Assets.java

package com.bluebananagames.gametemplate;

import java.util.HashMap;
import java.util.List;

import com.badlogic.gdx.assets.AssetManager;
import com.badlogic.gdx.audio.Music;
import com.badlogic.gdx.audio.Sound;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.Texture.TextureFilter;
import com.badlogic.gdx.graphics.g2d.BitmapFont;
import com.badlogic.gdx.graphics.g2d.Sprite;
import com.badlogic.gdx.graphics.g2d.TextureRegion;

public class Assets {

	// TODO: maybe add support for asynchronous loading of assets

	private static final String IMAGES_PATH = "data/images/";
	private static final String FONTS_PATH = "data/fonts/";
	private static final String SFX_PATH = "data/sfx/";
	private static final String MUSIC_PATH = "data/music/";

	private AssetManager assetManager = new AssetManager();
	private HashMap<String, Object> assets = new HashMap<String, Object>();

	/**
	 * Retrieves an asset from the asset map. Before it can be retrieved, it has
	 * to be loaded with the corresponding preload method.
	 * 
	 * @param filename
	 *            The name of the asset file relative to its asset type folder
	 *            path.
	 * @return
	 */
	public Object getAsset(String filename) {
		Object asset = assets.get(filename);
		if (asset == null) {
			warnNotLoaded(filename);
		}
		return asset;
	}

	public void unloadAssets(List<String> filenames) {
		for (String filename : filenames) {
			Object asset = assets.get(filename);
			if (asset != null) {
				assets.remove(filename);

				String assetPath = null;
				if (asset.getClass() == Sprite.class) {
					assetPath = imageFilePath(filename);
				} else if (asset.getClass() == BitmapFont.class) {
					assetPath = fontFilePath(filename);
				} else if (asset.getClass() == Sound.class) {
					assetPath = sfxFilePath(filename);
				} else if (asset.getClass() == Music.class) {
					assetPath = musicFilePath(filename);
				}

				if (assetPath != null) {
					assetManager.unload(assetPath);
				}
			}
		}
	}

	public void preloadSprites(List<String> filenames) {
		for (String filename : filenames) {
			assetManager.load(imageFilePath(filename), Texture.class);
		}
		assetManager.finishLoading();

		for (String filename : filenames) {
			assets.put(filename, loadSprite(filename));
		}
	}

	public Sprite getSprite(String filename) {
		return (Sprite) getAsset(filename);
	}

	public void preloadSFXs(List<String> filenames) {
		for (String filename : filenames) {
			assetManager.load(sfxFilePath(filename), Sound.class);
		}
		assetManager.finishLoading();

		for (String filename : filenames) {
			assets.put(filename, loadSound(filename));
		}
	}

	public Sound getSound(String filename) {
		return (Sound) getAsset(filename);
	}

	public void preloadMusic(List<String> filenames) {
		for (String filename : filenames) {
			assetManager.load(musicFilePath(filename), Music.class);
		}
		assetManager.finishLoading();

		for (String filename : filenames) {
			assets.put(filename, loadMusic(filename));
		}
	}

	public Music getMusic(String filename) {
		return (Music) getAsset(filename);
	}

	/**
	 * Loads fonts for later use.
	 * 
	 * @param filenames
	 *            A list of font names. Each font has to have a .fnt and a .png
	 *            file which are existing in the FONTS_PATH directory. Pass the
	 *            fonts' names with .fnt extension. E.g. "comicsans.fnt".
	 */
	public void preloadFonts(List<String> filenames) {
		for (String filename : filenames) {
			assetManager.load(fontFilePath(filename), BitmapFont.class);
		}
		assetManager.finishLoading();

		for (String filename : filenames) {
			assets.put(filename, loadFont(filename));
		}
	}

	public BitmapFont getFont(String fontname) {
		return (BitmapFont) getAsset(fontname);
	}

	public void dispose() {
		// TODO: dispose asset instances??
		assetManager.dispose();
	}

	// HELPERS

	private Sprite loadSprite(String filename) {
		Sprite sprite = (Sprite) assets.get(filename);
		if (sprite != null) {
			return sprite;
		}

		Texture texture = assetManager.get(imageFilePath(filename),
				Texture.class);
		texture.setFilter(TextureFilter.Linear, TextureFilter.Linear);
		TextureRegion region = new TextureRegion(texture, 0, 0,
				texture.getWidth(), texture.getHeight());
		sprite = new Sprite(region);
		sprite.setOrigin(sprite.getWidth() / 2, sprite.getHeight() / 2);
		sprite.setPosition(0, 0);

		return sprite;
	}

	private BitmapFont loadFont(String fontname) {
		return assetManager.get(fontFilePath(fontname), BitmapFont.class);
	}

	private Sound loadSound(String filename) {
		return assetManager.get(sfxFilePath(filename), Sound.class);
	}

	private Music loadMusic(String filename) {
		return assetManager.get(musicFilePath(filename), Music.class);
	}

	private void warnNotLoaded(String filename) {
		System.out.println("ASSETS WARNING: " + filename + " is not loaded!");
	}

	private static String imageFilePath(String filename) {
		return IMAGES_PATH + filename;
	}

	private static String fontFilePath(String filename) {
		return FONTS_PATH + filename;
	}

	private static String sfxFilePath(String filename) {
		return SFX_PATH + filename;
	}

	private static String musicFilePath(String filename) {
		return MUSIC_PATH + filename;
	}

}