/*
 * 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.catalina.startup;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.security.Principal;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.logging.Level;
import java.util.logging.LogManager;
import java.util.logging.Logger;

import jakarta.servlet.Servlet;
import jakarta.servlet.ServletException;
import jakarta.servlet.annotation.WebServlet;

import org.apache.catalina.Container;
import org.apache.catalina.Context;
import org.apache.catalina.Engine;
import org.apache.catalina.Globals;
import org.apache.catalina.Host;
import org.apache.catalina.Lifecycle;
import org.apache.catalina.LifecycleEvent;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.LifecycleListener;
import org.apache.catalina.Realm;
import org.apache.catalina.Server;
import org.apache.catalina.Service;
import org.apache.catalina.Wrapper;
import org.apache.catalina.authenticator.NonLoginAuthenticator;
import org.apache.catalina.connector.Connector;
import org.apache.catalina.core.ContainerBase;
import org.apache.catalina.core.NamingContextListener;
import org.apache.catalina.core.StandardContext;
import org.apache.catalina.core.StandardEngine;
import org.apache.catalina.core.StandardHost;
import org.apache.catalina.core.StandardServer;
import org.apache.catalina.core.StandardService;
import org.apache.catalina.core.StandardWrapper;
import org.apache.catalina.realm.GenericPrincipal;
import org.apache.catalina.realm.RealmBase;
import org.apache.catalina.util.ContextName;
import org.apache.catalina.util.IOTools;
import org.apache.tomcat.util.ExceptionUtils;
import org.apache.tomcat.util.buf.UriUtil;
import org.apache.tomcat.util.compat.JreCompat;
import org.apache.tomcat.util.descriptor.web.LoginConfig;
import org.apache.tomcat.util.file.ConfigFileLoader;
import org.apache.tomcat.util.file.ConfigurationSource;
import org.apache.tomcat.util.modeler.Registry;
import org.apache.tomcat.util.res.StringManager;

// TODO: lazy init for the temp dir - only when a JSP is compiled or
// get temp dir is called we need to create it. This will avoid the
// need for the baseDir

// TODO: allow contexts without a base dir - i.e.
// only programmatic. This would disable the default servlet.

/**
 * Minimal tomcat starter for embedding/unit tests.
 * <p>
 * Tomcat supports multiple styles of configuration and startup - the most common and stable is server.xml-based,
 * implemented in org.apache.catalina.startup.Bootstrap.
 * <p>
 * This class is for use in apps that embed tomcat.
 * <p>
 * Requirements:
 * <ul>
 * <li>all tomcat classes and possibly servlets are in the classpath. (for example all is in one big jar, or in eclipse
 * CP, or in any other combination)</li>
 * <li>we need one temporary directory for work files</li>
 * <li>no config file is required. This class provides methods to use if you have a webapp with a web.xml file, but it
 * is optional - you can use your own servlets.</li>
 * </ul>
 * <p>
 * There are a variety of 'add' methods to configure servlets and webapps. These methods, by default, create a simple
 * in-memory security realm and apply it. If you need more complex security processing, you can define a subclass of
 * this class.
 * <p>
 * This class provides a set of convenience methods for configuring web application contexts; all overloads of the
 * method <code>addWebapp()</code>. These methods are equivalent to adding a web application to the Host's appBase
 * (normally the webapps directory). These methods create a Context, configure it with the equivalent of the defaults
 * provided by <code>conf/web.xml</code> (see {@link #initWebappDefaults(String)} for details) and add the Context to a
 * Host. These methods do not use a global default web.xml; rather, they add a {@link LifecycleListener} to configure
 * the defaults. Any WEB-INF/web.xml and META-INF/context.xml packaged with the application will be processed normally.
 * Normal web fragment and {@link jakarta.servlet.ServletContainerInitializer} processing will be applied.
 * <p>
 * In complex cases, you may prefer to use the ordinary Tomcat API to create webapp contexts; for example, you might
 * need to install a custom Loader before the call to {@link Host#addChild(Container)}. To replicate the basic behavior
 * of the <code>addWebapp</code> methods, you may want to call two methods of this class: {@link #noDefaultWebXmlPath()}
 * and {@link #getDefaultWebXmlListener()}.
 * <p>
 * {@link #getDefaultWebXmlListener()} returns a {@link LifecycleListener} that adds the standard DefaultServlet, JSP
 * processing, and welcome files. If you add this listener, you must prevent Tomcat from applying any standard global
 * web.xml with ...
 * <p>
 * {@link #noDefaultWebXmlPath()} returns a dummy pathname to configure to prevent {@link ContextConfig} from trying to
 * apply a global web.xml file.
 * <p>
 * This class provides a main() and few simple CLI arguments, see setters for doc. It can be used for simple tests and
 * demo.
 *
 * @see <a href=
 *          "https://gitbox.apache.org/repos/asf?p=tomcat.git;a=blob;f=test/org/apache/catalina/startup/TestTomcat.java">TestTomcat</a>
 */
public class Tomcat {

    private static final StringManager sm = StringManager.getManager(Tomcat.class);

    // Some logging implementations use weak references for loggers so there is
    // the possibility that logging configuration could be lost if GC runs just
    // after Loggers are configured but before they are used. The purpose of
    // this Map is to retain strong references to explicitly configured loggers
    // so that configuration is not lost.
    private final Map<String,Logger> pinnedLoggers = new HashMap<>();

    protected Server server;

    protected int port = 8080;
    protected String hostname = "localhost";
    protected String basedir;

    private final Map<String,String> userPass = new HashMap<>();
    private final Map<String,List<String>> userRoles = new HashMap<>();
    private final Map<String,Principal> userPrincipals = new HashMap<>();

    private boolean addDefaultWebXmlToWebapp = true;

    public Tomcat() {
        ExceptionUtils.preload();
    }

    /**
     * Tomcat requires that the base directory is set because the defaults for a number of other locations, such as the
     * work directory, are derived from the base directory. This should be the first method called.
     * <p>
     * If this method is not called then Tomcat will attempt to use these locations in the following order:
     * <ol>
     * <li>if set, the catalina.base system property</li>
     * <li>if set, the catalina.home system property</li>
     * <li>The user.dir system property (the directory where Java was run from) where a directory named tomcat.$PORT
     * will be created. $PORT is the value configured via {@link #setPort(int)} which defaults to 8080 if not set</li>
     * </ol>
     * The user should ensure that the file permissions for the base directory are appropriate.
     * <p>
     * TODO: disable work dir if not needed ( no jsp, etc ).
     *
     * @param basedir The Tomcat base folder on which all others will be derived
     */
    public void setBaseDir(String basedir) {
        this.basedir = basedir;
    }

    /**
     * Set the port for the default connector. The default connector will only be created if getConnector is called.
     *
     * @param port The port number
     */
    public void setPort(int port) {
        this.port = port;
    }

    /**
     * The hostname of the default host, default is 'localhost'.
     *
     * @param s The default host name
     */
    public void setHostname(String s) {
        hostname = s;
    }


    /**
     * This is equivalent to adding a web application to a Host's appBase (usually Tomcat's webapps directory). By
     * default, the equivalent of the default web.xml will be applied to the web application (see
     * {@link #initWebappDefaults(String)}). This may be prevented by calling
     * {@link #setAddDefaultWebXmlToWebapp(boolean)} with {@code false}. Any <code>WEB-INF/web.xml</code> and
     * <code>META-INF/context.xml</code> packaged with the application will always be processed and normal web fragment
     * and {@link jakarta.servlet.ServletContainerInitializer} processing will always be applied.
     *
     * @param contextPath The context mapping to use, "" for root context.
     * @param docBase     Base directory for the context, for static files. Must exist and be an absolute path.
     *
     * @return the deployed context
     */
    public Context addWebapp(String contextPath, String docBase) {
        return addWebapp(getHost(), contextPath, docBase);
    }


    /**
     * Copy the specified WAR file to the Host's appBase and then call {@link #addWebapp(String, String)} with the newly
     * copied WAR. The WAR will <b>NOT</b> be removed from the Host's appBase when the Tomcat instance stops. Note that
     * {@link ExpandWar} provides utility methods that may be used to delete the WAR and/or expanded directory if
     * required.
     *
     * @param contextPath The context mapping to use, "" for root context.
     * @param source      The location from which the WAR should be copied
     *
     * @return The deployed Context
     *
     * @throws IOException If an I/O error occurs while copying the WAR file from the specified URL to the appBase
     */
    public Context addWebapp(String contextPath, URL source) throws IOException {

        ContextName cn = new ContextName(contextPath, null);

        // Make sure a conflicting web application has not already been deployed
        Host h = getHost();
        if (h.findChild(cn.getName()) != null) {
            throw new IllegalArgumentException(
                    sm.getString("tomcat.addWebapp.conflictChild", source, contextPath, cn.getName()));
        }

        // Make sure appBase does not contain a conflicting web application
        File targetWar = new File(h.getAppBaseFile(), cn.getBaseName() + ".war");
        File targetDir = new File(h.getAppBaseFile(), cn.getBaseName());

        if (targetWar.exists()) {
            throw new IllegalArgumentException(
                    sm.getString("tomcat.addWebapp.conflictFile", source, contextPath, targetWar.getAbsolutePath()));
        }
        if (targetDir.exists()) {
            throw new IllegalArgumentException(
                    sm.getString("tomcat.addWebapp.conflictFile", source, contextPath, targetDir.getAbsolutePath()));
        }

        // Should be good to copy the WAR now
        URLConnection uConn = source.openConnection();

        try (InputStream is = uConn.getInputStream(); OutputStream os = new FileOutputStream(targetWar)) {
            IOTools.flow(is, os);
        }

        return addWebapp(contextPath, targetWar.getAbsolutePath());
    }


    /**
     * Add a context - programmatic mode, no default web.xml used. This means that there is no JSP support (no JSP
     * servlet), no default servlet and no web socket support unless explicitly enabled via the programmatic interface.
     * There is also no {@link jakarta.servlet.ServletContainerInitializer} processing and no annotation processing. If
     * a {@link jakarta.servlet.ServletContainerInitializer} is added programmatically, there will still be no scanning
     * for {@link jakarta.servlet.annotation.HandlesTypes} matches.
     * <p>
     * API calls equivalent with web.xml:
     *
     * <pre>{@code
     * // context-param
     * ctx.addParameter("name", "value");
     *
     *
     * // error-page
     * ErrorPage ep = new ErrorPage();
     * ep.setErrorCode(500);
     * ep.setLocation("/error.html");
     * ctx.addErrorPage(ep);
     *
     * ctx.addMimeMapping("ext", "type");
     * }</pre>
     * <p>
     * Note: If you reload the Context, all your configuration will be lost. If you need reload support, consider using
     * a LifecycleListener to provide your configuration.
     * <p>
     * TODO: add the rest
     *
     * @param contextPath The context mapping to use, "" for root context.
     * @param docBase     Base directory for the context, for static files. Must exist, relative to the server home
     *
     * @return the deployed context
     */
    public Context addContext(String contextPath, String docBase) {
        return addContext(getHost(), contextPath, docBase);
    }

    /**
     * Equivalent to &lt;servlet&gt;&lt;servlet-name&gt;&lt;servlet-class&gt;.
     * <p>
     * In general it is better/faster to use the method that takes a Servlet as param - this one can be used if the
     * servlet is not commonly used, and want to avoid loading all deps. ( for example: jsp servlet ) You can customize
     * the returned servlet, ex:
     *
     * <pre>
     * wrapper.addInitParameter("name", "value");
     * </pre>
     *
     * @param contextPath  Context to add Servlet to
     * @param servletName  Servlet name (used in mappings)
     * @param servletClass The class to be used for the Servlet
     *
     * @return The wrapper for the servlet
     */
    public Wrapper addServlet(String contextPath, String servletName, String servletClass) {
        Container ctx = getHost().findChild(contextPath);
        return addServlet((Context) ctx, servletName, servletClass);
    }

    /**
     * Static version of {@link #addServlet(String, String, String)}
     *
     * @param ctx          Context to add Servlet to
     * @param servletName  Servlet name (used in mappings)
     * @param servletClass The class to be used for the Servlet
     *
     * @return The wrapper for the servlet
     */
    public static Wrapper addServlet(Context ctx, String servletName, String servletClass) {
        // will do class for name and set init params
        Wrapper sw = ctx.createWrapper();
        if (sw == null) {
            throw new IllegalStateException(sm.getString("tomcat.noWrapper"));
        }
        sw.setServletClass(servletClass);
        sw.setName(servletName);
        ctx.addChild(sw);

        return sw;
    }

    /**
     * Add an existing Servlet to the context with no class.forName or initialisation.
     *
     * @param contextPath Context to add Servlet to
     * @param servletName Servlet name (used in mappings)
     * @param servlet     The Servlet to add
     *
     * @return The wrapper for the servlet
     */
    public Wrapper addServlet(String contextPath, String servletName, Servlet servlet) {
        Container ctx = getHost().findChild(contextPath);
        return addServlet((Context) ctx, servletName, servlet);
    }

    /**
     * Static version of {@link #addServlet(String, String, Servlet)}.
     *
     * @param ctx         Context to add Servlet to
     * @param servletName Servlet name (used in mappings)
     * @param servlet     The Servlet to add
     *
     * @return The wrapper for the servlet
     */
    public static Wrapper addServlet(Context ctx, String servletName, Servlet servlet) {
        // will do class for name and set init params
        Wrapper sw = new ExistingStandardWrapper(servlet);
        sw.setName(servletName);
        ctx.addChild(sw);

        return sw;
    }


    /**
     * Initialize the server given the specified configuration source. The server will be loaded according to the Tomcat
     * configuration files contained in the source (server.xml, web.xml, context.xml, SSL certificates, etc). If no
     * configuration source is specified, it will use the default locations for these files.
     *
     * @param source The configuration source
     */
    public void init(ConfigurationSource source) {
        init(source, null);
    }

    /**
     * Initialize the server given the specified configuration source. The server will be loaded according to the Tomcat
     * configuration files contained in the source (server.xml, web.xml, context.xml, SSL certificates, etc). If no
     * configuration source is specified, it will use the default locations for these files.
     *
     * @param source            The configuration source
     * @param catalinaArguments The arguments that should be passed to Catalina
     */
    public void init(ConfigurationSource source, String[] catalinaArguments) {
        ConfigFileLoader.setSource(source);
        addDefaultWebXmlToWebapp = false;
        Catalina catalina = new Catalina();
        // Load the Catalina instance with the regular configuration files
        // from specified source
        if (catalinaArguments == null) {
            catalina.load();
        } else {
            catalina.load(catalinaArguments);
        }
        // Retrieve and set the server
        server = catalina.getServer();
    }


    /**
     * Initialize the server.
     *
     * @throws LifecycleException Init error
     */
    public void init() throws LifecycleException {
        getServer();
        server.init();
    }


    /**
     * Start the server.
     *
     * @throws LifecycleException Start error
     */
    public void start() throws LifecycleException {
        getServer();
        server.start();
    }

    /**
     * Stop the server.
     *
     * @throws LifecycleException Stop error
     */
    public void stop() throws LifecycleException {
        getServer();
        server.stop();
    }


    /**
     * Destroy the server. This object cannot be used once this method has been called.
     *
     * @throws LifecycleException Destroy error
     */
    public void destroy() throws LifecycleException {
        getServer();
        server.destroy();
        // Could null out objects here
    }

    /**
     * Add a user for the in-memory realm. All created apps use this by default, can be replaced using setRealm().
     *
     * @param user The username
     * @param pass The password
     */
    public void addUser(String user, String pass) {
        userPass.put(user, pass);
    }

    /**
     * Add a role to a user.
     *
     * @see #addUser(String, String)
     *
     * @param user The username
     * @param role The role name
     */
    public void addRole(String user, String role) {
        userRoles.computeIfAbsent(user, k -> new ArrayList<>()).add(role);
    }

    // ------- Extra customization -------
    // You can tune individual Tomcat objects, using internal APIs

    /**
     * Get the default HTTP connector that is used by the embedded Tomcat. It is first configured connector in the
     * service. If there's no connector defined, it will create and add a default connector using the port and address
     * specified in this Tomcat instance, and return it for further customization.
     *
     * @return The connector object
     */
    public Connector getConnector() {
        Service service = getService();
        if (service.findConnectors().length > 0) {
            return service.findConnectors()[0];
        }
        // The same as in standard Tomcat configuration.
        // This creates a NIO HTTP connector.
        Connector connector = new Connector("HTTP/1.1");
        connector.setPort(port);
        service.addConnector(connector);
        return connector;
    }

    /**
     * Set the specified connector in the service, if it is not already present.
     *
     * @param connector The connector instance to add
     */
    public void setConnector(Connector connector) {
        Service service = getService();
        boolean found = false;
        for (Connector serviceConnector : service.findConnectors()) {
            if (connector == serviceConnector) {
                found = true;
                break;
            }
        }
        if (!found) {
            service.addConnector(connector);
        }
    }

    /**
     * Get the service object. Can be used to add more connectors and few other global settings.
     *
     * @return The service
     */
    public Service getService() {
        return getServer().findServices()[0];
    }

    /**
     * Sets the current host - all future webapps will be added to this host. When tomcat starts, the host will be the
     * default host.
     *
     * @param host The current host
     */
    public void setHost(Host host) {
        Engine engine = getEngine();
        boolean found = false;
        for (Container engineHost : engine.findChildren()) {
            if (engineHost == host) {
                found = true;
                break;
            }
        }
        if (!found) {
            engine.addChild(host);
        }
    }

    public Host getHost() {
        Engine engine = getEngine();
        if (engine.findChildren().length > 0) {
            return (Host) engine.findChildren()[0];
        }

        Host host = new StandardHost();
        host.setName(hostname);
        getEngine().addChild(host);
        return host;
    }

    /**
     * Access to the engine, for further customization.
     *
     * @return The engine
     */
    public Engine getEngine() {
        Service service = getServer().findServices()[0];
        if (service.getContainer() != null) {
            return service.getContainer();
        }
        Engine engine = new StandardEngine();
        engine.setName("Tomcat");
        engine.setDefaultHost(hostname);
        engine.setRealm(createDefaultRealm());
        service.setContainer(engine);
        return engine;
    }

    /**
     * Get the server object. You can add listeners and few more customizations. JNDI is disabled by default.
     *
     * @return The Server
     */
    public Server getServer() {

        if (server != null) {
            return server;
        }

        System.setProperty("catalina.useNaming", "false");

        server = new StandardServer();

        initBaseDir();

        // Set configuration source
        ConfigFileLoader.setSource(new CatalinaBaseConfigurationSource(new File(basedir), null));

        server.setPort(-1);

        Service service = new StandardService();
        service.setName("Tomcat");
        server.addService(service);
        return server;
    }

    /**
     * @param host        The host in which the context will be deployed
     * @param contextPath The context mapping to use, "" for root context.
     * @param dir         Base directory for the context, for static files. Must exist, relative to the server home
     *
     * @return the deployed context
     *
     * @see #addContext(String, String)
     */
    public Context addContext(Host host, String contextPath, String dir) {
        return addContext(host, contextPath, contextPath, dir);
    }

    /**
     * @param host        The host in which the context will be deployed
     * @param contextPath The context mapping to use, "" for root context.
     * @param contextName The context name
     * @param dir         Base directory for the context, for static files. Must exist, relative to the server home
     *
     * @return the deployed context
     *
     * @see #addContext(String, String)
     */
    public Context addContext(Host host, String contextPath, String contextName, String dir) {
        silence(host, contextName);
        Context ctx = createContext(host, contextPath);
        ctx.setName(contextName);
        ctx.setPath(contextPath);
        ctx.setDocBase(dir);
        ctx.addLifecycleListener(new FixContextListener());

        if (host == null) {
            getHost().addChild(ctx);
        } else {
            host.addChild(ctx);
        }
        return ctx;
    }


    /**
     * This is equivalent to adding a web application to a Host's appBase (usually Tomcat's webapps directory). By
     * default, the equivalent of the default web.xml will be applied to the web application (see
     * {@link #initWebappDefaults(String)}). This may be prevented by calling
     * {@link #setAddDefaultWebXmlToWebapp(boolean)} with {@code false}. Any <code>WEB-INF/web.xml</code> and
     * <code>META-INF/context.xml</code> packaged with the application will always be processed and normal web fragment
     * and {@link jakarta.servlet.ServletContainerInitializer} processing will always be applied.
     *
     * @param host        The host in which the context will be deployed
     * @param contextPath The context mapping to use, "" for root context.
     * @param docBase     Base directory for the context, for static files. Must exist and be an absolute path.
     *
     * @return the deployed context
     */
    public Context addWebapp(Host host, String contextPath, String docBase) {
        LifecycleListener listener;
        try {
            Class<?> clazz = Class.forName(getHost().getConfigClass());
            listener = (LifecycleListener) clazz.getConstructor().newInstance();
        } catch (ReflectiveOperationException e) {
            // Wrap in IAE since we can't easily change the method signature
            // to throw the specific checked exceptions
            throw new IllegalArgumentException(e);
        }

        return addWebapp(host, contextPath, docBase, listener);
    }


    /**
     * This is equivalent to adding a web application to a Host's appBase (usually Tomcat's webapps directory). By
     * default, the equivalent of the default web.xml will be applied to the web application (see
     * {@link #initWebappDefaults(String)}). This may be prevented by calling
     * {@link #setAddDefaultWebXmlToWebapp(boolean)} with {@code false}. Any <code>WEB-INF/web.xml</code> and
     * <code>META-INF/context.xml</code> packaged with the application will always be processed and normal web fragment
     * and {@link jakarta.servlet.ServletContainerInitializer} processing will always be applied.
     *
     * @param host        The host in which the context will be deployed
     * @param contextPath The context mapping to use, "" for root context.
     * @param docBase     Base directory for the context, for static files. Must exist and be an absolute path.
     * @param config      Custom context configuration helper. Any configuration will be in addition to equivalent of
     *                        the default web.xml configuration described above.
     *
     * @return the deployed context
     */
    public Context addWebapp(Host host, String contextPath, String docBase, LifecycleListener config) {

        silence(host, contextPath);

        Context ctx = createContext(host, contextPath);
        ctx.setPath(contextPath);
        ctx.setDocBase(docBase);

        if (addDefaultWebXmlToWebapp) {
            ctx.addLifecycleListener(getDefaultWebXmlListener());
        }

        ctx.setConfigFile(getWebappConfigFile(docBase, contextPath));

        ctx.addLifecycleListener(config);

        if (addDefaultWebXmlToWebapp && (config instanceof ContextConfig)) {
            // prevent it from looking ( if it finds one - it'll have dup error )
            ((ContextConfig) config).setDefaultWebXml(noDefaultWebXmlPath());
        }

        if (host == null) {
            getHost().addChild(ctx);
        } else {
            host.addChild(ctx);
        }

        return ctx;
    }

    /**
     * Return a listener that provides the required configuration items for JSP processing. From the standard Tomcat
     * global web.xml. Pass this to {@link Context#addLifecycleListener(LifecycleListener)} and then pass the result of
     * {@link #noDefaultWebXmlPath()} to {@link ContextConfig#setDefaultWebXml(String)}.
     *
     * @return a listener object that configures default JSP processing.
     */
    public LifecycleListener getDefaultWebXmlListener() {
        return new DefaultWebXmlListener();
    }

    /**
     * @return a pathname to pass to {@link ContextConfig#setDefaultWebXml(String)} when using
     *             {@link #getDefaultWebXmlListener()}.
     */
    public String noDefaultWebXmlPath() {
        return Constants.NoDefaultWebXml;
    }

    // ---------- Helper methods and classes -------------------

    /**
     * Create an in-memory realm. You can replace it for contexts with a real one. The Realm created here will be added
     * to the Engine by default and may be replaced at the Engine level or over-ridden (as per normal Tomcat behaviour)
     * at the Host or Context level.
     *
     * @return a realm instance
     */
    protected Realm createDefaultRealm() {
        return new SimpleRealm();
    }


    private class SimpleRealm extends RealmBase {

        @Override
        protected String getPassword(String username) {
            return userPass.get(username);
        }

        @Override
        protected Principal getPrincipal(String username) {
            Principal p = userPrincipals.get(username);
            if (p == null) {
                String pass = userPass.get(username);
                if (pass != null) {
                    p = new GenericPrincipal(username, userRoles.get(username));
                    userPrincipals.put(username, p);
                }
            }
            return p;
        }
    }


    protected void initBaseDir() {
        String catalinaHome = System.getProperty(Globals.CATALINA_HOME_PROP);
        if (basedir == null) {
            basedir = System.getProperty(Globals.CATALINA_BASE_PROP);
        }
        if (basedir == null) {
            basedir = catalinaHome;
        }
        if (basedir == null) {
            // Create a temp dir.
            basedir = System.getProperty("user.dir") + "/tomcat." + port;
        }

        File baseFile = new File(basedir);
        if (baseFile.exists()) {
            if (!baseFile.isDirectory()) {
                throw new IllegalArgumentException(sm.getString("tomcat.baseDirNotDir", baseFile));
            }
        } else {
            if (!baseFile.mkdirs()) {
                // Failed to create base directory
                throw new IllegalStateException(sm.getString("tomcat.baseDirMakeFail", baseFile));
            }
            /*
             * If file permissions were going to be set on the newly created directory, this is the place to do it.
             * However, even simple calls such as File.setReadable(boolean,boolean) behaves differently on different
             * platforms. Therefore, setBaseDir documents that the user needs to do this.
             */
        }
        try {
            baseFile = baseFile.getCanonicalFile();
        } catch (IOException ioe) {
            baseFile = baseFile.getAbsoluteFile();
        }
        server.setCatalinaBase(baseFile);
        System.setProperty(Globals.CATALINA_BASE_PROP, baseFile.getPath());
        basedir = baseFile.getPath();

        if (catalinaHome == null) {
            server.setCatalinaHome(baseFile);
        } else {
            File homeFile = new File(catalinaHome);
            if (!homeFile.isDirectory() && !homeFile.mkdirs()) {
                // Failed to create home directory
                throw new IllegalStateException(sm.getString("tomcat.homeDirMakeFail", homeFile));
            }
            try {
                homeFile = homeFile.getCanonicalFile();
            } catch (IOException ioe) {
                homeFile = homeFile.getAbsoluteFile();
            }
            server.setCatalinaHome(homeFile);
        }
        System.setProperty(Globals.CATALINA_HOME_PROP, server.getCatalinaHome().getPath());
    }

    static final String[] silences = new String[] { "org.apache.coyote.http11.Http11NioProtocol",
            "org.apache.catalina.core.StandardService", "org.apache.catalina.core.StandardEngine",
            "org.apache.catalina.startup.ContextConfig", "org.apache.catalina.core.ApplicationContext",
            "org.apache.catalina.core.AprLifecycleListener", "org.apache.catalina.core.OpenSSLLifecycleListener" };

    private boolean silent = false;

    /**
     * Controls if the loggers will be silenced or not.
     *
     * @param silent <code>true</code> sets the log level to WARN for the loggers that log information on Tomcat start
     *                   up. This prevents the usual startup information being logged. <code>false</code> sets the log
     *                   level to the default level of INFO.
     */
    public void setSilent(boolean silent) {
        this.silent = silent;
        for (String s : silences) {
            Logger logger = Logger.getLogger(s);
            pinnedLoggers.put(s, logger);
            if (silent) {
                logger.setLevel(Level.WARNING);
            } else {
                logger.setLevel(Level.INFO);
            }
        }
    }

    private void silence(Host host, String contextPath) {
        String loggerName = getLoggerName(host, contextPath);
        Logger logger = Logger.getLogger(loggerName);
        pinnedLoggers.put(loggerName, logger);
        if (silent) {
            logger.setLevel(Level.WARNING);
        } else {
            logger.setLevel(Level.INFO);
        }
    }


    /**
     * By default, when calling addWebapp() to create a Context, the settings from the default web.xml are added to the
     * context. Calling this method with a <code>false</code> value prior to calling addWebapp() allows to opt out of
     * the default settings. In that event you will need to add the configurations yourself, either programmatically or
     * by using web.xml deployment descriptors.
     *
     * @param addDefaultWebXmlToWebapp <code>false</code> will prevent the class from automatically adding the default
     *                                     settings when calling addWebapp(). <code>true</code> will add the default
     *                                     settings and is the default behavior.
     *
     * @see #addWebapp(Host, String, String, LifecycleListener)
     */
    public void setAddDefaultWebXmlToWebapp(boolean addDefaultWebXmlToWebapp) {
        this.addDefaultWebXmlToWebapp = addDefaultWebXmlToWebapp;
    }


    /*
     * Uses essentially the same logic as {@link ContainerBase#logName()}.
     */
    private String getLoggerName(Host host, String contextName) {
        if (host == null) {
            host = getHost();
        }
        StringBuilder loggerName = new StringBuilder();
        loggerName.append(ContainerBase.class.getName());
        loggerName.append(".[");
        // Engine name
        loggerName.append(host.getParent().getName());
        loggerName.append("].[");
        // Host name
        loggerName.append(host.getName());
        loggerName.append("].[");
        // Context name
        if (contextName == null || contextName.isEmpty()) {
            loggerName.append('/');
        } else if (contextName.startsWith("##")) {
            loggerName.append('/');
            loggerName.append(contextName);
        }
        loggerName.append(']');

        return loggerName.toString();
    }

    /**
     * Create the configured {@link Context} for the given <code>host</code>. The default constructor of the class that
     * was configured with {@link StandardHost#setContextClass(String)} will be used
     *
     * @param host host for which the {@link Context} should be created, or <code>null</code> if default host should be
     *                 used
     * @param url  path of the webapp which should get the {@link Context}
     *
     * @return newly created {@link Context}
     */
    private Context createContext(Host host, String url) {
        String defaultContextClass = StandardContext.class.getName();
        String contextClass = StandardContext.class.getName();
        if (host == null) {
            host = this.getHost();
        }
        if (host instanceof StandardHost) {
            contextClass = ((StandardHost) host).getContextClass();
        }
        try {
            if (defaultContextClass.equals(contextClass)) {
                return new StandardContext();
            } else {
                return (Context) Class.forName(contextClass).getConstructor().newInstance();
            }

        } catch (ReflectiveOperationException | IllegalArgumentException | SecurityException e) {
            throw new IllegalArgumentException(sm.getString("tomcat.noContextClass", contextClass, host, url), e);
        }
    }

    /**
     * Enables JNDI naming which is disabled by default. Server must implement {@link Lifecycle} in order for the
     * {@link NamingContextListener} to be used.
     */
    public void enableNaming() {
        // Make sure getServer() has been called as that is where naming is
        // disabled
        getServer();
        server.addLifecycleListener(new NamingContextListener());

        System.setProperty("catalina.useNaming", "true");

        String value = "org.apache.naming";
        String oldValue = System.getProperty(javax.naming.Context.URL_PKG_PREFIXES);
        if (oldValue != null) {
            if (oldValue.contains(value)) {
                value = oldValue;
            } else {
                value = value + ":" + oldValue;
            }
        }
        System.setProperty(javax.naming.Context.URL_PKG_PREFIXES, value);

        value = System.getProperty(javax.naming.Context.INITIAL_CONTEXT_FACTORY);
        if (value == null) {
            System.setProperty(javax.naming.Context.INITIAL_CONTEXT_FACTORY,
                    "org.apache.naming.java.javaURLContextFactory");
        }
    }


    /**
     * Provide default configuration for a context. This is broadly the programmatic equivalent of the default web.xml
     * and provides the following features:
     * <ul>
     * <li>Default servlet mapped to "/"</li>
     * <li>JSP servlet mapped to "*.jsp" and ""*.jspx"</li>
     * <li>Session timeout of 30 minutes</li>
     * <li>MIME mappings (subset of those in conf/web.xml)</li>
     * <li>Welcome files</li>
     * </ul>
     *
     * @param contextPath The path of the context to set the defaults for
     */
    public void initWebappDefaults(String contextPath) {
        Container ctx = getHost().findChild(contextPath);
        initWebappDefaults((Context) ctx);
    }


    /**
     * Static version of {@link #initWebappDefaults(String)}.
     *
     * @param ctx The context to set the defaults for
     */
    public static void initWebappDefaults(Context ctx) {
        // Default servlet
        Wrapper servlet = addServlet(ctx, "default", "org.apache.catalina.servlets.DefaultServlet");
        servlet.setLoadOnStartup(1);
        servlet.setOverridable(true);

        // JSP servlet (by class name - to avoid loading all deps)
        servlet = addServlet(ctx, "jsp", "org.apache.jasper.servlet.JspServlet");
        servlet.addInitParameter("fork", "false");
        servlet.setLoadOnStartup(3);
        servlet.setOverridable(true);

        // Servlet mappings
        ctx.addServletMappingDecoded("/", "default");
        ctx.addServletMappingDecoded("*.jsp", "jsp");
        ctx.addServletMappingDecoded("*.jspx", "jsp");

        // Sessions
        ctx.setSessionTimeout(30);

        // MIME type mappings
        addDefaultMimeTypeMappings(ctx);

        // Welcome files
        ctx.addWelcomeFile("index.html");
        ctx.addWelcomeFile("index.htm");
        ctx.addWelcomeFile("index.jsp");
        // Any application configured welcome files should override the defaults.
        if (ctx instanceof StandardContext stdCtx) {
            stdCtx.setReplaceWelcomeFiles(true);
        }
    }


    /**
     * Add the default MIME type mappings to the provided Context.
     *
     * @param context The web application to which the default MIME type mappings should be added.
     */
    public static void addDefaultMimeTypeMappings(Context context) {
        Properties defaultMimeMappings = new Properties();
        try (InputStream is = Tomcat.class.getResourceAsStream("MimeTypeMappings.properties")) {
            defaultMimeMappings.load(is);
            for (Map.Entry<Object,Object> entry : defaultMimeMappings.entrySet()) {
                context.addMimeMapping((String) entry.getKey(), (String) entry.getValue());
            }
        } catch (IOException ioe) {
            throw new IllegalStateException(sm.getString("tomcat.defaultMimeTypeMappingsFail"), ioe);
        }
    }


    /**
     * Fix startup sequence - required if you don't use web.xml.
     * <p>
     * The start() method in context will set 'configured' to false - and expects a listener to set it back to true.
     */
    public static class FixContextListener implements LifecycleListener {

        @Override
        public void lifecycleEvent(LifecycleEvent event) {
            try {
                Context context = (Context) event.getLifecycle();
                if (event.getType().equals(Lifecycle.CONFIGURE_START_EVENT)) {
                    context.setConfigured(true);

                    // Process annotations
                    WebAnnotationSet.loadApplicationAnnotations(context);

                    // LoginConfig is required to process @ServletSecurity
                    // annotations
                    if (context.getLoginConfig() == null) {
                        context.setLoginConfig(new LoginConfig("NONE", null, null, null));
                        context.getPipeline().addValve(new NonLoginAuthenticator());
                    }
                }
            } catch (ClassCastException e) {
                // Ignore
            }
        }
    }


    /**
     * Fix reload - required if reloading and using programmatic configuration. When a context is reloaded, any
     * programmatic configuration is lost. This listener sets the equivalent of conf/web.xml when the context starts.
     */
    public static class DefaultWebXmlListener implements LifecycleListener {
        @Override
        public void lifecycleEvent(LifecycleEvent event) {
            if (Lifecycle.BEFORE_START_EVENT.equals(event.getType())) {
                initWebappDefaults((Context) event.getLifecycle());
            }
        }
    }


    /**
     * Helper class for wrapping existing servlets. This disables servlet lifecycle and normal reloading, but also
     * reduces overhead and provide more direct control over the servlet.
     */
    public static class ExistingStandardWrapper extends StandardWrapper {
        private final Servlet existing;

        public ExistingStandardWrapper(Servlet existing) {
            this.existing = existing;
            this.asyncSupported = hasAsync(existing);
        }

        private static boolean hasAsync(Servlet existing) {
            boolean result = false;
            Class<?> clazz = existing.getClass();
            WebServlet ws = clazz.getAnnotation(WebServlet.class);
            if (ws != null) {
                result = ws.asyncSupported();
            }
            return result;
        }

        @Override
        public synchronized Servlet loadServlet() throws ServletException {
            if (!instanceInitialized) {
                existing.init(facade);
                instanceInitialized = true;
            }
            return existing;
        }

        @Override
        public long getAvailable() {
            return 0;
        }

        @Override
        public boolean isUnavailable() {
            return false;
        }

        @Override
        public Servlet getServlet() {
            return existing;
        }

        @Override
        public String getServletClass() {
            return existing.getClass().getName();
        }
    }

    protected URL getWebappConfigFile(String path, String contextName) {
        File docBase = new File(path);
        if (docBase.isDirectory()) {
            return getWebappConfigFileFromDirectory(docBase, contextName);
        } else {
            return getWebappConfigFileFromWar(docBase, contextName);
        }
    }

    private URL getWebappConfigFileFromDirectory(File docBase, String contextName) {
        URL result = null;
        File webAppContextXml = new File(docBase, Constants.ApplicationContextXml);
        if (webAppContextXml.exists()) {
            try {
                result = webAppContextXml.toURI().toURL();
            } catch (MalformedURLException e) {
                Logger.getLogger(getLoggerName(getHost(), contextName)).log(Level.WARNING,
                        sm.getString("tomcat.noContextXml", docBase), e);
            }
        }
        return result;
    }

    private URL getWebappConfigFileFromWar(File docBase, String contextName) {
        URL result = null;
        try (JarFile jar = new JarFile(docBase)) {
            JarEntry entry = jar.getJarEntry(Constants.ApplicationContextXml);
            if (entry != null) {
                result = UriUtil.buildJarUrl(docBase, Constants.ApplicationContextXml);
            }
        } catch (IOException ioe) {
            Logger.getLogger(getLoggerName(getHost(), contextName)).log(Level.WARNING,
                    sm.getString("tomcat.noContextXml", docBase), ioe);
        }
        return result;
    }

    static {
        // Graal native images don't load any configuration except the VM default
        if (JreCompat.isGraalAvailable()) {
            try (InputStream is = new FileInputStream(
                    System.getProperty("java.util.logging.config.file", "conf/logging.properties"))) {
                LogManager.getLogManager().readConfiguration(is);
            } catch (SecurityException | IOException e) {
                // Ignore, the VM default will be used
            }
        }
    }

    /**
     * Main executable method for use with a Maven packager.
     *
     * @param args the command line arguments
     *
     * @throws Exception if an error occurs
     */
    public static void main(String[] args) throws Exception {
        // Process some command line parameters
        String[] catalinaArguments = null;
        for (int i = 0; i < args.length; i++) {
            if (args[i].equals("--no-jmx")) {
                Registry.disableRegistry();
            } else if (args[i].equals("--catalina")) {
                // This was already processed before
                // Skip the rest of the arguments as they are for Catalina
                ArrayList<String> result = new ArrayList<>(Arrays.asList(args).subList(i + 1, args.length));
                catalinaArguments = result.toArray(new String[0]);
                break;
            }
        }
        Tomcat tomcat = new Tomcat();
        // Create a Catalina instance and let it parse the configuration files
        // It will also set a shutdown hook to stop the Server when needed
        // Use the default configuration source
        tomcat.init(null, catalinaArguments);
        boolean await = false;
        String path = "";
        // Process command line parameters
        label:
        for (int i = 0; i < args.length; i++) {
            switch (args[i]) {
                case "--war":
                    if (++i >= args.length) {
                        throw new IllegalArgumentException(sm.getString("tomcat.invalidCommandLine", args[i - 1]));
                    }
                    File war = new File(args[i]);
                    tomcat.addWebapp(path, war.getAbsolutePath());
                    break;
                case "--path":
                    if (++i >= args.length) {
                        throw new IllegalArgumentException(sm.getString("tomcat.invalidCommandLine", args[i - 1]));
                    }
                    path = args[i];
                    break;
                case "--await":
                    await = true;
                    break;
                case "--no-jmx":
                    // This was already processed before
                    break;
                case "--catalina":
                    // This was already processed before
                    // Skip the rest of the arguments as they are for Catalina
                    break label;
                default:
                    throw new IllegalArgumentException(sm.getString("tomcat.invalidCommandLine", args[i]));
            }
        }
        tomcat.start();
        // Ideally the utility threads are non daemon
        if (await) {
            tomcat.getServer().await();
        }
    }

}