/*
 * 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.tuscany.sca.domain.search.impl;

import java.util.HashMap;
import java.util.LinkedList;

import org.apache.lucene.document.Document;
import org.apache.tuscany.sca.domain.search.Result;
import org.apache.tuscany.sca.domain.search.ResultFactory;
import org.apache.tuscany.sca.domain.search.ResultProcessor;

/**
 * 
 * @version $Rev$ $Date$
 */
public class ResultProcessorList extends LinkedList<ResultProcessor> implements ResultProcessor {


    private static final long serialVersionUID = 7147307292452694895L;

    private HashMap<String, ResultHashMap> resultRoots = new HashMap<String, ResultHashMap>();

    private ResultFactory<? extends Result> resultFactory;

    public ResultProcessorList(ResultFactory<? extends Result> resultFactory) {
        this.resultFactory = resultFactory;
    }

    public Result process(Document document, Result result) {

        if (result == null) {
            result = this.resultFactory.createResult(document);

            if (result == null) {
                return null;
            }

        }

        ResultHashMap resultHashMap;

        String parent = document.get(SearchFields.PARENT_FIELD);

        if (parent == null) {
            resultHashMap = new ResultHashMap(result);
            resultRoots.put(result.getValue(), resultHashMap);

        } else {

            ParentField parentField = new ParentField(parent);
            HashMap<String, ResultHashMap> current = this.resultRoots;
            // Result currentResult = null;
            int elementsCount = parentField.getElementsCount();

            for (int i = 0; i < elementsCount; i++) {
                String actualName = parentField.getElementName(i);
                String type = parentField.getElementType(i);

                if (actualName.length() > 0) {
                    ResultHashMap actualResultHashMap = current.get(actualName);

                    if (actualResultHashMap == null) {
                        ResultHashMap aux = new ResultHashMap(type, parentField.getElementName(i));

                        current.put(aux.result.getValue(), aux);
                        // if (current.put(aux.result.getValue(), aux) == null
                        // && currentResult != null) {
                        // currentResult.addContent(aux.result);
                        // }

                        current = aux;
                        // currentResult = aux.result;

                    } else {
                        current = actualResultHashMap;
                        // currentResult = actualResultHashMap.result;

                    }

                }

            }

            resultHashMap = current.get(result.getValue());

            if (resultHashMap == null) {
                resultHashMap = new ResultHashMap(result);
                current.put(result.getValue(), resultHashMap);

                // if (currentResult != null) {
                // currentResult.addContent(result);
                // }

            }

        }

        for (ResultProcessor processor : this) {
            result = processor.process(document, result);
        }

        resultHashMap.result = result;

        return result;

    }

    private static void addContentsToResult(ResultHashMap resultHashMap) {

        for (ResultHashMap actual : resultHashMap.values()) {
            addContentsToResult(actual);

            resultHashMap.result.addContent(actual.result);

        }

    }

    public Result[] createResultRoots() {
        int size = this.resultRoots.size();

        if (size == 0) {
            return new Result[0];
        }

        Result[] res = new Result[size];

        int i = 0;
        for (ResultHashMap resultHashMap : this.resultRoots.values()) {

            addContentsToResult(resultHashMap);
            res[i++] = resultHashMap.result;

        }

        this.resultRoots.clear();

        return res;

    }

    private Result createResult(String field, String value) {
        Result result = this.resultFactory.createResult(field, value);

        if (result != null) {
            return result;
        }

        throw new IllegalArgumentException();

    }

    private class ResultHashMap extends HashMap<String, ResultHashMap> {

        private static final long serialVersionUID = 7982561264440904411L;

        Result result;

        ResultHashMap(String type, String name) {
            this(createResult(type, name));
        }

        ResultHashMap(Result result) {
            this.result = result;
        }

    }

}