/*
    * Copyright 2002-2014 the original author or authors.
    *
    * 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 org.springframework.mock.web.test;
  
  import java.io.Serializable;
  import java.util.Collections;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.LinkedHashMap;
  import java.util.LinkedHashSet;
  import java.util.Map;
  import javax.servlet.ServletContext;
  import javax.servlet.http.HttpSession;
  import javax.servlet.http.HttpSessionBindingEvent;
  import javax.servlet.http.HttpSessionBindingListener;
  import javax.servlet.http.HttpSessionContext;
  
  import org.springframework.util.Assert;
  
  /**
   * Mock implementation of the {@link javax.servlet.http.HttpSession} interface.
   *
   * <p>As of Spring 4.0, this set of mocks is designed on a Servlet 3.0 baseline.
   *
   * <p>Used for testing the web framework; also useful for testing application
   * controllers.
   *
   * @author Juergen Hoeller
   * @author Rod Johnson
   * @author Mark Fisher
   * @author Sam Brannen
   * @since 1.0.2
   */
  @SuppressWarnings("deprecation")
  public class MockHttpSession implements HttpSession {
  
  	public static final String SESSION_COOKIE_NAME = "JSESSION";
  
  
  	private static int nextId = 1;
  
  	private String id;
  
  	private final long creationTime = System.currentTimeMillis();
  
  	private int maxInactiveInterval;
  
  	private long lastAccessedTime = System.currentTimeMillis();
  
  	private final ServletContext servletContext;
  
  	private final Map<String, Object> attributes = new LinkedHashMap<String, Object>();
  
  	private boolean invalid = false;
  
  	private boolean isNew = true;
  
  
  	/**
  	 * Create a new MockHttpSession with a default {@link MockServletContext}.
  	 *
  	 * @see MockServletContext
  	 */
  	public MockHttpSession() {
  		this(null);
  	}
  
  	/**
  	 * Create a new MockHttpSession.
  	 *
  	 * @param servletContext the ServletContext that the session runs in
  	 */
  	public MockHttpSession(ServletContext servletContext) {
  		this(servletContext, null);
  	}
  
  	/**
  	 * Create a new MockHttpSession.
  	 *
  	 * @param servletContext the ServletContext that the session runs in
  	 * @param id a unique identifier for this session
  	 */
  	public MockHttpSession(ServletContext servletContext, String id) {
  		this.servletContext = (servletContext != null ? servletContext : new MockServletContext());
 		this.id = (id != null ? id : Integer.toString(nextId++));
 	}
 
 	@Override
 	public long getCreationTime() {
 		assertIsValid();
 		return this.creationTime;
 	}
 
 	@Override
 	public String getId() {
 		return this.id;
 	}
 
 	/**
 	 * As of Servlet 3.1 the id of a session can be changed.
 	 * @return the new session id.
 	 * @since 4.0.3
 	 */
 	public String changeSessionId() {
 		this.id = Integer.toString(nextId++);
 		return this.id;
 	}
 
 	public void access() {
 		this.lastAccessedTime = System.currentTimeMillis();
 		this.isNew = false;
 	}
 
 	@Override
 	public long getLastAccessedTime() {
 		assertIsValid();
 		return this.lastAccessedTime;
 	}
 
 	@Override
 	public ServletContext getServletContext() {
 		return this.servletContext;
 	}
 
 	@Override
 	public void setMaxInactiveInterval(int interval) {
 		this.maxInactiveInterval = interval;
 	}
 
 	@Override
 	public int getMaxInactiveInterval() {
 		return this.maxInactiveInterval;
 	}
 
 	@Override
 	public HttpSessionContext getSessionContext() {
 		throw new UnsupportedOperationException("getSessionContext");
 	}
 
 	@Override
 	public Object getAttribute(String name) {
 		assertIsValid();
 		Assert.notNull(name, "Attribute name must not be null");
 		return this.attributes.get(name);
 	}
 
 	@Override
 	public Object getValue(String name) {
 		return getAttribute(name);
 	}
 
 	@Override
 	public Enumeration<String> getAttributeNames() {
 		assertIsValid();
 		return Collections.enumeration(new LinkedHashSet<String>(this.attributes.keySet()));
 	}
 
 	@Override
 	public String[] getValueNames() {
 		assertIsValid();
 		return this.attributes.keySet().toArray(new String[this.attributes.size()]);
 	}
 
 	@Override
 	public void setAttribute(String name, Object value) {
 		assertIsValid();
 		Assert.notNull(name, "Attribute name must not be null");
 		if (value != null) {
 			this.attributes.put(name, value);
 			if (value instanceof HttpSessionBindingListener) {
 				((HttpSessionBindingListener) value).valueBound(new HttpSessionBindingEvent(this, name, value));
 			}
 		}
 		else {
 			removeAttribute(name);
 		}
 	}
 
 	@Override
 	public void putValue(String name, Object value) {
 		setAttribute(name, value);
 	}
 
 	@Override
 	public void removeAttribute(String name) {
 		assertIsValid();
 		Assert.notNull(name, "Attribute name must not be null");
 		Object value = this.attributes.remove(name);
 		if (value instanceof HttpSessionBindingListener) {
 			((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
 		}
 	}
 
 	@Override
 	public void removeValue(String name) {
 		removeAttribute(name);
 	}
 
 	/**
 	 * Clear all of this session's attributes.
 	 */
 	public void clearAttributes() {
 		for (Iterator<Map.Entry<String, Object>> it = this.attributes.entrySet().iterator(); it.hasNext();) {
 			Map.Entry<String, Object> entry = it.next();
 			String name = entry.getKey();
 			Object value = entry.getValue();
 			it.remove();
 			if (value instanceof HttpSessionBindingListener) {
 				((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
 			}
 		}
 	}
 
 	/**
 	 * Invalidates this session then unbinds any objects bound to it.
 	 *
 	 * @throws IllegalStateException if this method is called on an already invalidated session
 	 */
 	@Override
 	public void invalidate() {
 		assertIsValid();
 		this.invalid = true;
 		clearAttributes();
 	}
 
 	public boolean isInvalid() {
 		return this.invalid;
 	}
 
 	/**
 	 * Convenience method for asserting that this session has not been
 	 * {@linkplain #invalidate() invalidated}.
 	 *
 	 * @throws IllegalStateException if this session has been invalidated
 	 */
 	private void assertIsValid() {
 		if (isInvalid()) {
 			throw new IllegalStateException("The session has already been invalidated");
 		}
 	}
 
 	public void setNew(boolean value) {
 		this.isNew = value;
 	}
 
 	@Override
 	public boolean isNew() {
 		assertIsValid();
 		return this.isNew;
 	}
 
 	/**
 	 * Serialize the attributes of this session into an object that can be
 	 * turned into a byte array with standard Java serialization.
 	 *
 	 * @return a representation of this session's serialized state
 	 */
 	public Serializable serializeState() {
 		HashMap<String, Serializable> state = new HashMap<String, Serializable>();
 		for (Iterator<Map.Entry<String, Object>> it = this.attributes.entrySet().iterator(); it.hasNext();) {
 			Map.Entry<String, Object> entry = it.next();
 			String name = entry.getKey();
 			Object value = entry.getValue();
 			it.remove();
 			if (value instanceof Serializable) {
 				state.put(name, (Serializable) value);
 			}
 			else {
 				// Not serializable... Servlet containers usually automatically
 				// unbind the attribute in this case.
 				if (value instanceof HttpSessionBindingListener) {
 					((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
 				}
 			}
 		}
 		return state;
 	}
 
 	/**
 	 * Deserialize the attributes of this session from a state object created by
 	 * {@link #serializeState()}.
 	 *
 	 * @param state a representation of this session's serialized state
 	 */
 	@SuppressWarnings("unchecked")
 	public void deserializeState(Serializable state) {
 		Assert.isTrue(state instanceof Map, "Serialized state needs to be of type [java.util.Map]");
 		this.attributes.putAll((Map<String, Object>) state);
 	}
 
 }