// 
// ShapesHistoryItem.cs
//  
// Author:
//       Andrew Davis <andrew.3.1415@gmail.com>
// 
// Copyright (c) 2013 Andrew Davis, GSoC 2013 & 2014
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

using System;
using Pinta.Core;
using Cairo;

namespace Pinta.Tools
{
	public class ShapesHistoryItem : BaseHistoryItem
	{
        private BaseEditEngine ee;

		private UserLayer userLayer;

		private SurfaceDiff userSurfaceDiff;
		private ImageSurface userSurface;

		private ShapeEngineCollection sEngines;

		private int selectedPointIndex, selectedShapeIndex;

		private bool redrawEverything;

		/// <summary>
		/// A history item for when shapes are finalized.
		/// </summary>
        /// <param name="passedEE">The EditEngine being used.</param>
		/// <param name="icon">The history item's icon.</param>
		/// <param name="text">The history item's title.</param>
		/// <param name="passedUserSurface">The stored UserLayer surface.</param>
		/// <param name="passedUserLayer">The UserLayer being modified.</param>
		/// <param name="passedSelectedPointIndex">The selected point's index.</param>
		/// <param name="passedSelectedShapeIndex">The selected point's shape index.</param>
		/// <param name="passedRedrawEverything">Whether every shape should be redrawn when undoing (e.g. finalization).</param>
        public ShapesHistoryItem(BaseEditEngine passedEE, string icon, string text, ImageSurface passedUserSurface, UserLayer passedUserLayer,
			int passedSelectedPointIndex, int passedSelectedShapeIndex, bool passedRedrawEverything) : base(icon, text)
		{
            ee = passedEE;

			userLayer = passedUserLayer;


			userSurfaceDiff = SurfaceDiff.Create(passedUserSurface, userLayer.Surface, true);

			if (userSurfaceDiff == null)
			{
				userSurface = passedUserSurface;
			}
			else
			{
				(passedUserSurface as IDisposable).Dispose();
			}


			sEngines = BaseEditEngine.SEngines.PartialClone();
			selectedPointIndex = passedSelectedPointIndex;
			selectedShapeIndex = passedSelectedShapeIndex;

			redrawEverything = passedRedrawEverything;
		}

		public override void Undo()
		{
			Swap(redrawEverything);
		}

		public override void Redo()
		{
			Swap(false);
		}

		private void Swap(bool redraw)
		{
			// Grab the original surface
			ImageSurface surf = userLayer.Surface;

			if (userSurfaceDiff != null)
			{
				userSurfaceDiff.ApplyAndSwap(surf);

				PintaCore.Workspace.Invalidate(userSurfaceDiff.GetBounds());
			}
			else
			{
				// Undo to the "old" surface
				userLayer.Surface = userSurface;

				// Store the original surface for Redo
				userSurface = surf;

				//Redraw everything since surfaces were swapped.
				PintaCore.Workspace.Invalidate();
			}

            Swap (ref sEngines, ref BaseEditEngine.SEngines);

			//Ensure that all of the shapes that should no longer be drawn have their ReEditableLayer removed from the drawing loop.
			foreach (ShapeEngine se in sEngines)
			{
				//Determine if it is currently in the drawing loop and should no longer be. Note: a DrawingLayer could be both removed and then
				//later added in the same swap operation, but this is faster than looping through each ShapeEngine in BaseEditEngine.SEngines.
				if (se.DrawingLayer.InTheLoop && !BaseEditEngine.SEngines.Contains(se))
				{
					se.DrawingLayer.TryRemoveLayer();
				}
			}

			//Ensure that all of the shapes that should now be drawn have their ReEditableLayer in the drawing loop.
			foreach (ShapeEngine se in BaseEditEngine.SEngines)
			{
				//Determine if it is currently out of the drawing loop; if not, it should be.
				if (!se.DrawingLayer.InTheLoop)
				{
					se.DrawingLayer.TryAddLayer();
				}
			}

            Swap (ref selectedPointIndex, ref ee.SelectedPointIndex);
            Swap (ref selectedShapeIndex, ref ee.SelectedShapeIndex);

			//Determine if the currently active tool matches the shape's corresponding tool, and if not, switch to it.
			if (BaseEditEngine.ActivateCorrespondingTool(ee.SelectedShapeIndex, true) != null)
			{
				//The currently active tool now matches the shape's corresponding tool.

				if (redraw)
				{
					((ShapeTool)PintaCore.Tools.CurrentTool).EditEngine.DrawAllShapes();
				}
			}
		}

		public override void Dispose()
		{
			// Free up native surface
			if (userSurface != null)
				(userSurface as IDisposable).Dispose();
		}
	}
}
