using Edge.Core.Processor;
using Edge.Core.IndustryStandardInterface.Pump;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using MQTTnet;
using MQTTnet.Client;
using MQTTnet.Diagnostics;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Printing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace XinHua_XPrinter_WindowsPrinter_App
{
    public class App : IAppProcessor
    {
        private ILogger logger = new LoggerFactory().CreateLogger("no exists");
        private IMqttClient mqttClient;

        private string mqttServerUrl;
        private int mqttServerPort;
        private string mqttClientId;
        private string mqttClientUsername;
        private string mqttClientPassword;

        private string topic_PrintingRequest;
        private string topic_PrintRequestReply;
        private string printerName;

        private string printingContent;

        private bool shouldReconnect = true;

        public string MetaConfigName { get; set; }

        public App(string mqttServerUrl, int mqttServerPort, string mqttClientId,
            string mqttClientUsername, string mqttClientPassword,
            string topic_PrintingRequest, string topic_PrintRequestReply, string printerName, IServiceProvider services)
        {
            if (services != null)
            {
                var loggerFactory = services.GetRequiredService<ILoggerFactory>();
                this.logger = loggerFactory.CreateLogger("Application");
            }

            this.mqttServerUrl = mqttServerUrl;
            this.mqttServerPort = mqttServerPort;
            this.mqttClientId = mqttClientId;
            this.mqttClientUsername = mqttClientUsername;
            this.mqttClientPassword = mqttClientPassword;

            this.topic_PrintingRequest = topic_PrintingRequest;
            this.topic_PrintRequestReply = topic_PrintRequestReply;
            this.printerName = printerName;
        }

        public async void Init(IEnumerable<IProcessor> processors)
        {
            //https://docs.microsoft.com/en-us/dotnet/api/system.drawing.graphics.drawstring?view=netcore-3.0
            PrintDocument printDocument = new PrintDocument();
            var installedPrinters = PrinterSettings.InstalledPrinters.Cast<string>();
            this.logger.LogInformation("System installed printers are: "
                + installedPrinters.Aggregate((acc, n) => acc + ", " + n)
                + Environment.NewLine
                + "now the printer with name: " + printDocument.PrinterSettings.PrinterName + " is defaultly chosen.");
            if (!string.IsNullOrEmpty(this.printerName))
            {
                this.logger.LogInformation("    will switch to printer with name: " + this.printerName);
                printDocument.PrinterSettings.PrinterName = this.printerName;
            }

            printDocument.PrintPage += Pd_PrintPage;

            //MqttNetGlobalLogger.LogMessagePublished += (s, e) =>
            //{
            //    //var trace = $">> [{e.TraceMessage.ThreadId}] [{e.TraceMessage.Source}] [{e.TraceMessage.Level}]: {e.TraceMessage.Message}";
            //    if (this.logger.IsEnabled(LogLevel.Trace))
            //    {
            //        var trace = $"MQTTnet - {e.TraceMessage.Message}";
            //        if (e.TraceMessage.Exception != null)
            //            trace += Environment.NewLine + e.TraceMessage.Exception.ToString();
            //        this.logger.LogTrace(trace);
            //    }
            //};
            // Create a new MQTT client.
            var factory = new MqttFactory();
            this.mqttClient = factory.CreateMqttClient();
            this.mqttClient.ApplicationMessageReceivedAsync += e =>
            {
                if (this.logger.IsEnabled(LogLevel.Trace))
                {
                    this.logger.LogTrace("### Received Messages from Topic ###");
                    this.logger.LogTrace($"     Topic = {e.ApplicationMessage.Topic}");
                    this.logger.LogTrace($"     Payload = {Encoding.UTF8.GetString(e.ApplicationMessage.Payload)}");
                    this.logger.LogTrace($"     QoS = {e.ApplicationMessage.QualityOfServiceLevel}");
                    this.logger.LogTrace($"     Retain = {e.ApplicationMessage.Retain}");
                }

                if (e.ApplicationMessage.Topic == this.topic_PrintingRequest)
                {
                    this.printingContent = this.ParseToPrinterStringData(e.ApplicationMessage.Payload);
                    printDocument.Print();
                    if (!string.IsNullOrEmpty(this.topic_PrintRequestReply))
                        this.mqttClient.PublishAsync(new MqttApplicationMessage()
                        {
                            Topic = this.topic_PrintRequestReply,
                            Payload = new byte[] { }
                        });
                }

                return Task.CompletedTask;
            };
            this.mqttClient.DisconnectedAsync += arg =>
            {
                this.shouldReconnect = true;
                this.logger.LogInformation("    Mqtt connection disconnected, " +
                    "AuthenticateResult: " + (arg.ReasonString ?? "") +
                    ", ClientWasConnected: " + arg.ClientWasConnected +
                    ", exception: " + arg.Exception);
                return Task.CompletedTask;
            };
            // Create TCP based options using the builder.
            var options = new MqttClientOptionsBuilder()
                .WithClientId(this.mqttClientId)
                .WithTcpServer(this.mqttServerUrl, this.mqttServerPort)
                .WithCredentials(this.mqttClientUsername, this.mqttClientPassword)
                .WithKeepAlivePeriod(new TimeSpan(0, 0, 30))
                .WithCleanSession(true)
                .Build();
            await Task.Run(async () =>
            {
                while (true)
                {
                    if (!this.shouldReconnect) { await Task.Delay(30000); continue; }
                    this.logger.LogDebug("Connecting to mqtt server...");
                    try
                    {
                        try
                        {
                            // always try to close previous conn.
                            await mqttClient.DisconnectAsync();
                        }
                        catch { }

                        var result = await mqttClient.ConnectAsync(options);
                        if (result.ResultCode == MqttClientConnectResultCode.Success)
                        {
                            this.logger.LogInformation("    Successfully connected to mqtt server.");
                            var subResult = await this.mqttClient.SubscribeAsync(this.topic_PrintingRequest,
                                MQTTnet.Protocol.MqttQualityOfServiceLevel.AtMostOnce);
                            if (subResult.Items.Any())
                            {
                                if ((int)(subResult.Items.First().ResultCode) <= 2)
                                {
                                    this.logger.LogInformation("    Successfully subscribed on topic.");
                                    this.shouldReconnect = false;
                                }
                                else
                                {
                                    this.logger.LogInformation("    Failed on subscribe on topic with Sub resultCode: "
                                        + subResult.Items.First().ResultCode);
                                }
                            }
                            else
                                this.logger.LogInformation("    Failed on subscribe on topic by generic error.");
                        }
                        else
                        {
                            this.logger.LogInformation("    Failed connecting to mqtt server with returned ResultCode: "
                                + result.ResultCode
                                + ", ReasonString:" + (result.ReasonString ?? ""));
                        }
                    }
                    catch (Exception exx)
                    {
                        this.logger.LogError("  Connecting to mqtt server exceptioned: " + exx);
                    }

                }
            });
        }

        private void Pd_PrintPage(object sender, PrintPageEventArgs e)
        {
            //string drawString = "hello world this is my test line0"
            //    + Environment.NewLine + "line1"
            //    + Environment.NewLine + "line2";
            // Create font and brush.
            Font drawFont = new Font("Arial", 10);//, FontStyle.Bold);
            SolidBrush drawBrush = new SolidBrush(Color.Black);

            // Create point for upper-left corner of drawing.
            float x = 0.00F;
            float y = 0.00F;

            // Set format of string.
            StringFormat drawFormat = new StringFormat();
            //drawFormat.FormatFlags = StringFormatFlags.DirectionVertical;
            //drawFormat.FormatFlags = StringFormatFlags.DisplayFormatControl;
            e.Graphics.DrawString(this.printingContent, drawFont, drawBrush, x, y, drawFormat);

            //e.Graphics.DrawString("\x1b\x69", drawFont, drawBrush, x, y + 40, drawFormat);

            //string GS = Convert.ToString((char)29);
            //string ESC = Convert.ToString((char)27);
            //string COMMAND = "";
            //COMMAND = ESC + "@";
            //COMMAND += GS + "V" + (char)1;
            //e.Graphics.DrawString(COMMAND, drawFont, drawBrush, x, y + 60, drawFormat);

            //e.Graphics.DrawString("\x1B@\x1DV1", drawFont, drawBrush, x, y + 80, drawFormat);
        }

        public async Task<bool> Start()
        {
            return true;
        }

        public async Task<bool> Stop()
        {
            return true;
        }

        /// <summary>
        /// parse the bytes from remote which most likely with format control chars included.
        /// </summary>
        /// <param name="remoteContent"></param>
        /// <returns>a string that the device can read and operate</returns>
        private string ParseToPrinterStringData(byte[] rawContent)
        {
            return Encoding.UTF8.GetString(rawContent);
        }
    }
}