// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

/*============================================================
**
**
**
** Purpose: This class will encapsulate a long and provide an
**          Object representation of it.
**
** 
===========================================================*/
namespace System {
    
    using System;
    using System.Globalization;
    using System.Runtime.InteropServices;
    using System.Diagnostics.Contracts;

[Serializable]
[System.Runtime.InteropServices.StructLayout(LayoutKind.Sequential)]
[System.Runtime.InteropServices.ComVisible(true)]
    public struct Int64 : IComparable, IFormattable, IConvertible
        , IComparable<Int64>, IEquatable<Int64>
    {
        internal long m_value;
    
        public const long MaxValue = 0x7fffffffffffffffL;
        public const long MinValue = unchecked((long)0x8000000000000000L);

        // Compares this object to another object, returning an integer that
        // indicates the relationship. 
        // Returns a value less than zero if this  object
        // null is considered to be less than any instance.
        // If object is not of type Int64, this method throws an ArgumentException.
        // 
        public int CompareTo(Object value) {
            if (value == null) {
                return 1;
            }
            if (value is Int64) {
                // Need to use compare because subtraction will wrap
                // to positive for very large neg numbers, etc.
                long i = (long)value;
                if (m_value < i) return -1;
                if (m_value > i) return 1;
                return 0;
            }
            throw new ArgumentException (Environment.GetResourceString("Arg_MustBeInt64"));
        }

        public int CompareTo(Int64 value) {
            // Need to use compare because subtraction will wrap
            // to positive for very large neg numbers, etc.
            if (m_value < value) return -1;
            if (m_value > value) return 1;
            return 0;
        }
    
        public override bool Equals(Object obj) {
            if (!(obj is Int64)) {
                return false;
            }
            return m_value == ((Int64)obj).m_value;
        }

        [System.Runtime.Versioning.NonVersionable]
        public bool Equals(Int64 obj)
        {
            return m_value == obj;
        }

        // The value of the lower 32 bits XORed with the uppper 32 bits.
        public override int GetHashCode() {
            return (unchecked((int)((long)m_value)) ^ (int)(m_value >> 32));
        }

        public override String ToString() {
            Contract.Ensures(Contract.Result<String>() != null);
            return Number.FormatInt64(m_value, null, NumberFormatInfo.CurrentInfo);
        }
    
        public String ToString(IFormatProvider provider) {
            Contract.Ensures(Contract.Result<String>() != null);
            return Number.FormatInt64(m_value, null, NumberFormatInfo.GetInstance(provider));
        }
    
        public String ToString(String format) {
            Contract.Ensures(Contract.Result<String>() != null);
            return Number.FormatInt64(m_value, format, NumberFormatInfo.CurrentInfo);
        }

        public String ToString(String format, IFormatProvider provider) {
            Contract.Ensures(Contract.Result<String>() != null);
            return Number.FormatInt64(m_value, format, NumberFormatInfo.GetInstance(provider));
        }

        public static long Parse(String s) {
            return Number.ParseInt64(s, NumberStyles.Integer, NumberFormatInfo.CurrentInfo);
        }
    
        public static long Parse(String s, NumberStyles style) {
            NumberFormatInfo.ValidateParseStyleInteger(style);
            return Number.ParseInt64(s, style, NumberFormatInfo.CurrentInfo);
        }

        public static long Parse(String s, IFormatProvider provider) {
            return Number.ParseInt64(s, NumberStyles.Integer, NumberFormatInfo.GetInstance(provider));
        }


        // Parses a long from a String in the given style.  If
        // a NumberFormatInfo isn't specified, the current culture's 
        // NumberFormatInfo is assumed.
        // 
        public static long Parse(String s, NumberStyles style, IFormatProvider provider) {
            NumberFormatInfo.ValidateParseStyleInteger(style);
            return Number.ParseInt64(s, style, NumberFormatInfo.GetInstance(provider));
        }

        public static Boolean TryParse(String s, out Int64 result) {
            return Number.TryParseInt64(s, NumberStyles.Integer, NumberFormatInfo.CurrentInfo, out result);
        }

        public static Boolean TryParse(String s, NumberStyles style, IFormatProvider provider, out Int64 result) {
            NumberFormatInfo.ValidateParseStyleInteger(style);
            return Number.TryParseInt64(s, style, NumberFormatInfo.GetInstance(provider), out result);
        }

        //
        // IConvertible implementation
        // 
        
        public TypeCode GetTypeCode() {
            return TypeCode.Int64;
        }

        /// <internalonly/>
        bool IConvertible.ToBoolean(IFormatProvider provider) {
            return Convert.ToBoolean(m_value);
        }

        /// <internalonly/>
        char IConvertible.ToChar(IFormatProvider provider) {
            return Convert.ToChar(m_value);
        }

        /// <internalonly/>
        sbyte IConvertible.ToSByte(IFormatProvider provider) {
            return Convert.ToSByte(m_value);
        }

        /// <internalonly/>
        byte IConvertible.ToByte(IFormatProvider provider) {
            return Convert.ToByte(m_value);
        }

        /// <internalonly/>
        short IConvertible.ToInt16(IFormatProvider provider) {
            return Convert.ToInt16(m_value);
        }

        /// <internalonly/>
        ushort IConvertible.ToUInt16(IFormatProvider provider) {
            return Convert.ToUInt16(m_value);
        }

        /// <internalonly/>
        int IConvertible.ToInt32(IFormatProvider provider) {
            return Convert.ToInt32(m_value);
        }

        /// <internalonly/>
        uint IConvertible.ToUInt32(IFormatProvider provider) {
            return Convert.ToUInt32(m_value);
        }

        /// <internalonly/>
        long IConvertible.ToInt64(IFormatProvider provider) {
            return m_value;
        }

        /// <internalonly/>
        ulong IConvertible.ToUInt64(IFormatProvider provider) {
            return Convert.ToUInt64(m_value);
        }

        /// <internalonly/>
        float IConvertible.ToSingle(IFormatProvider provider) {
            return Convert.ToSingle(m_value);
        }

        /// <internalonly/>
        double IConvertible.ToDouble(IFormatProvider provider) {
            return Convert.ToDouble(m_value);
        }

        /// <internalonly/>
        Decimal IConvertible.ToDecimal(IFormatProvider provider) {
            return Convert.ToDecimal(m_value);
        }

        /// <internalonly/>
        DateTime IConvertible.ToDateTime(IFormatProvider provider) {
            throw new InvalidCastException(Environment.GetResourceString("InvalidCast_FromTo", "Int64", "DateTime"));
        }

        /// <internalonly/>
        Object IConvertible.ToType(Type type, IFormatProvider provider) {
            return Convert.DefaultToType((IConvertible)this, type, provider);
        }
    }
}