/DLR_Main/Languages/IronPython/IronPython/Runtime/PythonTuple.cs

/* ****************************************************************************

 *

 * Copyright (c) Microsoft Corporation. 

 *

 * This source code is subject to terms and conditions of the Apache License, Version 2.0. A 

 * copy of the license can be found in the License.html file at the root of this distribution. If 

 * you cannot locate the  Apache License, Version 2.0, please send an email to 

 * dlr@microsoft.com. By using this source code in any fashion, you are agreeing to be bound 

 * by the terms of the Apache License, Version 2.0.

 *

 * You must not remove this notice, or any other, from this software.

 *

 *

 * ***************************************************************************/



using System;

using System.Collections;

using System.Collections.Generic;

using System.Diagnostics;

using System.Runtime.InteropServices;

using System.Text;



using Microsoft.Scripting;

using Microsoft.Scripting.Runtime;

using Microsoft.Scripting.Utils;



using IronPython.Runtime.Exceptions;

using IronPython.Runtime.Operations;

using IronPython.Runtime.Types;



#if CLR2

using Microsoft.Scripting.Math;

#else

using System.Numerics;

#endif



namespace IronPython.Runtime {

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1710:IdentifiersShouldHaveCorrectSuffix")]

    [PythonType("tuple"), Serializable, DebuggerTypeProxy(typeof(CollectionDebugProxy)), DebuggerDisplay("tuple, {Count} items")]

    public class PythonTuple : ICollection, IEnumerable, IEnumerable<object>, IList, IList<object>, ICodeFormattable,

#if CLR2

        IValueEquality,

#endif

        IStructuralEquatable, IStructuralComparable

    {

        internal readonly object[] _data;

        

        internal static readonly PythonTuple EMPTY = new PythonTuple();



        public PythonTuple(object o) {

            this._data = MakeItems(o);

        }



        protected PythonTuple(object[] items) {

            this._data = items;

        }



        public PythonTuple() {

            this._data = ArrayUtils.EmptyObjects;

        }



        internal PythonTuple(PythonTuple other, object o) {

            this._data = other.Expand(o);

        }



        #region Python Constructors



        // Tuples are immutable so their initialization happens in __new__

        // They also explicitly implement __new__ so they can perform the

        // appropriate caching.  



        public static PythonTuple __new__(CodeContext context, PythonType cls) {

            if (cls == TypeCache.PythonTuple) {

                return EMPTY;

            } else {

                PythonTuple tupObj = cls.CreateInstance(context) as PythonTuple;

                if (tupObj == null) throw PythonOps.TypeError("{0} is not a subclass of tuple", cls);

                return tupObj;

            }

        }



        public static PythonTuple __new__(CodeContext context, PythonType cls, object sequence) {

            if (sequence == null) throw PythonOps.TypeError("iteration over a non-sequence");



            if (cls == TypeCache.PythonTuple) {

                if (sequence.GetType() == typeof(PythonTuple)) return (PythonTuple)sequence;

                return new PythonTuple(MakeItems(sequence));

            } else {

                PythonTuple tupObj = cls.CreateInstance(context, sequence) as PythonTuple;

                if (tupObj == null) throw PythonOps.TypeError("{0} is not a subclass of tuple", cls);

                return tupObj;

            }

        }

        #endregion



        #region Python 2.6 Methods



        public int index(object obj, object start) {

            return index(obj, Converter.ConvertToIndex(start), _data.Length);

        }



        public int index(object obj, [DefaultParameterValue(0)]int start) {

            return index(obj, start, _data.Length);

        }



        public int index(object obj, object start, object end) {

            return index(obj, Converter.ConvertToIndex(start), Converter.ConvertToIndex(end));

        }



        public int index(object obj, int start, int end) {

            start = PythonOps.FixSliceIndex(start, _data.Length);

            end = PythonOps.FixSliceIndex(end, _data.Length);



            for (int i = start; i < end; i++) {

                if (PythonOps.EqualRetBool(obj, _data[i])) {

                    return i;

                }

            }



            throw PythonOps.ValueError("tuple.index(x): x not in list");

        }



        public int count(object obj) {

            int cnt = 0;

            foreach (object elem in _data) {

                if (PythonOps.EqualRetBool(obj, elem)) {

                    cnt++;

                }

            }

            return cnt;

        }



        #endregion



        internal static PythonTuple Make(object o) {

            if (o is PythonTuple) return (PythonTuple)o;

            return new PythonTuple(MakeItems(o));

        }



        internal static PythonTuple MakeTuple(params object[] items) {

            if (items.Length == 0) return EMPTY;

            return new PythonTuple(items);

        }



        private static object[] MakeItems(object o) {

            object[] arr;

            if (o is PythonTuple) {

                return ((PythonTuple)o)._data;

            } else if (o is string) {

                string s = (string)o;

                object[] res = new object[s.Length];

                for (int i = 0; i < res.Length; i++) {

                    res[i] = ScriptingRuntimeHelpers.CharToString(s[i]);

                }

                return res;

            } else if (o is List) {

                return ((List)o).GetObjectArray();

            } else if ((arr = o as object[])!=null) {

                return ArrayOps.CopyArray(arr, arr.Length);

            } else {

                PerfTrack.NoteEvent(PerfTrack.Categories.OverAllocate, "TupleOA: " + PythonTypeOps.GetName(o));



                List<object> l = new List<object>();

                IEnumerator i = PythonOps.GetEnumerator(o);

                while (i.MoveNext()) {

                    l.Add(i.Current);

                }



                return l.ToArray();

            }

        }

        

        /// <summary>

        /// Return a copy of this tuple's data array.

        /// </summary>

        internal object[] ToArray() {

            return ArrayOps.CopyArray(_data, _data.Length);

        }



        #region ISequence Members



        public virtual int __len__() {

            return _data.Length;

        }



        public virtual object this[int index] {

            get {

                return _data[PythonOps.FixIndex(index, _data.Length)];

            }

        }

        

        public virtual object this[object index] {

            get {

                return this[Converter.ConvertToIndex(index)];

            }

        }



        public virtual object this[BigInteger index] {

            get {

                return this[(int)index];

            }

        }



        public virtual object __getslice__(int start, int stop) {

            Slice.FixSliceArguments(_data.Length, ref start, ref stop);



            if (start == 0 && stop == _data.Length &&

                this.GetType() == typeof(PythonTuple)) {

                return this;

            }

            return MakeTuple(ArrayOps.GetSlice(_data, start, stop));

        }



        public virtual object this[Slice slice] {

            get {

                int start, stop, step;

                slice.indices(_data.Length, out start, out stop, out step);



                if (start == 0 && stop == _data.Length && step == 1 &&

                    this.GetType() == typeof(PythonTuple)) {

                    return this;

                }

                return MakeTuple(ArrayOps.GetSlice(_data, start, stop, step));

            }

        }



        #endregion



        #region binary operators

        public static PythonTuple operator +([NotNull]PythonTuple x, [NotNull]PythonTuple y) {

            return MakeTuple(ArrayOps.Add(x._data, x._data.Length, y._data, y._data.Length));

        }



        private static PythonTuple MultiplyWorker(PythonTuple self, int count) {

            if (count <= 0) {

                return EMPTY;

            } else if (count == 1 && self.GetType() == typeof(PythonTuple)) {

                return self;

            }



            return MakeTuple(ArrayOps.Multiply(self._data, self._data.Length, count));

        }



        public static PythonTuple operator *(PythonTuple x, int n) {

            return MultiplyWorker(x, n);

        }



        public static PythonTuple operator *(int n, PythonTuple x) {

            return MultiplyWorker(x, n);

        }



        public static object operator *([NotNull]PythonTuple self, [NotNull]Index count) {

            return PythonOps.MultiplySequence<PythonTuple>(MultiplyWorker, self, count, true);

        }



        public static object operator *([NotNull]Index count, [NotNull]PythonTuple self) {

            return PythonOps.MultiplySequence<PythonTuple>(MultiplyWorker, self, count, false);

        }



        public static object operator *([NotNull]PythonTuple self, object count) {

            int index;

            if (Converter.TryConvertToIndex(count, out index)) {

                return self * index;

            }

            throw PythonOps.TypeErrorForUnIndexableObject(count);

        }



        public static object operator *(object count, [NotNull]PythonTuple self) {

            int index;

            if (Converter.TryConvertToIndex(count, out index)) {

                return index * self;

            }



            throw PythonOps.TypeErrorForUnIndexableObject(count);

        }



        #endregion



        #region ICollection Members



        bool ICollection.IsSynchronized {

            get { return false; }

        }



        public int Count {

            [PythonHidden]

            get { return _data.Length; }

        }



        [PythonHidden]

        public void CopyTo(Array array, int index) {

            Array.Copy(_data, 0, array, index, _data.Length);

        }



        object ICollection.SyncRoot {

            get {

                return this;

            }

        }



        #endregion



        public virtual IEnumerator __iter__() {

            return new TupleEnumerator(this);

        }



        #region IEnumerable Members



        [PythonHidden]

        public IEnumerator GetEnumerator() {

            return __iter__();

        }



        #endregion



        private object[] Expand(object value) {

            object[] args;

            int length = _data.Length;

            if (value == null)

                args = new object[length];

            else

                args = new object[length + 1];



            for (int i = 0; i < length; i++) {

                args[i] = _data[i];

            }



            if (value != null) {

                args[length] = value;

            }



            return args;

        }



        public object __getnewargs__() {

            // Call "new Tuple()" to force result to be a Tuple (otherwise, it could possibly be a Tuple subclass)

            return PythonTuple.MakeTuple(new PythonTuple(this));

        }



        #region IEnumerable<object> Members



        IEnumerator<object> IEnumerable<object>.GetEnumerator() {

            return new TupleEnumerator(this);

        }



        #endregion



        #region IList<object> Members



        [PythonHidden]

        public int IndexOf(object item) {

            for (int i = 0; i < Count; i++) {

                if (PythonOps.EqualRetBool(this[i], item)) return i;

            }

            return -1;

        }



        void IList<object>.Insert(int index, object item) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        void IList<object>.RemoveAt(int index) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        object IList<object>.this[int index] {

            get {

                return this[index];

            }

            set {

                throw new InvalidOperationException("Tuple is readonly");

            }

        }



        #endregion



        #region ICollection<object> Members



        void ICollection<object>.Add(object item) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        void ICollection<object>.Clear() {

            throw new InvalidOperationException("Tuple is readonly");

        }



        [PythonHidden]

        public bool Contains(object item) {

            for (int i = 0; i < _data.Length; i++) {

                if (PythonOps.EqualRetBool(_data[i], item)) {

                    return true;

                }

            }



            return false;

        }



        [PythonHidden]

        public void CopyTo(object[] array, int arrayIndex) {

            for (int i = 0; i < Count; i++) {

                array[arrayIndex + i] = this[i];

            }

        }



        bool ICollection<object>.IsReadOnly {

            get { return true; }

        }



        bool ICollection<object>.Remove(object item) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        #endregion



        #region Rich Comparison Members



        internal int CompareTo(PythonTuple other) {

            return PythonOps.CompareArrays(_data, _data.Length, other._data, other._data.Length);

        }



        public static bool operator >([NotNull]PythonTuple self, [NotNull]PythonTuple other) {

            return self.CompareTo(other) > 0;

        }



        public static bool operator <([NotNull]PythonTuple self, [NotNull]PythonTuple other) {

            return self.CompareTo(other) < 0;

        }



        public static bool operator >=([NotNull]PythonTuple self, [NotNull]PythonTuple other) {

            return self.CompareTo(other) >= 0;

        }



        public static bool operator <=([NotNull]PythonTuple self, [NotNull]PythonTuple other) {

            return self.CompareTo(other) <= 0;

        }



        #endregion



        #region IStructuralComparable Members



        int IStructuralComparable.CompareTo(object obj, IComparer comparer) {

            PythonTuple other = obj as PythonTuple;

            if (other == null) {

                throw new ValueErrorException("expected tuple");

            }



            return PythonOps.CompareArrays(_data, _data.Length, other._data, other._data.Length, comparer);

        }



        #endregion



        public override bool Equals(object obj) {

            if (!Object.ReferenceEquals(this, obj)) {

                PythonTuple other = obj as PythonTuple;

                if (other == null || _data.Length != other._data.Length) {

                    return false;

                }



                for (int i = 0; i < _data.Length; i++) {

                    object obj1 = this[i], obj2 = other[i];



                    if (Object.ReferenceEquals(obj1, obj2)) {

                        continue;

                    } else if (obj1 != null) {

                        if (!obj1.Equals(obj2)) {

                            return false;

                        }

                    } else {

                        return false;

                    }

                }

            }

            return true;

        }



        public override int GetHashCode() {

            int hash1 = 6551;

            int hash2 = hash1;



            for (int i = 0; i < _data.Length; i += 2) {

                hash1 = ((hash1 << 27) + ((hash2 + 1) << 1) + (hash1 >> 5)) ^ _data[i].GetHashCode();



                if (i == _data.Length - 1) {

                    break;

                }

                hash2 = ((hash2 << 5) + ((hash1 - 1) >> 1) + (hash2 >> 27)) ^ _data[i + 1].GetHashCode();

            }

            return hash1 + (hash2 * 1566083941);

        }



        private int GetHashCode(HashDelegate dlg) {

            int hash1 = 6551;

            int hash2 = hash1;



            for (int i = 0; i < _data.Length; i += 2) {

                hash1 = ((hash1 << 27) + ((hash2 + 1) << 1) + (hash1 >> 5)) ^ dlg(_data[i], ref dlg);



                if (i == _data.Length - 1) {

                    break;

                }

                hash2 = ((hash2 << 5) + ((hash1 - 1) >> 1) + (hash2 >> 27)) ^ dlg(_data[i + 1], ref dlg);

            }

            return hash1 + (hash2 * 1566083941);

        }



        private int GetHashCode(IEqualityComparer comparer) {

            int hash1 = 6551;

            int hash2 = hash1;



            for (int i = 0; i < _data.Length; i += 2) {

                hash1 = ((hash1 << 27) + ((hash2 + 1) << 1) + (hash1 >> 5)) ^ comparer.GetHashCode(_data[i]);



                if (i == _data.Length - 1) {

                    break;

                }

                hash2 = ((hash2 << 5) + ((hash1 - 1) >> 1) + (hash2 >> 27)) ^ comparer.GetHashCode(_data[i + 1]);

            }

            return hash1 + (hash2 * 1566083941);

        }



        public override string ToString() {

            return __repr__(DefaultContext.Default);

        }



        #region IValueEquality Members

#if CLR2

        int IValueEquality.GetValueHashCode() {

            return GetHashCode(DefaultContext.DefaultPythonContext.InitialHasher);

        }



        bool IValueEquality.ValueEquals(object other) {

            if (!Object.ReferenceEquals(other, this)) {

                PythonTuple l = other as PythonTuple;

                if (l == null || _data.Length != l._data.Length) {

                    return false;

                }



                for (int i = 0; i < _data.Length; i++) {

                    object obj1 = _data[i], obj2 = l._data[i];



                    if (Object.ReferenceEquals(obj1, obj2)) {

                        continue;

                    } else if (!PythonOps.EqualRetBool(obj1, obj2)) {

                        return false;

                    }

                }

            }

            return true;

        }

#endif

        #endregion



        #region IStructuralEquatable Members



        int IStructuralEquatable.GetHashCode(IEqualityComparer comparer) {

            // Optimization for when comparer is IronPython's default IEqualityComparer

            PythonContext.PythonEqualityComparer pythonComparer = comparer as PythonContext.PythonEqualityComparer;

            if (pythonComparer != null) {

                return GetHashCode(pythonComparer.Context.InitialHasher);

            }



            return GetHashCode(comparer);

        }



        bool IStructuralEquatable.Equals(object other, IEqualityComparer comparer) {

            if (!Object.ReferenceEquals(other, this)) {

                PythonTuple l = other as PythonTuple;

                if (l == null || _data.Length != l._data.Length) {

                    return false;

                }



                for (int i = 0; i < _data.Length; i++) {

                    object obj1 = _data[i], obj2 = l._data[i];



                    if (Object.ReferenceEquals(obj1, obj2)) {

                        continue;

                    } else if (!comparer.Equals(obj1, obj2)) {

                        return false;

                    }

                }

            }

            return true;

        }



        #endregion



        #region ICodeFormattable Members



        public virtual string/*!*/ __repr__(CodeContext/*!*/ context) {

            StringBuilder buf = new StringBuilder();

            buf.Append("(");

            for (int i = 0; i < _data.Length; i++) {

                if (i > 0) buf.Append(", ");

                buf.Append(PythonOps.Repr(context, _data[i]));

            }

            if (_data.Length == 1) buf.Append(",");

            buf.Append(")");

            return buf.ToString();

        }



        #endregion



        #region IList Members



        int IList.Add(object value) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        void IList.Clear() {

            throw new InvalidOperationException("Tuple is readonly");

        }



        void IList.Insert(int index, object value) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        bool IList.IsFixedSize {

            get { return true; }

        }



        bool IList.IsReadOnly {

            get { return true; }

        }



        void IList.Remove(object value) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        void IList.RemoveAt(int index) {

            throw new InvalidOperationException("Tuple is readonly");

        }



        object IList.this[int index] {

            get {

                return this[index];

            }

            set {

                throw new InvalidOperationException("Tuple is readonly");

            }

        }



        #endregion

    }



    /// <summary>

    /// public class to get optimized

    /// </summary>

    [PythonType("tupleiterator")]

    public sealed class TupleEnumerator : IEnumerable, IEnumerator, IEnumerator<object> {

        private int _curIndex;

        private PythonTuple _tuple;



        public TupleEnumerator(PythonTuple t) {

            _tuple = t;

            _curIndex = -1;

        }



        #region IEnumerator Members



        public object Current {

            get {

                // access _data directly because this is what CPython does:

                // class T(tuple):

                //     def __getitem__(self): return None

                // 

                // for x in T((1,2)): print x

                // prints 1 and 2

                return _tuple._data[_curIndex];

            }

        }



        public bool MoveNext() {

            if ((_curIndex + 1) >= _tuple.Count) {

                return false;

            }

            _curIndex++;

            return true;

        }



        public void Reset() {

            _curIndex = -1;

        }



        #endregion



        #region IDisposable Members



        public void Dispose() {

            GC.SuppressFinalize(this);

        }



        #endregion



        #region IEnumerable Members



        public IEnumerator GetEnumerator() {

            return this;

        }



        #endregion

    }

}