using UnityEngine;

public enum BobberState
{
    LyingDown,     // 躺漂
    RisingUp,      // 起漂
    Standing,      // 正常站立
    Bottom,        // 挂底
    TopLift,       // 顶漂
    DownPull,      // 黑漂
    Nibble         // 小顿口
}

public class FloatBobberControllerProV4 : MonoBehaviour
{
    [Header("Environment")]
    public float waterLevel = 0f;

    [Header("Float Settings")]
    public float floatLength = 0.20f;      // 漂总长度
    public float buoyancyForce = 0.35f;    // 浮力强度
    public float mass = 0.015f;            // 重量
    public float tiltRecoverySpeed = 3f;   // 漂恢复垂直速度
    public float maxTiltAngle = 60f;       // 躺漂最大角度

    [Header("Line Settings")]
    public float lineTension = 0f;         // 动态线张力（由鱼影响）
    public float bottomDrag = 1.5f;        // 铅坠触底时的阻力

    [Header("State Machine")]
    public BobberState state = BobberState.LyingDown;

    // internal vars
    private float verticalSpeed = 0f;
    private float angle = 60f;      // 初始躺漂角度
    private float lastHeight;
    private float deltaY;

    void Start()
    {
        lastHeight = transform.position.y;
        state = BobberState.LyingDown;
    }

    void Update()
    {
        deltaY = transform.position.y - lastHeight;
        lastHeight = transform.position.y;

        ApplyPhysics();
        ProcessStateMachine();
        ApplyRotation();
    }

    // ---------------------------------------------------------------------
    // 一切物理都由状态机控制
    // ---------------------------------------------------------------------
    void ProcessStateMachine()
    {
        switch (state)
        {
            case BobberState.LyingDown:
                LyingDownBehaviour();
                break;

            case BobberState.RisingUp:
                RisingUpBehaviour();
                break;

            case BobberState.Standing:
                StandingBehaviour();
                break;

            case BobberState.Bottom:
                BottomBehaviour();
                break;

            case BobberState.TopLift:
                TopLiftBehaviour();
                break;

            case BobberState.DownPull:
                DownPullBehaviour();
                break;

            case BobberState.Nibble:
                NibbleBehaviour();
                break;
        }

        AutoTransition();
    }

    // ---------------------------------------------------------------------
    // 【状态 → 行为】
    // ---------------------------------------------------------------------

    void LyingDownBehaviour()
    {
        // 浮漂处于平躺，几乎无浮力
        angle = Mathf.Lerp(angle, maxTiltAngle, Time.deltaTime * 1.5f);

        // 水面浮力很小
        verticalSpeed += (buoyancyForce * 0.1f - mass * 9.8f) * Time.deltaTime;
    }

    void RisingUpBehaviour()
    {
        // 浮漂正在被浮力慢慢扶正
        angle = Mathf.Lerp(angle, 0, Time.deltaTime * (tiltRecoverySpeed * 0.7f));

        // 浮力略加强
        verticalSpeed += (buoyancyForce * 0.5f) * Time.deltaTime;
    }

    void StandingBehaviour()
    {
        // 完全立稳
        angle = Mathf.Lerp(angle, 0, Time.deltaTime * tiltRecoverySpeed);

        // 浮力与重力平衡，小幅波动
        verticalSpeed += Mathf.Sin(Time.time * 4f) * 0.001f;
    }

    void BottomBehaviour()
    {
        // 铅坠或饵触底 → 浮漂立不起来
        angle = Mathf.Lerp(angle, 20f, Time.deltaTime * 2f);

        // 上浮被底部拖住
        verticalSpeed *= 0.6f;
    }

    void TopLiftBehaviour()
    {
        // 顶漂 → 漂被往上托一点
        verticalSpeed += 0.02f;
    }

    void DownPullBehaviour()
    {
        // 黑漂 → 往下猛拉
        verticalSpeed -= 0.05f;
    }

    void NibbleBehaviour()
    {
        // 小顿口 → 轻微波动
        verticalSpeed += Mathf.Sin(Time.time * 20f) * 0.0015f;
    }

    // ---------------------------------------------------------------------
    // 状态自动切换
    // ---------------------------------------------------------------------
    void AutoTransition()
    {
        // 1. 浮漂露出 40% 以上 → 起漂或站漂
        float headHeight = transform.position.y + floatLength;

        if (state == BobberState.LyingDown && headHeight > waterLevel - 0.02f)
            state = BobberState.RisingUp;

        if (state == BobberState.RisingUp && angle < 12f)
            state = BobberState.Standing;

        // 2. 挂底判定
        float tailHeight = transform.position.y - floatLength;
        if (tailHeight < waterLevel - 0.03f)
            state = BobberState.Bottom;

        // 3. 顶漂
        if (deltaY > 0.015f)
            state = BobberState.TopLift;

        // 4. 黑漂
        if (deltaY < -0.02f)
            state = BobberState.DownPull;

        // 5. 小顿口
        if (Mathf.Abs(deltaY) > 0.003f && Mathf.Abs(deltaY) < 0.015f)
            state = BobberState.Nibble;
    }

    // ---------------------------------------------------------------------
    // 垂直物理
    // ---------------------------------------------------------------------
    void ApplyPhysics()
    {
        float submerged = Mathf.Clamp01((waterLevel - transform.position.y) * 8f);
        float upForce = buoyancyForce * submerged - mass * 9.8f;

        verticalSpeed += upForce * Time.deltaTime;
        verticalSpeed = Mathf.Clamp(verticalSpeed, -0.2f, 0.2f);

        transform.position += new Vector3(0, verticalSpeed, 0);
    }

    // ---------------------------------------------------------------------
    // 倾斜角控制
    // ---------------------------------------------------------------------
    void ApplyRotation()
    {
        Quaternion q = Quaternion.Euler(angle, 0, 0);
        transform.rotation = Quaternion.Slerp(transform.rotation, q, Time.deltaTime * 8f);
    }
}