/*
 * 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.rya.indexing.mongodb.geo;

import java.util.Map;
import java.util.Set;

import org.apache.hadoop.conf.Configuration;
import org.apache.rya.indexing.GeoConstants;
import org.apache.rya.indexing.GeoIndexer;
import org.apache.rya.indexing.IndexingExpr;
import org.apache.rya.indexing.IteratorFactory;
import org.apache.rya.indexing.SearchFunction;
import org.apache.rya.indexing.StatementConstraints;
import org.apache.rya.indexing.accumulo.geo.GeoTupleSet;
import org.apache.rya.indexing.external.tupleSet.ExternalTupleSet;
import org.eclipse.rdf4j.common.iteration.CloseableIteration;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Statement;
import org.eclipse.rdf4j.model.Value;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryEvaluationException;

import com.google.common.base.Joiner;
import com.google.common.collect.Maps;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.io.ParseException;
import com.vividsolutions.jts.io.WKTReader;

public class MongoGeoTupleSet extends ExternalTupleSet {

    private Configuration conf;
    private GeoIndexer geoIndexer;
    private IndexingExpr filterInfo;
   

    public MongoGeoTupleSet(IndexingExpr filterInfo, GeoIndexer geoIndexer) {
        this.filterInfo = filterInfo;
        this.geoIndexer = geoIndexer;
        this.conf = geoIndexer.getConf();
    }

    @Override
    public Set<String> getBindingNames() {
        return filterInfo.getBindingNames();
    }

    public GeoTupleSet clone() {
        return new GeoTupleSet(filterInfo, geoIndexer);
    }

    @Override
    public double cardinality() {
        return 0.0; // No idea how the estimate cardinality here.
    }
    
   
    @Override
    public String getSignature() {
        return "(GeoTuple Projection) " + "variables: " + Joiner.on(", ").join(this.getBindingNames()).replaceAll("\\s+", " ");
    }
    
    
    @Override
    public boolean equals(Object other) {
        if (other == this) {
            return true;
        }
        if (!(other instanceof MongoGeoTupleSet)) {
            return false;
        }
        MongoGeoTupleSet arg = (MongoGeoTupleSet) other;
        return this.filterInfo.equals(arg.filterInfo);
    }
    
    @Override
    public int hashCode() {
        int result = 17;
        result = 31*result + filterInfo.hashCode();
        
        return result;
    }
    
    
    /**
     * Returns an iterator over the result set of the contained IndexingExpr.
     * <p>
     * Should be thread-safe (concurrent invocation {@link OfflineIterable} this
     * method can be expected with some query evaluators.
     */
    @Override
    public CloseableIteration<BindingSet, QueryEvaluationException> evaluate(BindingSet bindings)
            throws QueryEvaluationException {
        
      
        IRI funcURI = filterInfo.getFunction();
        SearchFunction searchFunction = (new MongoGeoSearchFunctionFactory(conf)).getSearchFunction(funcURI);
        if(filterInfo.getArguments().length > 1) {
            throw new IllegalArgumentException("Index functions do not support more than two arguments.");
        }

        String queryText = ((Value) filterInfo.getArguments()[0]).stringValue();
        
        return IteratorFactory.getIterator(filterInfo.getSpConstraint(), bindings, queryText, searchFunction);
    }


    //returns appropriate search function for a given URI
    //search functions used in GeoMesaGeoIndexer to access index
    public class MongoGeoSearchFunctionFactory {
        
        Configuration conf;
        
        private final Map<IRI, SearchFunction> SEARCH_FUNCTION_MAP = Maps.newHashMap();

        public MongoGeoSearchFunctionFactory(Configuration conf) {
            this.conf = conf;
        }
        

        /**
         * Get a {@link GeoSearchFunction} for a given URI.
         * 
         * @param searchFunction
         * @return
         */
        public SearchFunction getSearchFunction(final IRI searchFunction) {

            SearchFunction geoFunc = null;

            try {
                geoFunc = getSearchFunctionInternal(searchFunction);
            } catch (QueryEvaluationException e) {
                e.printStackTrace();
            }

            return geoFunc;
        }

        private SearchFunction getSearchFunctionInternal(final IRI searchFunction) throws QueryEvaluationException {
            SearchFunction sf = SEARCH_FUNCTION_MAP.get(searchFunction);

            if (sf != null) {
                return sf;
            } else {
                throw new QueryEvaluationException("Unknown Search Function: " + searchFunction.stringValue());
            }
        }

        private final SearchFunction GEO_EQUALS = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_EQUALS";
            };
        };

        private final SearchFunction GEO_DISJOINT = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_DISJOINT";
            };
        };

        private final SearchFunction GEO_INTERSECTS = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_INTERSECTS";
            };
        };

        private final SearchFunction GEO_TOUCHES = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_TOUCHES";
            };
        };

        private final SearchFunction GEO_CONTAINS = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_CONTAINS";
            };
        };

        private final SearchFunction GEO_OVERLAPS = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_OVERLAPS";
            };
        };

        private final SearchFunction GEO_CROSSES = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_CROSSES";
            };
        };

        private final SearchFunction GEO_WITHIN = new SearchFunction() {

            @Override
            public CloseableIteration<Statement, QueryEvaluationException> performSearch(String queryText,
                    StatementConstraints contraints) throws QueryEvaluationException {
                try {
                    WKTReader reader = new WKTReader();
                    Geometry geometry = reader.read(queryText);
                    CloseableIteration<Statement, QueryEvaluationException> statements = geoIndexer.queryWithin(
                            geometry, contraints);
                    return statements;
                } catch (ParseException e) {
                    throw new QueryEvaluationException(e);
                }
            }

            @Override
            public String toString() {
                return "GEO_WITHIN";
            };
        };

        {
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_EQUALS, GEO_EQUALS);
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_DISJOINT, GEO_DISJOINT);
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_INTERSECTS, GEO_INTERSECTS);
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_TOUCHES, GEO_TOUCHES);
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_CONTAINS, GEO_CONTAINS);
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_OVERLAPS, GEO_OVERLAPS);
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_CROSSES, GEO_CROSSES);
            SEARCH_FUNCTION_MAP.put(GeoConstants.GEO_SF_WITHIN, GEO_WITHIN);
        }

    }

}