/**
 *
 * Copyright
 * 2009-2015 Jayway Products AB
 * 2016-2017 Föreningen Sambruk
 *
 * Licensed under AGPL, Version 3.0 (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.gnu.org/licenses/agpl.txt
 *
 * 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 se.streamsource.streamflow.web.context.administration.forms.definition;

import org.qi4j.api.injection.scope.Structure;
import org.qi4j.api.structure.Module;
import se.streamsource.dci.api.InteractionConstraint;
import se.streamsource.dci.api.InteractionConstraintDeclaration;
import se.streamsource.dci.api.RoleMap;
import se.streamsource.streamflow.web.domain.structure.form.Field;
import se.streamsource.streamflow.web.domain.structure.form.Fields;
import se.streamsource.streamflow.web.domain.structure.form.Page;
import se.streamsource.streamflow.web.domain.structure.form.Pages;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@InteractionConstraintDeclaration(FirstFieldInFirstPage.FirstFieldInFirstPageConstraint.class)
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD, ElementType.TYPE})
public @interface FirstFieldInFirstPage
{
   boolean value() default true;

   class FirstFieldInFirstPageConstraint
         implements InteractionConstraint<FirstFieldInFirstPage>
   {

      @Structure
      Module module;

      public boolean isValid( FirstFieldInFirstPage firstFieldInFirstPage, RoleMap roleMap )
      {
         try
         {
             Pages.Data pages = roleMap.get( Pages.Data.class );
             Page page = roleMap.get( Page.class );
             Fields.Data fields = roleMap.get( Fields.Data.class );
             Field field = roleMap.get( Field.class );
             if( firstFieldInFirstPage.value() && pages.pages().toList().indexOf( page ) == 0)
             {
                return ((Fields.Data)page).fields().toList().indexOf( field ) == 0;
             } else
             {
                if( pages.pages().toList().indexOf( page ) == 0 )
                   return fields.fields().toList().indexOf( field ) != 0;
                else
                   return true;
             }
         } catch ( IllegalArgumentException e )
         {
             // no pages i rolemap so we cannot be first field in first page!
             return false;
         }
      }
   }
}