using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using OutputServiceTSDB.Utilities;
using Microsoft.Extensions.Logging;
using System.Threading.Tasks;
using OutputServiceTSDB.InfluxDB;
using OutputServiceTSDB.Models;
using Newtonsoft.Json;
using System;

namespace OutputServiceTSDB.RabbitMQ
{
    public class RabbitMQWorker : IDisposable
    {
        private readonly ILogger _logger;
        private IConnection _connection;
        private IModel _channel;
        private InfluxWriter influxWriter;

        public RabbitMQWorker(ILogger<RabbitMQWorker> logger)
        {
            _logger = logger;
            influxWriter = new InfluxWriter();
            InitRabbitMQ();
        }

        private void InitRabbitMQ()
        {
            var factory = new ConnectionFactory { HostName = EnvironmentVariableConfiguration.RabbitMQHostname, UserName = EnvironmentVariableConfiguration.RabbitMQUserName, Password = EnvironmentVariableConfiguration.RabbitMQPassword };

            _connection = factory.CreateConnection();

            _channel = _connection.CreateModel();

            _channel.ExchangeDeclare(EnvironmentVariableConfiguration.RabbitMQExchange, ExchangeType.Topic);
            _channel.QueueDeclare(EnvironmentVariableConfiguration.RabbitMQQueue, false, false, false, null);
            _channel.QueueBind(EnvironmentVariableConfiguration.RabbitMQQueue, EnvironmentVariableConfiguration.RabbitMQExchange, null, null);
            _channel.BasicQos(0, 1, false);
        }

        public void ProcessMessages()
        {
            var consumer = new AsyncEventingBasicConsumer(_channel);
            consumer.Received += HandleMessage;

            _channel.BasicConsume("demo.queue.log", false, consumer);
        }

        private async Task HandleMessage(object sender, BasicDeliverEventArgs @event)
        {
            var content = System.Text.Encoding.UTF8.GetString(@event.Body);
            _logger.LogInformation($"received {content}");
            MeasurementObject measurementObject = JsonConvert.DeserializeObject<MeasurementObject>(content);
            await Task.Run(() => influxWriter.Write(measurementObject));
        }

        public void Dispose()
        {
            _channel.Close();
            _connection.Close();
            influxWriter.Dispose();
        }
    }
}