/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 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.
 * Neither the name of the HISP project 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 OWNER 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 org.hisp.dhis.oust.action;

import com.opensymphony.xwork2.Action;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.hisp.dhis.organisationunit.OrganisationUnit;
import org.hisp.dhis.oust.manager.SelectionTreeManager;

/**
 * @author Torgeir Lorange Ostby
 * @version $Id: GetExpandedTreeAction.java 6260 2008-11-11 15:58:43Z larshelg $
 */
public class GetExpandedTreeAction implements Action {
  // -------------------------------------------------------------------------
  // Dependencies
  // -------------------------------------------------------------------------

  private SelectionTreeManager selectionTreeManager;

  public void setSelectionTreeManager(SelectionTreeManager selectionTreeManager) {
    this.selectionTreeManager = selectionTreeManager;
  }

  // -------------------------------------------------------------------------
  // Output
  // -------------------------------------------------------------------------

  private List<OrganisationUnit> roots;

  public List<OrganisationUnit> getRoots() {
    return roots;
  }

  private List<OrganisationUnit> parents = new ArrayList<>();

  public List<OrganisationUnit> getParents() {
    return parents;
  }

  private Map<OrganisationUnit, List<OrganisationUnit>> childrenMap = new HashMap<>();

  public Map<OrganisationUnit, List<OrganisationUnit>> getChildrenMap() {
    return childrenMap;
  }

  private Collection<OrganisationUnit> selected;

  public Collection<OrganisationUnit> getSelected() {
    return selected;
  }

  // -------------------------------------------------------------------------
  // Action implementation
  // -------------------------------------------------------------------------

  @Override
  public String execute() throws Exception {
    roots = new ArrayList<>(selectionTreeManager.getRootOrganisationUnits());

    Collections.sort(roots);

    // ---------------------------------------------------------------------
    // Get the units that need to be expanded in order for the selected
    // organisation units to be visible
    // ---------------------------------------------------------------------

    selected = selectionTreeManager.getSelectedOrganisationUnits();

    Collection<OrganisationUnit> pathNodes = findPathNodes(roots, selected);

    // ---------------------------------------------------------------------
    // Get the children of the roots
    // ---------------------------------------------------------------------

    for (OrganisationUnit root : roots) {
      if (pathNodes.contains(root)) {
        addParentWithChildren(root, pathNodes);
      }
    }

    return SUCCESS;
  }

  private void addParentWithChildren(
      OrganisationUnit parent, Collection<OrganisationUnit> pathNodes) throws Exception {
    List<OrganisationUnit> children = parent.getSortedChildren();

    parents.add(parent);

    childrenMap.put(parent, children);

    for (OrganisationUnit child : children) {
      if (pathNodes.contains(child)) {
        addParentWithChildren(child, pathNodes);
      }
    }
  }

  private final Collection<OrganisationUnit> findPathNodes(
      Collection<OrganisationUnit> roots, Collection<OrganisationUnit> selected) {
    Set<OrganisationUnit> pathNodes = new HashSet<>();

    for (OrganisationUnit unit : selected) {
      if (roots.contains(unit)) // Is parent => done
      {
        continue;
      }

      OrganisationUnit tmp = unit.getParent(); // Start with parent

      while (!roots.contains(tmp)) {
        pathNodes.add(tmp); // Add each parent

        if (tmp != null && tmp.getParent() != null) {
          tmp = tmp.getParent();
        }
      }

      pathNodes.add(tmp); // Add the root
    }

    return pathNodes;
  }
}
