#ifndef MQTT_H
#define MQTT_H

#include <PubSubClient.h>
#include <WiFiClient.h>
#include <ArduinoJson.h>

const char* mqtt_server = "broker.emqx.io";
const int mqtt_port = 1883;

// Topics
const char* mqtt_topic_state = "ups/dev15/state";
const char* mqtt_topic_cmd   = "ups/dev15/cmd";

WiFiClient espClient;
PubSubClient mqttClient(espClient);

unsigned long lastMqttReconnectAttempt = 0;
unsigned long lastMqttPublish = 0;
const unsigned long mqttPublishInterval = 2000; // Publish state every 2 seconds

// Forward declaration
void mqttPublishState();

void mqttCallback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Message arrived on topic: ");
  Serial.print(topic);
  Serial.print(". Message: ");
  String messageTemp;
  
  for (int i = 0; i < length; i++) {
    Serial.print((char)payload[i]);
    messageTemp += (char)payload[i];
  }
  Serial.println();

  // Parse command
  if (String(topic) == mqtt_topic_cmd) {
    DynamicJsonDocument doc(256);
    DeserializationError error = deserializeJson(doc, payload, length);
    if (!error) {
      String cmd = doc["cmd"].as<String>();
      String v = doc["val"].as<String>();
      bool updated = false;

      if (cmd == "on") {
        bool tgtState = v != "0";
        if (tgtState != powerOutputActive) {
          // This function is defined in upsSvr.h / main logic
          // Note: mqtt.h is included after or before? Need to ensure it can call setOutputPowerState
          // Actually, setOutputPowerState is declared in upsCfg.h maybe?
          // If compilation fails, we can just set the flag. Wait, let's use the function since it's global.
          setOutputPowerState(tgtState);
          updated = true;
        }
      } else if (cmd == "auto") {
        uint8_t tmpAutoOnMode = v.toInt();
        if ((tmpAutoOnMode != cfgAutoOn) && (tmpAutoOnMode <= 2)) {
          cfgAutoOn = tmpAutoOnMode;
          configChanged = true;
          updated = true;
        }
      } else if (cmd == "shutdown") {
        uint16_t tSec = v.toInt();
        if (tSec > 999) tSec = 999;
        uint32_t nanoT = ((uint32_t)tSec) * 1000000UL;
        if (nanoT < 999999) nanoT = 999999;
        bool ok = setPersistentShutdown(nanoT);
        if (cfgShutdownInSeconds != tSec && ok) {
          cfgShutdownInSeconds = tSec;
          configChanged = true;
          updated = true;
        }
      } else if (cmd == "shutlv") {
        int16_t lv = v.toInt();
        if (lv >= 0 && lv <= 5) {
          if (lv != cfgShutdownSuggestion) {
            cfgShutdownSuggestion = lv;
            configChanged = true;
            updated = true;
          }
        }
      } else if (cmd == "cm") {
        int16_t i = v.toInt();
        if (i >= 0 && i <= 9) {
          cfgChargeMode = i;
          configChanged = true;
          updated = true;
        }
      } else if (cmd == "coil") {
        int16_t i = v.toInt();
        if (i >= 0 && i <= 5) {
          cfgInputLostTriggerChargeMode = i;
          configChanged = true;
          updated = true;
        }
      } else if (cmd == "covp") {
        int16_t i = v.toInt();
        if (i > 1) i = 1;
        if (i != cfgChargeOvervoltageProtection) {
          cfgChargeOvervoltageProtection = i;
          configChanged = true;
          updated = true;
        }
      } else if (cmd == "rofc") {
        int16_t i = v.toInt();
        if (i > 0 && needFullChargeOnce) {
          resetOnGoingFullChargeAfterLineLost();
          updated = true;
        }
      } else if (cmd == "car") {
        int16_t i = v.toInt();
        if (i > 1) i = 1;
        if (i != cfgChargeAutomaticReducer) {
          cfgChargeAutomaticReducer = i;
          configChanged = true;
          updated = true;
        }
      }

      if (updated) {
        mqttPublishState();
      }
    }
  }
}

boolean mqttReconnect() {
  String clientId = "UPS_DEV15_" + String(random(0xffff), HEX);
  Serial.print("Attempting MQTT connection as ");
  Serial.println(clientId);
  if (mqttClient.connect(clientId.c_str())) {
    Serial.println("MQTT Connected");
    // Once connected, publish an announcement...
    mqttClient.publish("ups/dev15/status", "online");
    // ... and resubscribe
    mqttClient.subscribe(mqtt_topic_cmd);
  } else {
    Serial.print("failed, rc=");
    Serial.print(mqttClient.state());
    Serial.println(" try again in 5 seconds");
  }
  return mqttClient.connected();
}

void mqttInit() {
  mqttClient.setServer(mqtt_server, mqtt_port);
  mqttClient.setBufferSize(1024); // Increase buffer size for large JSON payloads
  mqttClient.setCallback(mqttCallback);
}

void mqttPublishState() {
  DynamicJsonDocument jsonDoc(1024);
  String jsonResponse;
  
  uint8_t lineActiveState = isUpsPoweredFromBattery() ? 2 : isInputLinePowered() ? 1 : isUpsOn() ? 2 : 0;

  jsonDoc["success"] = 2;
  jsonDoc["on"] = powerOutputActive ? 1 : 0;
  jsonDoc["state"] = isUpsOn() ? 1 : 0;
  jsonDoc["v"] = String(batteryVoltage, 2);
  jsonDoc["batt"] = batteryLevel;
  jsonDoc["battP"] = batteryPercentage;
  jsonDoc["line"] = lineActiveState;
  jsonDoc["uptime"] = millis() / 1000;
  
  jsonDoc["auto"] = cfgAutoOn;
  jsonDoc["battBlink"] = isUpsBatteryIndicatorChargingOrBlink() ? 1 : 0;
  jsonDoc["battCritical"] = isUpsBatteryCritical() ? 1 : 0;
  jsonDoc["chargeLv"] = getRawBatteryLevelFromPercentage(batteryPercentage);
  jsonDoc["battMax"] = 4;
  jsonDoc["timedShutdown"] = (persistentShutdown && powerOutputActive) ? 1 : 0;
  jsonDoc["shutdownRemain"] = getPersistentShutdownTick() / 1000000;
  jsonDoc["shutdownSuggestMode"] = cfgShutdownSuggestion;
  jsonDoc["shutdownSuggest"] = getShutdownSuggestionFlag() ? 1 : 0;
  jsonDoc["shutLastTimer"] = cfgShutdownInSeconds;
  
  jsonDoc["chgError"] = chargeError;
  jsonDoc["charging"] = getChargingState();
  jsonDoc["chgMode"] = cfgChargeMode;
  jsonDoc["chgOVP"] = cfgChargeOvervoltageProtection;
  jsonDoc["chgReducer"] = cfgChargeAutomaticReducer;
  jsonDoc["chgFullTrig"] = cfgInputLostTriggerChargeMode;
  jsonDoc["chgOFC"] = needFullChargeOnce ? 1 : 0;

  serializeJson(jsonDoc, jsonResponse);
  mqttClient.publish(mqtt_topic_state, jsonResponse.c_str());
}

void mqttRoutine() {
  if (!mqttClient.connected()) {
    long now = millis();
    if (now - lastMqttReconnectAttempt > 5000) {
      lastMqttReconnectAttempt = now;
      // Attempt to reconnect
      if (mqttReconnect()) {
        lastMqttReconnectAttempt = 0;
      }
    }
  } else {
    mqttClient.loop();
    
    // Publish state periodically
    long now = millis();
    if (now - lastMqttPublish > mqttPublishInterval) {
      lastMqttPublish = now;
      mqttPublishState();
    }
  }
}

#endif