/*
 * Copyright 2010-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file 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 <aws_iot_mqtt.h>
#include <aws_iot_version.h>
#include "aws_iot_config.h"

aws_iot_mqtt_client myClient; // init iot_mqtt_client
char msg[32]; // read-write buffer
int cnt = 0; // loop counts
int rc = -100; // return value placeholder
bool success_connect = false; // whether it is connected

// Basic callback function that prints out the message
void msg_callback(char* src, unsigned int len, Message_status_t flag) {
  if(flag == STATUS_NORMAL) {
    Serial.println("CALLBACK:");
    int i;
    for(i = 0; i < (int)(len); i++) {
      Serial.print(src[i]);
    }
    Serial.println("");
  }
}

void setup() {
  // Start Serial for print-out and wait until it's ready
  Serial.begin(115200);
  while(!Serial);
  //
  char curr_version[80];
  snprintf_P(curr_version, 80, PSTR("AWS IoT SDK Version(dev) %d.%d.%d-%s\n"), VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH, VERSION_TAG);
  Serial.println(curr_version);
  // Set up the client
  if((rc = myClient.setup(AWS_IOT_CLIENT_ID)) == 0) {
    // Load user configuration
    if((rc = myClient.config(AWS_IOT_MQTT_HOST, AWS_IOT_MQTT_PORT, AWS_IOT_ROOT_CA_PATH, AWS_IOT_PRIVATE_KEY_PATH, AWS_IOT_CERTIFICATE_PATH)) == 0) {
      // Use default connect: 60 sec for keepalive
      if((rc = myClient.connect()) == 0) {
        success_connect = true;
        // Subscribe to "topic1"
        if((rc = myClient.subscribe("topic1", 1, msg_callback)) != 0) {
          Serial.println("Subscribe failed!");
          Serial.println(rc);
        }
      }
      else {
        Serial.println(F("Connect failed!"));
        Serial.println(rc);
      }
    }
    else {
      Serial.println(F("Config failed!"));
      Serial.println(rc);
    }
  }
  else {
    Serial.println(F("Setup failed!"));
    Serial.println(rc);
  }
  // Delay to make sure SUBACK is received, delay time could vary according to the server
  delay(2000);
}

void loop() {
  if(success_connect) {
    // Generate a new message in each loop and publish to "topic1"
    sprintf(msg, "new message %d", cnt);
    if((rc = myClient.publish("topic1", msg, strlen(msg), 1, false)) != 0) {
      Serial.println(F("Publish failed!"));
      Serial.println(rc);
    }
  
    // Get a chance to run a callback
    if((rc = myClient.yield()) != 0) {
      Serial.println("Yield failed!");
      Serial.println(rc);
    }
  
    // Done with the current loop
    sprintf_P(msg, PSTR("loop %d done"), cnt++);
    Serial.println(msg);
  
    delay(1000);
  }
}