/******************************************************************************
 * Spine Runtimes Software License v2.5
 *
 * Copyright (c) 2013-2016, Esoteric Software
 * All rights reserved.
 *
 * You are granted a perpetual, non-exclusive, non-sublicensable, and
 * non-transferable license to use, install, execute, and perform the Spine
 * Runtimes software and derivative works solely for personal or internal
 * use. Without the written permission of Esoteric Software (see Section 2 of
 * the Spine Software License Agreement), you may not (a) modify, translate,
 * adapt, or develop new applications using the Spine Runtimes or otherwise
 * create derivative works or improvements of the Spine Runtimes or (b) remove,
 * delete, alter, or obscure any trademarks or any copyright, trademark, patent,
 * or other intellectual property or proprietary rights notices on or in the
 * Software, including any copy thereof. Redistributions in binary or source
 * form must include this license and terms.
 *
 * THIS SOFTWARE IS PROVIDED BY ESOTERIC SOFTWARE "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL ESOTERIC SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, BUSINESS INTERRUPTION, OR LOSS OF
 * USE, DATA, OR PROFITS) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

// Contributed by: Lost Polygon

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using UnityEditor;
using UnityEngine;
using Spine.Unity.Modules;

namespace Spine.Unity.Editor {

	// This script is not intended for use with code. See the readme.txt file in SkeletonRendererCustomMaterials folder to learn more.
	[CustomEditor(typeof(SkeletonRendererCustomMaterials))]
	public class SkeletonRendererCustomMaterialsInspector : UnityEditor.Editor {
		List<SkeletonRendererCustomMaterials.AtlasMaterialOverride> componentCustomMaterialOverrides, _customMaterialOverridesPrev;
		List<SkeletonRendererCustomMaterials.SlotMaterialOverride> componentCustomSlotMaterials, _customSlotMaterialsPrev;
		SkeletonRendererCustomMaterials component;

		const BindingFlags PrivateInstance = BindingFlags.Instance | BindingFlags.NonPublic;
		MethodInfo RemoveCustomMaterialOverrides, RemoveCustomSlotMaterials, SetCustomMaterialOverrides, SetCustomSlotMaterials;

		#region SkeletonRenderer context menu
		[MenuItem("CONTEXT/SkeletonRenderer/Add Basic Serialized Custom Materials")]
		static void AddSkeletonRendererCustomMaterials (MenuCommand menuCommand) {
			var skeletonRenderer = (SkeletonRenderer)menuCommand.context;
			var newComponent = skeletonRenderer.gameObject.AddComponent<SkeletonRendererCustomMaterials>();
			Undo.RegisterCreatedObjectUndo(newComponent, "Add Basic Serialized Custom Materials");
		}

		[MenuItem("CONTEXT/SkeletonRenderer/Add Basic Serialized Custom Materials", true)]
		static bool AddSkeletonRendererCustomMaterials_Validate (MenuCommand menuCommand) {
			var skeletonRenderer = (SkeletonRenderer)menuCommand.context;
			return (skeletonRenderer.GetComponent<SkeletonRendererCustomMaterials>() == null);
		}
		#endregion

		void OnEnable () {
			Type cm = typeof(SkeletonRendererCustomMaterials);
			RemoveCustomMaterialOverrides = cm.GetMethod("RemoveCustomMaterialOverrides", PrivateInstance);
			RemoveCustomSlotMaterials = cm.GetMethod("RemoveCustomSlotMaterials", PrivateInstance);
			SetCustomMaterialOverrides = cm.GetMethod("SetCustomMaterialOverrides", PrivateInstance);
			SetCustomSlotMaterials = cm.GetMethod("SetCustomSlotMaterials", PrivateInstance);
		}

		public override void OnInspectorGUI () {
			component = (SkeletonRendererCustomMaterials)target;
			var skeletonRenderer = component.skeletonRenderer;

			// Draw the default inspector
			DrawDefaultInspector();

			if (serializedObject.isEditingMultipleObjects)
				return;

			if (componentCustomMaterialOverrides == null) {
				Type cm = typeof(SkeletonRendererCustomMaterials);
				componentCustomMaterialOverrides = cm.GetField("customMaterialOverrides", PrivateInstance).GetValue(component) as List<SkeletonRendererCustomMaterials.AtlasMaterialOverride>;
				componentCustomSlotMaterials = cm.GetField("customSlotMaterials", PrivateInstance).GetValue(component) as List<SkeletonRendererCustomMaterials.SlotMaterialOverride>;
				if (componentCustomMaterialOverrides == null) {
					Debug.Log("Reflection failed.");
					return;
				}
			}

			// Fill with current values at start
			if (_customMaterialOverridesPrev == null || _customSlotMaterialsPrev == null) {
				_customMaterialOverridesPrev = CopyList(componentCustomMaterialOverrides);
				_customSlotMaterialsPrev = CopyList(componentCustomSlotMaterials);
			}

			// Compare new values with saved. If change is detected: 
			// store new values, restore old values, remove overrides, restore new values, restore overrides.

			// 1. Store new values
			var customMaterialOverridesNew = CopyList(componentCustomMaterialOverrides);
			var customSlotMaterialsNew = CopyList(componentCustomSlotMaterials);
			
			// Detect changes
			if (!_customMaterialOverridesPrev.SequenceEqual(customMaterialOverridesNew) ||
				!_customSlotMaterialsPrev.SequenceEqual(customSlotMaterialsNew)) {
				// 2. Restore old values
				componentCustomMaterialOverrides.Clear();
				componentCustomSlotMaterials.Clear();
				componentCustomMaterialOverrides.AddRange(_customMaterialOverridesPrev);
				componentCustomSlotMaterials.AddRange(_customSlotMaterialsPrev);

				// 3. Remove overrides
				RemoveCustomMaterials();

				// 4. Restore new values
				componentCustomMaterialOverrides.Clear();
				componentCustomSlotMaterials.Clear();
				componentCustomMaterialOverrides.AddRange(customMaterialOverridesNew);
				componentCustomSlotMaterials.AddRange(customSlotMaterialsNew);

				// 5. Restore overrides
				SetCustomMaterials();

				if (skeletonRenderer != null)
					skeletonRenderer.LateUpdate();
			}

			_customMaterialOverridesPrev = CopyList(componentCustomMaterialOverrides);
			_customSlotMaterialsPrev = CopyList(componentCustomSlotMaterials);

			if (SpineInspectorUtility.LargeCenteredButton(new GUIContent("Clear and Reapply Changes", "Removes all non-serialized overrides in the SkeletonRenderer and reapplies the overrides on this component."))) {
				if (skeletonRenderer != null) {
					skeletonRenderer.CustomMaterialOverride.Clear();
					skeletonRenderer.CustomSlotMaterials.Clear();
					RemoveCustomMaterials();
					SetCustomMaterials();
					skeletonRenderer.LateUpdate();
				}
			}
		}

		void RemoveCustomMaterials () {
			RemoveCustomMaterialOverrides.Invoke(component, null);
			RemoveCustomSlotMaterials.Invoke(component, null);
		}

		void SetCustomMaterials () {
			SetCustomMaterialOverrides.Invoke(component, null);
			SetCustomSlotMaterials.Invoke(component, null);
		}

		static List<T> CopyList<T> (List<T> list) {
			return list.GetRange(0, list.Count);
		} 
	}
}
