#define BLYNK_TEMPLATE_ID "TMPL2o2SqlCwx"
#define BLYNK_TEMPLATE_NAME "Quickstart Template"
#define BLYNK_AUTH_TOKEN "ctuVteBw_QTpAOSQcU5f3Z34IiO0CdjU"

#include <WiFi.h>
#include <WiFiClientSecure.h>
#include <BlynkSimpleEsp32.h>
#include <HTTPClient.h>
#include <EmonLib.h>
#include <time.h>
#include <ArduinoJson.h>

char ssid[] = "Wokwi-GUEST";
char pass[] = "";

char auth[] = "ctuVteBw_QTpAOSQcU5f3Z34IiO0CdjU";

const char* appwriteHost = "cloud.appwrite.io";
const char* projectID = "66ad2625001249bd442c";
const char* collectionID = "66ad2db100146cb4e965";
const char* databaseID = "66ad2c74001a1bc74f45";
const char* apiKey = "c82a5f96d2690914c4524bed259b33fe68b83243289a42843f581ac53c3108e7f667c5154f5d36de6168045102d9a05b8a6cc03e5978a6584f063cfbea4d15c6d8c869a9bc3d3499f00318e086e498b6df9d40f9b8d1b7996cadfedb687645c5b359c40e027011b7df381b30d0648ac0bc31c970b9a16f53fa73314bf5c64d40";
const char* secondCollectionID = "66ad2cb5002b7c3a820b";

EnergyMonitor emon1;

unsigned long lastMillis = 0;
unsigned long lastDbCheckMillis = 0;
float energy = 0.0;
bool deviceStatus = false;

#define RELAY_PIN 4
#define DB_CHECK_INTERVAL 500 // 0.5 seconds

void setup() {
  Serial.begin(9600);
  Blynk.begin(auth, ssid, pass);

  pinMode(RELAY_PIN, OUTPUT);

  emon1.voltage(12, 320, 1.7);
  emon1.current(12, 90);

  configTime(0, 0, "pool.ntp.org", "time.nist.gov");
  while (!time(nullptr)) {
    Serial.println("Waiting for time synchronization...");
    delay(1000);
  }

  String deviceId = "Smart Socket";
  String timestamp = getFormattedTime();
  String userId = "your_user_id";
  
  if (deviceExistsInDB(deviceId)) {
    updateDeviceStatusFromDB(deviceId);
  }
}

String getFormattedTime() {
  time_t now = time(nullptr);
  struct tm timeinfo;
  gmtime_r(&now, &timeinfo);
  char buffer[25];
  strftime(buffer, sizeof(buffer), "%Y-%m-%dT%H:%M:%SZ", &timeinfo);
  return String(buffer);
}

String urlEncode(const String& str) {
  String encoded = "";
  for (size_t i = 0; i < str.length(); ++i) {
    char c = str.charAt(i);
    if (c == ' ') {
      encoded += "+";
    } else if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '-' || c == '_' || c == '.' || c == '~') {
      encoded += c;
    } else {
      encoded += String("%") + String((int)c, HEX);
    }
  }
  return encoded;
}

bool deviceExistsInDB(const String& deviceId) {
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = String("https://") + appwriteHost + "/v1/databases/" + String(databaseID) + "/collections/" + String(secondCollectionID) + "/documents";
    url += "?filters[deviceName]=" + urlEncode(deviceId);
    http.begin(url);
    http.addHeader("X-Appwrite-Project", projectID);
    http.addHeader("X-Appwrite-Key", apiKey);

    int httpResponseCode = http.GET();
    if (httpResponseCode == 200) {
      String response = http.getString();
      Serial.println("Response: " + response);

      DynamicJsonDocument doc(1024);
      DeserializationError error = deserializeJson(doc, response);

      if (error) {
        Serial.print("JSON deserialization failed: ");
        Serial.println(error.c_str());
        http.end();
        return false;
      }

      JsonArray documents = doc["documents"].as<JsonArray>();
      if (documents.size() > 0) {
        return true;
      } else {
        Serial.println("No documents found for device");
      }
    } else {
      Serial.print("Error on GET request: ");
      Serial.println(httpResponseCode);
      handleHttpError(httpResponseCode);
    }
    http.end();
  } else {
    Serial.println("Error in WiFi connection");
  }
  return false;
}

void updateDeviceStatusFromDB(const String& deviceId) {
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = String("https://") + appwriteHost + "/v1/databases/" + String(databaseID) + "/collections/" + String(secondCollectionID) + "/documents";
    url += "?filters[deviceName]=" + urlEncode(deviceId);
    http.begin(url);
    http.addHeader("X-Appwrite-Project", projectID);
    http.addHeader("X-Appwrite-Key", apiKey);

    int httpResponseCode = http.GET();
    if (httpResponseCode == 200) {
      String response = http.getString();
      Serial.println("Response: " + response);

      DynamicJsonDocument doc(1024);
      DeserializationError error = deserializeJson(doc, response);

      if (error) {
        Serial.print("JSON deserialization failed: ");
        Serial.println(error.c_str());
        http.end();
        return;
      }

      JsonArray documents = doc["documents"].as<JsonArray>();
      if (documents.size() > 0) {
        bool status = documents[1]["status"];
        deviceStatus = status;
        digitalWrite(RELAY_PIN, deviceStatus ? HIGH : LOW);
        Serial.print("Device status updated from DB: ");
        Serial.println(deviceStatus ? "ON" : "OFF");
      } else {
        Serial.println("No documents found for device");
      }
    } else {
      Serial.print("Error on GET request: ");
      Serial.println(httpResponseCode);
      handleHttpError(httpResponseCode);
    }
    http.end();
  } else {
    Serial.println("Error in WiFi connection");
  }
}

void sendDataToAppwrite(const String& deviceId, const String& userId, bool status, const String& timestamp) {
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = String("https://") + appwriteHost + "/v1/databases/" + String(databaseID) + "/collections/" + String(secondCollectionID) + "/documents";
    http.begin(url);
    http.addHeader("Content-Type", "application/json");
    http.addHeader("X-Appwrite-Project", projectID);
    http.addHeader("X-Appwrite-Key", apiKey);

    String jsonPayload = "{\"documentId\": \"unique()\", \"data\": {\"deviceName\": \"" + deviceId + "\", \"userId\": \"" + userId + "\", \"status\": " + (status ? "true" : "false") + "}}";
                        
    int httpResponseCode = http.POST(jsonPayload);

    if (httpResponseCode > 0) {
      String response = http.getString();
      Serial.println(httpResponseCode);
      Serial.println(response);
    } else {
      Serial.print("Error on sending POST: ");
      Serial.println(httpResponseCode);
      handleHttpError(httpResponseCode);
    }

    http.end();
  } else {
    Serial.println("Error in WiFi connection");
  }
}

void handleHttpError(int code) {
  String errorMessage;
  switch (code) {
    case 400:
      errorMessage = "Bad Request";
      break;
    case 401:
      errorMessage = "Unauthorized";
      break;
    case 403:
      errorMessage = "Forbidden";
      break;
    case 404:
      errorMessage = "Not Found";
      break;
    case 500:
      errorMessage = "Internal Server Error";
      break;
    default:
      errorMessage = "Unknown Error";
  }
  Serial.println("HTTP Response Error: " + errorMessage);
}

void loop() {
  Blynk.run();

  unsigned long currentMillis = millis();

  emon1.calcVI(20, 2000);
  float voltage = emon1.Vrms;
  float current = emon1.Irms;
  float power = emon1.realPower;

  float deltaTime = (currentMillis - lastMillis) / 1000.0;
  lastMillis = currentMillis;
  energy += power * deltaTime;

  Blynk.virtualWrite(V4, voltage);
  Blynk.virtualWrite(V0, current);
  Blynk.virtualWrite(V1, power);
  Blynk.virtualWrite(V3, energy);

  String deviceId = "Smart Socket"; // Declare deviceId here
  String timestamp = getFormattedTime();
  String userId = "your_user_id";

  if (currentMillis - lastDbCheckMillis >= DB_CHECK_INTERVAL) {
    lastDbCheckMillis = currentMillis;
    if (deviceExistsInDB(deviceId)) {
      updateDeviceStatusFromDB(deviceId);
    }
  }

   float pricePerKWh = 1.753;
  float totalPrice = energy * pricePerKWh;

 // Send data to Appwrite (first collection)
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = String("https://") + appwriteHost + "/v1/databases/" + String(databaseID) + "/collections/" + String(collectionID) + "/documents";
    http.begin(url);
    http.addHeader("Content-Type", "application/json");
    http.addHeader("X-Appwrite-Project", projectID);
    http.addHeader("X-Appwrite-Key", apiKey);

    String jsonPayload = "{\"documentId\": \"unique()\", \"data\": {\"deviceId\": \"" + deviceId + "\", \"timestamp\": \"" + timestamp + "\", \"voltage\": " + String(voltage) + 
                        ", \"current\": " + String(current) + 
                        ", \"power\": " + String(power) + 
                        ",\"price\": " + String(totalPrice) + 
                        ", \"energy\": " + String(energy) + 
                        "}}";
                        
    int httpResponseCode = http.POST(jsonPayload);


    if (httpResponseCode > 0) {
      String response = http.getString();
      Serial.println(httpResponseCode);
      Serial.println(response);
    } else {
      Serial.print("Error on sending POST: ");
      Serial.println(httpResponseCode);
    }

    http.end();
  } else {
    Serial.println("Error in WiFi connection");
  }


  Serial.print("Voltage: ");
  Serial.print(voltage);
  Serial.print(" V, Current: ");
  Serial.print(current);
  Serial.print(" A, Power: ");
  Serial.print(power);
  Serial.print(" W, Energy: ");
  Serial.print(energy);
  Serial.print(" Joules, Status: ");
  Serial.println(deviceStatus ? "ON" : "OFF");

  delay(500); // 500 milliseconds delay
}