using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Windows.Forms;
using Yaulw.Thread;
using System.Timers;

namespace Yaulw.WinForms
{       
    /// <remarks>
    /// Wrapper Class around .Net NotifyIcon, to make it easier to work with an System Tray Icon.
    /// Use the InitializeContextMenu Callback to create the ContextMenu.
    /// Subscripe to the MouseLeftClick, and MouseLeftDoubleClick event to get accurate events to handle,
    /// Call Show()/Hide() to show/hide the System Tray Icon, respectively.
    /// </remarks>
    public class SysTray : IDisposable
    {
        #region Public States 

        /// <summary>
        /// Allow caller to specify multipe states to show for the tray icon
        /// </summary>
        public struct TrayState
        {
            string nameOfState;
            string toolTip;
            Icon icon;                        
        }

        // keep track of added States
        private List<TrayState> _states = new List<TrayState>();

        /// <summary>
        /// Add a possible state to the collection of tray icon states
        /// </summary>
        /// <param name="state"></param>
        public void AddState(TrayState state)
        {
            _states.Add(state);
        }

        #endregion

        #region Public Properties

        /// <summary>
        /// Get/Set the Icon to show on the System Tray Notification
        /// </summary>
        public Icon Icon { get { return trayNotify.Icon; } set { trayNotify.Icon = value; } }

        /// <summary>
        /// Get/Set ToolTip to show over System Tray Notification
        /// </summary>
        public string toolTip { get { return trayNotify.Text; } set { trayNotify.Text = value; } }

        /// <summary>
        /// Is System Tray Notification Visible?
        /// </summary>
        public bool IsVisible { get { return trayNotify.Visible; } } 

        #endregion

        #region Private Properties

        private NotifyIcon trayNotify { get; set; }
        private ContextMenu trayMenu { get { return trayNotify.ContextMenu; } set { trayNotify.ContextMenu = value; } }
        private ContextMenuStrip trayMenuStrip { get { return trayNotify.ContextMenuStrip; } set { trayNotify.ContextMenuStrip = value; } } 

        #endregion

        #region Public Events

        /// <summary>
        /// System Tray Left Mouse Click Delegate
        /// </summary>
        /// <param name="e">MouseEventArgs</param>
        public delegate void SingleLeftMouseClick(MouseEventArgs e);

        /// <summary>
        /// Subscribe to get the Left Mouse Single Click Event
        /// </summary>
        public event SingleLeftMouseClick LeftMouseClick;

        /// <summary>
        /// System Tray Left Mouse Double Click Delegate
        /// </summary>
        /// <param name="e">MouseEventArgs</param>
        public delegate void DoubleLeftMouseClick(MouseEventArgs e);

        /// <summary>
        /// Subscribe to get the Left Mouse Double Click Event
        /// </summary>
        public event DoubleLeftMouseClick LeftMouseDoubleClick;
        
        /// <summary>
        /// Initialize Context Menu Dynamically Call-back * i.e. On every Right Click *
        /// Allows the Context Menu to change depending on application state
        /// </summary>
        /// <param name="trayMenuStrip">Expected a new ContextMenuStrip to Display</param>
        /// <param name="MenuClickEventHandler">Event Handle to handle Menu Click Events</param>
        public delegate void InitializeContextMenu(out ContextMenuStrip trayMenuStrip, out EventHandler MenuClickEventHandler);

        #endregion

        #region Private Members

        private InitializeContextMenu _ContextMenuInitializer = null;
        private TTimerDisp SingleClickDetectTimer = null;
        private TimeSpan _LastFiredEvent = new TimeSpan(DateTime.Now.Ticks);
        private const int _MILISECONDS_FOR_SINGLEMOUSE_CLICKEVENT_TOCOUNT = 350;
        private const int _N_SECONDS_TOIGNORE_NEXT_SIGNLEMOUSE_CLICKEVENT = 2; // to avoid tripple clicks, etc... (only sends one double click)
        private bool _disposed = false;

        /// <summary>
        /// Returns true if enough time since _LastFiredEvent has passed
        /// </summary>
        private bool EnoughTimeSinceLastEventHasElapsed
        {
            get
            {
                return (DateTime.Now.Ticks - _LastFiredEvent.Ticks) >= (TimeSpan.FromSeconds(_N_SECONDS_TOIGNORE_NEXT_SIGNLEMOUSE_CLICKEVENT).Ticks);
            }
        }

        #endregion

        #region Construction

        /// <summary>
        /// Construct a System Tray Icon (use public properties like ContextMenu,Icon,toolTip to customize further)
        /// </summary>
        /// <param name="ContextMenuInitializer">Callback to initialize the Context Menu (can't be null)</param>
        /// <param name="toolTip">pass in an initial ToolTip to display, defaults to ""</param>
        /// <param name="icon">if null, defaults to systemIcons.Application</param>
        public SysTray(InitializeContextMenu ContextMenuInitializer, string toolTip = "", Icon icon = null)
        {
            if (ContextMenuInitializer == null)
                throw new ArgumentNullException("ContextMenuInitializer can not be Null");
            
            // Imp, in order to initialize the Context Menu Everytime it is needed
            _ContextMenuInitializer = ContextMenuInitializer;

            // Create internal objects
            this.trayNotify = new NotifyIcon();
            this.SingleClickDetectTimer = new TTimerDisp(new ElapsedEventHandler(RealSingleClickDetectTimer_ElapsedEventHandler), _MILISECONDS_FOR_SINGLEMOUSE_CLICKEVENT_TOCOUNT);

            // Add Single / Double-Click Event Handlers
            trayNotify.Click += new EventHandler(trayNotify_Click);
            trayNotify.DoubleClick += new EventHandler(trayNotify_DoubleClick);
            trayNotify.MouseDown += new MouseEventHandler(trayNotify_MouseDown);
            
            // Set ToolTip
            if (!String.IsNullOrEmpty(toolTip))
                this.toolTip = toolTip;
            
            // Set Icon
            if (icon == null)
                this.Icon = new Icon(SystemIcons.Application, 40, 40);
            else
                this.Icon = icon;
        }

        /// <summary>
        /// Finalizer
        /// </summary>
        ~SysTray()
        {
            Dispose(true);
        }

        #endregion

        #region Click Event Handlers

        /// <summary>
        /// Called by NotifyIcon DoubleClick Event, We filter for only the left mouse double-click,
        /// event and fire event when neccessary
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void trayNotify_DoubleClick(object sender, EventArgs e)
        {
            MouseEventArgs args = (MouseEventArgs)e;
            if (args.Button == MouseButtons.Left)
            {
                SingleClickDetectTimer.Stop();
                if (LeftMouseDoubleClick != null && EnoughTimeSinceLastEventHasElapsed)
                {
                    _LastFiredEvent = new TimeSpan(DateTime.Now.Ticks);
                    LeftMouseDoubleClick(new MouseEventArgs(MouseButtons.Left, 2, 0, 0, 0));
                }
            }
        }

        /// <summary>
        // Called by NotifyIcon Click Event, We filter for only the left mouse click,
        /// event and fire event when neccessary
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void trayNotify_Click(object sender, EventArgs e)
        {
            MouseEventArgs args = (MouseEventArgs) e;
            if (args.Button == MouseButtons.Left && EnoughTimeSinceLastEventHasElapsed)
                SingleClickDetectTimer.Start(); // Start Single Click Detect Timer              
        }

        /// <summary>
        /// In order to accurately re-do a context menu, we handle MouseDown for the 
        /// Right-Mouse click. Mouse Down comes in before the click event, which gives
        /// the caller an opportunity to handle/recreate the context menu dynamically, if needed
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        void trayNotify_MouseDown(object sender, MouseEventArgs e)
        {
            MouseEventArgs args = (MouseEventArgs)e;
            if (args.Button == MouseButtons.Right)
            {
                // Dynamically re-create Menu on every Right-Click
                InitializeContextMenuFromScratchUsingInitializer();
            }
        }

        /// <summary>
        /// Used to detect ONLY Single Clicks, since a single-click and then a double-click fires,
        /// we want to ignore the first click,and first see if a double-click comes in, if so, ignore
        /// the single click, otherwise send it. (this is done by trayNotify_Click & transNotify_DoubleClick)
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void RealSingleClickDetectTimer_ElapsedEventHandler(object sender, ElapsedEventArgs e)
        {
            SingleClickDetectTimer.Stop();
            if (LeftMouseClick != null)
            {
                _LastFiredEvent = new TimeSpan(DateTime.Now.Ticks);
                LeftMouseClick(new MouseEventArgs(MouseButtons.Left, 1, 0, 0, 0));
            }
        }

        #endregion

        #region Private Helpers

        /// <summary>
        /// (Re)Initialize Context Menu from scratch, allows us to build different menu's
        /// depending on the application state * External Caller responsible for passing in
        /// the context Menu and Click Event Handler *
        /// </summary>
        private void InitializeContextMenuFromScratchUsingInitializer()
        {
            if (_ContextMenuInitializer != null)
            {
                ContextMenuStrip menuStrip = null;
                EventHandler clickHandler = null;

                // Call Outside Caller's Initialize Context menu Function
                _ContextMenuInitializer(out menuStrip, out clickHandler);

                // Set up the Click Event
                if (menuStrip != null && clickHandler != null)
                    AssignClickEventHandlerToAllMenuItems(menuStrip, clickHandler);

                // Assign New Context Menu
                trayMenuStrip = menuStrip;
            }
        }

        /// <summary>
        /// Calls AssignClickEventHandlerToMenuItem() for each Root Menu Item
        /// </summary>
        /// <param name="menuStrip"></param>
        /// <param name="clickHandler"></param>
        private void AssignClickEventHandlerToAllMenuItems(ContextMenuStrip menuStrip, EventHandler clickHandler)
        {
            if (menuStrip != null)
            {
                foreach (ToolStripMenuItem item in menuStrip.Items.OfType<ToolStripMenuItem>())
                         AssignClickEventHandlerToMenuItem(item, clickHandler);
            }
        }

        /// <summary>
        /// Recursive Function, in order to assign all MenuItems as well as
        /// all subsequent MenuItems, in the DropDownList, the ToolStripMI_Click
        /// event Handler
        /// </summary>
        /// <param name="item">pass in a ToolStripMenuItem to asign the click handler to</param>
        /// <param name="clickHandler"></param>
        private void AssignClickEventHandlerToMenuItem(ToolStripMenuItem item, EventHandler clickHandler)
        {
            if (item.DropDownItems == null || item.DropDownItems.Count == 0)
            {
                if(clickHandler != null)
                   item.Click += clickHandler;
                return;
            }
            else
            {
                foreach (ToolStripMenuItem _item in item.DropDownItems.OfType<ToolStripMenuItem>())
                         AssignClickEventHandlerToMenuItem(_item, clickHandler);
            }
        }

        #endregion

        #region Show N' Hide

        /// <summary>
        /// Show the System Tray Icon
        /// </summary>
        public void Show()
        {
            // Create Context Menu
            InitializeContextMenuFromScratchUsingInitializer();
            trayNotify.Visible = true;
        }

        /// <summary>
        /// Hide the System Tray Icon
        /// </summary>
        public void Hide()
        {
            trayNotify.Visible = false;
        }

        #endregion

        #region Public ShowBallon

        /// <summary>
        /// Type of Icon to show over Ballon
        /// </summary>
        public enum BallonIcon
        {
            None,
            Error,
            Warning,
            Info
        }

        /// <summary>
        /// Pops up a Ballon over the System Tray Icon
        /// </summary>
        /// <param name="BallonTipTitle">Title to show on the Ballon Tip</param>
        /// <param name="BallonTipText">Text to show on the Ballon Tip</param>
        /// <param name="tipIcon">Icon to show on the Ballon tip</param>
        /// <param name="nTimeoutInSeconds">Specify the Timeout in Seconds (System mininimum is 10 seconds)</param>
        public void ShowBallon(string BallonTipTitle, string BallonTipText, BallonIcon tipIcon = BallonIcon.None, int nTimeoutInSeconds = 10)
        {
            ToolTipIcon _tipIcon = ToolTipIcon.None;
            switch (tipIcon)
            {
                case BallonIcon.Error:
                    _tipIcon = ToolTipIcon.Error;
                    break;
                case BallonIcon.Info:
                    _tipIcon = ToolTipIcon.Info;
                    break;
                case BallonIcon.Warning:
                    _tipIcon = ToolTipIcon.Warning;
                    break;
            }
            trayNotify.ShowBalloonTip((int)TimeSpan.FromSeconds(nTimeoutInSeconds).TotalMilliseconds, BallonTipTitle, BallonTipText, _tipIcon);
        }      

        #endregion

        #region IDisposable Members

        /// <summary>
        /// Dispose the Registry Handle
        /// </summary>
        public void Dispose()
        {
            Dispose(true);

            // Use SupressFinalize in case a subclass
            // of this type implements a finalizer
            GC.SuppressFinalize(this);
        }

        /// <summary>
        /// Dispose the Registry Handle
        /// </summary>
        /// <param name="disposing">true, if called from within</param>
        protected virtual void Dispose(bool disposing)
        {
            if (!_disposed)
            {
                if (disposing)
                {
                    if (trayNotify != null)
                        trayNotify.Dispose();
                }

                // Indicate that the instance has been disposed.
                trayNotify = null;
                _disposed = true;
            }
        }

        #endregion
    }
}