text: /**
   * Copyright (c) 2017, Arm Limited and affiliates.
   * SPDX-License-Identifier: Apache-2.0
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  #include <stdio.h>
  
  #include "lorawan/LoRaWANInterface.h"
  #include "lorawan/system/lorawan_data_structures.h"
  #include "events/EventQueue.h"
  
  // Application helpers
  #include "DummySensor.h"
  #include "trace_helper.h"
  #include "lora_radio_helper.h"
  
  // CayenneLPP lib for packaging sensor data
  #include "CayenneLPP.h"
  
  using namespace events;
  
  // Max payload size can be LORAMAC_PHY_MAXPAYLOAD.
  // This example only communicates with much shorter messages (<30 bytes).
  // If longer messages are used, these buffers must be changed accordingly.
  uint8_t tx_buffer[10];
  uint8_t rx_buffer[10];
  
  /*
   * Sets up an application dependent transmission timer in ms. Used only when Duty Cycling is off for testing
   */
  #define TX_TIMER                        10000
  
  /**
   * Maximum number of events for the event queue.
   * 10 is the safe number for the stack events, however, if application
   * also uses the queue for whatever purposes, this number should be increased.
   */
  #define MAX_NUMBER_OF_EVENTS            8
  
  /**
   * Maximum number of retries for CONFIRMED messages before giving up
   */
  #define CONFIRMED_MSG_RETRY_COUNTER     3
  
  /**
   * Dummy pin for dummy sensor
   */
  #define PC_9                            0
  
  /**
   * Dummy sensor class object
   */
  DS1820  ds1820(PC_9);
  
  /**
  * This event queue is the global event queue for both the
  * application and stack. To conserve memory, the stack is designed to run
  * in the same thread as the application and the application is responsible for
  * providing an event queue to the stack that will be used for ISR deferment as
  * well as application information event queuing.
  */
  static EventQueue ev_queue(MAX_NUMBER_OF_EVENTS *EVENTS_EVENT_SIZE);
  
  /**
   * Event handler.
   *
   * This will be passed to the LoRaWAN stack to queue events for the
   * application which in turn drive the application.
   */
  static void lora_event_handler(lorawan_event_t event);
  
  /**
   * Constructing Mbed LoRaWANInterface and passing it the radio object from lora_radio_helper.
   */
  static LoRaWANInterface lorawan(radio);
  
  /**
   * Application specific callbacks
   */
  static lorawan_app_callbacks_t callbacks;
  
  /**
   * Entry point for application
   */
  int main(void)
  {
  
     // setup tracing
      setup_trace();
  
      // stores the status of a call to LoRaWAN protocol
      lorawan_status_t retcode;
  
      // Initialize LoRaWAN stack
      if (lorawan.initialize(&ev_queue) != LORAWAN_STATUS_OK) {
          printf("\r\n LoRa initialization failed! \r\n");
          return -1;
      }
  
      printf("\r\n\r\n\r\n\r\n Mbed LoRaWANStack initialized");
  
      // prepare application callbacks
      callbacks.events = mbed::callback(lora_event_handler);
      lorawan.add_app_callbacks(&callbacks);
  
      // Set number of retries in case of CONFIRMED messages
      if (lorawan.set_confirmed_msg_retries(CONFIRMED_MSG_RETRY_COUNTER)
              != LORAWAN_STATUS_OK) {
          printf("\r\n set_confirmed_msg_retries failed! \r\n\r\n");
          return -1;
      }
  
      printf("\r\n CONFIRMED message retries : %d",
             CONFIRMED_MSG_RETRY_COUNTER);
  
      // Enable adaptive data rate
      if (lorawan.enable_adaptive_datarate() != LORAWAN_STATUS_OK) {
          printf("\r\n enable_adaptive_datarate failed! \r\n");
          return -1;
      }
  
      printf("\r\n Adaptive data  rate (ADR) - Enabled");
  
      retcode = lorawan.connect();
  
      if (retcode == LORAWAN_STATUS_OK ||
              retcode == LORAWAN_STATUS_CONNECT_IN_PROGRESS) {
      } else {
          printf("\r\n Connection error, code = %d \r\n", retcode);
          return -1;
      }
  
      printf("\r\n Connection - In Progress ...\r\n");
  
      // make your event queue dispatching events forever
      ev_queue.dispatch_forever();
  
      return 0;
  }
  
  /**
   * Sends a message to the Network Server
   */
  static void send_message()
  {
      uint16_t packet_len;
      int16_t retcode;
      float sensor_value;
  
      if (ds1820.begin()) {
          ds1820.startConversion();
          sensor_value = ds1820.read();
          printf("Dummy Sensor Value = %3.1f\r\n", sensor_value);
          ds1820.startConversion();
      } else {
          printf("\r\n No sensor found \r\n");
          return;
      }
  
      packet_len = sprintf((char *) tx_buffer, "%3.1f",
                           sensor_value);
      
  //create a caynennelpp payload, max 10bytes
      CayenneLPP payload(10);
      payload.addTemperature(1,sensor_value); 
  
      retcode = lorawan.send(MBED_CONF_LORA_APP_PORT, payload.getBuffer(), payload.getSize(),
                             MSG_UNCONFIRMED_FLAG);
  
      if (retcode < 0) {
          retcode == LORAWAN_STATUS_WOULD_BLOCK ? printf("send - WOULD BLOCK\r\n")
          : printf("\r\n send() - Error code %d \r\n", retcode);
  
          if (retcode == LORAWAN_STATUS_WOULD_BLOCK) {
              //retry in 3 seconds
              if (MBED_CONF_LORA_DUTY_CYCLE_ON) {
                  ev_queue.call_in(3000, send_message);
              }
          }
          return;
      }
  
      printf(" %d bytes scheduled for transmission\r\n", retcode);
      memset(tx_buffer, 0, sizeof(tx_buffer));
  }
  
  /**
   * Receive a message from the Network Server
   */
  static void receive_message()
  {
      uint8_t port;
      int flags;
      int16_t retcode = lorawan.receive(rx_buffer, sizeof(rx_buffer), port, flags);
  
      if (retcode < 0) {
          printf("\r\n receive() - Error code %d \r\n", retcode);
          return;
      }
  
      printf(" RX Data on port %u (%d bytes): ", port, retcode);
      for (uint8_t i = 0; i < retcode; i++) {
          printf("%02x ", rx_buffer[i]);
      }
      printf("\r\n");
      
      memset(rx_buffer, 0, sizeof(rx_buffer));
  }
  
  /**
   * Event handler
   */
  static void lora_event_handler(lorawan_event_t event)
  {
      switch (event) {
          case CONNECTED:
              printf("\r\n Connection - Successful \r\n");
              if (MBED_CONF_LORA_DUTY_CYCLE_ON) {
                  send_message();
              } else {
                  ev_queue.call_every(TX_TIMER, send_message);
              }
  
              break;
          case DISCONNECTED:
              ev_queue.break_dispatch();
              printf("\r\n Disconnected Successfully \r\n");
              break;
          case TX_DONE:
              printf("Message Sent to Network Server\r\n");
              if (MBED_CONF_LORA_DUTY_CYCLE_ON) {
                  send_message();
              }
              break;
          case TX_TIMEOUT:
          case TX_ERROR:
          case TX_CRYPTO_ERROR:
          case TX_SCHEDULING_ERROR:
              printf("\r\n Transmission Error - EventCode = %d \r\n", event);
              // try again
              if (MBED_CONF_LORA_DUTY_CYCLE_ON) {
                  send_message();
              }
              break;
          case RX_DONE:
              printf("\r\n Received message from Network Server \r\n");
              receive_message();
              break;
          case RX_TIMEOUT:
          case RX_ERROR:
              printf("\r\n Error in reception - Code = %d \r\n", event);
              break;
          case JOIN_FAILURE:
              printf("\r\n OTAA Failed - Check Keys \r\n");
              break;
          case UPLINK_REQUIRED:
              printf("\r\n Uplink required by NS \r\n");
              if (MBED_CONF_LORA_DUTY_CYCLE_ON) {
                  send_message();
              }
              break;
          default:
              MBED_ASSERT("Unknown Event");
      }
  }
  
  // EOF
  