package util;

import gui.intro.Login_GUI;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.font.FontRenderContext;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.net.URL;

import javax.swing.ImageIcon;

import org.apache.log4j.Logger;

/**
 * Helper class for loading resources.
 * This should be error safe loaders with a fall back in case the
 * requested resource can't be found, or isn't of the expected type.
 */
public class ResourceLoader {

	/**
	 * Logger for this class
	 */
	private final static Logger LOGGER = Logger.getLogger(ResourceLoader.class);
	
	/**
	 * Load the given resource as an ImageIcon.
	 * This is guaranteed to never throw an Exception and always return
	 * an ImageIcon. If the requested resource could not be loaded,
	 * an icon is generated, containing an error message. If even that
	 * fails, an empty icon is returned.
	 * @param path Resource path to load
	 * @param description Icon description
	 * @return ImageIcon instance
	 */
	public static ImageIcon getIcon(String path, String description) {
		URL url = ResourceLoader.class.getResource(path);
		if (url == null) {
			LOGGER.error("Resource not found: " + path);
		} else {
			try {
				return new ImageIcon(url, description);
			} catch (Exception e) {
				LOGGER.error("Resource not loadable: " + path);
			}
		}
		// If we reach here loading failed, create image containing error
		// message
		try {
			return errorIcon("Invalid Resource: " + path);
		} catch (Throwable t) {
			return new ImageIcon();
		}
	}
	
	/**
	 * Load the given resource as an ImageIcon.
	 * This is guaranteed to never throw an Exception and always return
	 * an ImageIcon. If the requested resource could not be loaded,
	 * an icon is generated, containing an error message. If even that
	 * fails, an empty icon is returned.
	 * @param path Resource path to load
	 * @return ImageIcon instance
	 */
	public static ImageIcon getIcon(String path)
	{
		return getIcon(path, path);
	}

	/**
	 * Helper that will create an icon with given text.
	 * @param errorText Text to render to icon
	 * @return the icon
	 */
	private static ImageIcon errorIcon(String errorText) {
		Font font = new Font("Tahoma", Font.PLAIN, 20);

		// get dimensions of text
		FontRenderContext frc = new FontRenderContext(null, true, true);
		Rectangle2D bounds = font.getStringBounds(errorText, frc);
		int w = (int) bounds.getWidth();
		int h = (int) bounds.getHeight();

		// create a BufferedImage object
		BufferedImage image = new BufferedImage(w, h,
				BufferedImage.TYPE_INT_RGB);
		Graphics2D g = image.createGraphics();

		// set color and other parameters
		g.setColor(Color.WHITE);
		g.fillRect(0, 0, w, h);
		g.setColor(Color.RED);
		g.setFont(font);

		g.drawString(errorText, (float) bounds.getX(), (float) -bounds.getY());

		g.dispose();
		return new ImageIcon(image, "ERROR");
	}

}