/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.

 */

package com.oracle.solaris.vp.util.misc.finder;

import java.text.MessageFormat;

import java.util.*;

import com.oracle.solaris.vp.util.misc.TextUtil;

public class MessageFinder extends ItemFinder {

    //

    // Static data

    //

    /**

     * The default base name suffix ("{@code resources.Resources}") to append to

     * package names when searching for a {@code ResourceBundle}.

     */

    public static final String DEFAULT_BASE_NAME_SUFFIX = "resources.Resources";

    //

    // Instance data

    //

    // Additional paths to search for resource strings

    private List<String> addlPaths = new ArrayList<String>();

    private List<String> roAddlPaths = Collections.unmodifiableList(addlPaths);

    private String baseNameSuffix = DEFAULT_BASE_NAME_SUFFIX;

    private Locale locale;

    //

    // MessageFinder methods

    //

    /**

     * Add a base path to search for {@code ResourceBundle}s.

     *

     * @param	    path

     *		    a base path suitable for construction of a

     *		    {@code ResourceBundle}

     */

    public void addSearchPath(String path) {

	synchronized (addlPaths) {

	    if (addlPaths.indexOf(path) == -1) {

		addlPaths.add(path);

	    }

	}

    }

    /**

     * Gets the additional paths to search for {@code ResourceBundle}s.

     *

     * @return	    an unmodifiable {@code List}

     */

    public List<String> getSearchPaths() {

	return roAddlPaths;

    }

    /**

     * Get the base name suffix that is appended to package names when searching

     * for a {@code ResourceBundle}.

     */

    public String getBaseNameSuffix() {

	return baseNameSuffix;

    }

    /**

     * Gets the {@code Locale} used when retrieving {@code ResourceBundle}s.

     * The default value is the {@code Locale} returned by {@code

     * Locale.getDefault()}.

     */

    public Locale getLocale() {

	return locale == null ? Locale.getDefault() : locale;

    }

    /**

     * Return a parameterized localized string for the given key.  See the class

     * notes for details on the search algorithm.

     *

     * @param	    loader

     *		    the {@code ClassLoader} to load the resource, or {@code

     *		    null} to use the system {@code ClassLoader}

     *

     * @param	    pkg

     *		    a point in the package hierarchy to search for resources, or

     *		    {@code null} to search only from the top

     *

     * @param	    key

     *		    the identifying key in the {@code ResourceBundle}, which may

     *		    contain an optional numerical suffix (.[0-9]+) that will be

     *		    stripped off to form a backup key in case this key is not

     *		    found

     *

     * @param	    args

     *		    parameters to place into the localized string, per

     *		    the {@code java.text.MessageFormat} class.

     *

     * @return	    a parameterized localized string for the given key, or

     *		    {@code null} if no such resource is found

     */

    public String getString(ClassLoader loader, String pkg, String key,

	Object... args) {

	Locale locale = getLocale();

	String suffix = getBaseNameSuffix();

	List<String> paths = getSearchPathsFromPackage(pkg);

	paths.addAll(getSearchPaths());

	// If key ends with a numerical element, strip it off to form a backup

	// key in case this key doesn't match

	List<String> keys = new ArrayList<String>(2);

	keys.add(key);

	String altKey = key.replaceFirst("\\.\\d+$", "");

	if (!altKey.equals(key)) {

	    keys.add(altKey);

	}

	for (String path : paths) {

	    String bundleName = path.isEmpty() ? suffix : (path + "." + suffix);

	    try {

		ResourceBundle bundle = ResourceBundle.getBundle(

		    bundleName, locale, loader);

		for (String k : keys) {

		    try {

			// Throws a MissingResourceException

			String value = bundle.getString(k);

			String[] groups = TextUtil.match(value,

			    "^@forward:(((\\w+\\.)*\\w+):)?((\\w+\\.)*\\w+)");

			if (groups != null) {

			    String fPkg = groups[2] == null ? pkg : groups[2];

			    String fKey = groups[4];

			    return getString(loader, fPkg, fKey, args);

			}

			if (args != null) {

			    value = MessageFormat.format(value, args);

			}

			return value;

		    } catch (MissingResourceException ignore) {

		    }

		}

	    // Thrown by getBundle

	    } catch (MissingResourceException ignore) {

	    }

	}

	// Track down missing/bad resources during development;

	// vpanels.debug.messages is a system property containing a regular

	// expression matching all keys that should NOT be reported when no

	// message is found.

	String regex = System.getProperty("vpanels.debug.messages");

	if (regex != null && !key.matches(regex)) {

	    System.err.printf("Returning null for key: %s\n", key);

	    Thread.currentThread().dumpStack();

	}

	return null;

    }

    /**

     * Return a parameterized localized string for the given key.  See the class

     * notes for details on the search algorithm.

     *

     * @param	    pkg

     *		    a point in the package hierarchy to search for resources

     *

     * @param	    key

     *		    the identifying key in the {@code ResourceBundle}

     *

     * @param	    args

     *		    parameters to place into the localized string, per

     *		    the {@code java.text.MessageFormat} class.

     *

     * @return	    a parameterized localized string for the given key, or

     *		    {@code null} if no such resource is found

     */

    public String getStringFromPackage(String pkg, String key, Object... args) {

	return getString(getCallerClass().getClassLoader(), pkg, key, args);

    }

    /**

     * Return a parameterized localized string for the given key.  All

     * {@code ResourceBundle}s of the form {@code resources/Resources} in the

     * package hierarchy above the calling class are searched.

     *

     * @param	    key

     *		    the identifying key in the {@code ResourceBundle}

     *

     * @param	    args

     *		    parameters to place into the localized string, per

     *		    the {@code java.text.MessageFormat} class.

     *

     * @return	    a parameterized localized string for the given key, or

     *		    {@code null} if no such resource is found

     */

    public String getString(String key, Object... args) {

	Class caller = getCallerClass();

        return getString(caller.getClassLoader(), caller.getPackage().getName(),

	    key, args);

    }

    /**

     * Set the base name suffix to append to package names when searching for a

     * {@code ResourceBundle}.	The default value is identified by the {@link

     * #DEFAULT_BASE_NAME_SUFFIX DEFAULT_BASE_NAME_SUFFIX} static field.

     */

    public void setBaseNameSuffix(String baseNameSuffix) {

	this.baseNameSuffix = baseNameSuffix;

    }

    /**

     * Sets the {@code Locale} used when retrieving {@code ResourceBundle}s.

     *

     * @param	    locale

     *		    a {@code Locale} object, or {@code null} to use the

     *		    default {@code Locale}

     */

    public void setLocale(Locale locale) {

	this.locale = locale;

    }

    //

    // Private methods

    //

    private List<String> getSearchPathsFromPackage(String pkg) {

	if (pkg == null) {

	    pkg = "";

	}

	List<String> paths = new ArrayList<String>();

	while (!pkg.isEmpty()) {

	    paths.add(pkg);

	    pkg = TextUtil.getPackageName(pkg);

	}

	paths.add(pkg);

	return paths;

    }

}