package com.home.rxtwitch.ui;

import android.graphics.Rect;
import android.support.v7.widget.RecyclerView;
import android.view.View;

/**
 * Created by xmax on 3/6/16.
 */
public class GridItemOffsetDecoration extends RecyclerView.ItemDecoration{
   /* private int mItemOffset;

    public GridItemOffsetDecoration(int itemOffset) {
        mItemOffset = itemOffset;
    }

    public GridItemOffsetDecoration(@NonNull Context context, @DimenRes int itemOffsetId) {
        this(context.getResources().getDimensionPixelSize(itemOffsetId));
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent,
                               RecyclerView.State state) {
        super.getItemOffsets(outRect, view, parent, state);
        outRect.set(mItemOffset, mItemOffset, mItemOffset, mItemOffset);
    }*/

    private int spanCount;
    private int spacing;
    private boolean includeEdge;

    public GridItemOffsetDecoration(int spanCount, int spacing, boolean includeEdge) {
        this.spanCount = spanCount;
        this.spacing = spacing;
        this.includeEdge = includeEdge;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        int position = parent.getChildAdapterPosition(view); // item position
        int column = position % spanCount ; // item column

        if (includeEdge) {
            outRect.left = spacing - column * spacing / spanCount; // spacing - column * ((1f / spanCount) * spacing)
            outRect.right = (column + 1) * spacing / spanCount; // (column + 1) * ((1f / spanCount) * spacing)

            //outRect.left = spacing * (1 - column / spanCount); // spacing - column * ((1f / spanCount) * spacing)
            //outRect.right = spacing * ((column + 1) / spanCount); // (column + 1) * ((1f / spanCount) * spacing)

            if (position < spanCount) { // top edge
                outRect.top = spacing;
            }

            outRect.bottom = spacing; // item bottom
            //Log.e("position", " position" +position+"column"+ column + "left" + outRect.left + "top" + outRect.top + "right" + outRect.right + "bottom" + outRect.bottom );

        } else {
            outRect.left = column * spacing / spanCount; // column * ((1f / spanCount) * spacing)
            outRect.right = spacing - (column + 1) * spacing / spanCount; // spacing - (column + 1) * ((1f /    spanCount) * spacing)
            if (position >= spanCount) {
                outRect.top = spacing; // item top
            }
        }

    }
}
