watchdog/src/main/java/cz/senslog/watchdog/messagebroker/broker/EmailMessageBroker.java

package cz.senslog.watchdog.messagebroker.broker;

import cz.senslog.watchdog.config.EmailMessageBrokerConfig;
import cz.senslog.watchdog.config.MessageBrokerType;
import cz.senslog.watchdog.core.connection.EmailServerConnection;
import cz.senslog.watchdog.domain.*;
import cz.senslog.watchdog.messagebroker.MessageBroker;
import cz.senslog.watchdog.messagebroker.MessageBrokerHandler;
import cz.senslog.watchdog.messagebroker.MessageStatus;
import cz.senslog.watchdog.messagebroker.writer.HtmlTableWriter;
import cz.senslog.watchdog.messagebroker.writer.TableWriter;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import javax.mail.*;
import java.util.*;

import static java.time.format.DateTimeFormatter.ofPattern;

public class EmailMessageBroker implements MessageBroker {

    private static final String BREAK_LINE = "<br />";

    private static final Logger logger = LogManager.getLogger(EmailMessageBroker.class);

    private final EmailServerConnection serverConnection;
    private final EmailMessageBrokerConfig messageConfig;

    public EmailMessageBroker(EmailServerConnection serverConnection, EmailMessageBrokerConfig messageConfig) {
        this.serverConnection = serverConnection;
        this.messageConfig = messageConfig;
    }

    private String createMessage(Report report) {
        StringBuilder content = new StringBuilder();
        final String rowStyle = "border: 1px solid #dddddd; text-align: left; padding: 8px;";

        boolean isMessages = !report.getMessages().isEmpty();
        boolean isRecords = !report.getReports().isEmpty();

        if (!report.getOperationProperties().isEmpty()) {

            TableWriter tableSourceWriter = HtmlTableWriter.createWithHeader("width: 100%;", "background-color: #dddddd")
                    .cell("Operation Type").cell("Operation Value").end();

            for (Map.Entry<String, String> operationEntry : report.getOperationProperties().entrySet()) {
                tableSourceWriter.row(rowStyle)
                            .cell(operationEntry.getKey(), rowStyle)
                            .cell(operationEntry.getValue(), rowStyle)
                        .end();
            }

            content.append(tableSourceWriter.table()).append(BREAK_LINE);
        }

        if (isMessages || !isRecords) {
            TableWriter tableMsgWriter = HtmlTableWriter.createWithHeader("width: 100%;", "background-color: #dddddd")
                    .cell("Messages").end();

            for (String message : report.getMessages()) {
                tableMsgWriter.row(rowStyle).cell(message, rowStyle).end();
            }

            if (!isRecords) {
                tableMsgWriter.row(rowStyle).cell("All received observations are valid.");
            }

            content.append(tableMsgWriter.table()).append(BREAK_LINE);
        }

        if (isRecords) {
            TableWriter tableReportWriter = HtmlTableWriter.createWithHeader("width: 100%;", "background-color: #dddddd")
                    .cell("unitName (unitId)").cell("sensorName (sensorId)").cell("timestamp").cell("reported").cell("status").end();

            String reportedTime = report.getCreated().format(ofPattern("yyyy-MM-dd HH:mm:ss"));

            report.getReports().sort(Comparator.comparing(SimpleReport::getStatus).reversed());
            for (SimpleReport simpleReport : report.getReports()) {
                boolean isOk = simpleReport.getStatus().equals(StatusReport.OK);
                if (simpleReport.getRecord() instanceof ObservationInfo) {
                    ObservationInfo observation = (ObservationInfo) simpleReport.getRecord();
                    Source source = observation.getSource();

                    String unitCell = String.format("%s (%s)", source.getUnit().getName(), source.getUnit().getId());
                    String sensorCell = String.format("%s (%s)", source.getSensor().getName(), source.getSensor().getId());

                    tableReportWriter.row(rowStyle + "background-color: " + (isOk ? "#CCFFCC" : "#FFCCCC"))
                            .cell(unitCell, rowStyle)
                            .cell(sensorCell, rowStyle)
                            .cell(observation.getTimestamp().toString(), rowStyle)
                            .cell(reportedTime, rowStyle)
                            .cell(simpleReport.getStatus().name(), rowStyle)
                            .end();
                }
            }
            content.append(tableReportWriter.table()).append(BREAK_LINE);
        }

        return content.toString();
    }

    @Override
    public void send(Report report, MessageBrokerHandler status) {
        if (report == null) {
            logger.info("Nothing to send. The receive report is null.");
            status.handle(new MessageStatus(null, "No report to send.")); return;
        }

        try {
            logger.info("Sending a message via email.");
            serverConnection.send(createMessage(report), messageConfig);
            logger.info("The message was send successfully.");
            status.handle(new MessageStatus(report));
        } catch (MessagingException e) {
            logger.catching(e);
            status.handle(new MessageStatus(report, e.getMessage()));
        }
    }

    @Override
    public MessageBrokerType getType() {
        return MessageBrokerType.EMAIL;
    }
}