using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace POSV.Utils
{
    public interface IKV<T, V>
    {
        bool TryGetValue(T key , out V val);
        int Count();
        IEnumerator<KeyValuePair<T , V>> GetEnumerator();
        void Add(T key , V value);
        T[] Keys();
        bool Remove(T key);
        void Clear();
        V GetValue(T key);
        // safesortedlist only
        //V GetValue(int index);
        //T GetKey(int index);
    }

    public class SafeDictionary<TKey, TValue> : IKV<TKey , TValue>
    {
        private readonly object _Padlock = new object();
        private readonly Dictionary<TKey , TValue> _Dictionary;

        public SafeDictionary(int capacity)
        {
            _Dictionary = new Dictionary<TKey , TValue>(capacity);
        }

        public SafeDictionary()
        {
            _Dictionary = new Dictionary<TKey , TValue>();
        }

        public bool TryGetValue(TKey key , out TValue value)
        {
            lock (_Padlock)
                return _Dictionary.TryGetValue(key , out value);
        }

        public TValue this[TKey key]
        {
            get
            {
                lock (_Padlock)
                    return _Dictionary[key];
            }
            set
            {
                lock (_Padlock)
                    _Dictionary[key] = value;
            }
        }

        public int Count()
        {
            lock (_Padlock) return _Dictionary.Count;
        }

        public IEnumerator<KeyValuePair<TKey , TValue>> GetEnumerator()
        {
            return ((ICollection<KeyValuePair<TKey , TValue>>)_Dictionary).GetEnumerator();
        }

        public void Add(TKey key , TValue value)
        {
            lock (_Padlock)
            {
                if (_Dictionary.ContainsKey(key) == false)
                    _Dictionary.Add(key , value);
                else
                    _Dictionary[key] = value;
            }
        }

        public TKey[] Keys()
        {
            lock (_Padlock)
            {
                TKey[] keys = new TKey[_Dictionary.Keys.Count];
                _Dictionary.Keys.CopyTo(keys , 0);
                return keys;
            }
        }

        public bool Remove(TKey key)
        {
            if (key == null)
                return true;
            lock (_Padlock)
            {
                return _Dictionary.Remove(key);
            }
        }

        public void Clear()
        {
            lock (_Padlock)
                _Dictionary.Clear();
        }

        public TValue GetValue(TKey key)
        {
            lock (_Padlock)
                return _Dictionary[key];
        }
    }

    public class SafeSortedList<T, V> : IKV<T , V>
    {
        private object _padlock = new object();
        SortedList<T , V> _list = new SortedList<T , V>();

        public int Count()
        {
            lock (_padlock) return _list.Count;
        }

        public void Add(T key , V val)
        {
            lock (_padlock)
            {
                if (_list.ContainsKey(key) == false)
                    _list.Add(key , val);
                else
                    _list[key] = val;
            }
        }

        public bool Remove(T key)
        {
            if (key == null)
                return true;
            lock (_padlock)
                return _list.Remove(key);
        }

        public T GetKey(int index)
        {
            lock (_padlock) return _list.Keys[index];
        }

        public V GetValue(int index)
        {
            lock (_padlock) return _list.Values[index];
        }

        public T[] Keys()
        {
            lock (_padlock)
            {
                T[] keys = new T[_list.Keys.Count];
                _list.Keys.CopyTo(keys , 0);
                return keys;
            }
        }

        public IEnumerator<KeyValuePair<T , V>> GetEnumerator()
        {
            return ((ICollection<KeyValuePair<T , V>>)_list).GetEnumerator();
        }

        public bool TryGetValue(T key , out V value)
        {
            lock (_padlock)
                return _list.TryGetValue(key , out value);
        }

        public void Clear()
        {
            lock (_padlock)
                _list.Clear();
        }

        public V GetValue(T key)
        {
            lock (_padlock)
                return _list[key];
        }
    }

}