package org.mercury_im.messenger.data.repository;

import org.mercury_im.messenger.data.mapping.GroupChatMapping;
import org.mercury_im.messenger.data.model.GroupChatModel;
import org.mercury_im.messenger.data.repository.dao.GroupChatDao;
import org.mercury_im.messenger.util.Optional;
import org.mercury_im.messenger.entity.Account;
import org.mercury_im.messenger.entity.chat.GroupChat;
import org.mercury_im.messenger.entity.chat.IGroupChat;
import org.mercury_im.messenger.util.ThreadUtils;

import java.util.ArrayList;
import java.util.List;

import javax.inject.Inject;
import javax.inject.Named;

import io.reactivex.Completable;
import io.reactivex.Maybe;
import io.reactivex.Observable;
import io.reactivex.Scheduler;
import io.reactivex.Single;
import io.requery.Persistable;
import io.requery.query.ResultDelegate;
import io.requery.reactivex.ReactiveEntityStore;

public class XmppGroupChatRepository
        extends RequeryRepository
        implements GroupChatRepository {

    private final GroupChatMapping groupChatMapping;

    private final GroupChatDao dao;

    @Inject
    public XmppGroupChatRepository(
            ReactiveEntityStore<Persistable> data,
            @Named(value = ThreadUtils.SCHEDULER_IO) Scheduler subscriberScheduler,
            @Named(value = ThreadUtils.SCHEDULER_UI) Scheduler observerScheduler,
            GroupChatMapping groupChatMapping) {
        super(data, subscriberScheduler, observerScheduler);
        this.groupChatMapping = groupChatMapping;
        this.dao = new GroupChatDao(data);
    }

    @Override
    public Single<GroupChat> insertGroupChat(GroupChat chat) {
        return Single.just(chat)
                .map(groupChatMapping::toModel)
                .flatMap(dao::insert)
                .map(model -> groupChatMapping.toEntity(model, chat))
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Observable<Optional<GroupChat>> observeGroupChat(long chatId) {
        return dao.get(chatId).observableResult()
                .map(ResultDelegate::firstOrNull)
                .map(groupChatMapping::toEntity)
                .map(Optional::new)
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Maybe<GroupChat> getGroupChat(long chatId) {
        return dao.get(chatId).maybe()
                .map(groupChatMapping::toEntity)
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Single<GroupChat> getOrCreateGroupChat(Account account, String roomAddress) {
        return getGroupChatByRoomAddress(account, roomAddress)
                .switchIfEmpty(
                        Single.just((GroupChat) new IGroupChat() {
                            {
                                setAccount(account);
                                setRoomAddress(roomAddress);
                            }
                        })
                        .flatMap(this::insertGroupChat))
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Observable<Optional<GroupChat>> observeGroupChatByRoomAddress(long accountId, String roomAddress) {
        return dao.get(accountId, roomAddress).observableResult()
                .map(ResultDelegate::firstOrNull)
                .map(groupChatMapping::toEntity)
                .map(Optional::new)
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Maybe<GroupChat> getGroupChatByRoomAddress(long accountId, String roomAddress) {
        return dao.get(accountId, roomAddress).maybe()
                .map(groupChatMapping::toEntity)
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Observable<List<GroupChat>> observeAllGroupChats() {
        return dao.getAll().observableResult()
                .map(ResultDelegate::toList)
                .map(list -> {
                    List<GroupChat> entities = new ArrayList<>(list.size());
                    for (GroupChatModel model : list) {
                        entities.add(groupChatMapping.toEntity(model));
                    }
                    return entities;
                })
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Single<GroupChat> updateGroupChat(GroupChat chat) {
        return dao.get(chat.getId()).maybe().toSingle()
                .map(model -> groupChatMapping.toModel(chat, model))
                .flatMap(data()::update)
                .map(model -> groupChatMapping.toEntity(model, chat))
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Single<GroupChat> upsertGroupChat(GroupChat chat) {
        return dao.get(chat.getId()).maybe()
                .switchIfEmpty(Single.just(chat).map(groupChatMapping::toModel)
                        .flatMap(dao::insert))
                .map(model -> groupChatMapping.toModel(chat, model))
                .flatMap(data()::update)
                .map(model -> groupChatMapping.toEntity(model, chat))
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }

    @Override
    public Completable deleteGroupChat(GroupChat chat) {
        return dao.delete(chat.getId()).ignoreElement()
                .subscribeOn(subscriberScheduler())
                .observeOn(observerScheduler());
    }
}