gourmetj-springboot/src/main/java/com/mousetech/gourmetj/JSFUtils.java

package com.mousetech.gourmetj;

import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.HashMap;
import java.util.Map;
import java.util.stream.Collectors;

import jakarta.faces.application.FacesMessage;
import jakarta.faces.context.ExternalContext;
import jakarta.faces.context.FacesContext;
import jakarta.faces.context.Flash;
import jakarta.servlet.http.Cookie;
import jakarta.servlet.http.HttpSession;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class JSFUtils {

	/* Logger */

	private static final Logger log =
			LoggerFactory.getLogger(JSFUtils.class);

	private static ExternalContext getExternalContext() {
		FacesContext facesContext =
				FacesContext.getCurrentInstance();
		ExternalContext externalContext =
				facesContext.getExternalContext();
		return externalContext;
	}

	/**
	 * Obtain resource as Stream. The caller must close this
	 * stream after use.
	 * 
	 * @param pathName Path of the resource. For example,
	 *                 "/WEB-INF/classes/xys.properties".
	 * @return InputStream or <code>null</code>, if no such
	 *         resource exists.
	 */
	public static InputStream getResourceStream(
			String pathName) {
		InputStream response = getExternalContext()
			.getResourceAsStream(pathName);
		return response;
	}

	// ===
	/**
	 * Post an info-level message to the FacesContext where the
	 * &lt;h:messages&gt; tag can display it.
	 * 
	 * @param string Message text
	 */
	public static void addInfoMessage(String string) {
		FacesMessage message = new FacesMessage(
				FacesMessage.SEVERITY_INFO, string, string);
		FacesContext.getCurrentInstance().addMessage(null,
			message);
	}


	public static void addWarningMessage(String msgString) {
		FacesMessage message = new FacesMessage(
			FacesMessage.SEVERITY_WARN, "WARNING", msgString);
		FacesContext.getCurrentInstance().addMessage(null,
			message);
	}	
	
	/**
	 * Post an error-level message to the FacesContext where the
	 * &lt;h:messages&gt; tag can display it.
	 * 
	 * @param string Message text
	 */
	public static void addErrorMessage(String string) {
		FacesMessage message = new FacesMessage(
				FacesMessage.SEVERITY_ERROR, string, string);
		FacesContext.getCurrentInstance().addMessage(null,
			message);
	}

	public static void addErrorMessage(String string,
			Exception e) {
		if (e instanceof NullPointerException) {
			addErrorMessage(
				"Internal logic error (NullPointerException)");
		} else {
			addErrorMessage(string);
		}
		log.error(string, e);
	}

	public static Flash flashScope() {
		return (FacesContext.getCurrentInstance()
			.getExternalContext().getFlash());
	}

	/**
	 * Look in Flash scope for item.
	 * 
	 * @param key Item to retrieve
	 * @return Item, or null if not in Flash OR Flash not active 
	 */
	public static Object getFlash(String key) {
		Flash flash = flashScope();
		try {
			return flash.get(key);
		} catch ( NullPointerException nex ) {
			// If session is expired, flash.get() will fail!
			return null;
		}
	}

	public static void putFlash(String key, Object value) {
		flashScope().put(key, value);
	}

	//***********
	//* COOKIE!!!
	//***********
	
	/**
	 * Get cookie values.
	 */
	public static Map<String, String> getCookies(){
		Map<String, Object> m0 = getExternalContext().getRequestCookieMap();
		Map<String, String>m1 = new HashMap<String, String>();
		m1 = m0.entrySet()
				.stream()
				.collect(Collectors.toMap(
					e -> e.getKey(),
					e -> ((Cookie)e.getValue()).getValue()));
		return m1;
	}

	/**
	 * Set a cookie value in Response.
	 * @param name Cookie name
	 * @param value Cookie value
	 * @param properties Cookie property Map (timeout, <i>etc.</i>)
	 * @throws UnsupportedEncodingException 
	 */
	public static void outputCookie(String name,
			String value, Map<String, Object> properties) throws UnsupportedEncodingException {
		getExternalContext().addResponseCookie(name,
			URLEncoder.encode(value, "UTF-8"),			
			properties);
	}

	/**
	 * Destroy current session, logging user out.
	 */
	public static void logout() {
		log.warn("Logging out session");
		jakarta.servlet.http.HttpSession session =
				(HttpSession) getExternalContext().getSession(false);
		if ( session != null ) {
			session.invalidate();
		} else {
			log.warn("Session did not exist.");
		}
		
	}

	public static HttpSession getSession(boolean create) {
		return (HttpSession) getExternalContext().getSession(create);
	}		
}