/*

  * Copyright 2012-2013 smartics, Kronseder & Reiner GmbH

  *

  * 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.

  */

 package de.smartics.properties.spi.config.definition;

 import java.io.Serializable;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.Map;

 import java.util.Map.Entry;

 import java.util.Set;

 import javax.annotation.CheckForNull;

 import javax.annotation.concurrent.ThreadSafe;

 import de.smartics.properties.api.config.domain.key.ConfigurationKey;

 /**

  * Contains information from the <code>definition.xml</code> that is contained

  * in archives providing property information.

  */

 @ThreadSafe

 public final class PropertiesDefinitionContext implements Serializable

 {

   // ********************************* Fields *********************************

   // --- constants ------------------------------------------------------------

   /**

    * The class version identifier.

    */

   private static final long serialVersionUID = 1L;

   /**

    * The default top level domains to identify groups.

    * <ol>

    * <li><code>biz</code></li>

    * <li><code>com</code></li>

    * <li><code>edu</code></li>

    * <li><code>gov</code></li>

    * <li><code>info</code></li>

    * <li><code>net</code></li>

    * <li><code>org</code></li>

    * </ol>

    */

   public static final Set<String> DEFAULT_TLDS;

   // --- members --------------------------------------------------------------

   /**

    * The collection of top-level-domains (tlds). Country codes (two letters) are

    * not necessarily mentioned here since they are dealt with generically.

    *

    * @serial

    */

   private final Set<String> tlds;

   /**

    * The collection of registered environment names.

    *

    * @serial

    */

   private final Set<String> environments;

   /**

    * The collection of registered node names.

    *

    * @serial

    */

   private final Set<String> nodes;

   /**

    * The collection of registered group names.

    *

    * @serial

    */

   private final Set<String> groups;

   /**

    * The mapping of properties file path names to a associated configuration

    * key.

    *

    * @serial

    */

   private final Map<String, ConfigurationKey> files;

   // ****************************** Initializer *******************************

   static

   {

     final Set<String> defaults = new HashSet<String>();

     defaults.add("biz");

     defaults.add("com");

     defaults.add("edu");

     defaults.add("gov");

     defaults.add("info");

     defaults.add("net");

     defaults.add("org");

     DEFAULT_TLDS = Collections.unmodifiableSet(defaults);

   }

   // ****************************** Constructors ******************************

   /**

    * Convenience constructor using the default TLDs and not registering any

    * environments, nodes or groups.

    */

   public PropertiesDefinitionContext()

   {

     this(DEFAULT_TLDS, null, null, null, null);

   }

   /**

    * Convenience constructor using the default TLDs and no explicit files.

    *

    * @param environments the collection of registered environment names.

    * @param nodes the collection of registered node names.

    * @param groups the collection of registered group names.

    */

   public PropertiesDefinitionContext(final Set<String> environments,

       final Set<String> nodes, final Set<String> groups)

   {

     this(DEFAULT_TLDS, environments, nodes, groups);

   }

   /**

    * Convenience constructor without an explicit path to configuration key

    * mapping.

    *

    * @param tlds the collection of top-level-domains (tlds).

    * @param environments the collection of registered environment names.

    * @param nodes the collection of registered node names.

    * @param groups the collection of registered group names.

    */

   public PropertiesDefinitionContext(final Set<String> tlds,

       final Set<String> environments, final Set<String> nodes,

       final Set<String> groups)

   {

     this(tlds, environments, nodes, groups, null);

   }

   /**

    * Convenience constructor using the default TLDs.

    *

    * @param environments the collection of registered environment names.

    * @param nodes the collection of registered node names.

    * @param groups the collection of registered group names.

    * @param files the mapping of properties file path names to a associated

    *          configuration key.

    */

   public PropertiesDefinitionContext(final Set<String> environments,

       final Set<String> nodes, final Set<String> groups,

       final Map<String, ConfigurationKey> files)

   {

     this(DEFAULT_TLDS, environments, nodes, groups, files);

   }

   /**

    * Default constructor.

    *

    * @param tlds the collection of top-level-domains (tlds).

    * @param environments the collection of registered environment names.

    * @param nodes the collection of registered node names.

    * @param groups the collection of registered group names.

    * @param files the mapping of properties file path names to a associated

    *          configuration key.

    */

   public PropertiesDefinitionContext(final Set<String> tlds,

       final Set<String> environments, final Set<String> nodes,

       final Set<String> groups, final Map<String, ConfigurationKey> files)

   {

     this.tlds = create(tlds);

     this.environments = create(environments);

     this.nodes = create(nodes);

     this.groups = create(groups);

     this.files = create(files);

   }

   // ****************************** Inner Classes *****************************

   // ********************************* Methods ********************************

   // --- init -----------------------------------------------------------------

   private static Set<String> create(final Set<String> set)

   {

     return set != null ? new HashSet<String>(set) : new HashSet<String>();

   }

   private static Map<String, ConfigurationKey> create(

       final Map<String, ConfigurationKey> map)

   {

     return map != null ? new HashMap<String, ConfigurationKey>(map)

         : new HashMap<String, ConfigurationKey>();

   }

   // --- get&set --------------------------------------------------------------

   // --- business -------------------------------------------------------------

   /**

    * Checks if the given string is a registered top level domain (tld) or

    * contains only two letters.

    *

    * @param token the token to check.

    * @return <code>true</code> if the {@code token} is not <code>null</code>, is

    *         registered or contains exactly two letters, <code>false</code>

    *         otherwise.

    */

   public boolean isRegisteredGroupTld(final String token)

   {

     return token != null && (tlds.contains(token) || isCountryTld(token));

   }

   private static boolean isCountryTld(final String tld)

   {

     return tld.length() == 2 && Character.isLetter(tld.charAt(0))

            && Character.isLetter(tld.charAt(1));

   }

   /**

    * Checks if the given token is a registered environment.

    *

    * @param token the token to check.

    * @return <code>true</code> if the token is a registered environment,

    *         <code>false</code> otherwise.

    */

   public boolean isRegisteredEnvironment(final String token)

   {

     return environments.contains(token);

   }

   /**

    * Checks if the given token is a registered node.

    *

    * @param token the token to check.

    * @return <code>true</code> if the token is a registered node,

    *         <code>false</code> otherwise.

    */

   public boolean isRegisteredNode(final String token)

   {

     return nodes.contains(token);

   }

   /**

    * Checks if the given token is a registered group.

    *

    * @param token the token to check.

    * @return <code>true</code> if the token is a registered group,

    *         <code>false</code> otherwise.

    */

   public boolean isRegisteredGroup(final String token)

   {

     return groups.contains(token);

   }

   /**

    * Returns the configuration key associated with the given {@code path}.

    *

    * @param path the path to fetch its configuration key. Note that a

    *          <code>null</code> value is allowed.

    * @return the configuration key for the given {@code path} or

    *         <code>null</code> if no key is associated with it.

    */

   @CheckForNull

   public ConfigurationKey getKey(final String path)

   {

     return files.get(path);

   }

   /**

    * Checks if the given token is a group. It is a group if it is either

    * registered explicitly or the token starts with a registered TLD or it

    * starts with two letters and a dot.

    *

    * @param token the token to check.

    * @return <code>true</code> if the token is a group, <code>false</code>

    *         otherwise.

    */

   public boolean isGroup(final String token)

   {

     if (!isRegisteredGroup(token))

     {

       final String tld = determineTld(token);

       if (isRegisteredGroupTld(tld))

       {

         return true;

       }

       return false;

     }

     return true;

   }

   private String determineTld(final String token)

   {

     final int index = token.indexOf('.');

     if (index != -1)

     {

       return token.substring(0, index);

     }

     return null;

   }

   // --- object basics --------------------------------------------------------

   @Override

   public String toString()

   {

     final StringBuilder buffer = new StringBuilder(128);

     buffer.append("TLDs          :");

     for (final String tld : tlds)

     {

       buffer.append(' ').append(tld);

     }

     buffer.append("\nEnvironments  :");

     for (final String environment : environments)

     {

       buffer.append(' ').append(environment);

     }

     buffer.append("\nNodes         :");

     for (final String node : nodes)

     {

       buffer.append(' ').append(node);

     }

     buffer.append("\nGroups        :");

     for (final String group : groups)

     {

       buffer.append(' ').append(group);

     }

     buffer.append("\nExplicit Paths:");

     for (final Entry<String, ConfigurationKey> entry : files.entrySet())

     {

       buffer.append(' ').append(entry.getKey()).append('=')

           .append(entry.getValue());

     }

     return buffer.toString();

   }

 }