package ru.yarmiit.ztrap.mvp.ui.adapters.realm;

import android.databinding.DataBindingUtil;
import android.databinding.ViewDataBinding;
import android.support.annotation.LayoutRes;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.ViewGroup;

import java.util.Arrays;
import java.util.List;

import io.realm.OrderedCollectionChangeSet;
import io.realm.OrderedRealmCollectionChangeListener;
import io.realm.RealmObject;
import io.realm.RealmResults;
import ru.yarmiit.ztrap.mvp.analytics.Events;
import ru.yarmiit.ztrap.mvp.ui.adapters.abs.AbstractHolder;

/**
 * @author zTrap
 * @date 16.04.2017.
 */
@SuppressWarnings("ConstantConditions, unchecked")
public abstract class AbstractRealmAdapter<T extends RealmObject, H extends AbstractHolder>
        extends RecyclerView.Adapter<H> {

    protected RealmResults<T> mItems;

    protected OrderedRealmCollectionChangeListener<RealmResults<T>> mListener = (collection, changeSet) -> {
        if (changeSet == null){
            notifyDataSetChanged();
            return;
        }

        for (OrderedCollectionChangeSet.Range range : changeSet.getDeletionRanges()) {
            notifyItemRangeRemoved(range.startIndex, range.length);
        }

        for (OrderedCollectionChangeSet.Range range : changeSet.getInsertionRanges()) {
            notifyItemRangeInserted(range.startIndex, range.length);
        }

        for (OrderedCollectionChangeSet.Range range : changeSet.getChangeRanges()) {
            notifyItemRangeChanged(range.startIndex, range.length);
        }
    };

    protected AbstractRealmAdapter(){
        setHasStableIds(true);
        mItems = getRealmItems();
    }

    @Override
    public long getItemId(int index) {
        return index;
    }

    @Override
    public void onAttachedToRecyclerView(final RecyclerView recyclerView) {
        mItems.addChangeListener(mListener);
    }

    @Override
    public void onDetachedFromRecyclerView(final RecyclerView recyclerView) {
        mItems.removeChangeListener(mListener);
    }

    protected final <V extends ViewDataBinding> V createBinding(@LayoutRes int layoutId, ViewGroup parent) {
        return DataBindingUtil.inflate(LayoutInflater.from(parent.getContext()), layoutId, parent, false);
    }

    protected abstract RealmResults<T> getRealmItems();

    @Override
    public final void onBindViewHolder(H holder, int position) {
        T item = mItems.get(position);
        if (!item.isValid()){
            Events.log(getClass().getSimpleName() + ", item is invalid");
            return;
        }
        holder.fillHolder(item);
    }

    public List<T> getItems() {
        return mItems;
    }

    @Override
    public final int getItemCount() {
        return mItems == null ? 0 : mItems.size();
    }

    public final boolean isEmpty(){
        return getItemCount() == 0;
    }
}