package envoy.client.data.shortcuts;

import java.util.*;

import javafx.scene.input.KeyCombination;

import envoy.client.ui.SceneContext.SceneInfo;

/**
 * Contains all keyboard shortcuts used throughout the application.
 *
 * @author Leon Hofmeister
 * @since Envoy Client v0.3-beta
 */
public final class GlobalKeyShortcuts {

	private final EnumMap<SceneInfo, Map<KeyCombination, Runnable>> shortcuts =
		new EnumMap<>(SceneInfo.class);

	private static GlobalKeyShortcuts instance = new GlobalKeyShortcuts();

	private GlobalKeyShortcuts() {
		for (final var sceneInfo : SceneInfo.values())
			shortcuts.put(sceneInfo, new HashMap<KeyCombination, Runnable>());
	}

	/**
	 * @return the instance of global keyboard shortcuts.
	 * @since Envoy Client v0.3-beta
	 */
	public static GlobalKeyShortcuts getInstance() { return instance; }

	/**
	 * Adds the given keyboard shortcut and its action to all scenes.
	 *
	 * @param keys   the keys to press to perform the given action
	 * @param action the action to perform
	 * @since Envoy Client v0.3-beta
	 */
	public void add(KeyCombination keys, Runnable action) {
		shortcuts.values().forEach(collection -> collection.put(keys, action));
	}

	/**
	 * Adds the given keyboard shortcut and its action to all scenes that are not part of exclude.
	 *
	 * @param keys    the keys to press to perform the given action
	 * @param action  the action to perform
	 * @param exclude the scenes that should be excluded from receiving this keyboard shortcut
	 * @since Envoy Client v0.3-beta
	 */
	public void addForNotExcluded(KeyCombination keys, Runnable action, SceneInfo... exclude) {

		// Computing the remaining sceneInfos
		final var	include	= new SceneInfo[SceneInfo.values().length - exclude.length];
		int			index	= 0;
		outer: for (final var sceneInfo : SceneInfo.values()) {
			for (final var excluded : exclude)
				if (sceneInfo.equals(excluded))
					continue outer;
			include[index++] = sceneInfo;
		}

		// Adding the action to the remaining sceneInfos
		for (final var sceneInfo : include)
			shortcuts.get(sceneInfo).put(keys, action);
	}

	/**
	 * Returns all stored keyboard shortcuts for the given scene constant.
	 *
	 * @param sceneInfo the currently loading scene
	 * @return all stored keyboard shortcuts for this scene
	 * @since Envoy Client v0.3-beta
	 */
	public Map<KeyCombination, Runnable> getKeyboardShortcuts(SceneInfo sceneInfo) {
		return shortcuts.get(sceneInfo);
	}
}