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

public class VehicleSpawner : MonoBehaviour
{
    public List<GameObject> vehiclePrefabs; // 所有可用的车辆预制体
    public Transform[] spawnPoints; // 生成点
    public Vector2 IntervalBetweenWave = new Vector2(6f, 10f); // 生成间隔
    public int minSpawnCount = 1; // 最少生成车辆数
    public int maxSpawnCount = 3; // 最多生成车辆数

    public Vector2 IntervalBetweenVehicle = new Vector2(1f, 3f); // 车辆生成间隔
    public float destroyAfterSeconds = 10f; // 生成多少秒后销毁

    void Start()
    {
        StartCoroutine(SpawnCoroutine()); // 进入循环
    }

    private IEnumerator SpawnCoroutine()
    {
        while (true)
        {
            int spawnCount = Random.Range(minSpawnCount, maxSpawnCount + 1); // 确保包含 maxSpawnCount
            List<GameObject> selectedVehicles = PickUpVehiclesToSpawn(spawnCount); // 选定本轮要生成的车辆

            foreach (GameObject vehiclePrefab in selectedVehicles)
            {
                SpawnVehicle(vehiclePrefab);
                yield return new WaitForSeconds(Random.Range(IntervalBetweenVehicle.x, IntervalBetweenVehicle.y)); // 车辆生成间隔
            }

            yield return new WaitForSeconds(Random.Range(IntervalBetweenWave.x, IntervalBetweenWave.y)); // 等待下一轮生成
        }
    }

    private void SpawnVehicle(GameObject vehiclePrefab)
    {
        Transform spawnPoint = spawnPoints[Random.Range(0, spawnPoints.Length)]; // 随机选择生成点
        GameObject obj = Instantiate(vehiclePrefab, spawnPoint.position, Quaternion.identity, this.transform);

        // 添加按时间销毁组件
        obj.AddComponent<DestroyByTime>().Initialize(destroyAfterSeconds);
    }

    private List<GameObject> PickUpVehiclesToSpawn(int num)
    {
        List<GameObject> availableVehicles = GetAvailableVehicles(); // 获取当前可用的车辆
        List<GameObject> selectedVehicles = new List<GameObject>();

        if (availableVehicles.Count == 0) return selectedVehicles; // 如果没有可用车辆，直接返回空列表

        int spawnCount = Mathf.Min(num, availableVehicles.Count); // 确保不会超过可用车辆数

        for (int i = 0; i < spawnCount; i++)
        {
            int randomIndex = Random.Range(0, availableVehicles.Count);
            selectedVehicles.Add(availableVehicles[randomIndex]);

            // ✅ 立即从列表中移除，确保不会重复选择
            availableVehicles.RemoveAt(randomIndex);
        }

        return selectedVehicles;
    }

    private List<GameObject> GetAvailableVehicles()
    {
        List<GameObject> available = new List<GameObject>(vehiclePrefabs); // 复制所有车辆
        GameObject[] existingVehicles = GameObject.FindGameObjectsWithTag("Vehicle"); // 获取当前场景中的车辆

        // 遍历场景中已经存在的车辆
        foreach (GameObject existing in existingVehicles)
        {
            string existingName = existing.name.Replace("(Clone)", "").Trim();
            available.RemoveAll(c => c.name == existingName);
        }

        return available;
    }
}

public class DestroyByTime : MonoBehaviour
{
    private float lifetime;

    public void Initialize(float seconds)
    {
        lifetime = seconds;
        StartCoroutine(DestroyAfterTime());
    }

    private IEnumerator DestroyAfterTime()
    {
        yield return new WaitForSeconds(lifetime);
        Destroy(gameObject);
    }
}