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package export;

import com.google.gson.Gson;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 *
 * @author cheok
 */
public class Export {

    private static class Duration {
        public final String start;
        public final String end;
        public Date date;

        Duration(String start, String end, Date date) {
            this.start = start;
            this.end = end;
            this.date = date;
        }
    }

    /**
     * <p>Checks if the first date is before the second date ignoring time.</p>
     * @param date1 the first date, not altered, not null
     * @param date2 the second date, not altered, not null
     * @return true if the first date day is before the second date day.
     * @throws IllegalArgumentException if the date is <code>null</code>
     */
    public static boolean isBeforeDay(Date date1, Date date2) {
        if (date1 == null || date2 == null) {
            throw new IllegalArgumentException("The dates must not be null");
        }
        Calendar cal1 = Calendar.getInstance();
        cal1.setTime(date1);
        Calendar cal2 = Calendar.getInstance();
        cal2.setTime(date2);
        return isBeforeDay(cal1, cal2);
    }

    /**
     * <p>Checks if the first calendar date is before the second calendar date ignoring time.</p>
     * @param cal1 the first calendar, not altered, not null.
     * @param cal2 the second calendar, not altered, not null.
     * @return true if cal1 date is before cal2 date ignoring time.
     * @throws IllegalArgumentException if either of the calendars are <code>null</code>
     */
    public static boolean isBeforeDay(Calendar cal1, Calendar cal2) {
        if (cal1 == null || cal2 == null) {
            throw new IllegalArgumentException("The dates must not be null");
        }
        if (cal1.get(Calendar.ERA) < cal2.get(Calendar.ERA)) return true;
        if (cal1.get(Calendar.ERA) > cal2.get(Calendar.ERA)) return false;
        if (cal1.get(Calendar.YEAR) < cal2.get(Calendar.YEAR)) return true;
        if (cal1.get(Calendar.YEAR) > cal2.get(Calendar.YEAR)) return false;
        return cal1.get(Calendar.DAY_OF_YEAR) < cal2.get(Calendar.DAY_OF_YEAR);
    }

    public static HashMap<String, Object> resultSetToHashMap(ResultSet rs) throws SQLException {
        ResultSetMetaData md = rs.getMetaData();
        int columns = md.getColumnCount();
        HashMap<String, Object> row = new HashMap<>();
        for (int i = 1; i <= columns; i++) {
            row.put(md.getColumnName(i), rs.getString(i));
        }
        return row;
    }

    private static List<Duration> split(Date date, int h) {
        List<Duration> durations = new ArrayList<>();

        Date currDate = date;

        DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
        Date[] dates = new Date[] {
            currDate,
        };

        for (Date d : dates) {
            String s = formatter.format(d);

            Duration duration0 = new Duration(s + " " + String.format("%02d", h) + ":00:00", s + " " + String.format("%02d", h) + ":59:59", d);

            durations.add(duration0);
        }

        return durations;
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws Exception {
        if (args.length < 2) {
            System.out.println("Usage: java -jar Export.jar yyyy-mm-dd hh");
            System.exit(0);
        }

        final DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
        final Date date = formatter.parse(args[0]);

        final int h = Integer.parseInt(args[1]);

        if (h < 0 || h > 23) {
            System.out.println("Hour must be 0 to 23");
            System.exit(0);
        }

        if (!isBeforeDay(date, new Date())) {
            System.out.println("Date must be older than today");
            System.exit(0);
        }

        System.out.println("...Going to generate hourly report with date \"" + date + "\". Hour is " + hour);

        final String servername = "rockman-api.sam-media.com";
        final String port = "3326";
        final String username = "rockman";
        final String password = "JjA1FAjyzhcInWti";
        final String db = "rockman";

        // This will load the MySQL driver, each DB has its own driver
        Class.forName("com.mysql.jdbc.Driver");
        // Setup the connection with the DB
        String url = "jdbc:mysql://" + servername + ":" + port + "/" + db;
        Connection connect = DriverManager.getConnection(url, username, password);

        final List<Duration> durations = split(date, h);

        System.out.println("Build output.json...");

        Gson gson = new Gson();
        BufferedWriter writer = null;
        File logFile = new File("output.json");
        writer = new BufferedWriter(new FileWriter(logFile));
        boolean firstTime = true;

        int counter = 0;

        for (Duration duration : durations) {
            String sql = "select *, DATE_FORMAT(timestamp, '%Y-%m-%dT%TZ') as time from rockman.matview_all_events where timestamp between ? and ? order by timestamp asc";
            PreparedStatement statement = connect.prepareStatement(sql);

            statement.setString(1, duration.start);
            statement.setString(2, duration.end);

            System.out.println("Going to run query (" + duration.start + ", " + duration.end + ")");
            long start = System.currentTimeMillis();
            ResultSet rs = statement.executeQuery();
            System.out.println("Time taken to run query (" + duration.start + ", " + duration.end + "): " + (System.currentTimeMillis() - start) + "ms");

            while (rs.next()){
                String event_type = rs.getString("event_type");

                if (event_type == null || event_type.isEmpty()) {
                    // Currently, we have no idea how to handle empty rockman id.
                    continue;
                }

                Map<String, Object> result = resultSetToHashMap(rs);

                if (event_type.equals("view")) {
                    result.put("view", 1);
                } else {
                    result.put("view", 0);
                }

                if (event_type.equals("lead")) {
                    result.put("lead", 1);
                } else {
                    result.put("lead", 0);
                }

                if (event_type.equals("subscription")) {
                    result.put("subscription", 1);
                } else {
                    result.put("subscription", 0);
                }

                if (event_type.equals("firstbilling")) {
                    result.put("firstbilling", 1);
                } else {
                    result.put("firstbilling", 0);
                }

                String s = gson.toJson(result);
                if (firstTime) {
                    writer.write(s);
                    firstTime = false;
                } else {
                    writer.write("\n" + s);
                }

                counter++;
            }

            rs.close();
        }   // for (Duration duration : durations)

        writer.close();

        System.out.println("Finish generating output.json with size " + counter);


        writer = new BufferedWriter(new FileWriter(new File("rockman-index.json")));

        FileReader fr = new FileReader("rockman-index.json.template");
        String s;
        BufferedReader br = new BufferedReader(fr);

        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        cal.add(Calendar.DATE, 1);
        Date nextDate = cal.getTime();
        String replace = formatter.format(date) + "T" + String.format("%02d", h) + ":00:00" + "/" + formatter.format(date) + "T" + String.format("%02d", h) + ":59:59";

        // 2016-04-13T00:00:00/2016-04-13T00:59:59
        while ((s = br.readLine()) != null) {
            s = s.replaceAll("%DATE_RANGE%", replace);
            writer.write(s + "\n");
        }

        br.close();
        writer.close();

        System.out.println("Finish generating rockman-index.json");
    }
}