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

// OLED Display Configuration
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// Sensor Pin Definitions
#define HEART_SENSOR 36  // GPIO 36 (VN) for analog input
#define TEMP_SENSOR 39  // GPIO 39 (VP) for analog input
#define ALERT_LED 13     // Alert LED for abnormal readings

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

    // Initialize OLED Display
    if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
        Serial.println("SSD1306 OLED Display Failed!");
        while (1);
    }
    display.clearDisplay();
    
    pinMode(ALERT_LED, OUTPUT);
}

void loop() {
    // Simulate Heart Rate & Temperature
    int heartRate = analogRead(HEART_SENSOR) / 10;  // Scale 0-100
    int temperature = map(analogRead(TEMP_SENSOR), 0, 4095, 30, 40); // Simulated Temp in °C

    // Display on OLED
    display.clearDisplay();
    display.setTextSize(2);
    display.setTextColor(WHITE);
    display.setCursor(10, 10);
    display.print("HR: "); display.print(heartRate); display.println(" BPM");
    display.print("Temp: "); display.print(temperature); display.println(" C");
    display.display();

    // Check for abnormal conditions
    if (heartRate < 50 || heartRate > 120 || temperature > 38) {
        digitalWrite(ALERT_LED, HIGH);  // Turn on Alert LED
    } else {
        digitalWrite(ALERT_LED, LOW);
    }

    Serial.print("Heart Rate: "); Serial.print(heartRate); Serial.println(" BPM");
    Serial.print("Temperature: "); Serial.print(temperature); Serial.println(" C");
    Serial.println("---------------------");

    delay(1000);
}