// Copyright 1998-2019 Epic Games, Inc. All Rights Reserved.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace EpicCommonUtils
{
	public partial class SlowProgressDialog : Form
	{
		public string ExceptionResult = null;

		public SlowProgressDialog()
		{
			InitializeComponent();
		}

		public delegate void WorkToDoSignature( BackgroundWorker BGWorker, DoWorkEventArgs EventArgs );
		public WorkToDoSignature OnBeginBackgroundWork = null;

		private void SlowWork_RunWorkerCompleted( object sender, RunWorkerCompletedEventArgs e )
		{
			DialogResult = ( ExceptionResult == null ) ? DialogResult.OK : DialogResult.Abort;
		}

		private void SlowWork_DoWork( object sender, DoWorkEventArgs EventArgs )
		{
			try
			{
				OnBeginBackgroundWork( SlowWork, EventArgs );
			}
			catch( Exception ex )
			{
				ExceptionResult = ex.Message;
			}
		}

		private void SlowWork_ProgressChanged( object sender, ProgressChangedEventArgs e )
		{
			ProgressIndicator.Value = Math.Min( Math.Max( ProgressIndicator.Minimum, e.ProgressPercentage ), ProgressIndicator.Maximum );
			StatusLabel.Text = e.UserState as string;
		}

		private void SlowProgressDialog_Shown( object sender, EventArgs e )
		{
			if( OnBeginBackgroundWork != null )
			{
				ExceptionResult = null;
				CancelBtn.Enabled = true;
				SlowWork.RunWorkerAsync();
			}
			else
			{
				DialogResult = DialogResult.Abort;
			}
		}

		private void CancelButton_Click( object sender, EventArgs e )
		{
			CancelBtn.Enabled = false;
			if( OnBeginBackgroundWork != null )
			{
				SlowWork.CancelAsync();
				ExceptionResult = "aborted by user";
				StatusLabel.Text += ", aborting...";
			}
		}
	}
}