/**
 * Copyright (C) 2016 eBusiness Information
 *
 * This file is part of OSM Contributor.
 *
 * OSM Contributor is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * OSM Contributor is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with OSM Contributor.  If not, see <http://www.gnu.org/licenses/>.
 */
package io.jawg.osmcontributor.utils.helper;

import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.helper.ItemTouchHelper;

public class DragSwipeItemTouchHelperCallback extends ItemTouchHelper.Callback {

    private final DragSwipeItemTouchHelperAdapter adapter;
    private Integer fromPosition = null;
    private Integer toPosition = null;

    public DragSwipeItemTouchHelperCallback(DragSwipeItemTouchHelperAdapter adapter) {
        this.adapter = adapter;
    }

    @Override
    public boolean isLongPressDragEnabled() {
        return false;
    }

    @Override
    public boolean isItemViewSwipeEnabled() {
        return true;
    }

    @Override
    public int getMovementFlags(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
        final int dragFlags = ItemTouchHelper.UP | ItemTouchHelper.DOWN;
        final int swipeFlags = ItemTouchHelper.START | ItemTouchHelper.END;
        return makeMovementFlags(dragFlags, swipeFlags);
    }

    @Override
    public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder source, RecyclerView.ViewHolder target) {
        if (source.getItemViewType() != target.getItemViewType()) {
            return false;
        }

        // remember FIRST from position
        if (fromPosition == null) {
            fromPosition = source.getAdapterPosition();
        }
        toPosition = target.getAdapterPosition();

        // Notify the adapter of the move
        adapter.onItemMove(source.getAdapterPosition(), target.getAdapterPosition());
        return true;
    }

    @Override
    public void onSwiped(RecyclerView.ViewHolder viewHolder, int i) {
        adapter.onItemDismiss(viewHolder.getAdapterPosition());
    }

    @Override
    public void onSelectedChanged(RecyclerView.ViewHolder viewHolder, int actionState) {
        if (actionState != ItemTouchHelper.ACTION_STATE_IDLE) {
            ItemTouchHelperViewHolder itemViewHolder = (ItemTouchHelperViewHolder) viewHolder;
            itemViewHolder.onItemSelected();
        }

        super.onSelectedChanged(viewHolder, actionState);
    }

    @Override
    public void clearView(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) {
        super.clearView(recyclerView, viewHolder);

        ItemTouchHelperViewHolder itemViewHolder = (ItemTouchHelperViewHolder) viewHolder;
        itemViewHolder.onItemClear();

        if (fromPosition != null && toPosition != null) {
            adapter.onItemDrop(fromPosition, toPosition);
        }

        // clear saved positions
        fromPosition = null;
        toPosition = null;
    }
}