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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1  // Change to -1 for no reset pin
#define SCREEN_ADDRESS 0x3C

Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

const char* ssid = "Wokwi-GUEST"; // Replace with your WiFi SSID
const char* password = "";        // Replace with your WiFi password

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

  if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("Failed to start SSD1306 OLED"));
    while (1);
  }

  delay(2000);
  oled.clearDisplay();
  
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  oled.setCursor(15, 30);
  oled.println("Welcome to APEX");
  oled.display();
  
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("");
  Serial.println("WiFi connected.");
  Serial.println(WiFi.localIP());

  delay(2000);

  for (int i = 0; i < 3; i++) {
    displayLoadingAnimation();
    delay(500);
  }

  oled.clearDisplay();
  
  Serial.print("Connecting to ");
  Serial.println(ssid);
}

void displayLoadingAnimation() {
  oled.clearDisplay();
  oled.setTextSize(1);
  oled.setTextColor(WHITE);
  oled.setCursor(40, 30);
  oled.print("Loading");
  for (int i = 0; i < 3; i++) {
    oled.print(".");
    oled.display();
    delay(500);
  }
}

void loop() {
  String network = get_network();
  String battery = get_battery();

  display_battery_and_network_animation(battery, network);

  displaySymbolsAnimation();
  delay(100); // Adjust delay as needed
}

String sendCommand(const String &command) {
  Serial2.println(command);
  delay(100);
  return Serial2.readString();
}

String get_network() {
  String response = sendCommand("AT+CSQ");
  Serial.println(response);

  int index1 = response.indexOf(":");
  int index2 = response.indexOf(",");
  String result = response.substring(index1 + 1, index2);
  result.trim();

  int signalStrength = result.toInt();
  if (signalStrength == 99) {
    return "0";
  } else if (signalStrength >= 2 && signalStrength <= 9) {
    return "20";
  } else if (signalStrength >= 10 && signalStrength <= 14) {
    return "40";
  } else if (signalStrength >= 15 && signalStrength <= 19) {
    return "60";
  } else if (signalStrength >= 20 && signalStrength <= 31) {
    return "99";
  }

  return "0";
}

String get_battery() {
  String response = sendCommand("AT+CBC");
  Serial.println(response);

  int index1 = response.indexOf(",");
  int index2 = response.indexOf(",", index1 + 1);
  String result = response.substring(index1 + 1, index2);
  result.trim();

  return result;
}

void display_battery_and_network_animation(const String &battery, const String &network) {
  oled.clearDisplay();

  // Display Battery Indicator Animation on the top right corner
  for (int i = 0; i <= battery.toInt(); i += 10) {
    oled.setTextSize(1);
    oled.setTextColor(WHITE);
    oled.setCursor(SCREEN_WIDTH - 40, 5);
    oled.print("Bat:");
    oled.print(i);
    oled.print("%");
    oled.drawRect(SCREEN_WIDTH - 52, 20, 10, 20, WHITE);
    oled.fillRect(SCREEN_WIDTH - 52, 20, (int)(10 * i / 100), 20, WHITE);
    oled.display();
    delay(100);
  }

  // Display WiFi Indicator Animation next to Battery
  for (int i = 0; i <= network.toInt(); i += 20) {
    oled.setTextSize(1);
    oled.setTextColor(WHITE);
    oled.setCursor(SCREEN_WIDTH - 40, 35);
    oled.print("WiFi");
    int net = i / 20;
    int x1 = SCREEN_WIDTH - 30, y1 = 20, x2 = 10, y2 = 4;
    for (int j = 1; j <= net; j++) {
      oled.fillRect(x1, y1, x2, y2, WHITE);
      y1 += 6;
      y2 += 6;
    }
    oled.display();
    delay(100);
  }

  delay(2000);  // Adjust delay as needed
}

void displaySymbolsAnimation() {
  //oled.clearDisplay();
  
  // Display Heart Symbol
  oled.setTextSize(2);
  oled.setTextColor(WHITE);
  oled.setCursor(5, 5);
  oled.print("❤");

  // Display Temperature Symbol
  oled.setTextSize(2);
  oled.setTextColor(WHITE);
  oled.setCursor(40, 5);
  oled.print("°C");

  // Display Percentage Symbol
  oled.setTextSize(2);
  oled.setTextColor(WHITE);
  oled.setCursor(75, 5);
  oled.print("%");

  oled.display();
}