using System;
using System.Collections.Generic;

namespace FF8
{
    /// <summary>
    /// class to add function to dictionary
    /// </summary>
    /// <see cref="https://stackoverflow.com/questions/22595655/how-to-do-a-dictionary-reverse-lookup"/>
    /// <seealso cref="https://stackoverflow.com/questions/6050633/why-doesnt-dictionary-have-addrange"/>
    public static class DictionaryEx
    {
        #region Methods

        /// <summary>
        /// Reverses Key and Value of dictionary.
        /// </summary>
        /// <typeparam name="TKey"></typeparam>
        /// <typeparam name="TValue"></typeparam>
        /// <param name="source"></param>
        /// <returns></returns>
        public static Dictionary<TValue, TKey> Reverse<TKey, TValue>(this IDictionary<TKey, TValue> source)
        {
            Dictionary<TValue, TKey> dictionary = new Dictionary<TValue, TKey>();
            foreach (KeyValuePair<TKey, TValue> entry in source)
            {
                if (!dictionary.ContainsKey(entry.Value))
                    dictionary.Add(entry.Value, entry.Key);
            }
            return dictionary;
        }

        public static void AddRangeOverride<TKey, TValue>(this Dictionary<TKey, TValue> dic, Dictionary<TKey, TValue> dicToAdd)
        {
            dicToAdd.ForEach(x => dic[x.Key] = x.Value);
        }

        public static void AddRangeNewOnly<TKey, TValue>(this Dictionary<TKey, TValue> dic, Dictionary<TKey, TValue> dicToAdd)
        {
            dicToAdd.ForEach(x => { if (!dic.ContainsKey(x.Key)) dic.Add(x.Key, x.Value); });
        }

        public static void AddRange<TKey, TValue>(this Dictionary<TKey, TValue> dic, Dictionary<TKey, TValue> dicToAdd)
        {
            dicToAdd.ForEach(x => dic.Add(x.Key, x.Value));
        }

        public static bool ContainsKeys<TKey, TValue>(this Dictionary<TKey, TValue> dic, IEnumerable<TKey> keys)
        {
            bool result = false;
            keys.ForEachOrBreak((x) => { result = dic.ContainsKey(x); return result; });
            return result;
        }

        public static void ForEach<T>(this IEnumerable<T> source, Action<T> action)
        {
            foreach (var item in source)
                action(item);
        }

        public static void ForEachOrBreak<T>(this IEnumerable<T> source, Func<T, bool> func)
        {
            foreach (var item in source)
            {
                bool result = func(item);
                if (result) break;
            }
        }

        #endregion Methods
    }
}