using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;

namespace Superlazy
{
    public abstract class SLEntity : IEnumerable<SLEntity>, IComparable<SLEntity>
    {
        public abstract bool IsNumeric { get; }
        public abstract bool IsValue { get; }
        public abstract string ID { get; }

        public abstract bool IsModified(string child);

        public abstract void EndModified();

        public abstract bool HasChild(string attributeKey);

        internal abstract object GetObj();

        internal abstract int GetInt();

        internal abstract double GetDouble();

        internal abstract string GetString();

        internal abstract bool IsExist();

        protected abstract int GetEntityHashCode();

        internal static IEnumerable<SLEntity> emptyEnumerable = Enumerable.Empty<SLEntity>();

        public abstract IEnumerator<SLEntity> GetEnumerator();

        IEnumerator IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }

        public SLEntity this[SLEntity attributeKey]
        {
            get
            {
                if (attributeKey.IsNullOrFalse())
                {
                    SLLog.Warn($"attributeKey shouldn't null obj {ToString()}, {ID}");
#if SERVER && LOCALTEST
                    throw new Exception();
#endif
                    return Empty;
                }

                return this[attributeKey.ToString()];
            }
            set
            {
                if (attributeKey.IsNullOrFalse())
                {
                    SLLog.Warn($"attributeKey shouldn't null obj {ToString()}, {ID}");
#if SERVER && LOCALTEST
                    throw new Exception();
#endif
                    return;
                }

                this[attributeKey.ToString()] = value;
            }
        }

        public abstract SLEntity this[string attributeKey]
        {
            get;
            set;
        }

        public abstract SLEntity Clone();

        public abstract SLEntity Link();

        public abstract SLEntity Override();

        public static SLEntity Empty => new SLContainer(null, null, null);

        public static implicit operator double(SLEntity v)
        {
            return v.GetDouble();
        }

        public static implicit operator float(SLEntity v)
        {
            return (float)v.GetDouble();
        }

        public static implicit operator int(SLEntity v)
        {
            return v.GetInt();
        }

        public static implicit operator string(SLEntity v)
        {
            return v.GetString();
        }

        public static implicit operator bool(SLEntity v)
        {
            return v != default(SLEntity) && v.IsExist();
        }

        //public static implicit operator Vector2(SLEntity v)
        //{
        //    return new Vector2(v["X"], v["Y"]);
        //}

        public static bool operator <(SLEntity lhs, SLEntity rhs)
        {
            if (lhs == null && rhs == null)
            {
                return 0 < 0;
            }
            else if (lhs.IsNullOrFalse())
            {
                return 0 < rhs.GetDouble();
            }
            else if (rhs.IsNullOrFalse())
            {
                return lhs.GetDouble() < 0;
            }
            else
            {
                return lhs.GetDouble() < rhs.GetDouble();
            }
        }

        public static bool operator >(SLEntity lhs, SLEntity rhs)
        {
            if (lhs == null && rhs == null)
            {
                return 0 > 0;
            }
            else if (lhs.IsNullOrFalse())
            {
                return 0 > rhs.GetDouble();
            }
            else if (rhs.IsNullOrFalse())
            {
                return lhs.GetDouble() > 0;
            }

            return lhs.GetDouble() > rhs.GetDouble();
        }

        public static bool operator <=(SLEntity lhs, SLEntity rhs)
        {
            if (lhs == null && rhs == null)
            {
                return 0 <= 0;
            }
            else if (lhs.IsNullOrFalse())
            {
                return 0 <= rhs.GetDouble();
            }
            else if (rhs.IsNullOrFalse())
            {
                return lhs.GetDouble() <= 0;
            }
            else
            {
                return lhs.GetDouble() <= rhs.GetDouble();
            }
        }

        public static bool operator >=(SLEntity lhs, SLEntity rhs)
        {
            if (lhs == null && rhs == null)
            {
                return 0 >= 0;
            }
            else if (lhs.IsNullOrFalse())
            {
                return 0 >= rhs.GetDouble();
            }
            else if (rhs.IsNullOrFalse())
            {
                return lhs.GetDouble() >= 0;
            }
            else
            {
                return lhs.GetDouble() >= rhs.GetDouble();
            }
        }

        public static SLEntity operator +(SLEntity single)
        {
            return single;
        }

        public static SLEntity operator -(SLEntity single)
        {
            if (single.IsNullOrFalse())
            {
                return 0;
            }

            return -single.GetDouble();
        }

        public static SLEntity operator +(SLEntity lhs, SLEntity rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return rhs;
            }

            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            if (lhs.IsNumeric && rhs.IsNumeric)
                return lhs.GetDouble() + rhs.GetDouble();

            return lhs.ToString() + rhs.ToString();
        }

        public static double operator +(double lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            if (rhs.IsNumeric)
                return lhs + rhs.GetDouble();

            return lhs;
        }

        public static double operator +(SLEntity lhs, double rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return rhs;
            }

            if (lhs.IsNumeric)
                return lhs.GetDouble() + rhs;

            return rhs;
        }

        public static float operator +(float lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            if (rhs.IsNumeric)
                return lhs + (float)rhs.GetDouble();

            return lhs;
        }

        public static float operator +(SLEntity lhs, float rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return rhs;
            }

            if (lhs.IsNumeric)
                return (float)lhs.GetDouble() + rhs;

            return rhs;
        }

        public static int operator +(SLEntity lhs, int rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return rhs;
            }

            if (lhs.IsNumeric)
                return lhs.GetInt() + rhs;

            return rhs;
        }

        public static int operator +(int lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            if (rhs.IsNumeric)
                return lhs + rhs.GetInt();

            return lhs;
        }

        public static SLEntity operator -(SLEntity lhs, SLEntity rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                if (rhs == default(SLEntity)) return 0;
                return -rhs.GetDouble();
            }

            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            return lhs.GetDouble() - rhs.GetDouble();
        }

        public static double operator -(double lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            if (rhs.IsNumeric)
                return lhs - rhs.GetDouble();

            return lhs;
        }

        public static double operator -(SLEntity lhs, double rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return -rhs;
            }

            if (lhs.IsNumeric)
                return lhs.GetDouble() - rhs;

            return -rhs;
        }

        public static float operator -(float lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            if (rhs.IsNumeric)
                return lhs - (float)rhs.GetDouble();

            return lhs;
        }

        public static float operator -(SLEntity lhs, float rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return -rhs;
            }

            if (lhs.IsNumeric)
                return (float)lhs.GetDouble() - rhs;

            return -rhs;
        }

        public static int operator -(SLEntity lhs, int rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return -rhs;
            }

            if (lhs.IsNumeric)
                return lhs.GetInt() - rhs;

            return rhs;
        }

        public static int operator -(int lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return lhs;
            }

            if (rhs.IsNumeric)
                return lhs - rhs.GetInt();

            return lhs;
        }

        public static SLEntity operator *(SLEntity lhs, SLEntity rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs.IsNullOrFalse())
            {
                return 0;
            }

            if (lhs.IsNumeric && rhs.IsNumeric)
                return lhs.GetDouble() * rhs.GetDouble();

            return 0;
        }

        public static double operator *(double lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs.IsNumeric)
                return lhs * rhs.GetDouble();

            return 0;
        }

        public static double operator *(SLEntity lhs, double rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (lhs.IsNumeric)
                return lhs.GetDouble() * rhs;

            return 0;
        }

        public static float operator *(float lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs.IsNumeric)
                return lhs * (float)rhs.GetDouble();

            return 0;
        }

        public static float operator *(SLEntity lhs, float rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (lhs.IsNumeric)
                return (float)lhs.GetDouble() * rhs;

            return 0;
        }

        public static int operator *(SLEntity lhs, int rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (lhs.IsNumeric)
                return lhs.GetInt() * rhs;

            return 0;
        }

        public static int operator *(int lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs.IsNumeric)
                return lhs * rhs.GetInt();

            return 0;
        }

        public static SLEntity operator /(SLEntity lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                SLLog.Warn($"Divide by 0 {lhs?.GetDouble() ?? 0} / 0");

                if (lhs.IsNullOrFalse()) return 0;
                else return Math.Sign(lhs.GetDouble()) * double.PositiveInfinity;
            }

            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs.IsNumeric == false || rhs == 0.0)
            {
                SLLog.Warn($"Divide by 0 {lhs.GetDouble()} / 0");
                return Math.Sign(lhs.GetDouble()) * double.PositiveInfinity;
            }

            return lhs.GetDouble() / rhs.GetDouble();
        }

        public static double operator /(double lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return Math.Sign(lhs) * double.PositiveInfinity;
            }

            if (rhs.IsNumeric == false || rhs == 0.0)
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return Math.Sign(lhs) * double.PositiveInfinity;
            }

            return lhs / rhs.GetDouble();
        }

        public static double operator /(SLEntity lhs, double rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs == 0.0)
            {
                SLLog.Warn($"Divide by 0 {lhs.GetDouble()} / 0");
                return Math.Sign(lhs.GetDouble()) * double.PositiveInfinity;
            }

            return lhs.GetDouble() / rhs;
        }

        public static float operator /(float lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return Math.Sign(lhs) * float.PositiveInfinity;
            }

            if (rhs.IsNumeric == false || rhs == 0.0)
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return Math.Sign(lhs) * float.PositiveInfinity;
            }

            return lhs / (float)rhs.GetDouble();
        }

        public static float operator /(SLEntity lhs, float rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs == 0.0)
            {
                SLLog.Warn($"Divide by 0 {lhs.GetDouble()} / 0");
                return Math.Sign(lhs.GetDouble()) * float.PositiveInfinity;
            }

            return (float)lhs.GetDouble() / rhs;
        }

        public static int operator /(int lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse())
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return lhs > 0 ? int.MaxValue : int.MinValue;
            }

            if (rhs.IsNumeric == false || rhs == 0.0)
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return lhs > 0 ? int.MaxValue : int.MinValue;
            }

            return lhs / rhs.GetInt();
        }

        public static int operator /(SLEntity lhs, int rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs == 0)
            {
                SLLog.Warn($"Divide by 0 {lhs.GetInt()} / 0");
                return lhs.GetInt() > 0 ? int.MaxValue : int.MinValue;
            }

            return lhs.GetInt() / rhs;
        }

        public static int operator %(SLEntity lhs, SLEntity rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs.IsNullOrFalse())
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return lhs;
            }

            return lhs.GetInt() % rhs.GetInt();
        }

        public static int operator %(SLEntity lhs, int rhs)
        {
            if (lhs.IsNullOrFalse())
            {
                return 0;
            }

            if (rhs == 0)
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return lhs;
            }

            return lhs.GetInt() % rhs;
        }

        public static int operator %(int lhs, SLEntity rhs)
        {
            if (lhs == 0)
            {
                return 0;
            }

            if (rhs.IsNullOrFalse() || rhs.GetInt() == 0)
            {
                SLLog.Warn($"Divide by 0 {lhs} / 0");
                return lhs;
            }

            return lhs % rhs.GetInt();
        }

        public static bool operator ==(SLEntity lhs, bool rhs)
        {
            if (lhs.IsNullOrFalse()) return !rhs;
            else return lhs.IsExist() == rhs;
        }

        public static bool operator !=(SLEntity lhs, bool rhs)
        {
            return !(lhs == rhs);
        }

        public static bool operator ==(bool lhs, SLEntity rhs)
        {
            if (rhs.IsNullOrFalse()) return !lhs;
            else return rhs.IsExist() == rhs;
        }

        public static bool operator !=(bool lhs, SLEntity rhs)
        {
            return !(rhs == lhs);
        }

        //public static bool operator ==(SLEntity lhs, string rhs)
        //{
        //    return (string)lhs == rhs;
        //}

        //public static bool operator !=(SLEntity lhs, string rhs)
        //{
        //    return !(lhs == rhs);
        //}

        //public static bool operator ==(string lhs, SLEntity rhs)
        //{
        //    return rhs == lhs;
        //}

        //public static bool operator !=(string lhs, SLEntity rhs)
        //{
        //    return !(rhs == lhs);
        //}

        public static bool operator ==(SLEntity lhs, int rhs)
        {
            return lhs.GetInt() == rhs;
        }

        public static bool operator !=(SLEntity lhs, int rhs)
        {
            return !(lhs == rhs);
        }

        public static bool operator ==(int lhs, SLEntity rhs)
        {
            return rhs == lhs;
        }

        public static bool operator !=(int lhs, SLEntity rhs)
        {
            return !(rhs == lhs);
        }

        public static bool operator ==(SLEntity lhs, double rhs)
        {
            return lhs.GetDouble() == rhs;
        }

        public static bool operator !=(SLEntity lhs, double rhs)
        {
            return !(lhs == rhs);
        }

        public static bool operator ==(double lhs, SLEntity rhs)
        {
            return rhs == lhs;
        }

        public static bool operator !=(double lhs, SLEntity rhs)
        {
            return !(rhs == lhs);
        }

        public static bool operator ==(SLEntity lhs, float rhs)
        {
            return lhs.GetDouble() == rhs;
        }

        public static bool operator !=(SLEntity lhs, float rhs)
        {
            return !(lhs == rhs);
        }

        public static bool operator ==(float lhs, SLEntity rhs)
        {
            return rhs == lhs;
        }

        public static bool operator !=(float lhs, SLEntity rhs)
        {
            return !(rhs == lhs);
        }

        //public static bool operator ==(SLEntity lhs, SLVector2 rhs)
        //{
        //    return lhs["X"] == rhs.X && lhs["Y"] == rhs.Y;
        //}

        //public static bool operator !=(SLEntity lhs, SLVector2 rhs)
        //{
        //    return lhs["X"] != rhs.X || lhs["Y"] != rhs.Y;
        //}

        public static bool operator ==(SLEntity lhs, SLEntity rhs)
        {
            if (ReferenceEquals(lhs, rhs))// 동일 객체
            {
                return true;
            }
            else if (lhs is null || lhs.IsExist() == false) // 빈객체
            {
                return rhs is null || rhs.IsExist() == false;
            }
            else if (rhs is null || rhs.IsExist() == false)
            {
                return lhs is null || lhs.IsExist() == false;
            }
            else if (lhs.IsValue && rhs.IsValue) // 값비교
            {
                if (lhs.IsNumeric == false || rhs.IsNumeric == false)
                {
                    return lhs.GetString().Equals(rhs.GetString());
                }
                else
                {
                    return lhs.GetDouble() == rhs.GetDouble();
                }
            }
            else if (lhs.IsValue == false && rhs.IsValue == false) // 리스트
            {
                var lhsCount = lhs.Count();
                var rhsCount = rhs.Count();

                if (lhsCount != rhsCount)
                {
                    return false;
                }

                foreach (var l in lhs)
                {
                    if (rhs.HasChild(l.ID) == false)
                    {
                        return false;
                    }

                    if (l != rhs[l.ID])
                    {
                        return false;
                    }
                }

                return true;
            }

            return false;
        }

        public static bool operator !=(SLEntity lhs, SLEntity rhs)
        {
            return !(lhs == rhs);
        }

        public override bool Equals(object obj)
        {
            if (obj == null)
            {
                return false;
            }

            if ((obj is SLEntity) == false)
            {
                return obj.Equals(GetObj());
            }

            return (obj as SLEntity) == this;
        }

        public override int GetHashCode()
        {
            return GetEntityHashCode();
        }

        public static implicit operator SLEntity(string v)
        {
            if (v == null || v == string.Empty) return Empty;
            else return new SLValueString(v);
        }

        public static implicit operator SLEntity(int v)
        {
            return new SLValueInt(v);
        }

        public static implicit operator SLEntity(double v)
        {
            return new SLValueDouble(v);
        }

        private static SLEntity boolTrue = new SLValueString("True");
        //private static SLEntity boolFalse = new SLContainer(null, null, null);

        public static implicit operator SLEntity(bool v)
        {
            if (v)
            {
                if (boolTrue.ID != null) boolTrue = new SLValueString("True");
                return boolTrue;
            }
            else
            {
                return new SLContainer(null, null, null); // TODO: 성능상 수정 필요
                //if (boolFalse || boolFalse.ID != null) boolFalse = new SLContainer(null, null, null);
                //boolFalse.test = true;
                //return boolFalse;
            }
        }

        //public static implicit operator SLEntity(SLVector2 v)
        //{
        //    var ret = new SLContainer(null);
        //    ret["X"] = v.X;
        //    ret["Y"] = v.Y;
        //    return ret;
        //}

        public override string ToString()
        {
            return GetString();
        }

        public int CompareTo(SLEntity other)
        {
            if (IsValue == false || other.IsValue == false)
            {
                // TODO: 리스트 비교 필요
                return GetHashCode().CompareTo(other.GetHashCode());
            }

            if (IsNumeric && other.IsNumeric)
            {
                return GetDouble().CompareTo(other.GetDouble());
            }

            var thisSTR = GetString();
            var otherSTR = other.GetString();
            return thisSTR.CompareTo(otherSTR);
        }

        internal abstract SLEntity ToChild(SLContainerBase parent, string id);

        internal abstract void Move(SLEntity parent, string id);

        public static bool Changed(SLEntity lhs, SLEntity rhs)
        {
            if (lhs is null && rhs is null) return false;

            if (lhs.IsNullOrFalse()) return rhs;
            if (rhs.IsNullOrFalse()) return lhs;

            if (lhs.IsValue && rhs.IsValue)
            {
                return lhs != rhs;
            }

            return false;
        }
    }
}