/*
 * Jopr Management Platform
 * Copyright (C) 2005-2008 Red Hat, Inc.
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation, and/or the GNU Lesser
 * General Public License, version 2.1, also as published by the Free
 * Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License and the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * and the GNU Lesser General Public License along with this program;
 * if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
package org.rhq.plugins.jbossas.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Properties;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jetbrains.annotations.Nullable;
import org.xml.sax.Attributes;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;

import org.rhq.core.util.StringPropertyReplacer;
import org.rhq.plugins.jbossas.helper.JBossProperties;

/**
 * This class will parse the passed File in the getConfig method. This file is normally
 * the jboss-service.xml file in the conf directory of the JBoss Server.
 *
 * Using a SaxParser it will look for the MBean tag for Naming, when it finds that it is
 * in that tag, it will then look for the Port attribute to determine the jnp port
 *
 * The JBossServerHandler class handles the searching, by determining when the SAX parser
 * has started reading the element that has the text that is being searched, and when that element
 * has ended.
 *
 * Config parsing intended only for JBoss server auto discovery.
 */
public class JnpConfig {
    private static Log log = LogFactory.getLog(JnpConfig.class);

    static final String PROPERTY_EXPRESSION_PREFIX = "${";
    private static final HashMap<File, JnpConfig> CACHE = new HashMap<File, JnpConfig>();

    private String jnpAddress;
    private Integer jnpPort;
    private long lastModified = 0;

    private String serverName;
    private File storeFile;
    private Properties systemProperties;

    private JnpConfig(Properties systemProperties) {
        this.systemProperties = systemProperties;
    }

    public static synchronized JnpConfig getConfig(final File distributionDirectory, File configXML,
        Properties systemProperties) {

        JnpConfig config = CACHE.get(configXML);

        long lastModified = configXML.lastModified();

        if ((config == null) || (lastModified != config.lastModified)) {
            config = new JnpConfig(systemProperties);
            config.lastModified = lastModified;
            CACHE.put(configXML, config);

            try {
                config.read(distributionDirectory, configXML);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        return config;
    }

    /**
     * Returns the JNP port, or null if the port could not be determined.
     *
     * @return the JNP port, or null if the port could not be determined
     */
    @Nullable
    public Integer getJnpPort() {
        return this.jnpPort;
    }

    /**
     * Returns the JNP address, or null if the address could not be determined.
     *
     * @return the JNP address, or null if the address could not be determined
     */
    @Nullable
    public String getJnpAddress() {
        return this.jnpAddress;
    }

    private void read(File distributionDirectory, File file) throws IOException {
        try {
            parseServiceXML(distributionDirectory, file);
        } catch (SAXException e) {
            throw new IllegalArgumentException(e.getMessage());
        } catch (ParserConfigurationException e) {
            throw new IllegalArgumentException(e.getMessage());
        }

        // Not in that first xml - let's try the binding service xml...
        if (this.jnpPort == null && this.storeFile != null) {
            parseBindingManagerXML();
        }
    }

    private void parseServiceXML(File distributionDirectory, File serviceXmlFile) throws IOException, SAXException,
        ParserConfigurationException {
        FileInputStream is = null;
        try {
            is = new FileInputStream(serviceXmlFile);
            SAXParserFactory factory = SAXParserFactory.newInstance();
            SAXParser parser = factory.newSAXParser();

            EntityResolver r = new LocalEntityResolver(distributionDirectory);

            JBossServiceHandler handler = new JBossServiceHandler(serviceXmlFile);

            XMLReader reader = parser.getXMLReader();

            reader.setEntityResolver(r);

            reader.setContentHandler(handler);

            reader.parse(new InputSource(is));

            this.jnpAddress = handler.getNamingBindAddress();
            this.jnpPort = handler.getNamingPort();
            this.storeFile = handler.getStoreFile();
            this.serverName = handler.getServerName();
        } finally {
            if (is != null) {
                is.close();
            }
        }
    }

    private void parseBindingManagerXML() throws IOException {
        InputStream bindIs = null;
        try {
            SAXParserFactory factory = SAXParserFactory.newInstance();
            SAXParser parser = factory.newSAXParser();

            if (!this.storeFile.isFile()) {
                log.warn("Store file does not exist: " + this.storeFile);
                return;
            }

            JBossBindingManagerHandler bindingHandler = new JBossBindingManagerHandler(this.storeFile);
            bindingHandler.setServerName(this.serverName);
            XMLReader reader = parser.getXMLReader();
            bindIs = new FileInputStream(this.storeFile);
            reader.setContentHandler(bindingHandler);
            reader.parse(new InputSource(bindIs));
            this.jnpAddress = bindingHandler.getJnpAddress();
            this.jnpPort = bindingHandler.getJnpPort();
        } catch (Exception e) {
            throw new IllegalArgumentException(e.getMessage());
        } finally {
            if (bindIs != null) {
                bindIs.close();
            }
        }
    }

    private class JBossBindingManagerHandler extends DefaultHandler {
        private File file;

        private boolean inServer = false;
        private boolean inServiceConfig = false;
        private boolean inNamingPort = false;
        private String jnpAddress;
        private Integer jnpPort;
        private String serverName;

        private JBossBindingManagerHandler(File file) {
            this.file = file;
        }

        @Override
        public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
            if (qName.equals("server")) {
                String name = attributes.getValue("name");
                if ((name != null) && name.equals(serverName)) {
                    inServer = true;
                    return;
                }
            }

            if (inServer && qName.equals("service-config")) {
                String name = attributes.getValue("name");
                if ((name != null) && name.equals("jboss:service=Naming")) {
                    inServiceConfig = true;
                    return;
                }
            }

            if (inServiceConfig && qName.equals("binding")) {
                jnpAddress = replaceProperties(attributes.getValue("host"));
                if (jnpAddress.substring(0, PROPERTY_EXPRESSION_PREFIX.length()).equals(PROPERTY_EXPRESSION_PREFIX)) {
                    log.warn("Naming binding 'host' attribute has invalid value (" + jnpAddress
                        + ") in JBossAS config file " + file
                        + " - the value should be a host name, an IP address, or a resolvable property reference.");
                    jnpAddress = null;
                }
                String jnpPortString = replaceProperties(attributes.getValue("port"));
                try {
                    jnpPort = Integer.parseInt(jnpPortString);
                } catch (NumberFormatException e) {
                    log.warn("Naming binding 'port' attribute has invalid value (" + jnpPortString
                        + ") in JBossAS config file " + file
                        + " - the value should be a positive integer or a resolvable property reference.");
                    jnpPort = null;
                }
            }

        }

        @Override
        public void endElement(String uri, String localName, String qName) {
            if (inServiceConfig && qName.equals("binding")) {
                inServiceConfig = false;
            }

            if (inNamingPort && qName.equals("service-config")) {
                inNamingPort = false;
            }

            if (inServer && qName.equals("server")) {
                inServer = false;
            }
        }

        public String getJnpAddress() {
            return this.jnpAddress;
        }

        protected Integer getJnpPort() {
            return this.jnpPort;
        }

        protected void setServerName(String serverName) {
            this.serverName = serverName;
        }
    }

    private class JBossServiceHandler extends DefaultHandler {
        private static final String DEFAULT_JNP_ADDRESS = "0.0.0.0";
        private static final String DEFAULT_JNP_PORT = "1099";

        private File file;

        //Naming Service
        private boolean inNaming = false;
        private boolean inNamingPort = false;
        private boolean inNamingBindAddress = false;
        private StringBuilder namingPort = null;
        private StringBuilder namingBindAddress = null;

        //Binding Manager
        private boolean inBinding = false;
        private boolean inServerName = false;
        private boolean inStoreURL = false;
        private boolean isBindingManagerInUse = false;
        private StringBuilder storeURL = new StringBuilder();
        private StringBuilder serverName = new StringBuilder();

        private JBossServiceHandler(File filePath) {
            this.file = filePath;
        }

        @Override
        public void characters(char[] ch, int start, int length) throws SAXException {
            if (inNamingBindAddress) {
                namingBindAddress.append(ch, start, length);
            } else if (inNamingPort) {
                namingPort.append(ch, start, length);
            } else if (inServerName) {
                serverName.append(ch, start, length);
            } else if (inStoreURL) {
                storeURL.append(ch, start, length);
            }
        }

        @Override
        public void endElement(String uri, String localName, String qName) {
            if (inNamingPort && qName.equals("attribute")) {
                inNamingPort = false;
                namingPort = processValue(namingPort, DEFAULT_JNP_PORT);
                return;
            }

            if (inNamingBindAddress && qName.equals("attribute")) {
                inNamingBindAddress = false;
                namingBindAddress = processValue(namingBindAddress, DEFAULT_JNP_ADDRESS);
                return;
            }

            if (inServerName && qName.equals("attribute")) {
                inServerName = false;
                serverName = processValue(serverName, null);
                return;
            }

            if (inStoreURL && qName.equals("attribute")) {
                storeURL = processValue(storeURL, null);
                inStoreURL = false;
                return;
            }

            if (inNaming && qName.equals("mbean")) {
                inNaming = false;
                return;
            }

            if (inBinding && qName.equals("mbean")) {
                inBinding = false;
            }
        }

        @Override
        public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
            if (inNaming && qName.equals("attribute")) {
                String name = attributes.getValue("name");
                if (name != null) {
                    if (name.equals("Port")) {
                        inNamingPort = true;
                        namingPort = new StringBuilder();
                        return;
                    } else if (name.equals("BindAddress")) {
                        inNamingBindAddress = true;
                        namingBindAddress = new StringBuilder();
                        return;
                    }
                }
            }

            if (inBinding && qName.equals("attribute")) {
                String name = attributes.getValue("name");
                if ((name != null) && name.equals("ServerName")) {
                    inServerName = true;
                    return;
                }
                if ((name != null) && name.equals("StoreURL")) {
                    inStoreURL = true;
                    return;
                }
            }

            if (qName.equals("mbean")) {
                String name = attributes.getValue("name");
                if ((name != null) && name.equals("jboss:service=Naming")) {
                    inNaming = true;
                    return;
                }
                if ((name != null) && name.equals("jboss.system:service=ServiceBindingManager")) {
                    inBinding = true;
                    isBindingManagerInUse = true;
                }
            }
        }

        protected Integer getNamingPort() {
            if (isBindingManagerInUse) {
                return null;
            }

            if (null == namingPort) {
                log.warn("Naming 'RmiPort' attribute not found in JBossAS config file " + file
                    + ". This may be ok as it can be specified in more than one place.");
                return null;
            }

            try {
                return Integer.parseInt(namingPort.toString());
            } catch (NumberFormatException e) {
                log.warn("Naming 'Port' attribute has invalid value (" + namingPort + ") in JBossAS config file "
                    + file + " - the value should be a positive integer or a resolvable property reference.");
                return null;
            }
        }

        protected String getNamingBindAddress() {
            if (isBindingManagerInUse) {
                return null;
            }

            if (null == namingBindAddress) {
                log.warn("Naming 'BindingAddress' attribute not found in JBossAS config file " + file
                    + ". This may be ok as it can be specified in more than one place.");
                return null;
            }

            String bindAddressString = namingBindAddress.toString();
            if ((null == bindAddressString) || bindAddressString.startsWith(PROPERTY_EXPRESSION_PREFIX)) {
                log.warn("Naming 'BindingAddress' attribute has invalid value (" + namingBindAddress
                    + ") in JBossAS config file " + file
                    + ". The value should be a host name, an IP address, or a resolvable property reference.");
                return null;
            }

            return bindAddressString;
        }

        protected String getServerName() {
            return serverName.toString();
        }

        protected File getStoreFile() {
            File homeDir = new File(systemProperties.getProperty(JBossProperties.HOME_DIR));
            try {
                URL url = JBossConfigurationUtility.makeURL(storeURL.toString(), homeDir);
                if (!"file".equals(url.getProtocol())) {
                    // TODO: Do we need to support non-file URL's too?
                    throw new MalformedURLException();
                }
                return new File(url.getPath());
            } catch (MalformedURLException e) {
                log.warn("Binding 'StoreURL' attribute has invalid value (" + storeURL + ") in JBossAS config file "
                    + file + " - the value should be a file URL or file path.");
                return null;
            }
        }

        private StringBuilder processValue(StringBuilder value, String defaultValue) {
            String stringValue = value.toString().trim();
            if (stringValue.equals("") && defaultValue != null) {
                stringValue = defaultValue;
            }
            stringValue = replaceProperties(stringValue);
            return new StringBuilder(stringValue);
        }
    }

    public static class LocalEntityResolver implements EntityResolver {
        static Properties resolverMap = new Properties();

        static {
            resolverMap.setProperty("-//JBoss//DTD JBOSS 3.2//EN", "jboss-service_3_2.dtd");
            resolverMap.setProperty("-//JBoss//DTD JBOSS 4.0//EN", "jboss-service_4_0.dtd");
        }

        private File distributionDirectory;

        public LocalEntityResolver(File distributionDirectory) {
            this.distributionDirectory = distributionDirectory;
        }

        public InputSource resolveEntity(String publicId, String systemId) throws SAXException, IOException {
            if (log.isDebugEnabled())
                log.debug("Resolving DTD [" + publicId + "]...");
            String dtdName = resolverMap.getProperty(publicId);
            if (dtdName != null) {
                File systemJar = new File(distributionDirectory + File.separator + "lib" + File.separator
                    + "jboss-system.jar");
                if (systemJar.exists()) {
                    JarFile j = new JarFile(systemJar);
                    try {
                        JarEntry entry = j.getJarEntry("dtd/" + dtdName);
                        if (entry == null) {
                            entry = j.getJarEntry("org/jboss/metadata/" + dtdName);
                        }

                        if (entry != null) {
                            if (log.isDebugEnabled())
                                log.debug("Found DTD locally: " + entry.getName());

                            return new InputSource(j.getInputStream(entry));
                        }
                    } finally {
                        j.close();
                    }
                }
            }

            return null;
        }
    }

    private String replaceProperties(String value) {
        return (value != null) ? StringPropertyReplacer.replaceProperties(value, this.systemProperties) : null;
    }

    public static void main(String[] args) throws Exception {
        if (args.length != 1) {
            System.err.println("Usage: <config file>");
            System.exit(1);
        }

        File serviceFile = new File(args[0]);
        File distDir = serviceFile.getParentFile().getParentFile().getParentFile().getParentFile();

        // Pass in an empty set of System properties.
        JnpConfig cfg = JnpConfig.getConfig(distDir, serviceFile, new Properties());

        System.out.println("JNP address: " + cfg.getJnpAddress());
        System.out.println("JNP port: " + cfg.getJnpPort());
    }
}