/**
    * This file Copyright (c) 2003-2011 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.module.delta;
  
  import info.magnolia.module.model.ModuleDefinition;
  import info.magnolia.module.model.Version;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Helper class to build Delta instances.
   *
   * @version $Id$
   */
  public class DeltaBuilder implements Delta {
  
      /**
       * Convenience factory method for an Update Delta with a single task.
       */
      public static DeltaBuilder update(Version toVersion, String description, Task task) {
          return update(toVersion, description).addTask(task);
      }
  
      public static DeltaBuilder update(String toVersionString, String description) {
          return update(Version.parseVersion(toVersionString), description);
      }
  
      public static DeltaBuilder update(Version toVersion, String description) {
          return new DeltaBuilder(toVersion, description, DeltaType.update);
      }
  
      public static DeltaBuilder install(Version version, String description) {
          return new DeltaBuilder(version, description, DeltaType.install);
      }
  
      public static DeltaBuilder startup(ModuleDefinition moduleDef, List<Task> tasks) {
          final String description = "Tasks executed before starting up module " + moduleDef.getDescription();
          return startup(moduleDef.getVersion(), description).addTasks(tasks);
      }
  
      public static DeltaBuilder checkPrecondition(String minimalVersion, String newVersion) {
          return update(minimalVersion, "minimal version required for updating to " + newVersion).addCondition(
                  new FalseCondition("checkPrerequisite", "Updating to " + newVersion + " is only supported from "
                          + minimalVersion + " or higher."));
      }
  
      /**
       * TODO : it seems irrelevant to have a Version in startup tasks. These should probably be moved to ModuleLifecycle.
       */
      public static DeltaBuilder startup(Version version, String description) {
          return new DeltaBuilder(version, description, DeltaType.startup);
      }
  
      private final Version version;
      private final String description;
      private final DeltaType type;
      private final List<Task> tasks;
      private final List<Condition> conditions;
  
      private DeltaBuilder(Version version, String description, DeltaType type) {
          this.version = version;
          this.description = description;
          this.type = type;
          this.tasks = new ArrayList<Task>();
          this.conditions = new ArrayList<Condition>();
      }
  
     public DeltaBuilder addTask(Task t) {
         tasks.add(t);
         return this;
     }
 
     public DeltaBuilder addTasks(List<Task> tasks) {
         this.tasks.addAll(tasks);
         return this;
     }
 
     public DeltaBuilder addCondition(Condition c) {
         conditions.add(c);
         return this;
     }
 
     public DeltaBuilder addConditions(List<Condition> conditions) {
         this.conditions.addAll(conditions);
         return this;
     }
 
     @Override
     public Version getVersion() {
         return version;
     }
 
     @Override
     public String getDescription() {
         return description;
     }
 
     @Override
     public List<Condition> getConditions() {
         return conditions;
     }
 
     @Override
     public List<Task> getTasks() {
         return tasks;
     }
 
     @Override
     public DeltaType getType() {
         return type;
     }
 
 }