using System;
using UnityEngine;

using Spine.Unity;

[Serializable]
public struct IVMateProperty
{
    public uint id;
    public float defaultSkillCoolTime;
    public float defaultMoveSpeed;
}

public class IVMate : MonoBehaviour
{
    [SerializeField] IVMateProperty property;
    [SerializeField] SkeletonAnimation skeletonAnimation;
    [SerializeField] StateHandler stateHandler;

    float elapsedCoolTime;

    public IVMateProperty Property => property;
    public SkeletonAnimation SkeletonAnimation => skeletonAnimation;

    public float ElapsedCoolTimeRate { get; private set; }
    public bool IsAvailableSkill => elapsedCoolTime >= property.defaultSkillCoolTime;
    public bool IsSafeToCallUseSkill => stateHandler.CurrentState is IVMateIdleState;
    public Vector2 LookDirection { get; private set; }

    public void UpdateSkillCoolTime()
    {
        if (elapsedCoolTime >= property.defaultSkillCoolTime) return;
        elapsedCoolTime += Time.fixedUnscaledDeltaTime;
        ElapsedCoolTimeRate = Mathf.Clamp01(elapsedCoolTime / property.defaultSkillCoolTime);
    }

    public void Spawn(IVCharacter player, Vector2 lookDir, Transform spawnPosition = null)
    {
        elapsedCoolTime = 0f;

        if(spawnPosition != null)
        {
            transform.position = spawnPosition.position;
        }
        else
        {
            var rnd = UnityEngine.Random.insideUnitCircle * GameProperty.Instance.DistFromPlayerWhenFirstMateSpawn;
            transform.position = player.transform.position + new Vector3(rnd.x, rnd.y, 0f);
        }

        ChangeLookDirection(lookDir);

        gameObject.SetActive(true);

        stateHandler?.ChangeState(new IVMateAppearState(this, player));
    }

    public void Dispose()
    {
        stateHandler?.ChangeState(new IVMateDisappearState(this, () => gameObject.SetActive(false)));
    }

    public void UseSkill()
    {
        if (!IsSafeToCallUseSkill || !IsAvailableSkill) return;
        elapsedCoolTime = 0f;

        // TODO: change state to use skill
    }

    public void ChangeLookDirection(Transform lookTarget)
    {
        ChangeLookDirection((Vector2)lookTarget.position - (Vector2)transform.position);
    }

    public void ChangeLookDirection(Vector2 lookDirection)
    {
        if (lookDirection.x >= 0)
        {
            LookDirection = Vector2.right;
            transform.rotation = Quaternion.Euler(Vector3.zero);
        }
        else
        {
            LookDirection = Vector2.left;
            transform.rotation = Quaternion.Euler(Global.V3_RotRev);
        }
    }
}