using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tango.Core.DI;
using Tango.FSE.Common;
using Tango.FSE.Common.FileAssociation;
using Tango.FSE.Common.FSEApplication;
using Tango.FSE.Common.Threading;
using Tango.Logging;
using ZetaIpc.Runtime.Server;

namespace Tango.FSE.UI.FileAssociation
{
    [TangoCreateWhenRegistered]
    public class DefaultFileAssociationProvider : FSEExtendedObject, IFileAssociationProvider
    {
        private Dictionary<String, Action<FileAssociationPackage>> _handlers;
        private IpcServer _ipcServer;
        private bool _initialized;

        public const string FILE_ASSOCIATION_PREFIX = "-file";
        public const int FILE_ASSOCIATION_ARGS_COUNT = 3;

        public bool HasStartArgsPackage { get; private set; }

        [TangoInject]
        private IDispatcherProvider DispatcherProvider { get; set; }

        [TangoInject]
        private IFSEApplicationManager ApplicationManager { get; set; }

        public DefaultFileAssociationProvider()
        {
            _handlers = new Dictionary<string, Action<FileAssociationPackage>>();
            _ipcServer = new IpcServer();
        }

        public void RegisterFileAssociationHandler(string targetName, Action<FileAssociationPackage> handler)
        {
            _handlers.Add(targetName.ToLower(), handler);
        }

        public async void OnApplicationReady(IFSEApplicationManager applicationManager)
        {
            if (_initialized) return;

            _initialized = true;

            try
            {
                LogManager.Log("Starting file association IPC service...");
                _ipcServer.Start(Settings.FileAssociationServicePort);
                _ipcServer.ReceivedRequest += _ipcServer_ReceivedRequest;
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, "Error starting file association IPC service. Another instance of the application might already be running...");
            }

            var args = applicationManager.StartupArgs;

            LogManager.Log("Processing file association if any...");

            if (args.Count == FILE_ASSOCIATION_ARGS_COUNT)
            {
                if (args[0] == FILE_ASSOCIATION_PREFIX)
                {

                    //This delay is a workaround for when the invoked handler navigates to some module.
                    //The navigation system does not catches the navigation request properly... :/
                    await Task.Delay(500);

                    LogManager.Log($"File association package found: '{String.Join(" ", args)}'. Invoking handler...");

                    try
                    {
                        String targetName = args[1].ToLower();

                        if (_handlers.ContainsKey(targetName))
                        {
                            var package = new FileAssociationPackage()
                            {
                                TargetName = targetName,
                                File = args[2]
                            };

                            _handlers[targetName].Invoke(package);
                        }
                        else
                        {
                            LogManager.Log("File association handler not found.", LogCategory.Warning);
                        }
                    }
                    catch (Exception ex)
                    {
                        LogManager.Log(ex, $"Error invoking file association handler for package '{String.Join(" ", args)}'.");
                    }
                }
            }
        }

        private void _ipcServer_ReceivedRequest(object sender, ReceivedRequestEventArgs e)
        {
            try
            {
                e.Handled = true;
                LogManager.Log($"File association package received through IPC server.\n{e.Request}\nInvoking handler...");

                var package = JsonConvert.DeserializeObject<FileAssociationPackage>(e.Request);

                if (_handlers.ContainsKey(package.TargetName.ToLower()))
                {
                    DispatcherProvider.Invoke(() =>
                    {
                        if (ApplicationManager.WindowState == System.Windows.WindowState.Minimized)
                        {
                            ApplicationManager.WindowState = System.Windows.WindowState.Normal;
                        }
                        ApplicationManager.ActivateMainWindow();
                        _handlers[package.TargetName.ToLower()].Invoke(package);
                    });
                }
                else
                {
                    LogManager.Log($"Handler not found for target '{package.TargetName}'.", LogCategory.Warning);
                }
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, $"Error invoking file association handler.");
            }
        }

        public void OnApplicationStarted(IFSEApplicationManager applicationManager)
        {
            HasStartArgsPackage =
                applicationManager.StartupArgs.Count == FILE_ASSOCIATION_ARGS_COUNT
                &&
                applicationManager.StartupArgs[0] == FILE_ASSOCIATION_PREFIX;
        }
    }
}