}

void loop() {
  // check Clock 0 to see if it should be updated
  if (clock0Timer >= stepHalfTime[0][currentStep[0]]) {
    clockAction(0);
  }

  // check Clock 1 to see if it should be updated
  if (clock1Timer >= stepHalfTime[1][currentStep[1]]) {
    clockAction(1);
  }

  // check Clock 2 to see if it should be updated
  if (clock2Timer >= stepHalfTime[2][currentStep[2]]) {
    clockAction(2);
  }

  // check Clock 3 to see if it should be updated
  if (clock3Timer >= stepHalfTime[3][currentStep[3]]) {
    clockAction(3);
  }

  // check resetOutTimer to see if the pin should be set to LOW
  if (resetOutTimerON == 1) {
    if (resetOutTimer >= resetOutTimerTIME) {
      digitalWrite(resetOutPin, LOW);
      resetOutTimerON = 0;
      // Serial.println("EXTERNAL reset turned OFF ");
    }
  }

  // check timeoutTimer to see if screen should be turned off
  if (timeOutOn == 1 && screenTimedOut == 0) {
    if (timeoutTimer >= timeoutMicros[timeoutTime]) {
      screenTimedOut = 1;
      clearDisplay();
    }
  }

  ///////////////////////////
  // receive commands over serial
  ///////////////////////////
  if (Serial.available()) { // if there is data coming
    String command = Serial.readStringUntil('\n'); // read string until newline character
    
    if (command == "w") {
      Serial.println("UP");
      upButtDOWN();
    }
    if (command == "s") {
      Serial.println("DOWN");
      downButtDOWN();
    }
    if (command == "a") {
      Serial.println("LEFT");
      leftButtDOWN();
    }
    if (command == "d") {
      Serial.println("RIGHT");
      rightButtDOWN();
    }
    if (command == ".") {
      Serial.println("ENCODER Rotate CW");
      encARotated(1);
    }
    if (command == ",") {
      Serial.println("ENCODER Rotate CCW");
      encARotated(-1);
    }
    if (command == "/") {
      Serial.println("ENCODER Button PRESSED");
      encButtDOWN();
    }
    if (command == "c") {
      Serial.println("CLOCK Button PRESSED");
      clockSelectButtDOWN();
    }
    if (command == "p") {
      Serial.println("PAGE Button PRESSED");
      pageSelectButtDOWN();
    }
    if (command == "r") {
      Serial.println("RESET Button PRESSED");
      clockResetButtDOWN();
    }
    if (command == "e") {
      Serial.println("EXTERNAL RESET Received");
      clockResetEXT();
    }
  }
}