using System.ComponentModel;

namespace System.Windows.Forms
{
    [TypeConverter(typeof(PaddingConverter))]
    public struct Padding
    {
        private bool _all;

        private int _top;

        private int _left;

        private int _right;

        private int _bottom;

        public static readonly Padding Empty = new Padding(0);

        public int All
        {
            get
            {
                if (!_all)
                {
                    return -1;
                }

                return _top;
            }
            set
            {
                if (!_all || _top != value)
                {
                    _all = true;
                    _top = (_left = (_right = (_bottom = value)));
                }
            }
        }

        public int Bottom
        {
            get
            {
                if (_all)
                {
                    return _top;
                }

                return _bottom;
            }
            set
            {
                if (_all || _bottom != value)
                {
                    _all = false;
                    _bottom = value;
                }
            }
        }

        public int Left
        {
            get
            {
                if (_all)
                {
                    return _top;
                }

                return _left;
            }
            set
            {
                if (_all || _left != value)
                {
                    _all = false;
                    _left = value;
                }
            }
        }

        public int Right
        {
            get
            {
                if (_all)
                {
                    return _top;
                }

                return _right;
            }
            set
            {
                if (_all || _right != value)
                {
                    _all = false;
                    _right = value;
                }
            }
        }

        public int Top
        {
            get
            {
                return _top;
            }
            set
            {
                if (_all || _top != value)
                {
                    _all = false;
                    _top = value;
                }
            }
        }

        public int Horizontal => Left + Right;

        public int Vertical => Top + Bottom;

        public Size Size => new Size(Horizontal, Vertical);

        public Padding(int all)
        {
            _all = true;
            _top = (_left = (_right = (_bottom = all)));
        }

        public Padding(int left, int top, int right, int bottom)
        {
            _top = top;
            _left = left;
            _right = right;
            _bottom = bottom;
            _all = _top == _left && _top == _right && _top == _bottom;
        }

        public override bool Equals(object other)
        {
            if (other is not Padding otherPadding)
            {
                return false;
            }

            return Equals(otherPadding);
        }

        public bool Equals(Padding other)
            => Left == other.Left
                && Top == other.Top
                && Right == other.Right
                && Bottom == other.Bottom;

        public static Padding operator +(Padding p1, Padding p2)
        {
            return new Padding(p1.Left + p2.Left, p1.Top + p2.Top, p1.Right + p2.Right, p1.Bottom + p2.Bottom);
        }

        public static Padding operator -(Padding p1, Padding p2)
        {
            return new Padding(p1.Left - p2.Left, p1.Top - p2.Top, p1.Right - p2.Right, p1.Bottom - p2.Bottom);
        }

        public static bool operator ==(Padding p1, Padding p2)
        {
            return p1.Left == p2.Left && p1.Top == p2.Top && p1.Right == p2.Right && p1.Bottom == p2.Bottom;
        }

        public static bool operator !=(Padding p1, Padding p2) => !(p1 == p2);

        public override int GetHashCode()
        {
            var hashCode = 1903003160;
            hashCode = hashCode * -1521134295 + Left.GetHashCode();
            hashCode = hashCode * -1521134295 + Top.GetHashCode();
            hashCode = hashCode * -1521134295 + Right.GetHashCode();
            hashCode = hashCode * -1521134295 + Bottom.GetHashCode();
            return hashCode;
        }
        internal bool ShouldSerializeAll()
        {
            return _all;
        }

    }

}