package com.bladecoder.engine.spine;

import com.badlogic.gdx.assets.AssetDescriptor;
import com.badlogic.gdx.assets.AssetLoaderParameters;
import com.badlogic.gdx.assets.AssetManager;
import com.badlogic.gdx.assets.loaders.AsynchronousAssetLoader;
import com.badlogic.gdx.assets.loaders.FileHandleResolver;
import com.badlogic.gdx.files.FileHandle;
import com.badlogic.gdx.graphics.g2d.TextureAtlas;
import com.badlogic.gdx.utils.Array;
import com.esotericsoftware.spine.SkeletonBinary;
import com.esotericsoftware.spine.SkeletonData;
import com.esotericsoftware.spine.SkeletonJson;

/**
 * {@link AssetLoader} for {@link SkeletonData} instances. Loads an exported
 * Spine's skeleton data. The atlas with the images will be loaded as a
 * dependency. This has to be declared as a {@link SkeletonDataLoaderParameter}
 * in the {@link AssetManager#load(String, Class, AssetLoaderParameters)} call.
 * Supports both binary and JSON skeleton format files. If the animation file
 * name has a 'skel' extension, it will be loaded as binary. Any other extension
 * will be assumed as JSON.
 *
 * Example: suppose you have 'data/spine/character.atlas',
 * 'data/spine/character.png' and 'data/spine/character.skel'. To load it with
 * an asset manager, just do the following: *
 * 
 * <pre>
* {@code
* assetManager.setLoader(SkeletonData.class, new SkeletonDataLoader(new InternalFileHandleResolver()));
* SkeletonDataLoaderParameter parameter = new SkeletonDataLoaderParameter("data/spine/character.atlas");
* assetManager.load("data/spine/character.skel", SkeletonData.class, parameter);
* }
 * </pre>
 * 
 * @author Alvaro Barbeira
 */
public class SkeletonDataLoader
		extends AsynchronousAssetLoader<SkeletonData, SkeletonDataLoader.SkeletonDataLoaderParameter> {

	SkeletonData skeletonData;

	public SkeletonDataLoader(FileHandleResolver resolver) {
		super(resolver);
	}

	@Override
	public void loadAsync(AssetManager manager, String fileName, FileHandle file,
			SkeletonDataLoaderParameter parameter) {
		skeletonData = null;
		TextureAtlas atlas = manager.get(parameter.atlasName, TextureAtlas.class);

		String extension = file.extension();
		if (extension.toLowerCase().equals("skel")) {
			SkeletonBinary skeletonBinary = new SkeletonBinary(atlas);
			skeletonBinary.setScale(parameter.scale);
			skeletonData = skeletonBinary.readSkeletonData(file);
		} else {
			SkeletonJson skeletonJson = new SkeletonJson(atlas);
			skeletonJson.setScale(parameter.scale);
			skeletonData = skeletonJson.readSkeletonData(file);
		}
	}

	@Override
	public SkeletonData loadSync(AssetManager manager, String fileName, FileHandle file,
			SkeletonDataLoaderParameter parameter) {
		return skeletonData;
	}

	@SuppressWarnings({ "rawtypes", "unchecked" })
	@Override
	public Array<AssetDescriptor> getDependencies(String fileName, FileHandle file,
			SkeletonDataLoaderParameter parameter) {
		Array<AssetDescriptor> deps = new Array<AssetDescriptor>();
		deps.add(new AssetDescriptor(parameter.atlasName, TextureAtlas.class));
		return deps;
	}

	/**
	 * Mandatory parameter to be passed to
	 * {@link AssetManager#load(String, Class, AssetLoaderParameters)}. This
	 * will insure the skeleton data is loaded correctly
	 * 
	 * @author Alvaro Barbeira
	 */
	static public class SkeletonDataLoaderParameter extends AssetLoaderParameters<SkeletonData> {
		// A SkeletonJson must be loaded from an atlas.
		public String atlasName;
		public float scale;

		public SkeletonDataLoaderParameter(String atlasName, float scale) {
			this.atlasName = atlasName;
			this.scale = scale;
		}

		public SkeletonDataLoaderParameter(String atlasName) {
			this(atlasName, 1);
		}
	}
}