Arduino/ESP8266-MQTT-Aten-MagicBox/ESP8266-MQTT-Aten-MagicBox.ino

/**********************************************************************
 * The MIT License (MIT)
 *
 * Copyright (c) 2015 Nis Wechselberg
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 **********************************************************************/

/**********************************************************************
 * ESP8266-MQTT-BenQ-BeamerControl
 *
 * Links the ESP8266 based serial beamer control board to an mqtt broker.
 * The program uses multiple topics for incoming and outgoing messages.
 * Incoming topics:
 * - <mqtt_device>/power
 * Outgoing topics:
 *
 **********************************************************************/

#include <ESP8266WiFi.h>
#include <ESP8266mDNS.h>
#include <WiFiUdp.h>
#include <ArduinoOTA.h>
#include <PubSubClient.h>
#include "ESP8266-MQTT-Aten-MagicBox.h"

// Timestamp for last publish
long lastMsg = 0;
long publishInterval = 5000;

// Global mqtt client object
WiFiClient espClient;
PubSubClient client(espClient);

/*
 * Initial setup for arduino
 */
void setup() {
  // Configure serial port
  Serial.begin(19200);
  delay(10);

  // Prepare WiFi connection
  setup_wifi();

  // Connect to mqtt broker
  client.setServer(mqtt_server, 1883);
  client.setCallback(incoming_mqtt);
}

/*
 * Prepares the wireless connection
 */
void setup_wifi() {
  // Connect to the WiFi as a client
  WiFi.mode(WIFI_STA);

  // Do the connection
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }
  ArduinoOTA.setHostname(ota_hostname);
  ArduinoOTA.setPassword(ota_hostname);
  ArduinoOTA.begin();  
}

/*
 * Callback method for incoming mqtt messages
 */
void incoming_mqtt(char* topic, byte* payload, unsigned int length) {
  if (strcmp(topic, mqtt_topic_port) == 0) {
    if (length == 1) {
      // Select the port
      Serial.print("\rsw i0");
      Serial.print((char)payload[0]);
      Serial.print("\r");
    }
  }
}

/*
 * Blocking reconnect to the mqtt broker
 */
void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    // Attempt to connect
    if (client.connect(mqtt_device)) {
      // subscribe to incoming topics
      client.subscribe(mqtt_topic_port);
    } else {
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void clearSerialInput() {
  while(Serial.available() > 0) {
    char t = Serial.read();
  }
}

void updateState() {
  Serial.print("\r");
  delay(250);
  // Clean input buffer
  clearSerialInput();

  // Write request to serial
  Serial.print("read\r");
  delay(250);

  // Extract lamp time from response
  String message = Serial.readString();
  
  int startIndex = message.lastIndexOf("Input:port");
  if (startIndex != -1) {
    String state = message.substring(startIndex + 11, startIndex + 12);
    char buffer[2];
    state.toCharArray(buffer, 2);
    client.publish(mqtt_topic_portState, buffer);
  }
}

void loop() {
  // Check OTA update
  ArduinoOTA.handle();
  
  // Ensure MQTT connection
  if (!client.connected()) {
    reconnect();
  }

  // Check the inbox
  client.loop();

  // Maybe push the current status
  long now = millis();
  if (now - lastMsg > publishInterval) {
    lastMsg = now;
    updateState();
  }
}