/**
    * Copyright 2005-2011 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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 org.kuali.rice.kim.rules.ui;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.api.util.RiceKeyConstants;
  import org.kuali.rice.kim.api.KimConstants;
  import org.kuali.rice.kim.api.permission.Permission;
  import org.kuali.rice.kim.bo.ui.KimDocumentRolePermission;
  import org.kuali.rice.kim.document.IdentityManagementRoleDocument;
  import org.kuali.rice.kim.rule.event.ui.AddPermissionEvent;
  import org.kuali.rice.kim.rule.ui.AddPermissionRule;
  import org.kuali.rice.krad.rules.DocumentRuleBase;
  import org.kuali.rice.krad.util.GlobalVariables;
  
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * This is a description of what this class does - shyu don't forget to fill this in. 
   * 
   * @author Kuali Rice Team (rice.collab@kuali.org)
   *
   */
  public class KimDocumentPermissionRule extends DocumentRuleBase implements AddPermissionRule {
  
  	public static final String ERROR_PATH = "document.permission.permissionId";
  	
  	public boolean processAddPermission(AddPermissionEvent addPermissionEvent) {
  		KimDocumentRolePermission newPermission = addPermissionEvent.getPermission();
  		if(newPermission==null || StringUtils.isEmpty(newPermission.getPermissionId())){
  			GlobalVariables.getMessageMap().putError(ERROR_PATH, RiceKeyConstants.ERROR_EMPTY_ENTRY, new String[] {"Permission"});
  			return false;
  		}
  
  		Permission kimPermissionInfo = newPermission.getPermission();
  		if(kimPermissionInfo==null){
  			GlobalVariables.getMessageMap().putError(ERROR_PATH, RiceKeyConstants.ERROR_EMPTY_ENTRY, new String[] {"Permission"});
  			return false;
  		}
  	    boolean rulePassed = true;
  		IdentityManagementRoleDocument document = (IdentityManagementRoleDocument)addPermissionEvent.getDocument();
  		if(!hasPermissionToGrantPermission(kimPermissionInfo, document)){
  	        GlobalVariables.getMessageMap().putError(KimDocumentPermissionRule.ERROR_PATH, RiceKeyConstants.ERROR_ASSIGN_PERMISSION, 
  	        		new String[] {kimPermissionInfo.getNamespaceCode(), kimPermissionInfo.getTemplate().getName()});
  	        return false;
  		}
  
  		if (newPermission == null || StringUtils.isBlank(newPermission.getPermissionId())) {
              rulePassed = false;
              GlobalVariables.getMessageMap().putError(ERROR_PATH, RiceKeyConstants.ERROR_EMPTY_ENTRY, new String[] {"Permission"});
          } else {
  		    int i = 0;
          	for (KimDocumentRolePermission permission: document.getPermissions()) {
  		    	if (permission.getPermissionId().equals(newPermission.getPermissionId())) {
  		            rulePassed = false;
  		            GlobalVariables.getMessageMap().putError("document.permissions["+i+"].permissionId", RiceKeyConstants.ERROR_DUPLICATE_ENTRY, new String[] {"Permission"});
  		    	}
  		    	i++;
  		    }
          }
  		return rulePassed;
  	} 
  
  	public boolean hasPermissionToGrantPermission(Permission kimPermissionInfo , IdentityManagementRoleDocument document){
  		Map<String,String> permissionDetails = new HashMap<String,String>();
  		permissionDetails.put(KimConstants.AttributeConstants.NAMESPACE_CODE, kimPermissionInfo.getNamespaceCode());
  		permissionDetails.put(KimConstants.AttributeConstants.PERMISSION_NAME, kimPermissionInfo.getTemplate().getName());
  		if (!getDocumentHelperService().getDocumentAuthorizer(document).isAuthorizedByTemplate(
  				document, 
  				KimConstants.NAMESPACE_CODE, 
  				KimConstants.PermissionTemplateNames.GRANT_PERMISSION,
  				GlobalVariables.getUserSession().getPerson().getPrincipalId(), 
  				permissionDetails, null)) {
  	        return false;
  		}
  		return true;
  	}
  	
  }