/**
    * This file Copyright (c) 2012-2015 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.ui.dialog.setup;
  
  import info.magnolia.cms.util.QueryUtil;
  import info.magnolia.jcr.predicate.AbstractPredicate;
  import info.magnolia.jcr.predicate.NodeTypePredicate;
  import info.magnolia.jcr.util.NodeTypes;
  import info.magnolia.jcr.util.NodeUtil;
  import info.magnolia.jcr.util.NodeVisitor;
  import info.magnolia.jcr.util.PropertyUtil;
  import info.magnolia.module.InstallContext;
  import info.magnolia.module.delta.AbstractTask;
  import info.magnolia.module.delta.TaskExecutionException;
  import info.magnolia.objectfactory.Components;
  import info.magnolia.repository.RepositoryConstants;
  import info.magnolia.ui.dialog.setup.migration.ActionCreator;
  import info.magnolia.ui.dialog.setup.migration.BaseActionCreator;
  import info.magnolia.ui.dialog.setup.migration.ControlMigrator;
  import info.magnolia.ui.dialog.setup.migration.ControlMigratorsRegistry;
  import info.magnolia.ui.form.field.definition.StaticFieldDefinition;
  
  import java.util.Arrays;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.List;
  
  import javax.jcr.Node;
  import javax.jcr.NodeIterator;
  import javax.jcr.Property;
  import javax.jcr.RepositoryException;
  import javax.jcr.Session;
  import javax.jcr.query.Query;
  
  import org.apache.commons.lang3.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Dialog migration main task.<br>
   * Migrate all dialogs defined within the specified module.<br>
   */
  public class DialogMigrationTask extends AbstractTask {
  
      private static final Logger log = LoggerFactory.getLogger(DialogMigrationTask.class);
      private final String moduleName;
      private static final String propertyNameExtends = "extends";
      private static final String propertyNameReference = "reference";
      private final HashSet<Property> extendsAndReferenceProperty = new HashSet<Property>();
      private ControlMigratorsRegistry controlMigratorsRegistry;
  
      private HashMap<String, ControlMigrator> controlsToMigrate;
      private String defaultDialogActions = "defaultDialogActions";
      private HashMap<String, List<ActionCreator>> dialogActionsToMigrate;
      private InstallContext installContext;
  
      private HashMap<String, ControlMigrator> customControlsToMigrate;
      private HashMap<String, List<ActionCreator>> customDialogActionsToMigrate;
  
      /**
       * @param taskName
       * @param taskDescription
       * @param moduleName all dialog define under this module name will be migrated.
       * @param customControlsToMigrate Custom controls to migrate.
       * @param customDialogActionsToMigrate Custom actions to migrate
       */
      public DialogMigrationTask(String taskName, String taskDescription, String moduleName, HashMap<String, ControlMigrator> customControlsToMigrate, HashMap<String, List<ActionCreator>> customDialogActionsToMigrate) {
         super(taskName, taskDescription);
         this.moduleName = moduleName;
 
         // Use Components else we will need to inject ControlMigratorsRegistry in all version handler that uses DialogMigrationTask.
         // Version handler needs ControlMigratorsRegistry only for registrating custom dialogMigrators.
         this.controlMigratorsRegistry = Components.getComponent(ControlMigratorsRegistry.class);
         this.customControlsToMigrate = customControlsToMigrate;
         this.customDialogActionsToMigrate = customDialogActionsToMigrate;
     }
 
     public DialogMigrationTask(String taskName, String taskDescription, String moduleName) {
         this(taskName, taskDescription, moduleName, null, null);
     }
 
     public DialogMigrationTask(String moduleName) {
         this("Dialog Migration for 5.x", "Migrate dialog for the following module: " + moduleName, moduleName, null, null);
     }
 
     /**
      * Handle all Dialogs registered and migrate them.
      */
     @Override
     public void execute(InstallContext installContext) throws TaskExecutionException {
         Session session = null;
         this.installContext = installContext;
         try {
             registerControlsAndActionsMigrators();
 
             String dialogNodeName = "dialogs";
             String dialogPath = "/modules/" + moduleName + "/" + dialogNodeName;
             session = installContext.getJCRSession(RepositoryConstants.CONFIG);
 
             // Check
             if (!session.itemExists(dialogPath)) {
                 log.warn("Dialog definition do not exist for the following module {}. No Dialog migration task will be performed", moduleName);
                 return;
             }
             Node dialog = session.getNode(dialogPath);
             // Convert extends/reference path from relative to absolute.
             resolveRelativeExtendsPath(dialog);
             NodeUtil.visit(dialog, new NodeVisitor() {
                 @Override
                 public void visit(Node current) throws RepositoryException {
                     for (Node dialogNode : NodeUtil.getNodes(current, NodeTypes.ContentNode.NAME)) {
                         performDialogMigration(dialogNode);
                     }
                 }
             }, new NodeTypePredicate(NodeTypes.Content.NAME));
 
             // Try to resolve references for extends.
             postProcessForExtendsAndReference();
 
         } catch (Exception e) {
             log.error("", e);
             installContext.warn("Could not Migrate Dialog for the following module " + moduleName);
             throw new TaskExecutionException("Could not Migrate Dialog ", e);
         }
     }
 
     private void registerControlsAndActionsMigrators() {
         // Register default and passed during class initialization
         registerControlsToMigrate(customControlsToMigrate);
         registerDialogActionToCreate(customDialogActionsToMigrate);
         // Add custom
         addCustomControlsToMigrate(controlsToMigrate);
         addCustomDialogActionToCreate(dialogActionsToMigrate);
     }
 
     /**
      * Register default UI controls to migrate.
      */
     private void registerControlsToMigrate(HashMap<String, ControlMigrator> customControlsToMigrate) {
         this.controlsToMigrate = new HashMap<String, ControlMigrator>();
         // Register default controls (defined in the ui-framwork version handler class)
         this.controlsToMigrate.putAll(controlMigratorsRegistry.getAllMigrators());
         // Register custom
         if (customControlsToMigrate != null) {
             this.controlsToMigrate.putAll(customControlsToMigrate);
         }
     }
 
     /**
      * Override this method in order to register custom controls to migrate.<br>
      * In case a control name is already define in the default map, the old control migrator is replaced by the newly registered control migrator.
      *
      * @param controlsToMigrate. <br>
      * - key : controls name <br>
      * - value : {@link ControlMigrator} used to take actions in order to migrate the control into a field.
      */
     protected void addCustomControlsToMigrate(HashMap<String, ControlMigrator> controlsToMigrate) {
     }
 
     /**
      * Register default actions to create on dialogs.
      */
     private void registerDialogActionToCreate(HashMap<String, List<ActionCreator>> customDialogActionsToMigrate) {
         this.dialogActionsToMigrate = new HashMap<String, List<ActionCreator>>();
         // Register default
         // Save
         ActionCreator saveAction = new BaseActionCreator("commit", "save changes", "info.magnolia.ui.admincentral.dialog.action.SaveDialogActionDefinition");
         // Cancel
         ActionCreator cancelAction = new BaseActionCreator("cancel", "cancel", "info.magnolia.ui.admincentral.dialog.action.CancelDialogActionDefinition");
         // Create an entry
         this.dialogActionsToMigrate.put(this.defaultDialogActions, Arrays.asList(saveAction, cancelAction));
         // Register custom
         if (customDialogActionsToMigrate != null) {
             this.dialogActionsToMigrate.putAll(customDialogActionsToMigrate);
         }
     }
 
     /**
      * Override this method in order to register custom actions to create on a specific dialog.<br>
      *
      * @param dialogActionsToMigrate.<br>
      * - key: Dialog name <br>
      * - value: List of {@link ActionCreator} to create on the desired dialog.
      */
     protected void addCustomDialogActionToCreate(HashMap<String, List<ActionCreator>> dialogActionsToMigrate) {
     }
 
     /**
      * Handle and Migrate a Dialog node.
      */
     private void performDialogMigration(Node dialog) throws RepositoryException {
         // Get child Nodes (should be Tab)
         Iterable<Node> tabNodes = NodeUtil.getNodes(dialog, DIALOG_FILTER);
         if (tabNodes.iterator().hasNext()) {
             // Check if it's a tab definition
             if (dialog.hasProperty("controlType") && dialog.getProperty("controlType").getString().equals("tab")) {
                 handleTab(dialog);
             } else {
                 // Handle action
                 if (!dialog.hasProperty("controlType") && !dialog.hasProperty(propertyNameExtends) && !dialog.hasProperty(propertyNameReference)) {
                     handleAction(dialog);
                 }
                 // Handle tab
                 handleTabs(dialog, tabNodes.iterator());
             }
             // Remove class property defined on Dialog level
             if (dialog.hasProperty("class")) {
                 dialog.getProperty("class").remove();
             }
         } else {
             // Handle as a field.
             handleField(dialog);
         }
 
         handleExtendsAndReference(dialog);
     }
 
     /**
      * Add action to node.
      */
     private void handleAction(Node dialog) throws RepositoryException {
         // Create actions node
         dialog.addNode("actions", NodeTypes.ContentNode.NAME);
         Node actionsNode = dialog.getNode("actions");
 
         List<ActionCreator> actions = dialogActionsToMigrate.get(defaultDialogActions);
         //Use the specific Actions list if defined
         if (dialogActionsToMigrate.containsKey(dialog.getName())) {
             actions = dialogActionsToMigrate.get(dialog.getName());
         }
 
         for (ActionCreator action : actions) {
             action.create(actionsNode);
         }
 
     }
 
     /**
      * Handle Tabs.
      */
     private void handleTabs(Node dialog, Iterator<Node> tabNodes) throws RepositoryException {
         Node form = dialog.addNode("form", NodeTypes.ContentNode.NAME);
         handleFormLabels(dialog, form);
         Node dialogTabs = form.addNode("tabs", NodeTypes.ContentNode.NAME);
         while (tabNodes.hasNext()) {
             Node tab = tabNodes.next();
             // Handle Fields Tab
             handleTab(tab);
             // Move tab
             NodeUtil.moveNode(tab, dialogTabs);
         }
     }
 
     /**
      * Move the label property from dialog to form node.
      */
     private void handleFormLabels(Node dialog, Node form) throws RepositoryException {
         moveAndRenameLabelProperty(dialog, form, "label");
         moveAndRenameLabelProperty(dialog, form, "i18nBasename");
         moveAndRenameLabelProperty(dialog, form, "description");
     }
 
     /**
      * Move the desired property if present from the source to the target node.
      */
     private void moveAndRenameLabelProperty(Node source, Node target, String propertyName) throws RepositoryException {
         if (source.hasProperty(propertyName)) {
             Property dialogProperty = source.getProperty(propertyName);
             target.setProperty(propertyName, dialogProperty.getString());
             dialogProperty.remove();
         }
     }
 
     /**
      * Handle a Tab.
      */
     private void handleTab(Node tab) throws RepositoryException {
         if ((tab.hasProperty("controlType") && StringUtils.equals(tab.getProperty("controlType").getString(), "tab")) || (tab.getParent().hasProperty(propertyNameExtends))) {
             if (tab.hasProperty("controlType") && StringUtils.equals(tab.getProperty("controlType").getString(), "tab")) {
                 // Remove controlType Property
                 tab.getProperty("controlType").remove();
             }
             // get all controls to be migrated
             Iterator<Node> controls = NodeUtil.getNodes(tab, NodeTypes.ContentNode.NAME).iterator();
             // create a fields Node
             Node fields = tab.addNode("fields", NodeTypes.ContentNode.NAME);
 
             while (controls.hasNext()) {
                 Node control = controls.next();
                 // Handle fields
                 handleField(control);
                 // Move to fields
                 NodeUtil.moveNode(control, fields);
             }
         } else if (tab.hasNode("inheritable")) {
             // Handle inheritable
             Node inheritable = tab.getNode("inheritable");
             handleExtendsAndReference(inheritable);
         } else {
             handleExtendsAndReference(tab);
         }
     }
 
     /**
      * Change controlType to the equivalent class.
      * Change the extend path.
      */
     private void handleField(Node fieldNode) throws RepositoryException {
         if (fieldNode.hasProperty("controlType")) {
             String controlTypeName = fieldNode.getProperty("controlType").getString();
 
             if (controlsToMigrate.containsKey(controlTypeName)) {
                 ControlMigrator controlMigration = controlsToMigrate.get(controlTypeName);
                 controlMigration.migrate(fieldNode, installContext);
             } else {
                 fieldNode.setProperty("class", StaticFieldDefinition.class.getName());
                 if (!fieldNode.hasProperty("value")) {
                     fieldNode.setProperty("value", "Field not yet supported");
                 }
                 log.warn("No field defined for control '{}' for node '{}'", controlTypeName, fieldNode.getPath());
             }
         } else {
             // Handle Field Extends/Reference
             handleExtendsAndReference(fieldNode);
         }
     }
 
 
     private void handleExtendsAndReference(Node node) throws RepositoryException {
         if (node.hasProperty("extends")) {
             // Handle Field Extends
             extendsAndReferenceProperty.add(node.getProperty(propertyNameExtends));
         } else if (node.hasProperty("reference")) {
             // Handle Field Extends
             extendsAndReferenceProperty.add(node.getProperty(propertyNameReference));
         }
     }
 
     /**
      * Create a specific node filter.
      */
     private static AbstractPredicate<Node> DIALOG_FILTER = new AbstractPredicate<Node>() {
         @Override
         public boolean evaluateTyped(Node node) {
             try {
                 return !node.getName().startsWith(NodeTypes.JCR_PREFIX)
                         && !NodeUtil.isNodeType(node, NodeTypes.MetaData.NAME) &&
                         NodeUtil.isNodeType(node, NodeTypes.ContentNode.NAME);
             } catch (RepositoryException e) {
                 return false;
             }
         }
     };
 
     /**
      * Check if the extends and reference are correct. If not try to do the best
      * to found a correct path.
      */
     private void postProcessForExtendsAndReference() throws RepositoryException {
         for (Property p : extendsAndReferenceProperty) {
             String path = p.getString();
             if (path.equals("override")) {
                 continue;
             }
             if (!isAbsoulutePath(p, path)) {
                 log.warn("Reference from propertyName '{}' to '{}' is an relative path and could not be linked. The initial value will be keeped", p.getPath(), path);
                 continue;
             }
 
             if (!p.getSession().nodeExists(path)) {
 
                 String newPath = insertBeforeLastSlashAndTest(p.getSession(), path, "/tabs", "/fields", "/tabs/fields", "/form/tabs");
                 if (newPath != null) {
                     p.setValue(newPath);
                     continue;
                 }
 
                 // try to add a tabs before the 2nd last /
                 String beging = path.substring(0, path.lastIndexOf("/"));
                 String end = path.substring(beging.lastIndexOf("/"));
                 beging = beging.substring(0, beging.lastIndexOf("/"));
                 newPath = beging + "/form/tabs" + end;
                 if (p.getSession().nodeExists(newPath)) {
                     p.setValue(newPath);
                     continue;
                 }
                 // try with a fields before the last / with a tabs before the 2nd last /
                 newPath = insertBeforeLastSlash(newPath, "/fields");
                 if (p.getSession().nodeExists(newPath)) {
                     p.setValue(newPath);
                 } else {
                     log.warn("Reference from propertyName '{}' to '{}' not found. The initial value will be keeped", p.getPath(), newPath);
                 }
             }
         }
     }
 
     /**
      * @return true if the path refers to an absolute path, false otherwise.
      */
     private boolean isAbsoulutePath(Property p, String path) {
         try {
             p.getSession().nodeExists(path);
             return true;
         } catch (RepositoryException e) {
             return false;
         }
     }
 
     /**
      * Test insertBeforeLastSlash() for all toInserts.
      * If newPath exist as a node return it.
      */
     private String insertBeforeLastSlashAndTest(Session session, String reference, String... toInserts) throws RepositoryException {
         String res = null;
         for (String toInsert : toInserts) {
             String newPath = insertBeforeLastSlash(reference, toInsert);
             if (session.nodeExists(newPath)) {
                 return newPath;
             }
         }
         return res;
     }
 
     /**
      * Insert the toInsert ("/tabs") before the last /.
      */
     private String insertBeforeLastSlash(String reference, String toInsert) {
         String beging = reference.substring(0, reference.lastIndexOf("/"));
         String end = reference.substring(reference.lastIndexOf("/"));
         return beging + toInsert + end;
     }
 
     /**
      * Get All nodes defining an extends or reference property.
      * If the property value refers to a relative path, <br>
      * - try to resolve this path <br>
      * - if the equivalent absolute path is found, replace in the property value the relative path by the absolute path.
      */
     private void resolveRelativeExtendsPath(Node dialog) {
         try {
             final String queryString = "SELECT * FROM [nt:base] AS t WHERE   ISDESCENDANTNODE(t, '" + dialog.getPath() + "') AND (" + propertyNameExtends + " is not null OR " + propertyNameReference + " is not null)";
             NodeIterator iterator = QueryUtil.search(RepositoryConstants.CONFIG, queryString, Query.JCR_SQL2);
             while (iterator.hasNext()) {
                 Node node = iterator.nextNode();
                 String propertyValue = PropertyUtil.getString(node, propertyNameExtends);
                 Property property = null;
 
                 if (StringUtils.isNotBlank(propertyValue)) {
                     property = node.getProperty(propertyNameExtends);
                 } else {
                     propertyValue = PropertyUtil.getString(node, propertyNameReference);
                     property = node.getProperty(propertyNameReference);
                 }
                 // Check if it's a relative path
                 if (StringUtils.isNotBlank(propertyValue) && !isAbsoulutePath(property, propertyValue) && node.hasNode(propertyValue)) {
                     property.setValue(node.getNode(propertyValue).getPath());
                     log.info("Change propertyValue of '{}' from '{}' to '{}'", property.getPath(), propertyValue, node.getNode(propertyValue).getPath());
                 }
             }
         } catch (RepositoryException e) {
             log.warn("Could not handle extends/reference property for the following definition ", NodeUtil.getNodePathIfPossible(dialog));
         }
     }
 
 }