/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache 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.apache.org/licenses/LICENSE-2.0
 * 
 * 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.apache.uima.ruta.condition;

import java.util.List;

import org.apache.uima.cas.FSIterator;
import org.apache.uima.cas.Type;
import org.apache.uima.cas.text.AnnotationFS;
import org.apache.uima.ruta.RutaStream;
import org.apache.uima.ruta.expression.type.AbstractTypeListExpression;
import org.apache.uima.ruta.expression.type.ITypeExpression;
import org.apache.uima.ruta.rule.EvaluatedCondition;
import org.apache.uima.ruta.rule.MatchContext;
import org.apache.uima.ruta.visitor.InferenceCrowd;

public class BeforeCondition extends TypeSentiveCondition {

  public BeforeCondition(ITypeExpression type) {
    super(type);
  }

  public BeforeCondition(AbstractTypeListExpression list) {
    super(list);
  }

  @Override
  public EvaluatedCondition eval(MatchContext context, RutaStream stream, InferenceCrowd crowd) {
    AnnotationFS annotation = context.getAnnotation();
    if (!isWorkingOnList()) {
      Type t = type.getType(context, stream);
      boolean result = check(annotation, stream, t);
      return new EvaluatedCondition(this, result);
    } else {
      boolean result = false;
      List<Type> types = getList().getList(context, stream);
      for (Type t : types) {
        result |= check(annotation, stream, t);
        if (result == true) {
          break;
        }
      }
      return new EvaluatedCondition(this, result);
    }
  }

  private boolean check(AnnotationFS annotation, RutaStream stream, Type t) {
    if (annotation == null || t == null) {
      return false;
    }

    AnnotationFS window = stream.getDocumentAnnotation();

    FSIterator<AnnotationFS> it = null;
    if (window == null || window.equals(stream.getCas().getDocumentAnnotation())) {
      it = stream.getCas().getAnnotationIndex(t).iterator();
    } else {
      it = stream.getCas().getAnnotationIndex(t).subiterator(window);
    }

    it.moveToLast();

    if (it.isValid()) {
      AnnotationFS last = it.get();
      if (last.getBegin() >= annotation.getEnd()) {
        return true;
      }
    }

    return false;
  }

}
