/******************************************************************************
 * 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.IO;
using UnityEngine;
using Spine;

namespace Spine.Unity {
	/// <summary>Loads and stores a Spine atlas and list of materials.</summary>
	public class AtlasAsset : ScriptableObject {
		public TextAsset atlasFile;
		public Material[] materials;
		private Atlas atlas;

		public void Reset () {
			atlas = null;
		}

		/// <returns>The atlas or null if it could not be loaded.</returns>
		public Atlas GetAtlas () {
			if (atlasFile == null) {
				Debug.LogError("Atlas file not set for atlas asset: " + name, this);
				Reset();
				return null;
			}

			if (materials == null || materials.Length == 0) {
				Debug.LogError("Materials not set for atlas asset: " + name, this);
				Reset();
				return null;
			}

			if (atlas != null)
				return atlas;

			try {
				atlas = new Atlas(new StringReader(atlasFile.text), "", new MaterialsTextureLoader(this));
				atlas.FlipV();
				return atlas;
			} catch (Exception ex) {
				Debug.LogError("Error reading atlas file for atlas asset: " + name + "\n" + ex.Message + "\n" + ex.StackTrace, this);
				return null;
			}
		}

		public Sprite GenerateSprite (string name, out Material material) {
			AtlasRegion region = atlas.FindRegion(name);

			Sprite sprite = null;
			material = null;

			if (region != null) {
				//sprite.rect
			}

			return sprite;
		}

		public Mesh GenerateMesh (string name, Mesh mesh, out Material material, float scale = 0.01f) {
			AtlasRegion region = atlas.FindRegion(name);
			material = null;
			if (region != null) {
				if (mesh == null) {
					mesh = new Mesh();
					mesh.name = name;
				}

				Vector3[] verts = new Vector3[4];
				Vector2[] uvs = new Vector2[4];
				Color[] colors = new Color[4] { Color.white, Color.white, Color.white, Color.white };
				int[] triangles = new int[6] { 0, 1, 2, 2, 3, 0 };

				float left, right, top, bottom;
				left = region.width / -2f;
				right = left * -1f;
				top = region.height / 2f;
				bottom = top * -1;

				verts[0] = new Vector3(left, bottom, 0) * scale;
				verts[1] = new Vector3(left, top, 0) * scale;
				verts[2] = new Vector3(right, top, 0) * scale;
				verts[3] = new Vector3(right, bottom, 0) * scale;
				float u, v, u2, v2;
				u = region.u;
				v = region.v;
				u2 = region.u2;
				v2 = region.v2;

				if (!region.rotate) {
					uvs[0] = new Vector2(u, v2);
					uvs[1] = new Vector2(u, v);
					uvs[2] = new Vector2(u2, v);
					uvs[3] = new Vector2(u2, v2);
				} else {
					uvs[0] = new Vector2(u2, v2);
					uvs[1] = new Vector2(u, v2);
					uvs[2] = new Vector2(u, v);
					uvs[3] = new Vector2(u2, v);
				}

				mesh.triangles = new int[0];
				mesh.vertices = verts;
				mesh.uv = uvs;
				mesh.colors = colors;
				mesh.triangles = triangles;
				mesh.RecalculateNormals();
				mesh.RecalculateBounds();

				material = (Material)region.page.rendererObject;
			} else {
				mesh = null;
			}

			return mesh;
		}
	}

	public class MaterialsTextureLoader : TextureLoader {
		AtlasAsset atlasAsset;

		public MaterialsTextureLoader (AtlasAsset atlasAsset) {
			this.atlasAsset = atlasAsset;
		}

		public void Load (AtlasPage page, String path) {
			String name = Path.GetFileNameWithoutExtension(path);
			Material material = null;
			foreach (Material other in atlasAsset.materials) {
				if (other.mainTexture == null) {
					Debug.LogError("Material is missing texture: " + other.name, other);
					return;
				}
				if (other.mainTexture.name == name) {
					material = other;
					break;
				}
			}
			if (material == null) {
				Debug.LogError("Material with texture name \"" + name + "\" not found for atlas asset: " + atlasAsset.name, atlasAsset);
				return;
			}
			page.rendererObject = material;

			// Very old atlas files expected the texture's actual size to be used at runtime.
			if (page.width == 0 || page.height == 0) {
				page.width = material.mainTexture.width;
				page.height = material.mainTexture.height;
			}
		}

		public void Unload (object texture) {
		}
	}
}
