/*
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.edgent.samples.connectors.jdbc;

import java.io.BufferedReader;
import java.io.File;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.util.stream.Collectors;

/**
 * Utilities for loading the sample's person data.
 */
public class PersonData {
    
    /**
     * Load the person data from the path specified by the "persondata.path"
     * property.
     * @param props configuration properties
     * @return the loaded person data
     * @throws Exception on failure
     */
    public static List<Person> loadPersonData(Properties props) throws Exception {
        String pathname = props.getProperty("persondata.path");
        List<Person> persons = new ArrayList<>();
        Path path = new File(pathname).toPath();
        try (BufferedReader br = Files.newBufferedReader(path)) {
            int lineno = 0;
            String line;
            while ((line = br.readLine()) != null) {
                lineno++;
                Object[] fields = parseLine(line, lineno, pathname);
                if (fields == null)
                    continue;
                persons.add(new Person((Integer)fields[0], (String)fields[1], (String)fields[2]));
            }
        }
        return persons;
    }
    
    private static Object[] parseLine(String line, int lineno, String pathname) {
        line = line.trim();
        if (line.startsWith("#"))
            return null;

        // id,firstName,lastName
        String[] items = line.split(",");
        if (items.length < 3)
            throw new IllegalArgumentException("Invalid data on line "+lineno+" in "+pathname);
        int id;
        try {
           id = new Integer(items[0]);
           if (id < 1)
               throw new IllegalArgumentException("Invalid data on line "+lineno+" in "+pathname);
        }
        catch (NumberFormatException e) {
            throw new IllegalArgumentException("Invalid data on line "+lineno+" in "+pathname);
        }
        
        Object[] fields = new Object[3];
        fields[0] = id;
        fields[1] = items[1].trim();
        fields[2] = items[2].trim();
        return fields;
    }

    /**
     * Convert a {@code List<Person>} to a {@code List<PersonId>}
     * @param persons the person list
     * @return the person id list
     */
    public static List<PersonId> toPersonIds(List<Person> persons) {
        return persons.stream()
            .map(person -> new PersonId(person.id))
            .collect(Collectors.toList());
    }
}