/*
 * [Comb.java]
 *
 * Summary: Combs a list of email addresses and returns a list of valid ones, logging bad ones.
 *
 * Copyright: (c) 2002-2017 Roedy Green, Canadian Mind Products, http://mindprod.com
 *
 * Licence: This software may be copied and used freely for any purpose but military.
 *          http://mindprod.com/contact/nonmil.html
 *
 * Requires: JDK 1.8+
 *
 * Created with: JetBrains IntelliJ IDEA IDE http://www.jetbrains.com/idea/
 *
 * Version History:
 *  1.7 2007-08-21
 */
package com.mindprod.bulk;

import com.mindprod.csv.CSVReader;

import javax.mail.internet.InternetAddress;
import java.io.EOFException;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.Date;

import static com.mindprod.bulk.CustConfig.CUST_NAME;
import static com.mindprod.bulk.CustConfig.EMAIL_ADDRESS_QUALITY;
import static com.mindprod.bulk.CustConfig.MAX_EMAILS_IN_BATCH;
import static com.mindprod.bulk.CustConfig.MONITORS;
import static java.lang.System.*;

/**
 * Combs a list of email addresses and returns a list of valid ones, logging bad ones.
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.7 2007-08-21
 * @since 2002
 */
final class Comb
    {
    /**
     * Combs a list of email addresses and returns a list of deliverable ones, logging bad ones. It works via
     * CachedEmailProber ensuring Email servers are working.
     *
     * @param ir  source of email addresses, CSV, comma delimited, four fields, email, dear, fullname, account Typically
     *            ByteArrayInputStream attachment or FileInputStream abundance emails.txt export.
     * @param log Where to log the errors.
     *
     * @return ArrayList of InternetAddresses  of deliverable emails.
     */
    @SuppressWarnings( { "InfiniteLoopStatement", "SameParameterValue", "QuestionableName" } )
    public static ArrayList<InternetAddress> comb( Reader ir, Log log )
        {
        try
            {
            final ArrayList<InternetAddress> result =
                    new ArrayList<>( MAX_EMAILS_IN_BATCH
                                     + MONITORS
                                             .length
                                     + 1 );
            final CSVReader r = new CSVReader( ir );
            int good = 0;
            int bad = 0;
            try
                {
                log.println( "" );
                log.println( new Date().toString() + " " + CUST_NAME );
                while ( true )
                    {
                    String email = r.get();
                    // ignore empty lines especially at end of file.
                    if ( email == null )
                        {
                        continue;
                        }
                    String dear = r.get();
                    String fullname = r.get();
                    String acct = r.get();
                    r.skipToNextLine();
                    // don't echo to log
                    out.println( "     checking " + email );
                    // higher the number better it is 0..9
                    final int howGood = EmailSyntaxValidator.howValid( email );
                    if ( howGood > EMAIL_ADDRESS_QUALITY )
                        {
                        if ( CachedMailProber.isMailServerForEmailAlive( email ) )
                            {
                            result.add( new InternetAddress(
                                    email,
                                    /* human */
                                    dear ) );
                            good++;
                            }
                        else
                            {
                            log.println(
                                    ">>>recipient's mail server not working.  goodness:"
                                    + howGood
                                    + " "
                                    + email
                                    + ","
                                    + dear
                                    + ","
                                    + fullname
                                    + ","
                                    + acct
                            );
                            bad++;
                            }
                        }
                    else
                        {
                        /* don't even bother probing the really hopeless stuff */
                        log.println(
                                ">>>recipient rejected based on form of address.  goodness:"
                                + howGood
                                + " "
                                + email
                                + ","
                                + dear
                                + ","
                                + fullname
                                + ","
                                + acct
                        );
                        bad++;
                        }
                    } // end while
                }
            catch ( EOFException e )
                {
                log.println( good
                             + " emails passed inspection, "
                             + bad
                             + " emails rejected." );
                log.println( "" );
                r.close();
                // don't close. We will need it again for the next message.
                CachedMailProber.flush();
                return result;
                }
            }
        catch ( IOException e )
            {
            err.println();
            e.printStackTrace( err );
            err.println();
            log.println( "Likely malformed list of emails" );
            return null;
            }
        } // end comb
    } // end Comb