package mods.betterfoliage.client.resource;

import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import javax.imageio.ImageIO;

import mods.betterfoliage.BetterFoliage;
import net.minecraft.client.Minecraft;
import net.minecraft.client.resources.IResource;
import net.minecraft.client.resources.IResourceManager;
import net.minecraft.client.resources.data.IMetadataSection;
import net.minecraft.util.ResourceLocation;
import cpw.mods.fml.relauncher.Side;
import cpw.mods.fml.relauncher.SideOnly;

/** {@link IResource} containing an autogenerated round crossleaf texture
 * @author octarine-noise
 */
@SideOnly(Side.CLIENT)
public class LeafTextureResource implements IResource {

	/** Raw PNG data*/
	protected byte[] data = null;
	
	/** Name of the default alpha mask to use */
	public static String defaultMask = "rough";
	
	/** Resource to return if generation fails */
	public IResource fallbackResource;
	
	public LeafTextureResource(ResourceLocation resLeaf, IResource fallbackResource) {
		this.fallbackResource = fallbackResource;
		
		IResourceManager resourceManager = Minecraft.getMinecraft().getResourceManager();
		try {
			// load normal leaf texture
			ResourceLocation origResource = new ResourceLocation(resLeaf.getResourceDomain(), "textures/blocks/" + resLeaf.getResourcePath());
			BufferedImage origImage = ImageIO.read(resourceManager.getResource(origResource).getInputStream());
			if (origImage.getWidth() != origImage.getHeight()) return;
			int size = origImage.getWidth();

			// load alpha mask of appropriate size
			BufferedImage maskImage = loadLeafMaskImage(defaultMask, size * 2);
			int scale = size * 2 / maskImage.getWidth();
			
			// tile leaf texture 2x2
			BufferedImage overlayIcon = new BufferedImage(size * 2, size * 2, BufferedImage.TYPE_4BYTE_ABGR);
			Graphics2D graphics = overlayIcon.createGraphics();
			graphics.drawImage(origImage, 0, 0, null);
			graphics.drawImage(origImage, 0, size, null);
			graphics.drawImage(origImage, size, 0, null);
			graphics.drawImage(origImage, size, size, null);
			
			// overlay mask alpha on texture
			for (int x = 0; x < overlayIcon.getWidth(); x++) {
				for (int y = 0; y < overlayIcon.getHeight(); y++) {
					long origPixel = overlayIcon.getRGB(x, y) & 0xFFFFFFFFl;
					long maskPixel = maskImage.getRGB(x / scale, y / scale) & 0xFF000000l | 0x00FFFFFF;
					overlayIcon.setRGB(x, y, (int) (origPixel & maskPixel));
				}
			}

			// create PNG image
			ByteArrayOutputStream baos = new ByteArrayOutputStream();
			ImageIO.write(overlayIcon, "PNG", baos);
			data = baos.toByteArray();
		} catch (Exception e) {
			// stop log spam with GLSL installed
			if (e instanceof FileNotFoundException) return;
			BetterFoliage.log.info(String.format("Could not create leaf texture: %s, exception: %s", resLeaf.toString(), e.getClass().getSimpleName()));
		}
	}
	
	/** Loads the alpha mask of the given type and size. If a mask of the exact size can not be found,
	 *  will try to load progressively smaller masks down to 16x16
	 * @param type mask type
	 * @param size texture size
	 * @return alpha mask
	 */
	protected BufferedImage loadLeafMaskImage(String type, int size) {
		IResourceManager resourceManager = Minecraft.getMinecraft().getResourceManager();
		IResource maskResource = null;
		
		while (maskResource == null && size >= 16) {
			try {
				maskResource = resourceManager.getResource(new ResourceLocation(String.format("betterfoliage:textures/blocks/leafmask_%d_%s.png", size, type)));
			} catch (Exception e) {}
			size /= 2;
		}
		
		try {
			return maskResource == null ? null : ImageIO.read(maskResource.getInputStream());
		} catch (IOException e) {
			return null;
		}
	}
	
	public InputStream getInputStream() {
		return data != null ? new ByteArrayInputStream(data) : fallbackResource.getInputStream();
	}

	public boolean hasMetadata() {
		return false;
	}

	public IMetadataSection getMetadata(String var1) {
		return null;
	}

}