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

namespace IStation.Untity
{
    /// <summary>
    /// 树节点标识辅助类
    /// </summary>
    public class TreeParentIdsHelper
    {
        /// <summary>
        /// 分隔符
        /// </summary>
        public const string Separator = ",";

        /// <summary>
        /// To 列表
        /// </summary>
        public static List<long> ToList(string parentIds)
        {
            if (string.IsNullOrEmpty(parentIds))
                return new List<long>();
            var list = parentIds.Split(new string[] { Separator }, StringSplitOptions.RemoveEmptyEntries);
            return list.Select(x => long.Parse(x)).ToList();
        }

        /// <summary>
        /// To 字符串
        /// </summary>
        public static string ToString(List<long> parentIds)
        {
            if (parentIds == null || parentIds.Count < 1)
                return string.Empty;
            var sb = new StringBuilder();
            sb.Append(Separator);
            foreach (var item in parentIds)
            {
                sb.Append(item.ToString());
                sb.Append(Separator);
            }
            return sb.ToString();
        }

        /// <summary>
        /// 获取子节点的ParentIds
        /// </summary>
        public static string GetChildParentIds(long CurrentID, string CurrentParentIds)
        {
            if (string.IsNullOrEmpty(CurrentParentIds))
                CurrentParentIds = Separator;
            return string.Format("{0}{1}{2}", CurrentParentIds, CurrentID, Separator);
        }

        /// <summary>
        /// 获取父节点ID
        /// </summary>
        public static long GetLastParentID(string ParentIds)
        {
            if (string.IsNullOrEmpty(ParentIds))
                return 0;
            var ids = ParentIds.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries);
            return Convert.ToInt64(ids.Last());
        }

        /// <summary>
        /// 获取子节点的ParentIds
        /// </summary>
        public static List<long> GetChildParentIds(long CurrentID, List<long> CurrentParentIds)
        {
            var parentIds = CurrentParentIds?.ToList();
            if (parentIds == null)
                parentIds = new List<long>();
            parentIds.Add(CurrentID);
            return parentIds;
        }

        /// <summary>
        /// 获取父节点ID
        /// </summary>
        public static long GetLastParentID(List<long> ParentIds)
        {
            if (ParentIds == null || ParentIds.Count < 1)
                return 0; 
            return ParentIds.Last();
        }

    }
}