#include <SPI.h>  // Required for shield communication
#include <WiFi.h>

// Wi-Fi network configuration
char ssid[] = "Wokwi-GUEST";   // Your network SSID (name)
char pass[] = "";   // Your network password (fill this in)

int LED_PIN = 13;  // GPIO pin connected to an LED

WiFiClient client;  // Create a Wi-Fi client

unsigned long myTalkBackID =  		51190;
const char * myTalkBackKey = "JUVABF9FB6B7XO84";

void setup() {
  Serial.begin(115200);          // Initialize serial communication for debugging
  pinMode(LED_PIN, OUTPUT);      // Set the LED pin as an output
}

void loop() {
  // Connect or reconnect to Wi-Fi
  if (WiFi.status() != WL_CONNECTED) {
    Serial.print("Attempting to connect to SSID: ");
    Serial.println(String(ssid)); // Print the network SSID being connected to
    while (WiFi.status() != WL_CONNECTED) {
      WiFi.begin(ssid, pass); // Start the Wi-Fi connection
      Serial.print(".");
      delay(2000); // Wait for 2 seconds before retrying
    }
    Serial.println("\nConnected.");
  }

  // Create the TalkBack URI
  String tbURI = String("/talkbacks/") + String(myTalkBackID) + String("/commands/execute");

  // Create the message body for the POST request out of the values
  String postMessage = String("api_key=") + String(myTalkBackKey); // Construct the POST data

  // Make a string for any commands in the queue
  String newCommand = String();

  // Make the POST request to ThingSpeak
  int x = httpPOST(tbURI, postMessage, newCommand); // Call the HTTP POST function
  client.stop(); // Close the client connection

  // Check the result
  if (x == 200) {
    Serial.println("Checking queue...");
    // Check for a command returned from TalkBack
    if (newCommand.indexOf("led on") == -1 && newCommand.indexOf("led off") == -1) {
      Serial.println("No command or syntax error!");
    } else {
      if (newCommand.indexOf("led on") != -1) {
        Serial.println("New command: Turn LED on");
        digitalWrite(LED_PIN, HIGH); // Turn on the LED
      } else if (newCommand.indexOf("led off") != -1) {
        Serial.println("New command: Turn LED off");
        digitalWrite(LED_PIN, LOW); // Turn off the LED
      }
    }
  } else {
    Serial.println("Problem checking queue. HTTP error code " + String(x));
  }

  delay(5000); // Wait 5 seconds before checking the queue again
}

// General function to POST to ThingSpeak
int httpPOST(String uri, String postMessage, String &response) {

  bool connectSuccess = false;
  connectSuccess = client.connect("api.thingspeak.com", 80); // Connect to ThingSpeak server

  if (!connectSuccess) {
    return -301; // Connection error
  }

  postMessage += "&headers=false";

  String Headers =  String("POST ") + uri + String(" HTTP/1.1\r\n") +
                    String("Host: api.thingspeak.com\r\n") +
                    String("Content-Type: application/x-www-form-urlencoded\r\n") +
                    String("Connection: close\r\n") +
                    String("Content-Length: ") + String(postMessage.length()) +
                    String("\r\n\r\n");

  client.print(Headers); // Send HTTP headers
  client.print(postMessage); // Send POST data

  long startWaitForResponseAt = millis();
  while (client.available() == 0 && millis() - startWaitForResponseAt < 5000) {
    delay(100); // Wait for a response with a timeout of 5 seconds
  }

  if (client.available() == 0) {
    return -304; // Didn't get server response in time
  }

  if (!client.find(const_cast<char *>("HTTP/1.1"))) {
    return -303; // Couldn't parse response (didn't find HTTP/1.1)
  }

  int status = client.parseInt(); // Parse HTTP response code
  if (status != 200) {
    return status; // Return HTTP status code
  }

  if (!client.find(const_cast<char *>("\n\r\n"))) {
    return -303; // Couldn't parse response
  }

  String tempString = String(client.readString()); // Read the response
  response = tempString;
  // Serial.println("response: " + response);

  return status; // Return HTTP status code
}