#include <SPI.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

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET     4 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

uint8_t ball_x = 64, ball_y = 32;
uint8_t scoreLeft = 0;
uint8_t scoreRight = 0;
int16_t paddleNumLeft = 32;
int16_t paddleNumRight = 32;
bool horizontal = false;
bool vertical = false;
bool win = false;
String winner;

int16_t paddleNum = 32;
int16_t cpuPaddleNum = 32;

void drawCourt(){
  display.drawRect(0, 0, 128, 64, WHITE);
}

void setup() {
  // put your setup code here, to run once:
  pinMode(2, INPUT);
  pinMode(3, INPUT);
  pinMode(6, INPUT);
  pinMode(5, INPUT);

  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);

}
void displayScoreLeft() {
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(2,2);
  display.print(scoreLeft);
}

void displayScoreRight() {
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(118,2);
  display.print(scoreRight);
}

void displayWin() {
  display.setTextSize(2);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(15,15);
  display.print(winner); 
}

void loop() {
  start1PlayerGame();
  // display.clearDisplay();
  // display.setTextSize(1);
  // display.setTextColor(SSD1306_WHITE);
  // display.setCursor(20, 10);
  // display.println("Choose mode:");
  // display.setCursor(35, 30);
  // display.println("1 Player");
  // display.setCursor(35, 40);
  // display.println("2 Players");
  // display.display();
}

void ballRight() {
  display.drawPixel(ball_x, ball_y, WHITE);
  ball_x += 1;

}
void ballLeft() {
  display.drawPixel(ball_x, ball_y, WHITE);
  ball_x -= 1;
}

void ballDown() {
  display.drawPixel(ball_x, ball_y, WHITE);
  ball_y += 1;
}

void ballUp() {
  display.drawPixel(ball_x, ball_y, WHITE);
  ball_y -= 1;
}

void leftPaddle() {
  // x, y, h, color
 display.drawFastVLine(10, paddleNumLeft, 20, WHITE);
}

void rightPaddle() {
  // x, y, h, color
 display.drawFastVLine(115, paddleNumRight, 20, WHITE);
}

void paddle() {
  // x, y, h, color
 display.drawFastVLine(10, paddleNum, 20, WHITE);
}

void cpuPaddle() {
  // x, y, h, color
 display.drawFastVLine(115, cpuPaddleNum, 20, WHITE);
}


void start1PlayerGame() {
  // Your logic for the 1 player game goes here
  // This function should handle the game mechanics for 1 player mode
  uint8_t ball_x = 64, ball_y = 32;
  uint8_t score = 0;

  bool horizontal = false;
  bool vertical = false;
  bool win = false;
  String winner = "you win!";
  display.clearDisplay();
  
  if(win) {
    displayWin();
  }else {
    displayScoreLeft();
  }
  
  cpuPaddle();
  paddle();
  drawCourt();
 
  //move paddle up
  if(digitalRead(3) == LOW && paddleNum > 1) {
    paddleNum -= 1;
    digitalWrite(3, HIGH);
  }
 
  //move paddle down
  if(digitalRead(2) == LOW && paddleNum < 43) {
    paddleNum += 1;
    digitalWrite(2, HIGH);
  }
    
  // ball movement logic
  if (!horizontal) {
    ballRight();
  } else {
    ballLeft();
  }
  if (!vertical) {
    ballDown();
  } else {
    ballUp();
  }
  
  //tally score
  if(ball_x <= 1) {
    score = 0;
  }
  if((ball_x == 11 && ball_y <= paddleNum + 20 && ball_y >= paddleNum)) {
    score += 1;
    if(score == 2) {
      win = true;
    }
  }
 
  //bounce ball off right paddle
  if(ball_x >= 114) {
    horizontal = true;
  }
  
  //bounce ball off left wall
  if(ball_x <= 1) {
    horizontal = false;
  }
  
  //bounce ball off bottom wall
  if(ball_y >= 61) {
    vertical = true;
  }
  
  //bounce ball off top wall
  if(ball_y <= 1) {
    vertical = false;
  }

  //bounce ball off back of paddle
  if(ball_x == 9 && ball_y <= paddleNum + 20 && ball_y >= paddleNum) {
    horizontal = true;
  }

  //bounce ball off front of paddle
  if(ball_x == 11 && ball_y <= paddleNum + 20 && ball_y >= paddleNum) {
    horizontal = false;
  }

  //cpuPaddle movement
  if(ball_y <= 10) {
    cpuPaddleNum = 1;
  }else if(ball_y >= 51) {
    cpuPaddleNum = 43;
  }else{
    cpuPaddleNum = ball_y - 10;
  }
  
  display.display();
}

void start2PlayersGame() {
  // Your logic for the 2 players game goes here
  // This function should handle the game mechanics for 2 players mode
  display.clearDisplay();
  
  if(win) {
    displayWin();
  }else {
    displayScoreLeft();
    displayScoreRight();
  }
  
  rightPaddle();
  leftPaddle();
  drawCourt();
 
  //move left paddle up
  if(digitalRead(3) == LOW && paddleNumLeft > 1) {
    paddleNumLeft -= 1;
    digitalWrite(3, HIGH);
  }
 
  //move left paddle down
  if(digitalRead(2) == LOW && paddleNumLeft < 43) {
    paddleNumLeft += 1;
    digitalWrite(2, HIGH);
  }

  //move right right paddle up
  if(digitalRead(6) == LOW && paddleNumRight > 1) {
    paddleNumRight -= 1;
    digitalWrite(6, HIGH);
  }
 
  //move right right paddle down
  if(digitalRead(5) == LOW && paddleNumRight < 43) {
    paddleNumRight += 1;
    digitalWrite(5, HIGH);
  }
    
  // ball movement logic
  if (!horizontal) {
    ballRight();
  } else {
    ballLeft();
  }
  if (!vertical) {
    ballDown();
  } else {
    ballUp();
  }
  
  //tally scoreLeft
  if(ball_x <= 1) {
    scoreLeft = 0;
  }
  if((ball_x == 11 && ball_y <= paddleNumLeft + 20 && ball_y >= paddleNumLeft)) {
    scoreLeft += 1;
    if(scoreLeft >= scoreRight + 2) {
      winner = "p1 wins!";
      win = true;
    }
  }

  //tally scoreRight
  if(ball_x >= 123) {
    scoreRight = 0;
  }
  if(ball_x == 114 && ball_y <= paddleNumRight + 20 && ball_y >= paddleNumRight) {
    scoreRight += 1;
    if(scoreRight >= scoreLeft + 2) {
      winner = "p2 wins!";
      win = true;
    }
  }
 
  //bounce ball off right wall
  if(ball_x >= 123) {
    horizontal = true;
  }
  
  //bounce ball off left wall
  if(ball_x <= 1) {
    horizontal = false;
  }
  
  //bounce ball off bottom wall
  if(ball_y >= 61) {
    vertical = true;
  }
  
  //bounce ball off top wall
  if(ball_y <= 1) {
    vertical = false;
  }

  //bounce ball off back of left paddle
  if(ball_x == 9 && ball_y <= paddleNumLeft + 20 && ball_y >= paddleNumLeft) {
    horizontal = true;
  }

  //bounce ball off front of left paddle
  if(ball_x == 11 && ball_y <= paddleNumLeft + 20 && ball_y >= paddleNumLeft) {
    horizontal = false;
  }

  //bounce ball off front of right paddle
  if(ball_x == 114 && ball_y <= paddleNumRight + 20 && ball_y >= paddleNumRight) {
    horizontal = true;
  }

  //bounce ball off back of right paddle
  if(ball_x == 117 && ball_y <= paddleNumRight + 20 && ball_y >= paddleNumRight) {
    horizontal = false;
  }
  
  display.display();
}