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

namespace GFGGame
{
    public class Selection<K, T> where K : IComparable<K>
    {
        public K Min { get; set; }
        public K Max { get; set; }
        public T Value { get; set; }
        private readonly SelectionModel model;

        public Selection(K min, K max, T value, SelectionModel model = SelectionModel.Right)
        {
            Min = min;
            Max = max;
            Value = value;
            this.model = model;
        }

        public bool CheckInclude(K checkKey)
        {
            switch (model)
            {
                case SelectionModel.Right:
                    return Min.CompareTo(checkKey) < 0 && checkKey.CompareTo(Max) <= 0;
                case SelectionModel.Left:
                    return Min.CompareTo(checkKey) <= 0 && checkKey.CompareTo(Max) < 0;
                case SelectionModel.AllInclude:
                    return Min.CompareTo(checkKey) <= 0 && checkKey.CompareTo(Max) <= 0;
                case SelectionModel.AllExclude:
                    return Min.CompareTo(checkKey) < 0 && checkKey.CompareTo(Max) < 0;
                default:
                    return false;
            }
        }

        public enum SelectionModel
        {
            Right, // ( ], 包含右边
            Left, // [ ), 包含左边
            AllInclude, // [], 两端包含
            AllExclude //(), 两端都不包含
        }

        public static List<Selection<K, T>> CreateSelections(List<KeyValuePair<K, T>> res, K min, K max, T defaultValue)
        {
            List<Selection<K, T>> list = new List<Selection<K, T>>();
            // 添加首区间
            KeyValuePair<K, T> firstRes = res[0];
            list.Add(new Selection<K, T>(min, firstRes.Key, defaultValue, SelectionModel.Left));

            for (int i = 1; i < res.Count - 1; i++)
            {
                list.Add(new Selection<K, T>(res[i - 1].Key, res[i].Key, res[i].Value, SelectionModel.Left));
            }

            KeyValuePair<K, T> lastRes = res[res.Count - 1];
            // 添加尾区间
            list.Add(new Selection<K, T>(lastRes.Key, max, lastRes.Value, SelectionModel.Left));

            return list.OrderBy(x => x.Min).ToList();
        }

        public static List<Selection<K, T>> CreateSelections(List<KeyValuePair<K, T>> res, K max)
        {
            List<Selection<K, T>> list = new List<Selection<K, T>>();
            // 添加首区间
            for (int i = 0; i < res.Count; i++)
            {
                K maxVal = i == res.Count - 1 ? max : res[i + 1].Key;
                list.Add(new Selection<K, T>(res[i].Key, maxVal, res[i].Value, SelectionModel.Left));
            }

            return list.OrderBy(x => x.Min).ToList();
        }
    }
}