// 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.
 
using System.ServiceModel;
using System.Reflection;
 
namespace System.Collections.Generic
{
    [System.Runtime.InteropServices.ComVisible(false)]
    public class SynchronizedCollection<T> : IList<T>, IList
    {
        private List<T> _items;
        private object _sync;
 
        public SynchronizedCollection()
        {
            _items = new List<T>();
            _sync = new Object();
        }
 
        public SynchronizedCollection(object syncRoot)
        {
            if (syncRoot == null)
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentNullException("syncRoot"));
 
            _items = new List<T>();
            _sync = syncRoot;
        }
 
        public SynchronizedCollection(object syncRoot, IEnumerable<T> list)
        {
            if (syncRoot == null)
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentNullException("syncRoot"));
            if (list == null)
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentNullException("list"));
 
            _items = new List<T>(list);
            _sync = syncRoot;
        }
 
        public SynchronizedCollection(object syncRoot, params T[] list)
        {
            if (syncRoot == null)
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentNullException("syncRoot"));
            if (list == null)
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentNullException("list"));
 
            _items = new List<T>(list.Length);
            for (int i = 0; i < list.Length; i++)
                _items.Add(list[i]);
 
            _sync = syncRoot;
        }
 
        public int Count
        {
            get { lock (_sync) { return _items.Count; } }
        }
 
        protected List<T> Items
        {
            get { return _items; }
        }
 
        public object SyncRoot
        {
            get { return _sync; }
        }
 
        public T this[int index]
        {
            get
            {
                lock (_sync)
                {
                    return _items[index];
                }
            }
            set
            {
                lock (_sync)
                {
                    if (index < 0 || index >= _items.Count)
                        throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentOutOfRangeException("index", index,
                                                    string.Format(SRServiceModel.ValueMustBeInRange, 0, _items.Count - 1)));
 
                    this.SetItem(index, value);
                }
            }
        }
 
        public void Add(T item)
        {
            lock (_sync)
            {
                int index = _items.Count;
                this.InsertItem(index, item);
            }
        }
 
        public void Clear()
        {
            lock (_sync)
            {
                this.ClearItems();
            }
        }
 
        public void CopyTo(T[] array, int index)
        {
            lock (_sync)
            {
                _items.CopyTo(array, index);
            }
        }
 
        public bool Contains(T item)
        {
            lock (_sync)
            {
                return _items.Contains(item);
            }
        }
 
        public IEnumerator<T> GetEnumerator()
        {
            lock (_sync)
            {
                return _items.GetEnumerator();
            }
        }
 
        public int IndexOf(T item)
        {
            lock (_sync)
            {
                return this.InternalIndexOf(item);
            }
        }
 
        public void Insert(int index, T item)
        {
            lock (_sync)
            {
                if (index < 0 || index > _items.Count)
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentOutOfRangeException("index", index,
                                                    string.Format(SRServiceModel.ValueMustBeInRange, 0, _items.Count)));
 
                this.InsertItem(index, item);
            }
        }
 
        private int InternalIndexOf(T item)
        {
            int count = _items.Count;
 
            for (int i = 0; i < count; i++)
            {
                if (object.Equals(_items[i], item))
                {
                    return i;
                }
            }
            return -1;
        }
 
        public bool Remove(T item)
        {
            lock (_sync)
            {
                int index = this.InternalIndexOf(item);
                if (index < 0)
                    return false;
 
                this.RemoveItem(index);
                return true;
            }
        }
 
        public void RemoveAt(int index)
        {
            lock (_sync)
            {
                if (index < 0 || index >= _items.Count)
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentOutOfRangeException("index", index,
                                                    string.Format(SRServiceModel.ValueMustBeInRange, 0, _items.Count - 1)));
 
 
                this.RemoveItem(index);
            }
        }
 
        protected virtual void ClearItems()
        {
            _items.Clear();
        }
 
        protected virtual void InsertItem(int index, T item)
        {
            _items.Insert(index, item);
        }
 
        protected virtual void RemoveItem(int index)
        {
            _items.RemoveAt(index);
        }
 
        protected virtual void SetItem(int index, T item)
        {
            _items[index] = item;
        }
 
        bool ICollection<T>.IsReadOnly
        {
            get { return false; }
        }
 
        IEnumerator IEnumerable.GetEnumerator()
        {
            return ((IList)_items).GetEnumerator();
        }
 
        bool ICollection.IsSynchronized
        {
            get { return true; }
        }
 
        object ICollection.SyncRoot
        {
            get { return _sync; }
        }
 
        void ICollection.CopyTo(Array array, int index)
        {
            lock (_sync)
            {
                ((IList)_items).CopyTo(array, index);
            }
        }
 
        object IList.this[int index]
        {
            get
            {
                return this[index];
            }
            set
            {
                VerifyValueType(value);
                this[index] = (T)value;
            }
        }
 
        bool IList.IsReadOnly
        {
            get { return false; }
        }
 
        bool IList.IsFixedSize
        {
            get { return false; }
        }
 
        int IList.Add(object value)
        {
            VerifyValueType(value);
 
            lock (_sync)
            {
                this.Add((T)value);
                return this.Count - 1;
            }
        }
 
        bool IList.Contains(object value)
        {
            VerifyValueType(value);
            return this.Contains((T)value);
        }
 
        int IList.IndexOf(object value)
        {
            VerifyValueType(value);
            return this.IndexOf((T)value);
        }
 
        void IList.Insert(int index, object value)
        {
            VerifyValueType(value);
            this.Insert(index, (T)value);
        }
 
        void IList.Remove(object value)
        {
            VerifyValueType(value);
            this.Remove((T)value);
        }
 
        private static void VerifyValueType(object value)
        {
            if (value == null)
            {
                if (typeof(T).GetTypeInfo().IsValueType)
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentException(SRServiceModel.SynchronizedCollectionWrongTypeNull));
                }
            }
            else if (!(value is T))
            {
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ArgumentException(string.Format(SRServiceModel.SynchronizedCollectionWrongType1, value.GetType().FullName)));
            }
        }
    }
}