/******************************************************************************
 * Copyright (C) Ultraleap, Inc. 2011-2021.                                   *
 *                                                                            *
 * Use subject to the terms of the Apache License 2.0 available at            *
 * http://www.apache.org/licenses/LICENSE-2.0, or another agreement           *
 * between Ultraleap and you, your company or other organization.             *
 ******************************************************************************/

using UnityEngine;

namespace Leap.Unity.Geometry
{

    public struct Margins
    {

        public float left;
        public float right;
        public float top;
        public float bottom;

        public static readonly Margins zero = Margins.All(0f);
        public static readonly Margins one = Margins.All(1f);

        public Margins(float left, float right, float top, float bottom)
        {
            this.left = left; this.right = right; this.top = top; this.bottom = bottom;
        }

        public static Margins All(float margin)
        {
            return new Margins()
            {
                left = margin,
                right = margin,
                top = margin,
                bottom = margin
            };
        }

        public static Margins operator *(Margins m, float factor)
        {
            return new Margins(m.left * factor, m.right * factor, m.top * factor,
              m.bottom * factor);
        }

        public static Margins operator *(float factor, Margins m)
        {
            return new Margins(m.left * factor, m.right * factor, m.top * factor,
              m.bottom * factor);
        }

        public static Margins operator -(Margins m)
        {
            return m * -1f;
        }

    }

    public static class MarginExtensions
    {

        public static LocalRect PadOuter(this LocalRect r, Margins margins)
        {
            return new LocalRect(
              center: r.center + new Vector3(
                (margins.right - margins.left) / 2f,
                (margins.top - margins.bottom) / 2f,
                0f
              ),
              radii: new Vector2(
                r.radii.x + (margins.right + margins.left) / 2f,
                r.radii.y + (margins.top + margins.bottom) / 2f
              )
            );
        }

        public static LocalRect PadInner(this LocalRect r, Margins margins)
        {
            return r.PadOuter(-margins);
        }

    }

}