#include <WiFi.h>

const int p_LED = 2;

#include <PubSubClient.h>

const char* mqtt_server = "broker.hivemq.com";
const int mqtt_port = 1883;

//WiFi Credentials
const char* ssid     = "Wokwi-GUEST";         // The SSID (name) of the Wi-Fi network you want to connect to
const char* password = "";     // The password of the Wi-Fi network

WiFiClient wifi_client;

struct Schedule {
  const char* name;
  const int pin;
  unsigned long T;
  unsigned long t_last;
};

Schedule sch_table[] = {
  {"blue", 27, 200, 0}, //blue
  {"green", 26, 123, 0}, //green
  {"yellow", 14, 333, 0}, //yellow
  {"red", 13, 421, 0},  //red
};

int N_sch = sizeof(sch_table)/sizeof(Schedule);

//pre declare call back
void mqtt_callback(char* topic, byte* payload, unsigned int length);

//PubSubClient constructor object
PubSubClient mqtt_client(mqtt_server, mqtt_port, mqtt_callback, wifi_client);

// Topics
// to publish
// char* pub_topic = "apu/cs452/yeh/button";
// to subscribe
char* sub_topic = "apu/cubesat/antenna/switch/1";
// char* sub_topic = "apu/#";
// char* sub_topic_2 = "apu/cs452/yeh/message";

//random cliend ID
char* cliend_id = "apu_cubesat_antenna_switch_1";

void handleSwitch(byte* payload, uint16_t length);
// void handleMessage(byte* payload, uint16_t length);

void setup() {
  Serial.begin(115200);
  delay(100);
  Serial.println("Pub Client for LED");
  Serial.println("");
  Serial.println("(c) 2023 James Yeh");
  Serial.println();

  //  wifiMulti.addAP("APU-MYDEVICES");

  Serial.println("Connecting...");
  WiFi.begin(ssid);             // Connect to the network

  connectWiFi();

  for (int i = 0; i < N_sch; i++) {
    pinMode(sch_table[i].pin, OUTPUT);
    digitalWrite(sch_table[i].pin, LOW);
  }
}

//MQTT callback
void mqtt_callback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] ");

   //only print the payload - can modify code to call other functions based on topic
   for (int i = 0; i < length; i++) {
     Serial.print((char)payload[i]);
   }
   Serial.println();
  if (strcmp(topic, sub_topic) == 0) {
    handleSwitch(payload, length);
  }
  // if (strcmp(topic, sub_topic_2) == 0) {
  //   handleMessage(payload, length);
  // }


}

void handleSwitch(byte* payload, uint16_t length) {
  if (length <= 0)
    return;
  char c = (char)payload[0];
        // Serial.println(c);
  if ((c >= '1') && (c <= '4')) {
      int j = c - '1';
      // Serial.println(j);
      for (int i = 0; i < N_sch; i++) {
        if (i == j)
          digitalWrite(sch_table[i].pin, HIGH);
        else
          digitalWrite(sch_table[i].pin, LOW);                  
      }
  }
}

void loop() {
  //reconnect if disconnected
  if (!mqtt_client.connected()) {
    mqtt_reconnect();
  }
  mqtt_client.loop();
}

//(re)connect to MQTT broker
void mqtt_reconnect() {
  // Loop until we're reconnected
  while (!mqtt_client.connected()) {

    Serial.print("Attempting MQTT connection...");
    // Connect MQTT
    //    if (client.connect(cliend_id, username, password)) {
    if (mqtt_client.connect(cliend_id)) {
      Serial.println("connected");
      //Subscribe
      mqtt_client.subscribe(sub_topic, 1);
      // mqtt_client.subscribe(sub_topic_2, 1);
    } else {
      Serial.print("failed, rc=");
      Serial.print(mqtt_client.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void connectWiFi() {
  Serial.print("MAC: ");
  Serial.println(WiFi.macAddress());

  while (WiFi.status() != WL_CONNECTED) { // Wait for the Wi-Fi to connect
    //  while (wifiMulti.run() != WL_CONNECTED) { // Wait for the Wi-Fi to connect: scan for Wi-Fi networks, and connect to the strongest of the networks above
    delay(250);
    Serial.print('.');
    digitalWrite(p_LED, !digitalRead(p_LED));
  }
  digitalWrite(p_LED, LOW);

  Serial.println('\n');
  Serial.print("Connected to ");
  Serial.println(WiFi.SSID());               // Tell us what network we're connected to
  Serial.print("IP address:\t");
  Serial.println(WiFi.localIP());            // Send the IP address of the ESP8266 to the computer
}