package de.jeyp91.googlecalendar;

import com.google.api.client.util.DateTime;
import com.google.api.services.calendar.Calendar;
import com.google.api.services.calendar.model.Event;
import com.google.api.services.calendar.model.EventDateTime;
import com.google.api.services.calendar.model.EventReminder;
import com.google.api.services.calendar.model.Events;
import de.jeyp91.tippliga.TLWLeague;
import de.jeyp91.tippliga.TLWMatchday;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import java.io.IOException;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import static de.jeyp91.googlecalendar.GoogleCalendarConnector.getSerivce;

public class TippligaGoogleEventManager {

    private static List<Event> allEvents = null;
    private static final Logger logger = LogManager.getLogger(TippligaGoogleEventManager.class);

    public static List<Event> getAllEvents(Integer season) {
        if(allEvents == null) {
            allEvents = getAllEventsStartingFromDateTime(new DateTime(season-1 + "-07-01T00:00:00Z"));
        }
        return allEvents;
    }

    public static List<Event> getAllEventsStartingFromDateTime(DateTime dateTime) {

        Calendar service = getSerivce();
        Events events = null;

        String calendarUrl = CalendarConfigProvider.getCalendarUrl();

        // Build a new authorized API client service.
        try {
            events = service.events().list(calendarUrl)
                    .setMaxResults(500)
                    .setTimeMin(dateTime)
                    .setOrderBy("startTime")
                    .setSingleEvents(true)
                    .execute();

        } catch (IOException e) {
            e.printStackTrace();
        }

        assert events != null;
        return events.getItems();
    }

    public static Event findEvent(List<Event> allEvents, Integer season, Integer league, Integer matchday, Integer deliveryDateNumber) {
        String description = getDescription(season, league, matchday, deliveryDateNumber);
        String descriptionHtml = getDescriptionHTML(season, league, matchday, deliveryDateNumber);
        for (Event event : allEvents) {
            String eventDescription = event.getDescription();
            if (
                    (eventDescription.replaceAll("\\s+","").equals(description.replaceAll("\\s+","")))
                    || eventDescription.equals(descriptionHtml)
            ) {
                return event;
            }
        }
        return null;
    }

    public static void createOrUpdateEventsForMatchday(TLWMatchday matchday) {
        createOrUpdateEvent(matchday, matchday.getDeliveryDate(), 1);
        if(!matchday.getDeliveryDate2().equals("")) createOrUpdateEvent(matchday, matchday.getDeliveryDate2(), 2);
        if(!matchday.getDeliveryDate3().equals("")) createOrUpdateEvent(matchday, matchday.getDeliveryDate3(), 3);
    }

    public static void createOrUpdateEvent(TLWMatchday matchday, String deliveryDateString, Integer deliverDateNumber) {
        List<Event> allEvents = getAllEvents(matchday.getSeason());
        Event event = findEvent(allEvents, matchday.getSeason(), matchday.getLeague(), matchday.getMatchday(), deliverDateNumber);
        if(event == null) {
            createNewEvent(matchday, deliveryDateString, deliverDateNumber);
        }
        else {
            String googleEventStart = event.getStart().getDateTime().toString();
            String googleEventStartBeautified = googleEventStart.substring(0, 19).replace("T", " ");
            if(!googleEventStartBeautified.equals(deliveryDateString)) {
                updateEvent(event, matchday, deliveryDateString, deliverDateNumber);
            }
        }
    }

    private static void createNewEvent(TLWMatchday matchday, String deliveryDateString, Integer deliverDateNumber) {
        String calendarUrl = CalendarConfigProvider.getCalendarUrl();

        Event event = getEvent(matchday, deliveryDateString, deliverDateNumber);

        try {
            logger.info("Create new google calendar event for " + matchday.getSeason() + ", " + matchday.getLeague() + ", " + matchday.getMatchday() + ", " + deliverDateNumber);
            getSerivce().events().insert(calendarUrl, event).execute();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void updateEvent(Event oldEvent, TLWMatchday matchday, String deliveryDateString, Integer deliverDateNumber) {
        String calendarUrl = CalendarConfigProvider.getCalendarUrl();

        Event event = getEvent(matchday, deliveryDateString, deliverDateNumber);

        try {
            logger.info("Update google calendar event for " + matchday.getSeason() + ", " + matchday.getLeague() + ", " + matchday.getMatchday() + ", " + deliverDateNumber);
            Calendar.Events events = getSerivce().events();
            events.update(calendarUrl, oldEvent.getId(), event).execute();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void deleteEvent(TLWMatchday matchday, Integer deliverDateNumber) {
        String calendarUrl = CalendarConfigProvider.getCalendarUrl();

        Event event = findEvent(getAllEvents(matchday.getSeason()), matchday.getSeason(), matchday.getLeague(), matchday.getMatchday(), deliverDateNumber);
        if(event != null) {
            try {
                logger.info("Delete google calendar event for " + matchday.getSeason() + ", " + matchday.getLeague() + ", " + matchday.getMatchday() + ", " + deliverDateNumber);
                getSerivce().events().delete(calendarUrl, event.getId()).execute();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static void deleteAllEvents(int season) throws IOException {
        String calendarUrl = CalendarConfigProvider.getCalendarUrl();
        List<Event> events = getAllEvents(season);
        for(Event event : events ) {
            getSerivce().events().delete(calendarUrl, event.getId()).execute();
        }
    }

    private static Event getEvent(TLWMatchday matchday, String deliveryDateString, Integer deliverDateNumber) {
        String matchdayName = matchday.getMatchdayName().equals("") ? matchday.getMatchday().toString() + ". Spieltag" : matchday.getMatchdayName();
        String summary = TLWLeague.getLeagueNameCalendar(matchday.getLeague()) + " " + matchdayName + " tippen!";
        if(deliverDateNumber > 1) summary += " " + deliverDateNumber + ". Chance \uD83D\uDE43";
        String description = getDescription(matchday.getSeason(), matchday.getLeague(), matchday.getMatchday(), deliverDateNumber);
        String location = "https://tippliga-wuerzburg.de/app.php/football/bet";

        LocalDateTime deliveryLocalDateTime = LocalDateTime.parse(deliveryDateString.replace(" ", "T"));
        ZonedDateTime zdtBerlin = ZonedDateTime.of(deliveryLocalDateTime, ZoneId.of("Europe/Berlin"));
        DateTime deliveryDateTime = new DateTime(zdtBerlin.toInstant().toEpochMilli());
        EventDateTime date = new EventDateTime()
                .setDateTime(deliveryDateTime)
                .setTimeZone("Europe/Berlin");

        // Set reminder to 12 hours before
        Event.Reminders reminders = new Event.Reminders();
        reminders.setUseDefault(true);

        return new Event()
                .setSummary(summary)
                .setLocation(location)
                .setDescription(description)
                .setStart(date)
                .setEnd(date)
                .setReminders(reminders);
    }

    private static String getDescription(Integer season, Integer league, Integer matchday, Integer deliverDateNumber) {
        league = league == 2 ? 1 : league;
        return "Saison: " + season + "\n" + "Liga: " + league + "\n" + "Spieltag: " + matchday + "\n" + "Abgabeschluss: " + deliverDateNumber;
    }


    private static String getDescriptionHTML(Integer season, Integer league, Integer matchday, Integer deliverDateNumber) {
        league = league == 2 ? 1 : league;
        return "Saison: " + season + "<br>" + "Liga: " + league + "<br>" + "Spieltag: " + matchday + "<br>" + "Abgabeschluss: " + deliverDateNumber;
    }

    public static void updateAllMatchdays(ArrayList<TLWMatchday> matchdays) {
        matchdays.forEach(tlwMatchday -> {
            createOrUpdateEvent(tlwMatchday, tlwMatchday.getDeliveryDate(), 1);
            if(tlwMatchday.getDeliveryDate2().equals("")) {
                deleteEvent(tlwMatchday, 2);
            } else {
                createOrUpdateEvent(tlwMatchday, tlwMatchday.getDeliveryDate2(), 2);
            }
            if(tlwMatchday.getDeliveryDate3().equals("")) {
                deleteEvent(tlwMatchday, 3);
            } else {
                createOrUpdateEvent(tlwMatchday, tlwMatchday.getDeliveryDate3(), 3);
            }
        });
    }
}