using System;

using System.Diagnostics;

using System.Windows;

using System.Windows.Threading;

using GammaJul.LgLcd.Wpf;



namespace GammaJul.LgLcd.Samples.Wpf {



	/// <summary>

	/// Application class.

	/// </summary>

	internal class App : Application {

		private LcdApplet _applet;

		private DispatcherTimer _timer;

		private SampleControl _sampleControl;

		private LcdDeviceQvga _qvgaDevice;



		private delegate void Action();



		/// <summary>

		/// On startup, we are creation a new Applet.

		/// </summary>

		/// <param name="e"></param>

		protected override void OnStartup(StartupEventArgs e) {

			base.OnStartup(e);

			_applet = new LcdApplet("GammaJul LgLcd WPF Sample", LcdAppletCapabilities.Qvga);

			

			// Register to events to know when a device arrives, then connects the applet to the LCD Manager

			_applet.DeviceArrival += Applet_DeviceArrival;

			_applet.Connect();

		}



		/// <summary>

		/// Simple utility method to always executes a method on the Application's thread.

		/// </summary>

		/// <param name="action">Method to execute.</param>

		private void Invoke(Action action) {

			if (CheckAccess())

				action();

			else

				Dispatcher.BeginInvoke(action, DispatcherPriority.Render);

		}



		/// <summary>

		/// This event handler will be called whenever a new device of a given type arrives in the system.

		/// This is where you should opens the device you want to shows the applet on.

		/// Take special care for thread-safety as the SDK calls this handler in another thread.

		/// </summary>

		private void Applet_DeviceArrival(object sender, LcdDeviceTypeEventArgs e) {

			// since with specified LcdAppletCapabilities.Qvga at the Applet's creation,

			// we will only receive QVGA arrival notifications.

			Debug.Assert(e.DeviceType == LcdDeviceType.Qvga);

			Invoke(OnQvgaDeviceArrived);

		}



		private void OnQvgaDeviceArrived() {



			// First device arrival, creates the device

			if (_qvgaDevice == null) {

				_qvgaDevice = (LcdDeviceQvga) _applet.OpenDeviceByType(LcdDeviceType.Qvga);

				_sampleControl = new SampleControl();

				_qvgaDevice.CurrentPage = new LcdWpfPage(_qvgaDevice) {

					Element = _sampleControl

				};

				_qvgaDevice.SoftButtonsChanged += QvgaDevice_SoftButtonsChanged;



				// Starts a timer to update the screen

				_timer = new DispatcherTimer(TimeSpan.FromMilliseconds(5.0), DispatcherPriority.Render, Timer_Tick, Dispatcher.CurrentDispatcher);

			}



			// Subsequent device arrival means the device was removed and replugged, simply reopens it

			else

				_qvgaDevice.ReOpen();

			_qvgaDevice.DoUpdateAndDraw();

		}



		/// <summary>

		/// Updates the LCD screen.

		/// </summary>

		private void Timer_Tick(object sender, EventArgs e) {

			if (_applet.IsEnabled && _qvgaDevice != null && !_qvgaDevice.IsDisposed)

				_qvgaDevice.DoUpdateAndDraw();

		}



		/// <summary>

		/// When soft buttons are pressed, switch to previous image if left arrow button was clicked,

		/// switch to next if the right arrow button was clicked, or closes the application if

		/// the cancel button was clicked.

		/// </summary>

		private void QvgaDevice_SoftButtonsChanged(object sender, LcdSoftButtonsEventArgs e) {

			if ((e.SoftButtons & LcdSoftButtons.Cancel) == LcdSoftButtons.Cancel)

				Invoke(Shutdown);

			else if ((e.SoftButtons & LcdSoftButtons.Left) == LcdSoftButtons.Left)

				Invoke(_sampleControl.PreviousImage);

			else if ((e.SoftButtons & LcdSoftButtons.Right) == LcdSoftButtons.Right)

				Invoke(_sampleControl.NextImage);

		}



		[STAThread]

		internal static void Main() {

			App app = new App();

			app.Run();

		}

	}



}