/*
 * Copyright (C) 2001-2004 Red Hat Inc. All Rights Reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package com.arsdigita.themedirector;

import com.arsdigita.persistence.DataCollection;
import com.arsdigita.persistence.SessionManager;

import com.arsdigita.runtime.AbstractConfig;

import com.arsdigita.util.parameter.Parameter;
import com.arsdigita.util.parameter.StringParameter;
import com.arsdigita.util.parameter.IntegerParameter;

import java.util.Collection;
import java.util.ArrayList;
import java.util.Arrays;

import com.arsdigita.util.StringUtils;
import com.arsdigita.util.parameter.StringArrayParameter;

import javax.servlet.http.HttpServletRequest;

import org.apache.log4j.Logger;

/**
 * This is the configuration file for the Theme application
 */
public class ThemeDirectorConfig extends AbstractConfig {

    /**
     * Internal logger instance to faciliate debugging. Enable logging output by
     * editing /WEB-INF/conf/log4j.properties int the runtime environment and
     * set com.arsdigita.themedirector.ThemeDirectorConfig=DEBUG by uncommenting
     * or adding the line.
     */
    private static final Logger s_log = Logger.getLogger(
        ThemeDirectorConfig.class);

    /**
     * Singelton config object.
     */
    private static ThemeDirectorConfig s_conf;

    /**
     * Gain a ThemeDirectorConfig object.
     *
     * Singelton pattern, don't instantiate a config object using the
     * constructor directly!
     *
     * @return
     */
    public static synchronized ThemeDirectorConfig getInstance() {
        if (s_conf == null) {
            s_conf = new ThemeDirectorConfig();
            s_conf.load();
        }
        return s_conf;
    }

    // /////////////////////////////////////////////////////////////////
    // Set of Configuration Parameters
    // /////////////////////////////////////////////////////////////////
    /**
     * Directory that all of the default themes are copied from.
     */
    private final Parameter m_defaultThemePath = new StringParameter(
        "themedirector.default_theme_path",
        Parameter.OPTIONAL, "/themes/master/");

    /**
     * File containing the default themes directory. Used in conjuntion with
     * com.arsdigita.themedirectory.default_directory_filter to dictate the
     * final default directory.
     */
    private final Parameter m_defaultThemeManifest = new StringParameter(
        "themedirector.default_theme_manifest",
        Parameter.OPTIONAL, "ccm-themedirector.web.mf");

    /**
     * list of file extensions that should be included when the designer
     * requests 'all graphics files'
     */
    private final Parameter m_fileExtParam = new StringParameter(
        "themedirector.file_extensions",
        Parameter.REQUIRED,
        "bmp css eot gif jpeg jpg js less otf png svg ttf woff woff2 xml xsl");

    /**
     * Specifies the less file(s) used as entry point(s) for compiling a managed
     * theme on the fly when publishing.
     */
    private final Parameter m_lessFilesParam = new StringArrayParameter(
        "themedirector.less_files_compile",
        Parameter.OPTIONAL,
        new String[]{"styles/main.less",
                     "styles/style.less",
                     "styles/styles.less"});

    /**
     * number of seconds before checking for updated development files. in a
     * multi-jvm installation. (0 means never start)
     */
    private final Parameter m_themeDevFileWatchStartupDelay
                                = new IntegerParameter(
            "themedirector.theme_dev_file_watch_startup_delay",
            Parameter.REQUIRED, new Integer(60 * 2));

    /**
     * Number of seconds between checks for updated development files in a
     * multi-jvm installation.
     */
    private final Parameter m_themeDevFileWatchPollDelay = new IntegerParameter(
        "themedirector.theme_dev_file_watch_poll_delay",
        Parameter.REQUIRED, new Integer(60 * 90));   //once every 90 minutes

    /**
     * Number of seconds before checking for update of published theme files in
     * a multi-jvm installation. (0 means never start)
     */
    private final Parameter m_themePubFileWatchStartupDelay
                                = new IntegerParameter(
            "themedirector.theme_pub_file_watch_startup_delay",
            Parameter.REQUIRED, new Integer(60 * 2));

    /**
     * number of seconds between checks for recently published theme files in a
     * multi-jvm installation.
     */
    private final Parameter m_themePubFileWatchPollDelay = new IntegerParameter(
        "themedirector.theme_pub_file_watch_poll_delay",
        Parameter.REQUIRED, new Integer(60 * 60));  // default to once an hour

    /**
     *
     */
    private Collection m_downloadFileExtensions = null;

    /**
     * Constructor. Singelton pattern, don't instantiate a config object using
     * the constructor directly! Use getInstance() instead.
     */
    public ThemeDirectorConfig() {

        register(m_defaultThemePath);
        register(m_defaultThemeManifest);
        register(m_fileExtParam);
        register(m_lessFilesParam);

        register(m_themeDevFileWatchStartupDelay);
        register(m_themeDevFileWatchPollDelay);
        register(m_themePubFileWatchStartupDelay);
        register(m_themePubFileWatchPollDelay);

        loadInfo();
    }

    // /////////////////////////////////////////////////////////////////
    // Set of Configuration Parameters
    // /////////////////////////////////////////////////////////////////
    /**
     * Retrieves the path to a directory containing a complete set of theme
     * files to copy into a new theme as a default implementation. By default it
     * is set to a master directory containing the distribution's default theme.
     * When creating a new theme it is copied over to provide a default for the
     * new theme.
     *
     * Developer's note: Previously it was used as a string to filter a files
     * directory stored in the Manifest file. Matching files were copied to the
     * new theme's directory. The reason to use this approach is not documented.
     * As a guess: it enables to copy from more than one directory, if those
     * directories share a common name part which is specified here. But because
     * all files must be present at deploy time to be included into the Manifest
     * file it makes no sense. From original comment: "Specifically, if this is
     * not null (or the empty string) than any file that is used as part of the
     * default directory must start with this string."
     *
     * @return name of a directory containing a default theme implementation
     */
    public String getDefaultThemePath() {
        String defaultThemePath = (String) get(m_defaultThemePath);
        if (defaultThemePath == null || defaultThemePath.trim().length() == 0) {
            return null;
        }
        // remove leading slashwhich is already included in themedirector's
        // constants of the directory layout.
        if (defaultThemePath.startsWith("/")) {
            defaultThemePath = defaultThemePath.substring(1);
        }
        return defaultThemePath;
    }

    /**
     * This returns the name of the manifest file containing a list of default
     * theme.
     *
     * @return
     *
     * @deprecated replaced by a direct copy from the default directory
     */
    public String getDefaultThemeManifest() {
        return (String) get(m_defaultThemeManifest);
    }

    private static final String DEFAULT_THEME_URL = ThemeDirector.DEFAULT_THEME
                                                        + "." + Theme.URL;
    private static final String DEFAULT_THEME_URL_ATTRIBUTE
                                    = "defaultThemeURLAttribute";

    /**
     * Purpose undocumented.
     *
     * @return
     */
    public Collection getDownloadFileExtensions() {
        if (m_downloadFileExtensions == null) {
            String extensions = (String) get(m_fileExtParam);
            if (extensions != null) {
                extensions = StringUtils.stripWhiteSpace(extensions.trim());
                String[] extArray = StringUtils.split(extensions, ' ');
                m_downloadFileExtensions = Arrays.asList(extArray);
            } else {
                m_downloadFileExtensions = new ArrayList();
            }
        }
        return m_downloadFileExtensions;
    }

    /**
     * Purpose undocumented.
     *
     * @param req
     *
     * @return
     */
    public static String getDefaultThemeURL(HttpServletRequest req) {
        String themeURL = (String) req.getAttribute(DEFAULT_THEME_URL_ATTRIBUTE);
        if (null != themeURL) {
            return themeURL;
        }

        DataCollection themeApps = SessionManager.getSession().retrieve(
            ThemeDirector.BASE_DATA_OBJECT_TYPE);
        themeApps.addPath(DEFAULT_THEME_URL);

        if (themeApps.next()) {
            themeURL = (String) themeApps.get(DEFAULT_THEME_URL);

            if (s_log.isDebugEnabled()) {
                s_log.debug("Theme app: " + themeApps.get("id"));
                s_log.debug("Default Theme URL: " + themeApps.get(
                    DEFAULT_THEME_URL));
            }

            if (themeApps.next()) {
                s_log.warn(
                    "There appear to be multiple themes applications loaded");
                themeApps.close();
            }
        } else {
            s_log.warn("There doesn't appear to be a themes application loaded");
        }

        req.setAttribute(DEFAULT_THEME_URL_ATTRIBUTE, themeURL);
        return themeURL;
    }

    /**
     * The number of seconds to wait before checking the database for the first
     * time. A value of 0 means that the thread should not be started. This
     * checks for published files.
     *
     * @return
     */
    public Integer getThemePubFileWatchStartupDelay() {
        return (Integer) get(m_themePubFileWatchStartupDelay);
    }

    /**
     * Returns the number of seconds between checking for updated files in the
     * file system. This checks for published files.
     *
     * @return
     */
    public Integer getThemePubFileWatchPollDelay() {
        return (Integer) get(m_themePubFileWatchPollDelay);
    }

    /**
     * The number of seconds to wait before checking the database for the first
     * time. A value of 0 means that the thread should not be started. This
     * checks for development files.
     *
     * @return
     */
    public Integer getThemeDevFileWatchStartupDelay() {
        return (Integer) get(m_themeDevFileWatchStartupDelay);
    }

    /**
     * Returns the number of seconds between checking for updated files in the
     * file system. This checks for development files.
     *
     * @return
     */
    public Integer getThemeDevFileWatchPollDelay() {
        return (Integer) get(m_themeDevFileWatchPollDelay);
    }

    public String[] getLessFiles() {
        return (String[]) get(m_lessFilesParam);
    }

}