using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.Windows.Input;
using RGBController2.Commands;
using RGBController2.ViewModels.Tabs;
using RGBController2.ViewModels.Dialogs;
using System.ComponentModel;
using System.Windows;
using System.Xml;
using System.IO;
using System.Linq;

namespace RGBController2.ViewModels
{
    class MainViewModel
    {

        /// <summary>
        /// This is the directory of the exe
        /// </summary>
        public static string BaseDir = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);

        private readonly ObservableCollection<Tab> _tabs;
        public ICommand NewTabCommand { get; }
        public static ICollection<Tab> Tabs { get; set; }

        private string configLocation = "config.xml";

        private bool _runOnStartUp;

        public bool RunOnStartUp
        {
            get { return _runOnStartUp; }
            set 
            {
                if (value != _runOnStartUp)
                {
                    _runOnStartUp = value;
                    RunAppOnStartup(value);
                }
            }
        }

        public MainViewModel()
        {
            configLocation = Path.Combine(BaseDir, "config.xml");
            NewTabCommand = new ActionCommand(p => NewTab());

            _tabs = new ObservableCollection<Tab>();
            _tabs.CollectionChanged += Tabs_CollectionChanged;

            Tabs = _tabs;

            _runOnStartUp = IsRunAppOnStartup();

            // Check here that the config file exists
            if (File.Exists(configLocation))
            {
                // Load the config file
                using (XmlReader reader = XmlReader.Create(configLocation))
                {
                    string name = "";
                    string type = "";
                    string device = "";

                    while (reader.Read())
                    {
                        if (reader.IsStartElement())
                        {
                            //return only when you have START tag  
                            switch (reader.Name.ToString())
                            {
                                case "name":
                                    name = reader.ReadString();
                                    break;
                                case "type":
                                    type = reader.ReadString();
                                    break;
                                case "device":
                                    device = reader.ReadString();
                                    break;
                            }
                        }
                        // Create the tab here
                        if (name != "" && type != "" && device !="")
                        {
                            switch (type)
                            {
                                case "arduino":
                                    {
                                        var tab = new ArduinoTab(name);
                                        tab.SelectedPort = device;
                                        _tabs.Add(tab);
                                        break;
                                    }
                                case "cue":
                                    {
                                        var tab = new CueDeviceTab(name);
                                        switch (device)
                                        {
                                            case "Headset":
                                                tab.SelectedDevice = CUE.NET.Devices.Generic.Enums.CorsairDeviceType.Headset;
                                                break;
                                            case "HeadsetStand":
                                                tab.SelectedDevice = CUE.NET.Devices.Generic.Enums.CorsairDeviceType.HeadsetStand;
                                                break;
                                            case "Keyboard":
                                                tab.SelectedDevice = CUE.NET.Devices.Generic.Enums.CorsairDeviceType.Keyboard;
                                                break;
                                            case "Mouse":
                                                tab.SelectedDevice = CUE.NET.Devices.Generic.Enums.CorsairDeviceType.Mouse;
                                                break;
                                            case "Mousemat":
                                                tab.SelectedDevice = CUE.NET.Devices.Generic.Enums.CorsairDeviceType.Mousemat;
                                                break;
                                        }

                                        _tabs.Add(tab);
                                        break;
                                    }
                            }

                            name = "";
                            type = "";
                            device = "";
                        }
                    }
                }
            }
        }

        private void Tabs_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
        {
            ITab tab;

            switch (e.Action)
            {
                case NotifyCollectionChangedAction.Add:
                    tab = (ITab) e.NewItems[0];
                    tab.CloseRequested += OnTabCloseRequested;
                    break;
                case NotifyCollectionChangedAction.Remove:
                    tab = (ITab) e.OldItems[0];
                    tab.CloseRequested -= OnTabCloseRequested;
                    break;
            }
          
        }

        private void OnTabCloseRequested(object sender, EventArgs e)
        {
            Tabs.Remove((Tab) sender);
        }

        private void NewTab()
        {
            // Open the add tab dialog
            var dialog = new NewTabDialogViewModel();
            dialog.ShowDialogWindow();

            // Use the results from the dialog when creating the new tab
            if (dialog.Success)
            {
                switch(dialog.SelectedDeviceType)
                {
                    case 0: // Arduino
                        Tabs.Add(new ArduinoTab(dialog.DeviceName));
                        break;
                    case 1:
                        Tabs.Add(new CueDeviceTab(dialog.DeviceName));
                        break;
                }
            }
        }

        /// <summary>
        /// This function is called when the application is closed.
        /// This allows the configuration to be saved to disk.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void OnWindowClosing(object sender, CancelEventArgs e)
        {
            // Check if the config file currently exists
            // if it does then we will need to delete it beofre we can save a new config
            if (File.Exists(configLocation))
            {
                File.Delete(configLocation);
            }

            // This may need to be saved somwhere better, for now we will just save it
            // with the executable
            XmlWriter xmlWriter = XmlWriter.Create(configLocation);
            xmlWriter.WriteStartDocument();

            xmlWriter.WriteStartElement("tabs");
            xmlWriter.WriteAttributeString("count", Tabs.Count.ToString());
            foreach (var tab in Tabs)
            {
                xmlWriter.WriteStartElement("tab");
                xmlWriter.WriteStartElement("name");
                xmlWriter.WriteString(tab.Name);
                xmlWriter.WriteEndElement();

                switch (tab.TabType)
                {
                    case Tab.tabType.Arduino:
                        xmlWriter.WriteStartElement("type");
                        xmlWriter.WriteString("arduino");
                        xmlWriter.WriteEndElement();
                        xmlWriter.WriteStartElement("device");
                        xmlWriter.WriteString(((ArduinoTab)tab).SelectedPort);
                        xmlWriter.WriteEndElement();
                        break;
                    case Tab.tabType.CUE:
                        xmlWriter.WriteStartElement("type");
                        xmlWriter.WriteString("cue");
                        xmlWriter.WriteEndElement();
                        xmlWriter.WriteStartElement("device");
                        xmlWriter.WriteString(((CueDeviceTab)tab).SelectedDevice.ToString());
                        xmlWriter.WriteEndElement();
                        break;
                }
                xmlWriter.WriteEndElement();
            }

            xmlWriter.WriteEndDocument();
            xmlWriter.Close();
        }

        /// <summary>
        /// Checks if run on startup is enabled in the registry for the current user.
        /// </summary>
        /// <returns>Truw if run on startup is enabled, false if not</returns>
        private bool IsRunAppOnStartup()
        {
            Microsoft.Win32.RegistryKey key = Microsoft.Win32.Registry.CurrentUser.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);
            return key.GetValueNames().Contains("RGB Application");
        }

        /// <summary>
        /// Helper function for modifying the registry to enable/disable run on startup.
        /// This only enables run on startup for the current user, not the whole machine.
        /// </summary>
        /// <param name="enabled">True if should be enabled, false if should be disabled.</param>
        private void RunAppOnStartup(bool enabled)
        {
            if (enabled)
            {
                Microsoft.Win32.RegistryKey key = Microsoft.Win32.Registry.CurrentUser.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);
                key.SetValue("RGB Application", Path.Combine(BaseDir, System.AppDomain.CurrentDomain.FriendlyName) + ".exe");
            }
            else
            {
                Microsoft.Win32.RegistryKey key = Microsoft.Win32.Registry.CurrentUser.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);
                key.DeleteValue("RGB Application", false);
            }
        }
    }
}