FutureMen/Assets/Scripts/Player/PlayerHands.cs

using System.Collections.Generic;
using DragonLi.Core;
using Knife.Effects.SimpleController;
using UnityEngine;

/// <summary>
/// PlayerHands（永远不会空手版）
/// </summary>
public class PlayerHands : MonoBehaviour
{
    [Header("所有武器预制体（0 号为初始武器）")]
    public GameObject[] WeaponsObjects;

    [SerializeField] private Player player;
    public WeaponSelector weaponSelector;
    public int[] Indices;

    private IWeapon[] weapons;

    /// <summary>
    /// 当前已拥有的武器（存数组下标，永远至少包含 0）
    /// </summary>
    private readonly List<int> available = new List<int>();

    /// <summary>
    /// available 列表中的当前位置
    /// </summary>
    private int currentIdx = 0;

    #region Unity

    private void Start()
    {
        int count = WeaponsObjects.Length;
        weapons = new IWeapon[count];

        for (int i = 0; i < count; i++)
        {
            weapons[i] = WeaponsObjects[i].GetComponent<IWeapon>();

            var w = WeaponsObjects[i].GetComponent<Weapon>();
            if (w != null)
                w.weaponId = i + 1;

            WeaponsObjects[i].SetActive(false);
        }

        // 🔒 初始化：永远拥有 0 号武器
        available.Clear();
        available.Add(0);
        currentIdx = 0;
        ActivateWeapon(0);

        Weapon.OnAmmoDepleted += OnAmmoDepleted;

        if (weaponSelector != null)
            weaponSelector.OnSelectedEvent += OnWeaponSelected;
    }

    private void OnDestroy()
    {
        Weapon.OnAmmoDepleted -= OnAmmoDepleted;

        if (weaponSelector != null)
            weaponSelector.OnSelectedEvent -= OnWeaponSelected;

        foreach (var w in weapons)
            if (w != null)
                w.OnFire -= OnFire;
    }

    #endregion

    #region 切换接口（滚轮 / 摇杆 / UI）

    public void SwitchNext()
    {
        if (available.Count <= 1) return;
        int next = (currentIdx + 1) % available.Count;
        SwitchByListIndex(next);
    }

    public void SwitchPrev()
    {
        if (available.Count <= 1) return;
        int prev = (currentIdx - 1 + available.Count) % available.Count;
        SwitchByListIndex(prev);
    }

    public void OnWeaponSelected(int selectorIndex)
    {
        if (Indices == null) return;

        for (int i = 0; i < Indices.Length; i++)
        {
            if (Indices[i] == selectorIndex)
            {
                int listPos = available.IndexOf(i);
                if (listPos >= 0)
                    SwitchByListIndex(listPos);
                return;
            }
        }
    }

    #endregion

    #region 拾取

    public void PickUpAndSwitchTo(int weaponIndex, int ammo)
    {
        weaponIndex -= 1;
        if (weaponIndex <= 0 || weaponIndex >= WeaponsObjects.Length)
            return;

        if (!available.Contains(weaponIndex))
            available.Add(weaponIndex);

        var w = WeaponsObjects[weaponIndex].GetComponent<Weapon>();
        if (w != null)
            w.PickUpWeapon(w.weaponId, ammo);

        SwitchByListIndex(available.IndexOf(weaponIndex));
    }

    #endregion

    #region 核心切换逻辑

    private void SwitchByListIndex(int listIdx)
    {
        if (listIdx < 0 || listIdx >= available.Count)
            return;

        int newIndex = available[listIdx];
        int oldIndex = available[currentIdx];

        if (newIndex == oldIndex)
            return;

        DeactivateWeapon(oldIndex);
        currentIdx = listIdx;
        ActivateWeapon(newIndex);
    }

    private void ActivateWeapon(int index)
    {
        weapons[index].OnFire += OnFire;
        WeaponsObjects[index].SetActive(true);

        var w = WeaponsObjects[index].GetComponent<Weapon>();
        EventDispatcher.TriggerEvent(
            "ChangeWeaponIcon",
            (PlayerWeaponType)index,
            w != null ? w.bulletsLeft : 0
        );
    }

    private void DeactivateWeapon(int index)
    {
        weapons[index].OnFire -= OnFire;
        WeaponsObjects[index].SetActive(false);
    }

    #endregion

    #region 弹尽处理（永远安全）

    private void OnAmmoDepleted(int weaponId)
    {
        int index = weaponId - 1;

        // 🔒 初始武器永不移除
        if (index <= 0)
            return;

        int listPos = available.IndexOf(index);
        if (listPos < 0)
            return;

        bool wasCurrent = (listPos == currentIdx);

        available.RemoveAt(listPos);

        DeactivateWeapon(index);

        if (wasCurrent)
        {
            // 优先切到前一把，否则切 0
            int nextListPos = Mathf.Clamp(listPos - 1, 0, available.Count - 1);
            currentIdx = nextListPos;
            ActivateWeapon(available[currentIdx]);
        }
        else if (listPos < currentIdx)
        {
            currentIdx--;
        }
    }

    #endregion

    #region 后坐力

    private void OnFire(Vector2 recoil)
    {
        player?.ApplyRecoil(recoil);
    }

    #endregion
}