using System.Collections.Generic;
using UnityEngine;

public class AnimationDistributor : StateMachineBehaviour
{
    [SerializeField] private float _minSwitchTime = 5;
    [SerializeField] private float _maxSwitchTime = 10;
    [SerializeField] List<string> _triggers;

    [SerializeField] bool _instantSwitch;


    private List<string> _shuffledTriggers;
    private int _currentIndex = 0;
    private float _nextSwitchTime = 0;

    private bool _triggerSetted = false;

    public override void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        _triggerSetted = false;
        if (_instantSwitch)
            _nextSwitchTime = Time.time;
        else
            _nextSwitchTime = Time.time + Random.Range(_minSwitchTime, _maxSwitchTime);
    }

    public override void OnStateUpdate(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        if (Time.time < _nextSwitchTime) return;

        if (_triggerSetted == false)
        {
            animator.SetTrigger(GetNextTrigger());
            _triggerSetted = true;
        }
    }

    public override void OnStateExit(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        _triggerSetted = false;
    }

    private string GetNextTrigger()
    {
        var shuffled = GetShuffledList();
        string trigger = shuffled[_currentIndex];
        _currentIndex++;

        if (_currentIndex >= shuffled.Count)
        {
            _shuffledTriggers = null;
            _currentIndex = 0;
        }

        return trigger;
    }

    private List<string> GetShuffledList()
    {
        if (_shuffledTriggers == null || _shuffledTriggers.Count == 0)
        {
            System.Random rng = new System.Random();
            _shuffledTriggers = new List<string>(_triggers);

            int n = _shuffledTriggers.Count;

            while (n > 1)
            {
                n--;
                int k = rng.Next(n + 1);
                (_shuffledTriggers[k], _shuffledTriggers[n]) = (_shuffledTriggers[n], _shuffledTriggers[k]);
            }
        }

        return _shuffledTriggers;
    }
}