/*
 * (C) Copyright 2010-2015 Nuxeo SA (http://nuxeo.com/) and others.
 *
 * 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.
 *
 * Contributors:
 *     Julien Carsique
 *
 */

package org.nuxeo.launcher.config;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.FilenameFilter;
import java.io.IOException;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.log4j.BasicConfigurator;
import org.apache.log4j.xml.DOMConfigurator;

import org.nuxeo.common.codec.CryptoProperties;
import org.nuxeo.common.utils.TextTemplate;

import freemarker.template.TemplateException;

/**
 * @author jcarsique
 */
public abstract class ServerConfigurator {

    protected static final Log log = LogFactory.getLog(ServerConfigurator.class);

    protected final ConfigurationGenerator generator;

    protected File dataDir = null;

    protected File logDir = null;

    protected File pidDir = null;

    protected File libDir = null;

    protected File tmpDir = null;

    protected File packagesDir = null;

    /**
     * @since 5.4.2
     */
    public static final List<String> NUXEO_SYSTEM_PROPERTIES = Arrays.asList(new String[] { "nuxeo.conf", "nuxeo.home",
            "log.id" });

    protected static final String DEFAULT_CONTEXT_NAME = "/nuxeo";

    private static final String NEW_FILES = ConfigurationGenerator.TEMPLATES + File.separator + "files.list";

    /**
     * @since 5.4.2
     * @deprecated Since 5.9.4. Use {@link org.nuxeo.common.Environment#DEFAULT_LOG_DIR} instead.
     */
    @Deprecated
    public static final String DEFAULT_LOG_DIR = org.nuxeo.common.Environment.DEFAULT_LOG_DIR;

    /**
     * @deprecated Since 5.9.4. Use {@link org.nuxeo.common.Environment#DEFAULT_DATA_DIR} instead.
     */
    @Deprecated
    public static final String DEFAULT_DATA_DIR = org.nuxeo.common.Environment.DEFAULT_DATA_DIR;

    /**
     * @since 5.4.2
     * @deprecated Since 5.9.4. Use {@link org.nuxeo.common.Environment#DEFAULT_TMP_DIR} instead.
     */
    @Deprecated
    public static final String DEFAULT_TMP_DIR = org.nuxeo.common.Environment.DEFAULT_TMP_DIR;

    public ServerConfigurator(ConfigurationGenerator configurationGenerator) {
        generator = configurationGenerator;
    }

    /**
     * @return true if server configuration files already exist
     */
    abstract boolean isConfigured();

    /**
     * Generate configuration files from templates and given configuration parameters
     *
     * @param config Properties with configuration parameters for template replacement
     * @throws ConfigurationException
     */
    protected void parseAndCopy(Properties config) throws IOException, TemplateException, ConfigurationException {
        // FilenameFilter for excluding "nuxeo.defaults" files from copy
        final FilenameFilter filter = new FilenameFilter() {
            @Override
            public boolean accept(File dir, String name) {
                return !ConfigurationGenerator.NUXEO_DEFAULT_CONF.equals(name);
            }
        };
        final TextTemplate templateParser = new TextTemplate(config);
        templateParser.setKeepEncryptedAsVar(true);
        templateParser.setTrim(true);
        templateParser.setTextParsingExtensions(config.getProperty(
                ConfigurationGenerator.PARAM_TEMPLATES_PARSING_EXTENSIONS, "xml,properties,nx"));
        templateParser.setFreemarkerParsingExtensions(config.getProperty(
                ConfigurationGenerator.PARAM_TEMPLATES_FREEMARKER_EXTENSIONS, "nxftl"));

        deleteTemplateFiles();
        // add included templates directories
        List<String> newFilesList = new ArrayList<>();
        for (File includedTemplate : generator.getIncludedTemplates()) {
            File[] listFiles = includedTemplate.listFiles(filter);
            if (listFiles != null) {
                String templateName = includedTemplate.getName();
                log.debug(String.format("Parsing %s... %s", templateName, Arrays.toString(listFiles)));
                // Check for deprecation
                Boolean isDeprecated = Boolean.valueOf(config.getProperty(templateName + ".deprecated"));
                if (isDeprecated) {
                    log.warn("WARNING: Template " + templateName + " is deprecated.");
                    String deprecationMessage = config.getProperty(templateName + ".deprecation");
                    if (deprecationMessage != null) {
                        log.warn(deprecationMessage);
                    }
                }
                // Retrieve optional target directory if defined
                String outputDirectoryStr = config.getProperty(templateName + ".target");
                File outputDirectory = (outputDirectoryStr != null) ? new File(generator.getNuxeoHome(),
                        outputDirectoryStr) : getOutputDirectory();
                for (File in : listFiles) {
                    // copy template(s) directories parsing properties
                    newFilesList.addAll(templateParser.processDirectory(in, new File(outputDirectory, in.getName())));
                }
            }
        }
        storeNewFilesList(newFilesList);
    }

    /**
     * Delete files previously deployed by templates. If a file had been overwritten by a template, it will be restored.
     * Helps the server returning to the state before any template was applied.
     *
     * @throws IOException
     * @throws ConfigurationException
     */
    private void deleteTemplateFiles() throws IOException, ConfigurationException {
        File newFiles = new File(generator.getNuxeoHome(), NEW_FILES);
        if (!newFiles.exists()) {
            return;
        }
        BufferedReader reader = null;
        try {
            reader = new BufferedReader(new FileReader(newFiles));
            String line;
            while ((line = reader.readLine()) != null) {
                if (line.endsWith(".bak")) {
                    log.debug("Restore " + line);
                    try {
                        File backup = new File(generator.getNuxeoHome(), line);
                        File original = new File(generator.getNuxeoHome(), line.substring(0, line.length() - 4));
                        FileUtils.copyFile(backup, original);
                        backup.delete();
                    } catch (IOException e) {
                        throw new ConfigurationException(String.format("Failed to restore %s from %s\nEdit or "
                                + "delete %s to bypass that error.", line.substring(0, line.length() - 4), line,
                                newFiles), e);
                    }
                } else {
                    log.debug("Remove " + line);
                    new File(generator.getNuxeoHome(), line).delete();
                }
            }
        } finally {
            IOUtils.closeQuietly(reader);
        }
        newFiles.delete();
    }

    /**
     * Store into {@link #NEW_FILES} the list of new files deployed by the templates. For later use by
     * {@link #deleteTemplateFiles()}
     *
     * @param newFilesList
     * @throws IOException
     */
    private void storeNewFilesList(List<String> newFilesList) throws IOException {
        BufferedWriter writer = null;
        try {
            // Store new files listing
            File newFiles = new File(generator.getNuxeoHome(), NEW_FILES);
            writer = new BufferedWriter(new FileWriter(newFiles, false));
            int index = generator.getNuxeoHome().getCanonicalPath().length() + 1;
            for (String filepath : newFilesList) {
                writer.write(new File(filepath).getCanonicalPath().substring(index));
                writer.newLine();
            }
        } finally {
            IOUtils.closeQuietly(writer);
        }
    }

    /**
     * @return output directory for files generation
     */
    protected File getOutputDirectory() {
        return getRuntimeHome();
    }

    /**
     * @return Default data directory path relative to Nuxeo Home
     * @since 5.4.2
     */
    protected String getDefaultDataDir() {
        return org.nuxeo.common.Environment.DEFAULT_DATA_DIR;
    }

    /**
     * Returns the Home of NuxeoRuntime (same as Framework.getRuntime().getHome().getAbsolutePath())
     */
    protected abstract File getRuntimeHome();

    /**
     * @return Data directory
     * @since 5.4.2
     */
    public File getDataDir() {
        if (dataDir == null) {
            dataDir = new File(generator.getNuxeoHome(), getDefaultDataDir());
        }
        return dataDir;
    }

    /**
     * @return Log directory
     * @since 5.4.2
     */
    public File getLogDir() {
        if (logDir == null) {
            logDir = new File(generator.getNuxeoHome(), org.nuxeo.common.Environment.DEFAULT_LOG_DIR);
        }
        return logDir;
    }

    /**
     * @param dataDirStr Data directory path to set
     * @since 5.4.2
     */
    public void setDataDir(String dataDirStr) {
        dataDir = new File(dataDirStr);
        dataDir.mkdirs();
    }

    /**
     * @param logDirStr Log directory path to set
     * @since 5.4.2
     */
    public void setLogDir(String logDirStr) {
        logDir = new File(logDirStr);
        logDir.mkdirs();
    }

    /**
     * Initialize logs. This is called before {@link ConfigurationGenerator#init()} so the {@code logDir} field is not
     * yet initialized
     *
     * @since 5.4.2
     */
    public void initLogs() {
        File logFile = getLogConfFile();
        try {
            String logDirectory = System.getProperty(org.nuxeo.common.Environment.NUXEO_LOG_DIR);
            if (logDirectory == null) {
                System.setProperty(org.nuxeo.common.Environment.NUXEO_LOG_DIR, getLogDir().getPath());
            }
            if (logFile == null || !logFile.exists()) {
                System.out.println("No logs configuration, will setup a basic one.");
                BasicConfigurator.configure();
            } else {
                System.out.println("Try to configure logs with " + logFile);
                DOMConfigurator.configure(logFile.toURI().toURL());
            }
            log.info("Logs successfully configured.");
        } catch (MalformedURLException e) {
            log.error("Could not initialize logs with " + logFile, e);
        }
    }

    /**
     * @return Pid directory (usually known as "run directory"); Returns log directory if not set by configuration.
     * @since 5.4.2
     */
    public File getPidDir() {
        if (pidDir == null) {
            pidDir = getLogDir();
        }
        return pidDir;
    }

    /**
     * @param pidDirStr Pid directory path to set
     * @since 5.4.2
     */
    public void setPidDir(String pidDirStr) {
        pidDir = new File(pidDirStr);
        pidDir.mkdirs();
    }

    /**
     * Check server paths; warn if existing deprecated paths. Override this method to perform server specific checks.
     *
     * @throws ConfigurationException If deprecated paths have been detected
     * @since 5.4.2
     */
    public void checkPaths() throws ConfigurationException {
        File badInstanceClid = new File(generator.getNuxeoHome(), getDefaultDataDir() + File.separator
                + "instance.clid");
        if (badInstanceClid.exists() && !getDataDir().equals(badInstanceClid.getParentFile())) {
            log.warn(String.format("Moving %s to %s.", badInstanceClid, getDataDir()));
            try {
                FileUtils.moveFileToDirectory(badInstanceClid, getDataDir(), true);
            } catch (IOException e) {
                throw new ConfigurationException("NXP-6722 move failed: " + e.getMessage(), e);
            }
        }

        File oldPackagesPath = new File(getDataDir(), getDefaultPackagesDir());
        if (oldPackagesPath.exists() && !oldPackagesPath.equals(getPackagesDir())) {
            log.warn(String.format(
                    "NXP-8014 Packages cache location changed. You can safely delete %s or move its content to %s",
                    oldPackagesPath, getPackagesDir()));
        }

    }

    /**
     * @return Temporary directory
     * @since 5.4.2
     */
    public File getTmpDir() {
        if (tmpDir == null) {
            tmpDir = new File(generator.getNuxeoHome(), getDefaultTmpDir());
        }
        return tmpDir;
    }

    /**
     * @return Default temporary directory path relative to Nuxeo Home
     * @since 5.4.2
     */
    public String getDefaultTmpDir() {
        return org.nuxeo.common.Environment.DEFAULT_TMP_DIR;
    }

    /**
     * @param tmpDirStr Temporary directory path to set
     * @since 5.4.2
     */
    public void setTmpDir(String tmpDirStr) {
        tmpDir = new File(tmpDirStr);
        tmpDir.mkdirs();
    }

    /**
     * @see Environment
     * @param key directory system key
     * @param directory absolute or relative directory path
     * @since 5.4.2
     */
    public void setDirectory(String key, String directory) {
        String absoluteDirectory = setAbsolutePath(key, directory);
        if (org.nuxeo.common.Environment.NUXEO_DATA_DIR.equals(key)) {
            setDataDir(absoluteDirectory);
        } else if (org.nuxeo.common.Environment.NUXEO_LOG_DIR.equals(key)) {
            setLogDir(absoluteDirectory);
        } else if (org.nuxeo.common.Environment.NUXEO_PID_DIR.equals(key)) {
            setPidDir(absoluteDirectory);
        } else if (org.nuxeo.common.Environment.NUXEO_TMP_DIR.equals(key)) {
            setTmpDir(absoluteDirectory);
        } else if (org.nuxeo.common.Environment.NUXEO_MP_DIR.equals(key)) {
            setPackagesDir(absoluteDirectory);
        } else {
            log.error("Unknown directory key: " + key);
        }
    }

    /**
     * @param absoluteDirectory
     * @since 5.9.4
     */
    private void setPackagesDir(String packagesDirStr) {
        packagesDir = new File(packagesDirStr);
        packagesDir.mkdirs();
    }

    /**
     * Make absolute the directory passed in parameter. If it was relative, then store absolute path in user config
     * instead of relative and return value
     *
     * @param key Directory system key
     * @param directory absolute or relative directory path
     * @return absolute directory path
     * @since 5.4.2
     */
    private String setAbsolutePath(String key, String directory) {
        if (!new File(directory).isAbsolute()) {
            directory = new File(generator.getNuxeoHome(), directory).getPath();
            generator.getUserConfig().setProperty(key, directory);
        }
        return directory;
    }

    /**
     * @see Environment
     * @param key directory system key
     * @return Directory denoted by key
     * @since 5.4.2
     */
    public File getDirectory(String key) {
        if (org.nuxeo.common.Environment.NUXEO_DATA_DIR.equals(key)) {
            return getDataDir();
        } else if (org.nuxeo.common.Environment.NUXEO_LOG_DIR.equals(key)) {
            return getLogDir();
        } else if (org.nuxeo.common.Environment.NUXEO_PID_DIR.equals(key)) {
            return getPidDir();
        } else if (org.nuxeo.common.Environment.NUXEO_TMP_DIR.equals(key)) {
            return getTmpDir();
        } else if (org.nuxeo.common.Environment.NUXEO_MP_DIR.equals(key)) {
            return getPackagesDir();
        } else {
            log.error("Unknown directory key: " + key);
            return null;
        }
    }

    /**
     * Check if oldPath exist; if so, then raise a ConfigurationException with information for fixing issue
     *
     * @param oldPath Path that must NOT exist
     * @param message Error message thrown with exception
     * @throws ConfigurationException If an old path has been discovered
     */
    protected void checkPath(File oldPath, String message) throws ConfigurationException {
        if (oldPath.exists()) {
            log.error("Deprecated paths used.");
            throw new ConfigurationException(message);
        }
    }

    /**
     * @return Log4J configuration file
     * @since 5.4.2
     */
    public abstract File getLogConfFile();

    /**
     * @return Nuxeo config directory
     * @since 5.4.2
     */
    public abstract File getConfigDir();

    /**
     * @since 5.4.2
     */
    public void prepareWizardStart() {
        // Nothing to do by default
    }

    /**
     * @since 5.4.2
     */
    public void cleanupPostWizard() {
        // Nothing to do by default
    }

    /**
     * Override it to make the wizard available for a given server.
     *
     * @return true if configuration wizard is required before starting Nuxeo
     * @since 5.4.2
     * @see #prepareWizardStart()
     * @see #cleanupPostWizard()
     */
    public boolean isWizardAvailable() {
        return false;
    }

    /**
     * @param userConfig Properties to dump into config directory
     * @since 5.4.2
     */
    public void dumpProperties(CryptoProperties userConfig) {
        Properties dumpedProperties = filterSystemProperties(userConfig);
        File dumpedFile = generator.getDumpedConfig();
        OutputStream os = null;
        try {
            os = new FileOutputStream(dumpedFile, false);
            dumpedProperties.store(os, "Generated by " + getClass());
        } catch (FileNotFoundException e) {
            log.error(e);
        } catch (IOException e) {
            log.error("Could not dump properties to " + dumpedFile, e);
        } finally {
            IOUtils.closeQuietly(os);
        }
    }

    /**
     * Extract Nuxeo properties from given Properties (System properties are removed, except those set by Nuxeo)
     *
     * @param properties Properties to be filtered
     * @return copy of given properties filtered out of System properties
     * @since 5.4.2
     */
    public Properties filterSystemProperties(CryptoProperties properties) {
        Properties dumpedProperties = new Properties();
        for (@SuppressWarnings("unchecked")
        Enumeration<String> propertyNames = (Enumeration<String>) properties.propertyNames(); propertyNames.hasMoreElements();) {
            String key = propertyNames.nextElement();
            // Exclude System properties except Nuxeo's System properties
            if (!System.getProperties().containsKey(key) || NUXEO_SYSTEM_PROPERTIES.contains(key)) {
                dumpedProperties.setProperty(key, properties.getRawProperty(key));
            }
        }
        return dumpedProperties;
    }

    /**
     * @return Nuxeo's third party libraries directory
     * @since 5.4.1
     */
    public File getNuxeoLibDir() {
        return new File(getRuntimeHome(), "lib");
    }

    /**
     * @return Server's third party libraries directory
     * @since 5.4.1
     */
    public abstract File getServerLibDir();

    /**
     * @throws ConfigurationException
     * @since 5.7
     */
    public void verifyInstallation() throws ConfigurationException {
        checkPaths();
        checkNetwork();
    }

    /**
     * Perform server specific checks, not already done by {@link ConfigurationGenerator#checkAddressesAndPorts()}
     *
     * @throws ConfigurationException
     * @since 5.7
     * @see ConfigurationGenerator#checkAddressesAndPorts()
     */
    protected void checkNetwork() throws ConfigurationException {
    }

    /**
     * Override to add server specific parameters to the list of parameters to migrate
     *
     * @param parametersmigration
     * @since 5.7
     */
    protected void addServerSpecificParameters(Map<String, String> parametersmigration) {
        // Nothing to do
    }

    /**
     * @return Marketplace Packages directory
     * @since 5.9.4
     */
    public File getPackagesDir() {
        if (packagesDir == null) {
            packagesDir = new File(generator.getNuxeoHome(), getDefaultPackagesDir());
        }
        return packagesDir;
    }

    /**
     * @return Default MP directory path relative to Nuxeo Home
     * @since 5.9.4
     */
    public String getDefaultPackagesDir() {
        return org.nuxeo.common.Environment.DEFAULT_MP_DIR;
    }

}