// @nuget: HtmlAgilityPack

// @nuget: HtmlAgilityPack -Version 1.8.2

using System;

using System.Text;

using System.Threading;

using System.Threading.Tasks;

using MQTTnet;

using MQTTnet.Client;

using MQTTnet.Client.Options;

using MQTTnet.Client.Receiving;

using MQTTnet.Extensions.ManagedClient;

class MQTTExample

{

    static async Task Main(string[] args)

    {

        var factory = new MqttFactory();

        var clientId = Guid.NewGuid().ToString();

        var managedOptions = new ManagedMqttClientOptionsBuilder()

            .WithAutoReconnectDelay(TimeSpan.FromSeconds(1))

            .WithClientOptions(new MqttClientOptionsBuilder()

                .WithTcpServer("iot.cht.com.tw", 2883)

                .WithTls()

                .WithClientId(clientId)  //自行產生

                .WithCredentials("USERNAME_IS_YOUR-API-KEY", "PASWORD_IS_YOUR-API-KEY")

                .Build())

            .Build();

        using (var client = factory.CreateManagedMqttClient())

        {

            client.UseConnectedHandler(async e =>

            {

                Console.WriteLine("Connected to MQTT broker");

                await client.SubscribeAsync(new MqttTopicFilterBuilder()

                    .WithTopic("phone-conn/calloutResult/SNKEY_TOKEN")

                    .Build());

                await client.SubscribeAsync(new MqttTopicFilterBuilder()

                    .WithTopic("phone-conn/callEvent/SNKEY_TOKEN")

                    .Build());

                await client.SubscribeAsync(new MqttTopicFilterBuilder()

                    .WithTopic("phone-conn/callActionDebug/SNKEY_TOKEN")

                    .Build());

            });

            client.UseDisconnectedHandler(async e =>

            {

                Console.WriteLine("Disconnected from MQTT broker. Reconnecting in 1 second...");

                await Task.Delay(TimeSpan.FromSeconds(1));

                await client.StartAsync(managedOptions);

            });

            client.UseApplicationMessageReceivedHandler(async e =>

            {

                var message = e.ApplicationMessage;

                var payload = Encoding.UTF8.GetString(message.Payload);

                Console.WriteLine($"Received message on topic '{message.Topic}': {payload}");

                if (message.Topic == "phone-conn/callEvent/SNKEY_TOKEN")

                {

                    var publishMessage = new MqttApplicationMessageBuilder()

                        .WithTopic("phone-conn/callAction/SNKEY_TOKEN")

                        .WithPayload(@"{

                            ""id"": ""CaYUd3gVpx"",

                            ""node"": ""getDTMFNode"",

                            ""text"": ""請按下任意數字鍵"",

                            ""repeat"": 2,

                            ""collectDTMF"": true

                        }")

                        .Build();

                    await client.PublishAsync(publishMessage);

                }

            });

            await client.StartAsync(managedOptions);

            Console.WriteLine("Press any key to exit");

            Console.ReadKey();

            await client.StopAsync();

        }

    }

}