using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System;

namespace Thousandto.Plugins.Common
{
    /// <summary>
    /// 数据类，适配器，用于适配各种数据，这是一个基类
    /// </summary>
    public abstract class ListItemAdapter
    {
        /// <summary>
        /// <缓存的内容， 数据， 返回>， 用于实例化Item
        /// </summary>
        public Func<ItemHolder, object, ItemHolder> Instantiate;

        public virtual void AddData(object obj, object sender = null)
        {

        }

        /// <summary>
        /// 返回数据总个数
        /// </summary>
        /// <returns></returns>
        public virtual int GetCount()
        {
            return 0;
        }

        public virtual List<int> GetIndexs(int channel)
        {
            return null;
        }

        public virtual int GetReverseNextIndex(int index)
        {
            return 0;
        }

        public virtual int GetNextIndex(int index)
        {
            return 0;
        }

        public virtual int GetChannelId(int index)
        {
            return 0;
        }

        /// <summary>
        /// 返回指定序号的数据
        /// </summary>
        /// <param name="index"></param>
        /// <returns></returns>
        public virtual object GetData(int index)
        {
            return null;
        }

        public ItemHolder GetView(int index, ItemHolder holder)
        {
            var count = GetCount();
            if(index >= count)
            {
                return null;
            }

            var data = GetData(index);
            if (data == null)
            {
                return null;
            }
            if (holder == null)
            {
                holder = new ItemHolder();
                holder = Instantiate(null, data);
            }
            else
            {
                holder = Instantiate(holder, data);
            }

            return holder;
        }
    }
}