import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.support.annotation.ColorInt;
import android.support.v4.view.ViewCompat;
import android.support.v7.widget.RecyclerView;
import android.view.View;

public class DividerItemDecoration extends RecyclerView.ItemDecoration {

    public static final int HORIZONTAL = 1;
    public static final int VERTICAL = 2;
    public static final int BOTH = 3;

    private Paint paint;
    private int dividerHeight;
    private int orientation;

    private DividerItemDecoration() {
        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        paint.setStyle(Paint.Style.FILL);
    }

    public void setDividerHeight(int dividerHeight) {
        this.dividerHeight = dividerHeight;
    }

    public void setColor(int color) {
        paint.setColor(color);
    }

    public int getOrientation() {
        return orientation;
    }

    public void setOrientation(int orientation) {
        this.orientation = orientation;
    }

    @Override
    public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
        if (orientation == VERTICAL) {
            drawVertical(c, parent);
        } else if (orientation == HORIZONTAL) {
            drawHorizontal(c, parent);
        } else if (orientation == BOTH) {
            drawVertical(c, parent);
            drawHorizontal(c, parent);
        }
    }

    protected void drawVertical(Canvas c, RecyclerView parent) {
        final int left = parent.getPaddingLeft();
        final int right = parent.getWidth() - parent.getPaddingRight();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = parent.getChildAt(i);
            if (parent.getChildAdapterPosition(child) == (parent.getAdapter().getItemCount() - 1)) {
                continue;
            }
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
            final int bottom;
            final int top;
            top = child.getBottom() + params.bottomMargin + Math.round(ViewCompat.getTranslationY(child));
            bottom = top + dividerHeight;
            c.drawRect(left, top, right, bottom, paint);
        }
    }

    protected void drawHorizontal(Canvas c, RecyclerView parent) {
        final int top = parent.getPaddingTop();
        final int bottom = parent.getHeight() - parent.getPaddingBottom();
        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = parent.getChildAt(i);
            if (parent.getChildAdapterPosition(child) == (parent.getAdapter().getItemCount() - 1)) {
                continue;
            }
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int right;
            final int left;
            left = child.getRight() + params.rightMargin + Math.round(ViewCompat.getTranslationX(child));
            right = left + dividerHeight;
            c.drawRect(left, top, right, bottom, paint);
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        if (orientation == VERTICAL) {
            outRect.set(0, 0, 0, dividerHeight);
        } else if (orientation == HORIZONTAL){
            outRect.set(0, 0, dividerHeight, 0);
        } else if (orientation == BOTH) {
            outRect.set(0, 0, dividerHeight, dividerHeight);
        }
    }

    public static class Builder {

        private int dividerHeight;
        private int color;
        private int orientation;

        public Builder dividerHeight(int dividerHeight) {
            this.dividerHeight = dividerHeight;
            return this;
        }

        public Builder color(@ColorInt int color) {
            this.color = color;
            return this;
        }

        public Builder orientation(int orientation) {
            this.orientation = orientation;
            return this;
        }

        public DividerItemDecoration build() {
            DividerItemDecoration divider = new DividerItemDecoration();

            if (dividerHeight == 0) {
                // Set default divider height to 1px.
                divider.setDividerHeight(1);
            } else if (dividerHeight > 0) {
                divider.setDividerHeight(dividerHeight);
            } else {
                throw new IllegalArgumentException("Divider's height can't be negative.");
            }

            if (color == 0) {
                throw new IllegalArgumentException("Don't forget to set color");
            } else {
                divider.setColor(color);
            }

            if (orientation != HORIZONTAL && orientation != VERTICAL && orientation != BOTH) {
                throw new IllegalArgumentException("Invalid orientation");
            } else {
                divider.setOrientation(orientation);
            }

            return divider;
        }
    }
}