/**

  * Copyright (c) 2014, stateful.co

  * All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met: 1) Redistributions of source code must retain the above

  * copyright notice, this list of conditions and the following

  * disclaimer. 2) Redistributions in binary form must reproduce the above

  * copyright notice, this list of conditions and the following

  * disclaimer in the documentation and/or other materials provided

  * with the distribution. 3) Neither the name of the stateful.co nor

  * the names of its contributors may be used to endorse or promote

  * products derived from this software without specific prior written

  * permission.

  *

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT

  * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

  * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL

  * THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,

  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

  * OF THE POSSIBILITY OF SUCH DAMAGE.

  */

 package co.stateful.core;

 import co.stateful.spi.Counters;

 import co.stateful.spi.Locks;

 import co.stateful.spi.User;

 import com.google.common.base.Joiner;

 import com.google.common.base.Splitter;

 import com.google.common.collect.Iterables;

 import com.jcabi.aspects.Cacheable;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.aspects.Loggable;

 import com.jcabi.aspects.Tv;

 import com.jcabi.dynamo.Attributes;

 import com.jcabi.dynamo.Conditions;

 import com.jcabi.dynamo.Credentials;

 import com.jcabi.dynamo.Item;

 import com.jcabi.dynamo.QueryValve;

 import com.jcabi.dynamo.Region;

 import com.jcabi.manifests.Manifests;

 import com.jcabi.urn.URN;

 import java.io.IOException;

 import java.util.Iterator;

 import java.util.Locale;

 import java.util.concurrent.TimeUnit;

 import lombok.EqualsAndHashCode;

 import lombok.ToString;

 import org.apache.commons.codec.digest.DigestUtils;

 import org.apache.commons.lang3.RandomStringUtils;

 /**

  * Default user.

  *

  * @author Yegor Bugayenko (yegor@tpc2.com)

  * @version $Id$

  * @checkstyle ClassDataAbstractionCouplingCheck (500 lines)

  */

 @Immutable

 @ToString

 @EqualsAndHashCode(of = "name")

 @Loggable(Loggable.DEBUG)

 final class DefaultUser implements User {

     /**

      * Table name.

      */

     public static final String TOKENS = "tokens";

     /**

      * Hash.

      */

     public static final String HASH = "urn";

     /**

      * Token attribute.

      */

     public static final String ATTR_TOKEN = "token";

     /**

      * Name of the user.

      */

     private final transient URN name;

     /**

      * Region.

      */

     private final transient Region region;

     /**

      * Ctor.

      * @param urn Name of it

      */

     DefaultUser(final URN urn) {

         this.name = urn;

         final String key = Manifests.read("Stateful-DynamoKey");

         Credentials creds = new Credentials.Simple(

             key,

             Manifests.read("Stateful-DynamoSecret")

         );

         if ("AAAAABBBBBAAAAABBBBB".equals(key)) {

             creds = new Credentials.Direct(

                 creds, Integer.parseInt(System.getProperty("dynamo.port"))

             );

         }

         this.region = new Region.Prefixed(

             new Region.Simple(creds),

             Manifests.read("Stateful-DynamoPrefix")

         );

     }

     @Override

     @Cacheable(forever = true)

     public boolean exists() {

         return this.region.table(DefaultUser.TOKENS)

             .frame().through(new QueryValve())

             .where(DefaultUser.HASH, Conditions.equalTo(this.name))

             .iterator().hasNext();

     }

     @Override

     @Cacheable(lifetime = 1, unit = TimeUnit.HOURS)

     public String token() throws IOException {

         final Iterator<Item> items = this.region.table(DefaultUser.TOKENS)

             .frame().through(new QueryValve())

             .where(DefaultUser.HASH, Conditions.equalTo(this.name))

             .iterator();

         final String token;

         if (items.hasNext()) {

             token = items.next().get(DefaultUser.ATTR_TOKEN).getS();

         } else {

             this.refresh();

             token = this.token();

         }

         return token;

     }

     @Override

     @Cacheable.FlushAfter

     public void refresh() throws IOException {

         this.region.table(DefaultUser.TOKENS).put(

             new Attributes()

                 .with(DefaultUser.HASH, this.name)

                 .with(

                     DefaultUser.ATTR_TOKEN,

                     Joiner.on('-').join(

                         Iterables.limit(

                             Splitter.fixedLength(Tv.FOUR).split(

                                 DigestUtils.md5Hex(

                                     RandomStringUtils.random(Tv.TEN)

                                 ).toUpperCase(Locale.ENGLISH)

                             ),

                             Tv.FOUR

                         )

                     )

                 )

         );

     }

     @Override

     @Cacheable(lifetime = 1, unit = TimeUnit.HOURS)

     public Counters counters() {

         return new DyCounters(this.region.table(DyCounters.TBL), this.name);

     }

     @Override

     public Locks locks() {

         return new DyLocks(this.region.table(DyLocks.TBL), this.name);

     }

 }