envoy/src/main/java/envoy/client/ui/IconUtil.java

package envoy.client.ui;

import java.util.EnumMap;
import java.util.EnumSet;
import java.util.logging.Level;

import javafx.scene.image.Image;

import envoy.client.data.Settings;
import envoy.util.EnvoyLog;

/**
 * Provides static utility methods for loading icons from the resource
 * folder.
 * <p>
 * Project: <strong>envoy-client</strong><br>
 * File: <strong>IconUtil.java</strong><br>
 * Created: <strong>16.03.2020</strong><br>
 *
 * @author Kai S. K. Engelbart
 * @since Envoy Client v0.1-beta
 */
public class IconUtil {

	private IconUtil() {}

	/**
	 * Loads an icon from the resource folder.
	 *
	 * @param path the path to the icon inside the resource folder
	 * @return the icon
	 * @since Envoy Client v0.1-beta
	 */
	public static Image load(String path) {
		Image image;
		try {
			image = new Image(IconUtil.class.getResource(path).toExternalForm());
		} catch (final NullPointerException e) {
			EnvoyLog.getLogger(IconUtil.class).log(Level.WARNING, String.format("Could not load image at path %s: ", path), e);
			throw e;
		}
		return image;
	}

	/**
	 * Loads an icon from the resource folder and scales it to a given size.
	 *
	 * @param path the path to the icon inside the resource folder
	 * @param size the size to scale the icon to
	 * @return the scaled icon
	 * @since Envoy Client v0.1-beta
	 */
	public static Image load(String path, int size) {
		Image image;
		try {
			image = new Image(IconUtil.class.getResource(path).toExternalForm(), size, size, true, true);
		} catch (final NullPointerException e) {
			EnvoyLog.getLogger(IconUtil.class).log(Level.WARNING, String.format("Could not load image at path %s: ", path), e);
			throw e;
		}
		return image;
	}

	/**
	 * Loads a {@code .png} icon from the sub-folder {@code /icons/} of the resource
	 * folder and scales it to 16px.<br>
	 * The suffix {@code .png} is automatically appended.
	 *
	 * @param name the image name without the .png - suffix
	 * @return the loaded image
	 * @since Envoy Client v0.1-beta
	 * @apiNote let's take a sample image {@code abc.png} in the folder
	 *          {@code /icons/}.
	 *          <br>
	 *          To do that, we only have to call
	 *          {@code IconUtil.loadDefault("abc")}
	 */
	public static Image loadDefault(String name) { return load("/icons/" + name + ".png"); }

	/**
	 * Loads a {@code .png} icon from the sub-folder {@code /icons/} of the resource
	 * folder and scales it to a given size.<br>
	 * The suffix {@code .png} is automatically appended.
	 *
	 * @param name the image name without the .png - suffix
	 * @param size the size of the image to scale to
	 * @return the loaded image
	 * @since Envoy Client v0.1-beta
	 * @apiNote let's take a sample image {@code abc.png} in the folder
	 *          {@code /icons/} and load it in size 16.
	 *          <br>
	 *          To do that, we only have to call
	 *          {@code IconUtil.loadDefault("abc", 16)}
	 */
	public static Image loadDefault(String name, int size) { return load("/icons/" + name + ".png", size); }

	/**
	 * Loads a {@code .png} icon whose design depends on the currently active theme
	 * from the sub-folder {@code /icons/} of the resource folder.
	 * <p>
	 * In case of the dark theme, the suffix {@code "white"} will be appended, else
	 * the suffix {@code "black"} will be appended.
	 * <p>
	 * The suffix {@code .png} is automatically appended.
	 *
	 * @param name the image name without the "black" or "white" suffix and without
	 *             the .png - suffix
	 * @return the loaded image
	 * @since Envoy Client v0.1-beta
	 * @apiNote let's take two sample images {@code abc_black.png} and
	 *          {@code abc_white.png} in the folder {@code /icons/} and load them.
	 *          <br>
	 *          To do that theme sensitve, we only have to call
	 *          {@code IconUtil.loadDefaultThemeSensitive("abc_")}
	 */
	public static Image loadDefaultThemeSensitive(String name) { return loadDefault(name + themeSpecificSuffix()); }

	/**
	 * Loads a {@code .png} icon whose design depends on the currently active theme
	 * from the sub-folder {@code /icons/} of the resource
	 * folder and scales it to the given size.
	 * <p>
	 * In case of the dark theme, the suffix {@code "white"} will be appended, else
	 * the suffix {@code "black"} will be appended.
	 * <p>
	 * The suffix {@code .png} is automatically appended.
	 *
	 * @param name the image name without the .png - suffix
	 * @param size the size of the image to scale to
	 * @return the loaded image
	 * @since Envoy Client v0.1-beta
	 * @apiNote let's take two sample images {@code abc_black.png} and
	 *          {@code abc_white.png} in the folder {@code /icons/} and load it in
	 *          size 16.
	 *          <br>
	 *          To do that theme sensitve, we only have to call
	 *          {@code IconUtil.loadDefaultThemeSensitive("abc_", 16)}
	 */
	public static Image loadDefaultThemeSensitive(String name, int size) { return loadDefault(name + themeSpecificSuffix(), size); }

	/**
	 *
	 * Loads icons specified by an enum. The images have to be named like the
	 * lowercase enum constants with {@code .png} extension and be located inside a
	 * folder with the lowercase name of the enum, which must be contained inside
	 * the {@code /icons} folder.
	 *
	 * @param <T>       the enum that specifies the icons to load
	 * @param enumClass the class of the enum
	 * @param size      the size to scale the icons to
	 * @return a map containing the loaded icons with the corresponding enum
	 *         constants as keys
	 * @since Envoy Client v0.1-beta
	 */
	public static <T extends Enum<T>> EnumMap<T, Image> loadByEnum(Class<T> enumClass, int size) {
		final var	icons	= new EnumMap<T, Image>(enumClass);
		final var	path	= "/icons/" + enumClass.getSimpleName().toLowerCase() + "/";
		for (final var e : EnumSet.allOf(enumClass))
			icons.put(e, load(path + e.toString().toLowerCase() + ".png", size));
		return icons;
	}

	/**
	 * This method should be called if the display of an icon depends upon the
	 * currently active theme.<br>
	 * In case of the dark theme, the suffix {@code "white"} will be appended, else
	 * the suffix {@code "black"} will be appended.
	 *
	 * @return the theme specific suffix
	 * @since Envoy Client v0.1-beta
	 */
	public static String themeSpecificSuffix() { return Settings.getInstance().getCurrentTheme().equals("dark") ? "white" : "black"; }
}