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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

int outpin = 2;
int alertpin = 14;
float maxSpeedLimit = 16;
int potpin = 15;

int speedval;
float motorRPM = 1000.0; // Motor's RPM
float wheelDiameter = 0.1; // Wheel diameter in meters (adjust as needed)

// Color definitions
#define BLACK           0x0000
#define BLUE            0x001F
#define RED             0xF800
#define GREEN           0x07E0
#define CYAN            0x07FF
#define MAGENTA         0xF81F
#define YELLOW          0xFFE0  
#define WHITE           0xFFFF

void testfillrect(void) {
  display.clearDisplay();

  for(int16_t i=0; i<display.height()/2; i+=3) {
    // The INVERSE color is used so rectangles alternate white/black
    display.fillRect(i, i, display.width()-i*2, display.height()-i*2, WHITE);
    display.display(); // Update screen with each newly-drawn rectangle
    delay(1);
  }

  delay(2000);
}

void displaySpeedInfo(float speedKMH) {
  display.clearDisplay();

  display.setTextSize(1);             // Normal 1:1 pixel scale

  // Change text color based on speed
  if (speedKMH <= 4) {
    display.setTextColor(YELLOW);
  } else if (speedKMH <= 8) {
    display.setTextColor(RED);
  } else if (speedKMH <= 12) {
    display.setTextColor(GREEN);
  } else {
    display.setTextColor(CYAN);
  }

  display.setCursor(0,0);             // Start at top-left corner
  display.println(F("EBike Controller"));

  display.println("");display.println("");

  // Change text size based on speed
  if (speedKMH <= 4) {
    display.setTextSize(1);
  } else if (speedKMH <= 8) {
    display.setTextSize(1.5);
  } else if (speedKMH <= 12) {
    display.setTextSize(2);
  } else {
    display.setTextSize(2.5);
  }

  display.print("Speed: ");
  display.println("");

  display.print(speedKMH, 1); // Display speed with one decimal place
  display.print(" km/h");

  display.display();
}

void setup() {
  pinMode(outpin, OUTPUT);
  pinMode(alertpin, OUTPUT);

  Wire.begin();
  Serial.begin(9600);

  // 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
  }

  display.display();
  delay(2000); // Pause for 2 seconds

  // Clear the buffer
  display.clearDisplay();

  // Draw a single pixel in white
  display.drawPixel(10, 10, WHITE);

  // Show the display buffer on the screen. You MUST call display() after
  // drawing commands to make them visible on screen!
  display.display();
  delay(2000);
  
  display.clearDisplay();
  display.setTextSize(2); // Adjust text size as needed
  display.setTextColor(WHITE);
  testfillrect();
}

void loop() {
  speedval = analogRead(potpin);
  if (speedval >= 0 && speedval <= 50) {speedval = 0;}
  speedval = map(speedval, 0, 1024, 0, 255);

  Serial.println("");Serial.print("speedval: ");Serial.println(speedval);Serial.println("");
  
  analogWrite(outpin, speedval);
  
  // Calculate speed in km/h
  float speedKMH = (speedval / 255.0) * (motorRPM * wheelDiameter * 3.14159265359 * 60.0) / 1000.0;

  //  display
  displaySpeedInfo(speedKMH);

  //  maxSpeedLimit condition
  if (speedKMH >= maxSpeedLimit ) {digitalWrite(alertpin, HIGH);}
  else {digitalWrite(alertpin, LOW);}
  
  delay(20);
}



























// ---------------------------------------------------------------------------



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

// #define SCREEN_WIDTH 128
// #define SCREEN_HEIGHT 64
// #define OLED_RESET -1
// #define SCREEN_ADDRESS 0x3C ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
// Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// int outpin = 2;
// int alertpin = 14;
// float maxSpeedLimit = 16;
// int potpin = 15;

// int speedval;
// float motorRPM = 1000.0; // Motor's RPM
// float wheelDiameter = 0.1; // Wheel diameter in meters (adjust as needed)

// void testfillrect(void) {
//   display.clearDisplay();

//   for(int16_t i=0; i<display.height()/2; i+=3) {
//     // The INVERSE color is used so rectangles alternate white/black
//     display.fillRect(i, i, display.width()-i*2, display.height()-i*2, SSD1306_INVERSE);
//     display.display(); // Update screen with each newly-drawn rectangle
//     delay(1);
//   }

//   delay(2000);
// }

// void displaySpeedInfo(float speedKMH) {
//   display.clearDisplay();

//   display.setTextSize(1);             // Normal 1:1 pixel scale
//   display.setTextColor(SSD1306_WHITE);        // Draw white text
//   display.setCursor(0,0);             // Start at top-left corner
//   display.println(F("EBike Controller"));

//   display.println("");display.println("");

//   // Draw 2X-scale text
//   display.setTextSize(2);             
//   display.setTextColor(SSD1306_WHITE);
  
//   display.print("Speed: ");
//   display.println("");

//   display.print(speedKMH, 1); // Display speed with one decimal place
//   display.print(" km/h");

//   display.display();
// }


// void setup() {
//   pinMode(outpin, OUTPUT);
//   pinMode(alertpin, OUTPUT);

//   Wire.begin();
//   Serial.begin(9600);

  
//   // 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
//   }

//   display.display();
//   delay(2000); // Pause for 2 seconds

//   // Clear the buffer
//   display.clearDisplay();

//   // Draw a single pixel in white
//   display.drawPixel(10, 10, SSD1306_WHITE);

//   // Show the display buffer on the screen. You MUST call display() after
//   // drawing commands to make them visible on screen!
//   display.display();
//   delay(2000);
  
//   display.clearDisplay();
//   display.setTextSize(2); // Adjust text size as needed
//   display.setTextColor(SSD1306_WHITE);
//   testfillrect();
// }

// void loop() {
//   speedval = analogRead(potpin);
//   if (speedval >= 0 && speedval <= 50) {speedval = 0;}
//   speedval = map(speedval, 0, 1024, 0, 255);

//   Serial.println("");Serial.print("speedval: ");Serial.println(speedval);Serial.println("");
  
//   analogWrite(outpin, speedval);
  
//   // Calculate speed in km/h
//   float speedKMH = (speedval / 255.0) * (motorRPM * wheelDiameter * 3.14159265359 * 60.0) / 1000.0;

//   //  display
//   displaySpeedInfo(speedKMH);

//   //  maxSpeedLimit condition
//   if (speedKMH >= maxSpeedLimit ) {digitalWrite(alertpin, HIGH);}
//   else {digitalWrite(alertpin, LOW);}
  
//   delay(20);
// }