// ==++==
// 
//   Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// ==--==
////////////////////////////////////////////////////////////////////////////
//
//  Class:    SortKey
//
//  Purpose:  This class implements a set of methods for retrieving
//            sort key information.
//
//  Date:     August 12, 1998
//
////////////////////////////////////////////////////////////////////////////
 
namespace System.Globalization {
    
    using System;
    using System.Runtime.CompilerServices;
    using System.Runtime.Serialization;
    using System.Diagnostics.Contracts;
 
[System.Runtime.InteropServices.ComVisible(true)]
    [Serializable] public class SortKey
    {
        //--------------------------------------------------------------------//
        //                        Internal Information                        //
        //--------------------------------------------------------------------//
    
        //
        //  Variables.
        //
        // 
 
        [OptionalField(VersionAdded = 3)]
        internal String localeName;       // locale identifier
 
        [OptionalField(VersionAdded = 1)] // LCID field so serialization is Whidbey compatible though we don't officially support it
        internal int win32LCID;           // 
                                          // Whidbey serialization 
 
        internal CompareOptions options;  // options
        internal String m_String;         // original string
        internal byte[] m_KeyData;        // sortkey data
        
#if !FEATURE_PAL
        //
        // The following constructor is designed to be called from CompareInfo to get the 
        // the sort key of specific string for synthetic culture
        //
        internal SortKey(String localeName, String str, CompareOptions options, byte[] keyData)
        {
            this.m_KeyData = keyData;
            this.localeName = localeName;
            this.options    = options;
            this.m_String   = str;
        }
 
#endif // !FEATURE_PAL
 
#if FEATURE_USE_LCID
        //
        // 
 
 
        [OnSerializing]
        private void OnSerializing(StreamingContext context)
        {
            //set LCID to proper value for Whidbey serialization (no other use)
            if (win32LCID == 0)
            {
                win32LCID = CultureInfo.GetCultureInfo(localeName).LCID;
            }
        }
 
        //
        // 
 
 
        [OnDeserialized]
        private void OnDeserialized(StreamingContext context)
        {
            //set locale name to proper value after Whidbey deserialization
            if (String.IsNullOrEmpty(localeName) && win32LCID != 0)
            {
                localeName = CultureInfo.GetCultureInfo(win32LCID).Name;
            }
        }
#endif //FEATURE_USE_LCID
    
        ////////////////////////////////////////////////////////////////////////
        //
        //  GetOriginalString
        //
        //  Returns the original string used to create the current instance
        //  of SortKey.
        //
        ////////////////////////////////////////////////////////////////////////
        public virtual String OriginalString
        {
            get {
                return (m_String);
            }
        }
    
    
        ////////////////////////////////////////////////////////////////////////
        //
        //  GetKeyData
        //
        //  Returns a byte array representing the current instance of the
        //  sort key.
        //
        ////////////////////////////////////////////////////////////////////////
        public virtual byte[] KeyData
        {
            get {
                return (byte[])(m_KeyData.Clone());
            }
        }
    
    
        ////////////////////////////////////////////////////////////////////////
        //
        //  Compare
        //
        //  Compares the two sort keys.  Returns 0 if the two sort keys are
        //  equal, a number less than 0 if sortkey1 is less than sortkey2,
        //  and a number greater than 0 if sortkey1 is greater than sortkey2.
        //
        ////////////////////////////////////////////////////////////////////////
        public static int Compare(SortKey sortkey1, SortKey sortkey2) {
    
            if (sortkey1==null || sortkey2==null) {
                throw new ArgumentNullException((sortkey1==null ? "sortkey1": "sortkey2"));
            }
            Contract.EndContractBlock();
    
            byte[] key1Data = sortkey1.m_KeyData;
            byte[] key2Data = sortkey2.m_KeyData;
    
            Contract.Assert(key1Data!=null, "key1Data!=null");
            Contract.Assert(key2Data!=null, "key2Data!=null");
 
            if (key1Data.Length == 0) {
                if (key2Data.Length == 0) {
                    return (0);
                }
                return (-1);
            }
            if (key2Data.Length == 0) {
                return (1);
            }
    
            int compLen = (key1Data.Length<key2Data.Length)?key1Data.Length:key2Data.Length;
 
            for (int i=0; i<compLen; i++) {
                if (key1Data[i]>key2Data[i]) {
                    return (1);
                }
                if (key1Data[i]<key2Data[i]) {
                    return (-1);
                }
            }
    
            return 0;
    
        }
    
    
        ////////////////////////////////////////////////////////////////////////
        //
        //  Equals
        //
        //  Implements Object.Equals().  Returns a boolean indicating whether
        //  or not object refers to the same SortKey as the current instance.
        //
        ////////////////////////////////////////////////////////////////////////
        public override bool Equals(Object value)
        {
            SortKey that = value as SortKey;
            
            if (that != null)
            {
                return Compare(this, that) == 0;
            }
 
            return (false);
        }
    
    
        ////////////////////////////////////////////////////////////////////////
        //
        //  GetHashCode
        //
        //  Implements Object.GetHashCode().  Returns the hash code for the
        //  SortKey.  The hash code is guaranteed to be the same for
        //  SortKey A and B where A.Equals(B) is true.
        //
        ////////////////////////////////////////////////////////////////////////
        public override int GetHashCode()
        {
            return (CompareInfo.GetCompareInfo(
                this.localeName).GetHashCodeOfString(this.m_String, this.options));
        }
    
    
        ////////////////////////////////////////////////////////////////////////
        //
        //  ToString
        //
        //  Implements Object.ToString().  Returns a string describing the
        //  SortKey.
        //
        ////////////////////////////////////////////////////////////////////////
        public override String ToString()
        {
            return ("SortKey - " + localeName + ", " + options + ", " + m_String);
        }
    }
}