/******************************************************************************
 * Spine Runtimes License Agreement
 * Last updated April 5, 2025. Replaces all prior versions.
 *
 * Copyright (c) 2013-2025, Esoteric Software LLC
 *
 * Integration of the Spine Runtimes into software or otherwise creating
 * derivative works of the Spine Runtimes is permitted under the terms and
 * conditions of Section 2 of the Spine Editor License Agreement:
 * http://esotericsoftware.com/spine-editor-license
 *
 * Otherwise, it is permitted to integrate the Spine Runtimes into software
 * or otherwise create derivative works of the Spine Runtimes (collectively,
 * "Products"), provided that each user of the Products must obtain their own
 * Spine Editor license and redistribution of the Products in any form must
 * include this license and copyright notice.
 *
 * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "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 LLC 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
 * THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

//#define CHANGE_BOUNDS_ON_ANIMATION_CHANGE

using UnityEditor;
using UnityEditor.UIElements;
using UnityEngine;
using UnityEngine.UIElements;

namespace Spine.Unity.Editor {

	[CustomPropertyDrawer(typeof(BoundsFromAnimationAttribute))]
	public class BoundsFromAnimationAttributeDrawer : PropertyDrawer {

		protected BoundsFromAnimationAttribute TargetAttribute { get { return (BoundsFromAnimationAttribute)attribute; } }

		public override VisualElement CreatePropertyGUI (SerializedProperty boundsProperty) {
			var container = new VisualElement();
			PropertyField referenceMeshBounds = new PropertyField();
			referenceMeshBounds.BindProperty(boundsProperty);

			var parentPropertyPath = boundsProperty.propertyPath.Substring(0, boundsProperty.propertyPath.LastIndexOf('.'));
			var parent = boundsProperty.serializedObject.FindProperty(parentPropertyPath);
			SerializedProperty animationProperty = parent.FindPropertyRelative(TargetAttribute.animationField);
			SerializedProperty skeletonDataProperty = parent.FindPropertyRelative(TargetAttribute.dataField);
			SerializedProperty skinProperty = parent.FindPropertyRelative(TargetAttribute.skinField);

#if !CHANGE_BOUNDS_ON_ANIMATION_CHANGE
			Button updateBoundsButton = new Button(() => {
				UpdateMeshBounds(boundsProperty, animationProperty.stringValue,
					(SkeletonDataAsset)skeletonDataProperty.objectReferenceValue, skinProperty.stringValue);
			});
			updateBoundsButton.text = "Update Bounds";
			container.Add(updateBoundsButton);
#else
			referenceMeshBounds.TrackPropertyValue(animationProperty, prop => {
				UpdateMeshBounds(boundsProperty, animationProperty.stringValue,
					(SkeletonDataAsset)skeletonDataProperty.objectReferenceValue, skinProperty.stringValue);
			});
#endif
			container.Add(referenceMeshBounds);

			container.Bind(boundsProperty.serializedObject);
			return container;
		}

		protected void UpdateMeshBounds (SerializedProperty boundsProperty, string boundsAnimation,
			SkeletonDataAsset skeletonDataAsset, string skin) {
			if (!skeletonDataAsset)
				return;

			Bounds bounds = CalculateMeshBounds(boundsAnimation, skeletonDataAsset, skin);
			if (bounds.extents.x == 0 || bounds.extents.y == 0) {
				Debug.LogWarning("Please select different Initial Skin and Bounds Animation. Not setting reference " +
					"bounds as current combination (likely no attachments visible) leads to zero Mesh bounds.");
				bounds.center = Vector3.zero;
				bounds.extents = Vector3.one * 2f;
			}
			boundsProperty.boundsValue = bounds;
			boundsProperty.serializedObject.ApplyModifiedProperties();
		}

		protected Bounds CalculateMeshBounds (string animationName, SkeletonDataAsset skeletonDataAsset, string skin) {
			SkeletonData skeletonData = skeletonDataAsset.GetSkeletonData(false);
			Skeleton skeleton = new Skeleton(skeletonData);
			if (!string.IsNullOrEmpty(skin) && !string.Equals(skin, "default", System.StringComparison.Ordinal))
				skeleton.SetSkin(skin);
			skeleton.SetSlotsToSetupPose();

			Spine.Animation animation = skeletonData.FindAnimation(animationName);
			if (animation != null)
				animation.Apply(skeleton, -1, 0, false, null, 1.0f, MixBlend.First, MixDirection.In);

			skeleton.Update(0f);
			skeleton.UpdateWorldTransform(Skeleton.Physics.Update);

			float x, y, width, height;
			SkeletonClipping clipper = new SkeletonClipping();
			float[] vertexBuffer = null;
			skeleton.GetBounds(out x, out y, out width, out height, ref vertexBuffer, clipper);
			if (x == int.MaxValue) {
				return new Bounds();
			}

			Bounds bounds = new Bounds();
			Vector2 halfSize = new Vector2(width * 0.5f, height * 0.5f);
			bounds.center = new Vector3(x + halfSize.x, -y - halfSize.y, 0.0f);
			bounds.extents = new Vector3(halfSize.x, halfSize.y, 0.0f);
			return bounds;
		}
	}
}