/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you 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.apache.shiro.guice.web;

 import java.util.Collection;

 import java.util.HashMap;

 import java.util.LinkedHashMap;

 import java.util.Map;

 import javax.servlet.Filter;

 import javax.servlet.ServletContext;

 import org.apache.shiro.config.ConfigurationException;

 import org.apache.shiro.env.Environment;

 import org.apache.shiro.guice.ShiroModule;

 import org.apache.shiro.mgt.SecurityManager;

 import org.apache.shiro.session.mgt.SessionManager;

 import org.apache.shiro.web.env.WebEnvironment;

 import org.apache.shiro.web.filter.PathMatchingFilter;

 import org.apache.shiro.web.filter.authc.AnonymousFilter;

 import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;

 import org.apache.shiro.web.filter.authc.FormAuthenticationFilter;

 import org.apache.shiro.web.filter.authc.LogoutFilter;

 import org.apache.shiro.web.filter.authc.UserFilter;

 import org.apache.shiro.web.filter.authz.HttpMethodPermissionFilter;

 import org.apache.shiro.web.filter.authz.PermissionsAuthorizationFilter;

 import org.apache.shiro.web.filter.authz.PortFilter;

 import org.apache.shiro.web.filter.authz.RolesAuthorizationFilter;

 import org.apache.shiro.web.filter.authz.SslFilter;

 import org.apache.shiro.web.filter.mgt.FilterChainResolver;

 import org.apache.shiro.web.filter.session.NoSessionCreationFilter;

 import org.apache.shiro.web.mgt.DefaultWebSecurityManager;

 import org.apache.shiro.web.mgt.WebSecurityManager;

 import org.apache.shiro.web.session.mgt.ServletContainerSessionManager;

 import com.google.inject.Binder;

 import com.google.inject.Key;

 import com.google.inject.TypeLiteral;

 import com.google.inject.binder.AnnotatedBindingBuilder;

 import com.google.inject.name.Names;

 import com.google.inject.servlet.ServletModule;

 /**

  * Sets up Shiro lifecycles within Guice, enables the injecting of Shiro objects, and binds a default

  * {@link org.apache.shiro.web.mgt.WebSecurityManager}, {@link org.apache.shiro.mgt.SecurityManager} and {@link org.apache.shiro.session.mgt.SessionManager}.  At least one realm must be added by

  * using {@link #bindRealm() bindRealm}.

  * <p/>

  * Also provides for the configuring of filter chains and binds a {@link org.apache.shiro.web.filter.mgt.FilterChainResolver} with that information.

  */

 public abstract class ShiroWebModule extends ShiroModule {

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<AnonymousFilter> ANON = Key.get(AnonymousFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<FormAuthenticationFilter> AUTHC = Key.get(FormAuthenticationFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<BasicHttpAuthenticationFilter> AUTHC_BASIC = Key.get(BasicHttpAuthenticationFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<NoSessionCreationFilter> NO_SESSION_CREATION = Key.get(NoSessionCreationFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<LogoutFilter> LOGOUT = Key.get(LogoutFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<PermissionsAuthorizationFilter> PERMS = Key.get(PermissionsAuthorizationFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<PortFilter> PORT = Key.get(PortFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<HttpMethodPermissionFilter> REST = Key.get(HttpMethodPermissionFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<RolesAuthorizationFilter> ROLES = Key.get(RolesAuthorizationFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<SslFilter> SSL = Key.get(SslFilter.class);

     @SuppressWarnings({"UnusedDeclaration"})

     public static final Key<UserFilter> USER = Key.get(UserFilter.class);

     static final String NAME = "SHIRO";

     /**

      * We use a LinkedHashMap here to ensure that iterator order is the same as add order.  This is important, as the

      * FilterChainResolver uses iterator order when searching for a matching chain.

      */

     private final Map<String, Key<? extends Filter>[]> filterChains = new LinkedHashMap<String, Key<? extends Filter>[]>();

     private final ServletContext servletContext;

     public ShiroWebModule(ServletContext servletContext) {

         this.servletContext = servletContext;

     }

     public static void bindGuiceFilter(Binder binder) {

         binder.install(guiceFilterModule());

     }

     @SuppressWarnings({"UnusedDeclaration"})

     public static void bindGuiceFilter(final String pattern, Binder binder) {

         binder.install(guiceFilterModule(pattern));

     }

     public static ServletModule guiceFilterModule() {

         return guiceFilterModule("/*");

     }

     public static ServletModule guiceFilterModule(final String pattern) {

         return new ServletModule() {

             @Override

             protected void configureServlets() {

                 filter(pattern).through(GuiceShiroFilter.class);

             }

         };

     }

     @Override

     protected final void configureShiro() {

         bindBeanType(TypeLiteral.get(ServletContext.class), Key.get(ServletContext.class, Names.named(NAME)));

         bind(Key.get(ServletContext.class, Names.named(NAME))).toInstance(this.servletContext);

         bindWebSecurityManager(bind(WebSecurityManager.class));

         bindWebEnvironment(bind(WebEnvironment.class));

         bind(GuiceShiroFilter.class).asEagerSingleton();

         expose(GuiceShiroFilter.class);

         this.configureShiroWeb();

         setupFilterChainConfigs();

         bind(FilterChainResolver.class).toProvider(new FilterChainResolverProvider(filterChains));

     }

     private void setupFilterChainConfigs() {

         Map<Key<? extends PathMatchingFilter>, Map<String, String>> configs = new HashMap<Key<? extends PathMatchingFilter>, Map<String, String>>();

         for (Map.Entry<String, Key<? extends Filter>[]> filterChain : filterChains.entrySet()) {

             for (int i = 0; i < filterChain.getValue().length; i++) {

                 Key<? extends Filter> key = filterChain.getValue()[i];

                 if (key instanceof FilterConfigKey) {

                     FilterConfigKey<? extends PathMatchingFilter> configKey = (FilterConfigKey<? extends PathMatchingFilter>) key;

                     key = configKey.getKey();

                     filterChain.getValue()[i] = key;

                     if (!PathMatchingFilter.class.isAssignableFrom(key.getTypeLiteral().getRawType())) {

                         throw new ConfigurationException("Config information requires a PathMatchingFilter - can't apply to " + key.getTypeLiteral().getRawType());

                     }

                     if (configs.get(castToPathMatching(key)) == null) configs.put(castToPathMatching(key), new HashMap<String, String>());

                     configs.get(castToPathMatching(key)).put(filterChain.getKey(), configKey.getConfigValue());

                 } else if (PathMatchingFilter.class.isAssignableFrom(key.getTypeLiteral().getRawType())) {

                           if (configs.get(castToPathMatching(key)) == null) configs.put(castToPathMatching(key), new HashMap<String, String>());

                     configs.get(castToPathMatching(key)).put(filterChain.getKey(), "");

                 }

             }

         }

         for (Key<? extends PathMatchingFilter> filterKey : configs.keySet()) {

             bindPathMatchingFilter(filterKey, configs.get(filterKey));

         }

     }

     private <T extends PathMatchingFilter> void bindPathMatchingFilter(Key<T> filterKey, Map<String, String> configs) {

         bind(filterKey).toProvider(new PathMatchingFilterProvider<T>(filterKey, configs)).asEagerSingleton();

     }

     @SuppressWarnings({"unchecked"})

     private Key<? extends PathMatchingFilter> castToPathMatching(Key<? extends Filter> key) {

         return (Key<? extends PathMatchingFilter>) key;

     }

     protected abstract void configureShiroWeb();

     @SuppressWarnings({"unchecked"})

     @Override

     protected final void bindSecurityManager(AnnotatedBindingBuilder<? super SecurityManager> bind) {

         bindWebSecurityManager(bind);

     }

     /**

      * Binds the security manager.  Override this method in order to provide your own security manager binding.

      * <p/>

      * By default, a {@link org.apache.shiro.web.mgt.DefaultWebSecurityManager} is bound as an eager singleton.

      *

      * @param bind

      */

     protected void bindWebSecurityManager(AnnotatedBindingBuilder<? super WebSecurityManager> bind) {

         try {

             bind.toConstructor(DefaultWebSecurityManager.class.getConstructor(Collection.class)).asEagerSingleton();

         } catch (NoSuchMethodException e) {

             throw new ConfigurationException("This really shouldn't happen.  Either something has changed in Shiro, or there's a bug in ShiroModule.", e);

         }

     }

     /**

      * Binds the session manager.  Override this method in order to provide your own session manager binding.

      * <p/>

      * By default, a {@link org.apache.shiro.web.session.mgt.DefaultWebSessionManager} is bound as an eager singleton.

      *

      * @param bind

      */

     @Override

     protected void bindSessionManager(AnnotatedBindingBuilder<SessionManager> bind) {

         bind.to(ServletContainerSessionManager.class).asEagerSingleton();

     }

     @Override

     protected final void bindEnvironment(AnnotatedBindingBuilder<Environment> bind) {

         bindWebEnvironment(bind);

     }

     protected void bindWebEnvironment(AnnotatedBindingBuilder<? super WebEnvironment> bind) {

         bind.to(WebGuiceEnvironment.class).asEagerSingleton();

     }

     /**

      * Adds a filter chain to the shiro configuration.

      * <p/>

      * NOTE: If the provided key is for a subclass of {@link org.apache.shiro.web.filter.PathMatchingFilter}, it will be registered with a proper

      * provider.

      *

      * @param pattern

      * @param keys

      */

     @SuppressWarnings({"UnusedDeclaration"})

     protected final void addFilterChain(String pattern, Key<? extends Filter>... keys) {

         filterChains.put(pattern, keys);

     }

     protected static <T extends PathMatchingFilter> Key<T> config(Key<T> baseKey, String configValue) {

         return new FilterConfigKey<T>(baseKey, configValue);

     }

     @SuppressWarnings({"UnusedDeclaration"})

     protected static <T extends PathMatchingFilter> Key<T> config(TypeLiteral<T> typeLiteral, String configValue) {

         return config(Key.get(typeLiteral), configValue);

     }

     @SuppressWarnings({"UnusedDeclaration"})

     protected static <T extends PathMatchingFilter> Key<T> config(Class<T> type, String configValue) {

         return config(Key.get(type), configValue);

     }

     private static class FilterConfigKey<T extends PathMatchingFilter> extends Key<T> {

         private Key<T> key;

         private String configValue;

         private FilterConfigKey(Key<T> key, String configValue) {

             super();

             this.key = key;

             this.configValue = configValue;

         }

         public Key<T> getKey() {

             return key;

         }

         public String getConfigValue() {

             return configValue;

         }

     }

 }