/*
 * 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.jena.propertytable.impl;

import java.io.InputStream ;
import java.util.ArrayList ;
import java.util.Iterator ;
import java.util.List ;

import org.apache.jena.atlas.csv.CSVParser ;
import org.apache.jena.atlas.io.IO ;
import org.apache.jena.datatypes.xsd.XSDDatatype ;
import org.apache.jena.graph.Node ;
import org.apache.jena.graph.NodeFactory ;
import org.apache.jena.propertytable.PropertyTable ;
import org.apache.jena.propertytable.Row ;
import org.apache.jena.propertytable.lang.LangCSV ;
import org.apache.jena.riot.system.IRIResolver ;


/**
 * A tool for constructing PropertyTable from a file (e.g., a CSV file).
 * 
 *
 */
public class PropertyTableBuilder {
	
	public static Node CSV_ROW_NODE = NodeFactory.createURI(LangCSV.CSV_ROW);
	
	public static PropertyTable buildPropetyTableHashMapImplFromCsv(String csvFilePath) {		
		PropertyTable table = new PropertyTableHashMapImpl();
		return fillPropertyTable(table, csvFilePath);
	}
	
	public static PropertyTable buildPropetyTableArrayImplFromCsv(String csvFilePath) {
		PropertyTable table = createEmptyPropertyTableArrayImpl(csvFilePath);
		return fillPropertyTable(table, csvFilePath);
	}
	
	private static PropertyTable createEmptyPropertyTableArrayImpl (String csvFilePath) {
		CSVParser parser = CSVParser.create(csvFilePath);
		List<String> rowLine = null;
		int rowNum = 0;
		int columnNum = 0;
		
		while ((rowLine = parser.parse1()) != null) {
			if (rowNum == 0) {
				columnNum = rowLine.size();
			}
			rowNum++;
		}
		if (rowNum!=0 && columnNum!=0){
			return new PropertyTableArrayImpl(rowNum, columnNum+1);
		} else {
			return null;
		}
	}

	protected static PropertyTable fillPropertyTable(PropertyTable table, String csvFilePath ){
		InputStream input = IO.openFile(csvFilePath) ;
		CSVParser iterator = CSVParser.create(input) ;
		return fillPropertyTable(table, iterator, csvFilePath);
	}
	
	protected static PropertyTable fillPropertyTable(PropertyTable table, CSVParser parser, String csvFilePath){
		if (table == null){
			return null;
		}
		ArrayList<Node> predicates = new ArrayList<Node>();
		int rowNum = 0;
		
		Iterator<List<String>> iter = parser.iterator() ;
		if ( ! iter.hasNext() )
		    return table ;
		List<String> row1 = iter.next() ;
		table.createColumn(CSV_ROW_NODE);
        for (String column : row1) {
            String uri = createColumnKeyURI(csvFilePath, column);
            Node p = NodeFactory.createURI(uri);
            predicates.add(p);
            table.createColumn(p);
        }
        
        rowNum++ ;
        while(iter.hasNext()) {
            List<String> rowLine = iter.next();
            Node subject = LangCSV.caculateSubject(rowNum, csvFilePath);
            Row row = table.createRow(subject);

            row.setValue(table.getColumn(CSV_ROW_NODE), 
                         NodeFactory.createLiteral((rowNum + ""), XSDDatatype.XSDinteger));

            for (int col = 0; col < rowLine.size() && col<predicates.size(); col++) {

                String columnValue = rowLine.get(col).trim();
                if("".equals(columnValue)){
                    continue;
                }
                Node o;
                try {
                    // Try for a double.
                    double d = Double.parseDouble(columnValue);
                    o = NodeFactory.createLiteral(columnValue,
                                                  XSDDatatype.XSDdouble);
                } catch (Exception e) {
                    o = NodeFactory.createLiteral(columnValue);
                }
                row.setValue(table.getColumn(predicates.get(col)), o);
            }
            rowNum++ ;
        }
        return table;
	}
	
	protected static String createColumnKeyURI(String csvFilePath, String column){
		String uri = IRIResolver.resolveString(csvFilePath) + "#" + LangCSV.toSafeLocalname(column);
		return uri;
	}
}