using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Nona;

namespace Foundations
{
    public class GuiExceptionHandler : IExceptionHandler
    {
        public static string RenderCrashMessage =
            "The render thread has crashed.  The simulation is unaffected by this and should still be running in " +
            "the background.  However, the graphics won't update anymore until you manually re-enable the render " +
            "thread";

        public static string SimulationCrashMessage =
            "The simulation thread has crashed, and is therefore currently paused.  If you continue, the " +
            "simulation will remain in a paused state until you unpause it.";

        public static string DrawSceneCrashMessage =
            "The DrawScene callback has chrashed, and has therefore been paused.  The simulation is unaffected by " +
            "this and should still be running in the background.  However, the graphics won't update anymore until " +
            "you manually re-enable the draw scene callback.";

        public static string UiCrashMessage =
            "The UI pump thread has crashed.  We can attempt to continue, though.  The simulation thread should be " +
            "unaffected.";

        public static string UnknownCrashMessage =
            "Unhandled exception on unknown thread.  This is (probably) not recoverable.";

        private static bool CreateExceptionDialog(Exception exc, string furtherInformation, bool startNewMessagePump)
        {
            var excDialog = new Lima.ExceptionDialog();
            excDialog.FurtherInformation = furtherInformation;
            excDialog.Exception = exc;
            excDialog.Icon = Properties.Resources.bug;

            Lima.ExceptionDialog.RunExceptionDialog(excDialog, startNewMessagePump);
            return true;
        }

        private static ProtectedLoop.TryHandleExceptionDelegate CreateExceptionHandler(
            string furtherInformation, bool startNewMessagePump = true)
        {
            return exception =>
            {
                CreateExceptionDialog(exception, furtherInformation, startNewMessagePump);
                return true;
            };
        }

        public void ThreadExceptionHandler(object sender, System.Threading.ThreadExceptionEventArgs exception)
        {
            CreateExceptionDialog(exception.Exception, UiCrashMessage, startNewMessagePump: false);
        }

        public void UnknownExceptionHandler(object sender, UnhandledExceptionEventArgs exception)
        {
            // Non UI bug in some other thread.
            System.Windows.Forms.MessageBox.Show(UnknownCrashMessage + "Details: " +
                Environment.NewLine + exception.ExceptionObject.ToString(),
                "Unknown error on unknown thread.");
        }

        public bool SimulationExceptionHandler(Exception exception)
        {
            return CreateExceptionDialog(exception, SimulationCrashMessage, startNewMessagePump: true);
        }

        public bool RenderExceptionHandler(Exception exception)
        {
            return CreateExceptionDialog(exception, RenderCrashMessage, startNewMessagePump: true);
        }

        public bool DrawExceptionHandler(Exception exception)
        {
            return CreateExceptionDialog(exception, DrawSceneCrashMessage, startNewMessagePump: false);
        }
    }
}