using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using libxmltv.Interfaces;
using System.Runtime.Serialization;
using System.Collections;
using System.Runtime.InteropServices;
using System.Reflection;

namespace libxmltv.Core
{

    public class PropertyCollection<T> : IPropertyCollection<T>
    {
        private List<T> items = new List<T>();
        public PropertyCollection() : this(new List<T>()) { }
        public PropertyCollection(ICollection<T> collection) { foreach (var t in collection) { items.Add(t); } }
        public int PropertyCount { get { return items.Count; } }
        public bool IsReadOnly { get { return (items as ICollection<T>).IsReadOnly; } }
        public void AddProperty(T item) { items.Add(item); }
        public void ClearProperties() { items.Clear(); }
        public bool ContainsProperty(T item) { return items.Contains(item); }
        public void CopyPropertiesTo(T[] array, int arrayIndex) { items.CopyTo(array, arrayIndex); }
        public bool RemoveProperty(T item) { return items.Remove(item); }
        public IEnumerator<T> GetEnumerator() { return items.GetEnumerator(); }
        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { return items.GetEnumerator(); }
    }
    public class PropertyDictionary : PropertyDictionary<string, object> 
    {
        public PropertyDictionary() : base() { }
        public PropertyDictionary(IPropertyDictionary dictionary) : base(dictionary) { }
        public PropertyDictionary(IEqualityComparer<string> comparer) : base(comparer) { }
        public PropertyDictionary(int capacity) :base(capacity) { }
        public PropertyDictionary(IPropertyDictionary dictionary, IEqualityComparer<string> comparer) : base(dictionary, comparer) { }
        public PropertyDictionary(int capacity, IEqualityComparer<string> comparer) : base(capacity, comparer) { }
        protected PropertyDictionary(SerializationInfo info, StreamingContext context) : base(info, context) { }
    }
    public class PropertyDictionary<TKey, TValue> : IPropertyDictionary<TKey, TValue>
    {
        [StructLayout(LayoutKind.Sequential)]
        private struct Entry
        {
            public int hashCode;
            public int next;
            public TKey name;
            public TValue value;
        }
        private Entry[] entries
        {
           get{
               List<Entry> list = new List<Entry>();
               int index = 0;
               foreach (var t in properties)
               {
                   Entry entry = new Entry();
                   entry.hashCode = this.properties.Comparer.GetHashCode(t.Key) & 0x7fffffff;
                   entry.next = index + 1;
                   entry.name = t.Key;
                   entry.value = t.Value;
                   list.Add(entry);
                   index++;
               }
               return list.ToArray();
           }
        }

        private int version
        {
            get
            {
                Type t = typeof(Dictionary<TKey, TValue>);
                var field = t.GetField("version", BindingFlags.NonPublic | BindingFlags.Instance);
                var v = Convert.ToInt32(field.GetValue(properties));
                return v;
            }
        }
        private Dictionary<TKey, TValue> properties;
        public PropertyDictionary() { properties = new Dictionary<TKey, TValue>(); }
        public PropertyDictionary(IPropertyDictionary<TKey, TValue> dictionary) :this() { foreach (var d in dictionary) { properties.Add(d.Name, d.Value); } }
        public PropertyDictionary(IEqualityComparer<TKey> comparer) { properties = new Dictionary<TKey, TValue>(comparer); }
        public PropertyDictionary(int capacity) { properties = new Dictionary<TKey, TValue>(capacity); }
        public PropertyDictionary(IPropertyDictionary<TKey, TValue> dictionary, IEqualityComparer<TKey> comparer) : this(comparer) { foreach (var d in dictionary) { properties.Add(d.Name, d.Value); } }
        public PropertyDictionary(int capacity, IEqualityComparer<TKey> comparer) { properties = new Dictionary<TKey, TValue>(capacity, comparer); }
        protected PropertyDictionary(SerializationInfo info, StreamingContext context) { }
        public IPropertyCollection<TKey> PropertyKeys { get { return new PropertyCollection<TKey>(properties.Keys); } }
        public IPropertyCollection<TValue> PropertyValues { get { return new PropertyCollection<TValue>(properties.Values); } }
        public TValue this[TKey key]
        {
            get
            {
                if (this.ContainsProperty(key))
                {
                    return properties[key];
                }
                else
                {
                    throw new KeyNotFoundException(string.Format("Property '{0}' does not exist.", key));
                }
            }
            set
            {
                if (this.ContainsProperty(key))
                {
                    properties[key] = value;
                }
                else
                {
                    throw new KeyNotFoundException(string.Format("Property '{0}' does not exist.", key));
                }
            }
        }

        public void AddProperty(TKey key, TValue value) { if (properties.ContainsKey(key)) { this[key] = value; } else { properties.Add(key, value); } }
        public bool ContainsProperty(TKey key) { return properties.ContainsKey(key); }
        public bool RemoveProperty(TKey key) { return properties.Remove(key); }
        public bool TryGetPropertyValue(TKey key, out TValue value) { return properties.TryGetValue(key, out value); }
        public int PropertyCount { get { return properties.Count; } }
        public bool IsReadOnly { get { return (properties as ICollection<TKey>).IsReadOnly; } }
        public void AddProperty(PropertyValuePair<TKey, TValue> item) { AddProperty(item.Name, item.Value); }
        public void ClearProperties() { properties.Clear(); }
        public bool ContainsProperty(PropertyValuePair<TKey, TValue> item) { return ContainsProperty(item.Name); }
        public void CopyPropertiesTo(PropertyValuePair<TKey, TValue>[] array, int arrayIndex) 
        {
            var list = properties.ToList().Cast<PropertyValuePair<TKey, TValue>>().ToList();
            list.CopyTo(array, arrayIndex); 
        }
        public bool RemoveProperty(PropertyValuePair<TKey, TValue> item) { return RemoveProperty(item.Name); }
        IEnumerator<PropertyValuePair<TKey, TValue>> IEnumerable<PropertyValuePair<TKey, TValue>>.GetEnumerator() { return new PropertyDictionaryEnumerator(this, 2); }
        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { return properties.GetEnumerator(); }

        #region enumerator support
        public class PropertyDictionaryEnumerator: IEnumerator<PropertyValuePair<TKey,TValue>>, IDisposable
        {
            private PropertyDictionary<TKey, TValue> dictionary;
            private int index;
            private PropertyValuePair<TKey, TValue> current;
            private int getEnumeratorRetType;
            internal const int DictEntry = 1;
            internal const int KeyValuePair = 2;
            private int version;
            public PropertyDictionaryEnumerator(PropertyDictionary<TKey, TValue> dictionary, int getEnumeratorRetType) 
            {
                this.dictionary = dictionary;
                this.version = dictionary.version;
                this.index = 0;
                this.getEnumeratorRetType = getEnumeratorRetType;
                this.current = new PropertyValuePair<TKey, TValue>();
            }

            public PropertyValuePair<TKey, TValue> Current
            {
                get { return this.current; }
            }

            public void Dispose()
            {
            }

            object IEnumerator.Current
            {
                get
                {
                    if ((this.index == 0) || (this.index == (this.dictionary.Count() + 1)))
                    {
                        throw new InvalidOperationException("Operation can't happen");
                    }
                    if (this.getEnumeratorRetType == 1)
                    {
                        return new DictionaryEntry(this.current.Name, this.current.Value);
                    }
                    return new PropertyValuePair<TKey, TValue>(this.current.Name, this.current.Value);
                }
            }

            public bool MoveNext()
            {
                if (this.version != this.dictionary.version)
                {
                    ThrowHelper.ThrowInvalidOperationException(ExceptionResource.InvalidOperation_EnumFailedVersion);
                }
                while (this.index < this.dictionary.Count())
                {
                    if (this.dictionary.entries[this.index].hashCode >= 0)
                    {
                        this.current = new KeyValuePair<TKey, TValue>(this.dictionary.entries[this.index].name, this.dictionary.entries[this.index].value);
                        this.index++;
                        return true;
                    }
                    this.index++;
                }
                this.index = this.dictionary.Count() + 1;
                this.current = new PropertyValuePair<TKey, TValue>();
                return false;
            }
            public void Reset()
            {
                if (this.version != this.dictionary.version)
                {
                    ThrowHelper.ThrowInvalidOperationException(ExceptionResource.InvalidOperation_EnumFailedVersion);
                }
                this.index = 0;
                this.current = new KeyValuePair<TKey, TValue>();
            }
        }
        #endregion   
    }

   
}