using UnityEngine;
using UnityEngine.Serialization;

// 入力に応じたPlayerの行動と状態遷移を管理する
[RequireComponent(typeof(DamageReceiver))]
[RequireComponent(typeof(HitReaction))]
public class PlayerController : MonoBehaviour
{
    [Tooltip("Playerの現在の状態")]
    [SerializeField] private PlayerState state = PlayerState.Idle;

    [Tooltip("Playerの移動処理")]
    [SerializeField] private PlayerMove playerMove;

    [Tooltip("カメラの回転処理")]
    [SerializeField] private CameraMove cameraMove;

    [FormerlySerializedAs("playerAttack")]
    [Tooltip("Playerの攻撃処理")]
    [SerializeField] private CharacterAttack characterAttack;

    private InputSystem_Actions _inputActions;
    private DamageReceiver _damageReceiver;
    private HitReaction _hitReaction;
    private bool _controlEnabled = true;

    public PlayerState State => state;

    // 入力と状態判定に必要なオブジェクトを準備する
    private void Awake()
    {
        _inputActions = new InputSystem_Actions();
        _damageReceiver = GetComponent<DamageReceiver>();
        _hitReaction = GetComponent<HitReaction>();
    }

    // Player用Input Actionを有効にする
    private void OnEnable()
    {
        _inputActions.Player.Enable();
        _damageReceiver.Died += OnDied;
    }

    // Player用Input Actionを無効にする
    private void OnDisable()
    {
        _damageReceiver.Died -= OnDied;
        _inputActions.Player.Disable();
    }

    // ゲーム状態に応じて入力と進行中の攻撃だけを停止・再開する
    public void SetControlEnabled(bool controlEnabled)
    {
        _controlEnabled = controlEnabled;

        if (controlEnabled)
            return;

        characterAttack.CancelAttack();

        if (state != PlayerState.Dead)
            SetState(PlayerState.Idle);
    }

    // 入力と優先度に従って状態を更新し、現在可能な行動を実行する
    private void Update()
    {
        if (state == PlayerState.Dead ||
            !_controlEnabled)
            return;

        var moveInput =
            _inputActions.Player.Move.ReadValue<Vector2>();
        var lookInput =
            _inputActions.Player.Look.ReadValue<Vector2>();

        cameraMove.Look(lookInput);

        if (_hitReaction.IsReacting)
        {
            SetState(PlayerState.Damage);
            return;
        }

        if (characterAttack.IsAttacking)
        {
            SetState(PlayerState.Attack);
            return;
        }

        if (_inputActions.Player.Attack.WasPressedThisFrame())
        {
            characterAttack.Attack();

            if (characterAttack.IsAttacking)
            {
                SetState(PlayerState.Attack);
                return;
            }
        }

        var forward = cameraMove.PlanarForward;
        var right = cameraMove.PlanarRight;
        var direction =
            forward * moveInput.y + right * moveInput.x;
        direction =
            Vector3.ClampMagnitude(direction, 1f);

        playerMove.Move(direction);

        SetState(
            direction == Vector3.zero
                ? PlayerState.Idle
                : PlayerState.Move);
    }

    // 死亡通知を受けた時点で、入力処理とは独立して死亡状態へ遷移する
    private void OnDied()
    {
        characterAttack.CancelAttack();
        SetState(PlayerState.Dead);
    }

    // 現在の状態を指定された状態へ変更する
    private void SetState(PlayerState nextState)
    {
        if (state == nextState)
            return;

        state = nextState;
    }
}