#include <GyverTimers.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

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

// declare an SSD1306 display object connected to I2C
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

//unsigned long startMillis;  //some global variables available anywhere in the program
//unsigned long currentMillis;
//const unsigned long period = 1000;  //the value is a number of milliseconds

float vbus = 0.0;
float current = 0.0;
float as = 0.0;
float ah = 0.0;
float ws = 0.0;
float wh = 0.0;

int upbutton = HIGH;
int downbutton;
int leftbutton;
int rightbutton;
int exebutton;

int vertical = 0;
int horizontal = 0;

String name = "Trigger";
String version = " v1";


void setup()
{
  Serial.begin(9600);
  Timer1.setFrequency(10); 
  Timer1.enableISR();
  // initialize OLED display with address 0x3C for 128x64
  if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    while (true);
  }
  oled.clearDisplay();
  //startMillis = millis();

  pinMode(13, INPUT_PULLUP);//UP
  pinMode(12, INPUT_PULLUP);//DOWN
  pinMode(11, INPUT_PULLUP);//LEFT
  pinMode(10, INPUT_PULLUP);//RIGHT
  pinMode(9, INPUT_PULLUP);//EXECUTE

  pinMode(8, OUTPUT);digitalWrite(8, LOW);//POWER ENABLE
  delay(500);
  pinMode(7, OUTPUT);digitalWrite(7, LOW);//18V
  pinMode(6, OUTPUT);digitalWrite(6, LOW);//15V
  pinMode(5, OUTPUT);digitalWrite(5, LOW);//12V
  pinMode(4, OUTPUT);digitalWrite(4, HIGH);//9V
  pinMode(3, OUTPUT);digitalWrite(3, LOW);//5V
  //oled.begin(SSD1306_SWITCHCAPVCC, 0x3D); //or 0x3C
}


void loop()
{
  upbutton = digitalRead(13);
  downbutton = digitalRead(12);
  leftbutton = digitalRead(11);
  rightbutton = digitalRead(10);
  exebutton = digitalRead(9);

  optionselect();
  execution();
  //displaypage();
}

void optionselect(){
  if(upbutton == LOW){
    delay(200);
    vertical--;
    if(vertical < 0) vertical = 4;
  }
  if(downbutton == LOW){
    delay(200);
    vertical++;
    if(vertical > 4) vertical = 0;
  }
  if(leftbutton == LOW){
    delay(200);
    horizontal--;
    if(horizontal < 0) horizontal = -1;
  }
  if(rightbutton == LOW){
    delay(200);
    horizontal++;
    if(horizontal > 1) horizontal = 1;
  }
  displaypage();
}

void execution(){
  if(exebutton == LOW){
    //digitalWrite(8, LOW);
    displaypage();
    delay(200);
    if(vertical == 0){
      digitalWrite(7, LOW);//18V
      digitalWrite(6, LOW);//15V
      digitalWrite(5, LOW);//12V
      digitalWrite(4, HIGH);//9V Enable
      digitalWrite(3, LOW);//5V
    }
    else if(vertical == 1){
      digitalWrite(7, LOW);//18V
      digitalWrite(6, LOW);//15V
      digitalWrite(5, HIGH);//12V Enable
      digitalWrite(4, LOW);//9V
      digitalWrite(3, LOW);//5V
    }
    else if(vertical == 2){
      digitalWrite(7, LOW);//18V
      digitalWrite(6, HIGH);//15V Enable
      digitalWrite(5, LOW);//12V
      digitalWrite(4, LOW);//9V
      digitalWrite(3, LOW);//5V
    }
    else if(vertical == 3){
      digitalWrite(7, HIGH);//18V Enable
      digitalWrite(6, LOW);//15V
      digitalWrite(5, LOW);//12V
      digitalWrite(4, LOW);//9V
      digitalWrite(3, LOW);//5V
    }
    else if(vertical == 4){
      //20V Enable
      digitalWrite(7, LOW);//18V
      digitalWrite(6, LOW);//15V
      digitalWrite(5, LOW);//12V
      digitalWrite(4, LOW);//9V
      digitalWrite(3, LOW);//5V
    }
    displaypage();
  }
  displaypage();
}

void displaypage(){
  if(horizontal == 0)  mainpage();
  else if(horizontal == 1) meterpage();
  else if(horizontal == -1) manualpage();
}

void manualpage(){
  oled.clearDisplay();
  oled.setTextSize(1); 
  oled.setTextColor(WHITE, BLACK);
  oled.setCursor(0, 0);
  
  oled.println("INSTRUCTION      v1.0");
  printline();
  nextline(0, 10);
  oled.print("1.Left/Right: Display");
  nextline(0, 10);
  oled.print("2.Up/Down   : Voltage");
  nextline(0, 10);
  oled.print("3.Centre    : Confirm");
  nextline(0, 15);
  oled.print("Designed by Sober Lam");
  oled.display();
}

void mainpage(){
  oled.clearDisplay();
 //delay(200);
  oled.setTextSize(1); 
  oled.setTextColor(WHITE, BLACK);
  oled.setCursor(0, 0);
  //if(vertical == 0) arrow();
  //oled.print(pdv,3);
  displayreading();

  oled.setTextSize(4); 
  if(vertical == 0) oledDisplayCenter("9 V");
  else if(vertical == 1) oledDisplayCenter("12 V");
  else if(vertical == 2) oledDisplayCenter("15 V");
  else if(vertical == 3) oledDisplayCenter("18 V");
  else if(vertical == 4) oledDisplayCenter("20 V");

  oled.display();
}

void meterpage(){
  oled.clearDisplay();

  oled.setTextSize(3);
  oled.setTextColor(WHITE, BLACK);
  oled.setCursor(8, 8);
  if(vbus < 10){
    String v1 = "";
    v1.concat(" ");
    v1.concat(vbus);
    oled.print(v1);
  }
  else oled.print(vbus);
  oled.setCursor(103, oled.getCursorY());
  oled.print("V");

  oled.setCursor(8, 33);
  String displayc = "";
  displayc.concat(" ");
  displayc.concat(current);
  oled.print(displayc);
  oled.setCursor(103, oled.getCursorY());
  oled.print("A");

  oled.display();
}

/*void clearOLEDLine(int row){
  
  for (int y=row; y<=row+6; y++){
    for (int x=0; x<127; x++){
      oled.drawPixel(x, y, BLACK); 
      }
  }
  //lcd.setCursor(0,line);
}*/

void displayreading(){
  oled.setTextSize(1); 
  //oled.setCursor(80, 10);
  
  if(vbus < 1) oled.print("DISCONNECTED");
  else oled.print("CONNECTED");
  
  oled.setCursor(85, 0);
  if(vbus < 10){
    String v1 = "";
    v1.concat(" ");
    v1.concat(vbus);
    oled.print(v1);
  }
  else oled.print(vbus);
  oled.setCursor(117, oled.getCursorY());
  oled.print("V");

  /*nextline(80, 10);
  String displayc1 = "";
  displayc1.concat(" ");
  displayc1.concat(current);
  oled.print(displayc1);
  oled.setCursor(115, oled.getCursorY());
  oled.print("A");*/
  
}



void printline(){
  for (int y = oled.getCursorY(); y<= oled.getCursorY(); y++){
    for (int x=0; x<127; x++){
      oled.drawPixel(x, y, WHITE); 
      }
  }
}

void nextline(int x, int yoffset){
  oled.setCursor(x, oled.getCursorY()+yoffset);
}

void arrow(){
  oled.setCursor(30, oled.getCursorY());
  oled.print(" <<-");
  //oled.invertDisplay(true);
}

void oledDisplayCenter(String text) {
  int16_t x1;
  int16_t y1;
  uint16_t width;
  uint16_t height;
  oled.setTextColor(WHITE, BLACK);
  //oled.setTextSize(2);
  oled.getTextBounds(text, 0, 0, &x1, &y1, &width, &height);

  oled.setCursor((SCREEN_WIDTH - width) / 2, (SCREEN_HEIGHT - height) / 2);
  oled.print(text); // text to display
  //oled.display();
}

ISR(TIMER1_A) {
  // float analogvalue = analogRead(A0);
  // float analogvalue1 = analogRead(A1);
  // float analogvalue2 = analogRead(A2);
  // float analogvalue3 = analogRead(A3);
  vbus = ((analogRead(A0) * 5.0) / 1024) / 0.24;// ~24K/99K
  vbus = (vbus * 4.8) / 5;// VUSB tune
  if(vbus < 4) vbus = 0;
  
  //current = (analogRead(A2) * 5.0) / 1024;
  for (int i = 0; i < 10; i++){
    current = current + (analogRead(A2) * 5.0) / 1024;;
  }
  current = (current * 4.8) / 50;
  current = (2.5 - current) / 0.49;
  if(current < 0.2) current = 0;
  else if(current > 2.3) current = 0;

  as = current / 36000;
  ah = ah + as;

  ws = (vbus * current) / 36000;
  wh = wh + ws;

  if(vbus < 4){
    ah = 0;
    wh = 0;
  }
  //pdv = analogvalue / 0.4152; //
  //Serial.println(ah,3);
  //Serial.println(wh,3);
}