/*
*

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package railo.runtime.img.filter;import java.awt.image.BufferedImage;

import railo.runtime.engine.ThreadLocalPageContext;
import railo.runtime.exp.FunctionException;
import railo.runtime.exp.PageException;
import railo.runtime.img.ImageUtil;
import railo.runtime.type.KeyImpl;
import railo.runtime.type.Struct;
import railo.runtime.type.util.CollectionUtil;

/**
 * A filter which adds Gaussian blur to an image, producing a glowing effect.
 *
 */
public class GlowFilter extends GaussianFilter  implements DynFiltering {

	private float amount = 0.5f;
	
	public GlowFilter() {
		radius = 2;
	}
	
	/**
	 * Set the amount of glow.
	 * @param amount the amount
     * @min-value 0
     * @max-value 1
     * @see #getAmount
	 */
	public void setAmount( float amount ) {
		this.amount = amount;
	}
	
	/**
	 * Get the amount of glow.
	 * @return the amount
     * @see #setAmount
	 */
	public float getAmount() {
		return amount;
	}
	
    public BufferedImage filter( BufferedImage src, BufferedImage dst ) {
        int width = src.getWidth();
        int height = src.getHeight();

        if ( dst == null )
            dst = createCompatibleDestImage( src, null );

        int[] inPixels = new int[width*height];
        int[] outPixels = new int[width*height];
        src.getRGB( 0, 0, width, height, inPixels, 0, width );

		if ( radius > 0 ) {
			convolveAndTranspose(kernel, inPixels, outPixels, width, height, alpha, alpha && premultiplyAlpha, false, CLAMP_EDGES);
			convolveAndTranspose(kernel, outPixels, inPixels, height, width, alpha, false, alpha && premultiplyAlpha, CLAMP_EDGES);
		}

        src.getRGB( 0, 0, width, height, outPixels, 0, width );

		float a = 4*amount;

		int index = 0;
		for ( int y = 0; y < height; y++ ) {
			for ( int x = 0; x < width; x++ ) {
				int rgb1 = outPixels[index];
				int r1 = (rgb1 >> 16) & 0xff;
				int g1 = (rgb1 >> 8) & 0xff;
				int b1 = rgb1 & 0xff;

				int rgb2 = inPixels[index];
				int r2 = (rgb2 >> 16) & 0xff;
				int g2 = (rgb2 >> 8) & 0xff;
				int b2 = rgb2 & 0xff;

				r1 = PixelUtils.clamp( (int)(r1 + a * r2) );
				g1 = PixelUtils.clamp( (int)(g1 + a * g2) );
				b1 = PixelUtils.clamp( (int)(b1 + a * b2) );

				inPixels[index] = (rgb1 & 0xff000000) | (r1 << 16) | (g1 << 8) | b1;
				index++;
			}
		}

        dst.setRGB( 0, 0, width, height, inPixels, 0, width );
        return dst;
    }

	public String toString() {
		return "Blur/Glow...";
	}
	public BufferedImage filter(BufferedImage src, Struct parameters) throws PageException {BufferedImage dst=ImageUtil.createBufferedImage(src);
		Object o;
		if((o=parameters.removeEL(KeyImpl.init("Amount")))!=null)setAmount(ImageFilterUtil.toFloatValue(o,"Amount"));
		if((o=parameters.removeEL(KeyImpl.init("Radius")))!=null)setRadius(ImageFilterUtil.toFloatValue(o,"Radius"));
		if((o=parameters.removeEL(KeyImpl.init("EdgeAction")))!=null)setEdgeAction(ImageFilterUtil.toString(o,"EdgeAction"));
		if((o=parameters.removeEL(KeyImpl.init("UseAlpha")))!=null)setUseAlpha(ImageFilterUtil.toBooleanValue(o,"UseAlpha"));
		if((o=parameters.removeEL(KeyImpl.init("PremultiplyAlpha")))!=null)setPremultiplyAlpha(ImageFilterUtil.toBooleanValue(o,"PremultiplyAlpha"));

		// check for arguments not supported
		if(parameters.size()>0) {
			throw new FunctionException(ThreadLocalPageContext.get(), "ImageFilter", 3, "parameters", "the parameter"+(parameters.size()>1?"s":"")+" ["+CollectionUtil.getKeyList(parameters,", ")+"] "+(parameters.size()>1?"are":"is")+" not allowed, only the following parameters are supported [Amount, Radius, Kernel, EdgeAction, UseAlpha, PremultiplyAlpha]");
		}

		return filter(src, dst);
	}
}