using System.Collections.Generic;
using UnityEngine;

namespace Gameplay
{


    public static class ArrayEx
    {

        public static List<T> RandomArrayFromArray<T>(List<T> list,
            int count)
        {
            if (list.Count < count)
            {
                throw new System.Exception("传入list长度不足");
            }
            var cloneList = new List<T>(list);
            var result = new List<T>();
            for (var i = 0; i < count; ++i)
            {
                var index = Random.Range(0, cloneList.Count);
                result.Add(cloneList[index]);
                cloneList.RemoveAt(index);
            }
            return result;
        }

        public static T RandomFromArray<T>(List<T> list)
        {
            var randomIndex = Random.Range(0, list.Count);
            return list[randomIndex];
        }

        public static T RandomFromArray<T>(T[] list)
        {
            var randomIndex = Random.Range(0, list.Length);
            return list[randomIndex];
        }

        public static T RandomWithWeights<T>(List<T> list,
            List<int> weights)
        {
            var totalWeight = 0;
            for (var i = 0; i < weights.Count; ++i)
            {
                totalWeight += weights[i];
            }
            var randomValue = Random.Range(0, totalWeight);
            var currentWeight = 0;
            for (var i = 0; i < weights.Count; ++i)
            {
                currentWeight += weights[i];
                if (randomValue < currentWeight)
                {
                    return list[i];
                }
            }
            return list[^1];
        }


    }
}