/******************************************************************************
 * Spine Runtimes Software License
 * Version 2.3
 * 
 * Copyright (c) 2013-2015, 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 (the "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 otherwise create derivative works, improvements of the
 * Software or develop new applications using the Software 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; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) 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.
 *****************************************************************************/

using System;
using System.Collections.Generic;

namespace Spine {
	/// <summary>Attachment that displays a texture region using a mesh which can be deformed by bones.</summary>
	public class WeightedMeshAttachment : Attachment {
		internal int[] bones;
		internal float[] weights, uvs, regionUVs;
		internal int[] triangles;
		internal float regionOffsetX, regionOffsetY, regionWidth, regionHeight, regionOriginalWidth, regionOriginalHeight;
		internal float r = 1, g = 1, b = 1, a = 1;

		public int HullLength { get; set; }
		public int[] Bones { get { return bones; } set { bones = value; } }
		public float[] Weights { get { return weights; } set { weights = value; } }
		public float[] RegionUVs { get { return regionUVs; } set { regionUVs = value; } }
		public float[] UVs { get { return uvs; } set { uvs = value; } }
		public int[] Triangles { get { return triangles; } set { triangles = value; } }

		public float R { get { return r; } set { r = value; } }
		public float G { get { return g; } set { g = value; } }
		public float B { get { return b; } set { b = value; } }
		public float A { get { return a; } set { a = value; } }

		public String Path { get; set; }
		public Object RendererObject { get; set; }
		public float RegionU { get; set; }
		public float RegionV { get; set; }
		public float RegionU2 { get; set; }
		public float RegionV2 { get; set; }
		public bool RegionRotate { get; set; }
		public float RegionOffsetX { get { return regionOffsetX; } set { regionOffsetX = value; } }
		public float RegionOffsetY { get { return regionOffsetY; } set { regionOffsetY = value; } } // Pixels stripped from the bottom left, unrotated.
		public float RegionWidth { get { return regionWidth; } set { regionWidth = value; } }
		public float RegionHeight { get { return regionHeight; } set { regionHeight = value; } } // Unrotated, stripped size.
		public float RegionOriginalWidth { get { return regionOriginalWidth; } set { regionOriginalWidth = value; } }
		public float RegionOriginalHeight { get { return regionOriginalHeight; } set { regionOriginalHeight = value; } } // Unrotated, unstripped size.

		// Nonessential.
		public int[] Edges { get; set; }
		public float Width { get; set; }
		public float Height { get; set; }

		public WeightedMeshAttachment (string name)
			: base(name) {
		}

		public void UpdateUVs () {
			float u = RegionU, v = RegionV, width = RegionU2 - RegionU, height = RegionV2 - RegionV;
			float[] regionUVs = this.regionUVs;
			if (this.uvs == null || this.uvs.Length != regionUVs.Length) this.uvs = new float[regionUVs.Length];
			float[] uvs = this.uvs;
			if (RegionRotate) {
				for (int i = 0, n = uvs.Length; i < n; i += 2) {
					uvs[i] = u + regionUVs[i + 1] * width;
					uvs[i + 1] = v + height - regionUVs[i] * height;
				}
			} else {
				for (int i = 0, n = uvs.Length; i < n; i += 2) {
					uvs[i] = u + regionUVs[i] * width;
					uvs[i + 1] = v + regionUVs[i + 1] * height;
				}
			}
		}

		public void ComputeWorldVertices (Slot slot, float[] worldVertices) {
			Skeleton skeleton = slot.bone.skeleton;
			ExposedList<Bone> skeletonBones = skeleton.bones;
			float x = skeleton.x, y = skeleton.y;
			float[] weights = this.weights;
			int[] bones = this.bones;
			if (slot.attachmentVerticesCount == 0) {
				for (int w = 0, v = 0, b = 0, n = bones.Length; v < n; w += 2) {
					float wx = 0, wy = 0;
					int nn = bones[v++] + v;
					for (; v < nn; v++, b += 3) {
						Bone bone = skeletonBones.Items[bones[v]];
						float vx = weights[b], vy = weights[b + 1], weight = weights[b + 2];
						wx += (vx * bone.a + vy * bone.b + bone.worldX) * weight;
						wy += (vx * bone.c + vy * bone.d + bone.worldY) * weight;
					}
					worldVertices[w] = wx + x;
					worldVertices[w + 1] = wy + y;
				}
			} else {
				float[] ffd = slot.attachmentVertices;
				for (int w = 0, v = 0, b = 0, f = 0, n = bones.Length; v < n; w += 2) {
					float wx = 0, wy = 0;
					int nn = bones[v++] + v;
					for (; v < nn; v++, b += 3, f += 2) {
						Bone bone = skeletonBones.Items[bones[v]];
						float vx = weights[b] + ffd[f], vy = weights[b + 1] + ffd[f + 1], weight = weights[b + 2];
						wx += (vx * bone.a + vy * bone.b + bone.worldX) * weight;
						wy += (vx * bone.c + vy * bone.d + bone.worldY) * weight;
					}
					worldVertices[w] = wx + x;
					worldVertices[w + 1] = wy + y;
				}
			}
		}
	}
}
