using UnityEngine;

/// <summary>
/// ควบคุมตัวละคร: เดินตามทิศทางกล้อง (WASD) และหันหน้าไปทางที่เดิน
/// ใส่สคริปต์นี้ที่ตัว Player (ต้องมี CharacterController)
/// </summary>
[RequireComponent(typeof(CharacterController))]
public class PlayerController : MonoBehaviour
{
    [Header("Camera")]
    [Tooltip("เว้นว่างไว้ = ใช้ Main Camera")]
    [SerializeField] private Transform cameraTransform;

    [Header("Movement")]
    [SerializeField] private float walkSpeed = 4f;
    [SerializeField] private float sprintSpeed = 7f;
    [Tooltip("ยิ่งมากยิ่งหันตัวเร็ว")]
    [SerializeField] private float turnSpeed = 12f;

    [Header("Jump / Gravity")]
    [SerializeField] private float jumpHeight = 1.2f;
    [SerializeField] private float gravity = -20f;

    [Header("Animator (ไม่บังคับ)")]
    [SerializeField] private Animator animator;
    [SerializeField] private string speedParameter = "Speed";

    private CharacterController controller;
    private float verticalVelocity;
    private int speedHash;
    private bool hasSpeedParam;

    private void Awake()
    {
        controller = GetComponent<CharacterController>();

        if (cameraTransform == null && Camera.main != null)
            cameraTransform = Camera.main.transform;

        if (animator != null)
        {
            speedHash = Animator.StringToHash(speedParameter);
            foreach (var p in animator.parameters)
                if (p.nameHash == speedHash) { hasSpeedParam = true; break; }
        }
    }

    private void Update()
    {
        if (cameraTransform == null) return;

        // ----- ทิศทางเดินอิงตามกล้อง -----
        Vector2 input = GameInput.Move;

        Vector3 camForward = cameraTransform.forward;
        camForward.y = 0f;
        camForward.Normalize();
        Vector3 camRight = cameraTransform.right;
        camRight.y = 0f;
        camRight.Normalize();

        Vector3 moveDir = camForward * input.y + camRight * input.x;
        bool moving = moveDir.sqrMagnitude > 0.0001f;

        // ----- หันหน้าไปทางที่เดิน -----
        if (moving)
        {
            Quaternion targetRot = Quaternion.LookRotation(moveDir, Vector3.up);
            transform.rotation = Quaternion.Slerp(
                transform.rotation, targetRot, 1f - Mathf.Exp(-turnSpeed * Time.deltaTime));
        }

        // ----- ความเร็ว -----
        float speed = GameInput.SprintHeld ? sprintSpeed : walkSpeed;

        // ----- แรงโน้มถ่วง / กระโดด -----
        if (controller.isGrounded && verticalVelocity < 0f)
            verticalVelocity = -2f;

        if (controller.isGrounded && GameInput.JumpPressed)
            verticalVelocity = Mathf.Sqrt(jumpHeight * -2f * gravity);

        verticalVelocity += gravity * Time.deltaTime;

        Vector3 velocity = moveDir * speed;
        velocity.y = verticalVelocity;
        controller.Move(velocity * Time.deltaTime);

        // ----- Animator -----
        if (hasSpeedParam)
            animator.SetFloat(speedHash, moving ? speed : 0f, 0.1f, Time.deltaTime);
    }
}