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

public class BulletCurve
{
    protected BattleObject caster;
    protected SkillConfig skillConfig;
    protected BattleEffectPlayer bulletEffect;
    protected RectTransform bulletTrans; // 子弹的RectTransform
    protected RectTransform target;
    protected Action<int, List<HB427_tagSCUseSkill.tagSCUseSkillHurt>> onHit;

    protected Vector2 bulletOffset = Vector2.zero;

    protected bool finished = false;
    protected float duration = 0f;
    protected float elapsed = 0f;

    protected int mBulletIndex;

    protected List<HB427_tagSCUseSkill.tagSCUseSkillHurt> hurts = new List<HB427_tagSCUseSkill.tagSCUseSkillHurt>();

    public BulletCurve(BattleObject caster, SkillConfig skillConfig, BattleEffectPlayer bulletEffect, RectTransform target,
        List<HB427_tagSCUseSkill.tagSCUseSkillHurt> hurtList, int bulletIndex, Action<int, List<HB427_tagSCUseSkill.tagSCUseSkillHurt>> onHit)
    {
        this.caster = caster;
        this.skillConfig = skillConfig;
        this.bulletEffect = bulletEffect;
        this.target = target;
        this.onHit = onHit;
        this.bulletTrans = bulletEffect.rectTrans;
        this.hurts = hurtList;
        this.mBulletIndex = bulletIndex;

        // 设置bulletTrans坐标为caster.heroRectTrans的世界坐标转换到bulletTrans父节点下的本地坐标
        if (bulletTrans != null && caster.heroRectTrans != null)
        {
            var parent = bulletTrans.parent as RectTransform;
            Vector2 localPoint;
            RectTransformUtility.ScreenPointToLocalPointInRectangle(
                parent,
                RectTransformUtility.WorldToScreenPoint(null, caster.heroRectTrans.position),
                null,
                out localPoint);
            bulletTrans.anchoredPosition = localPoint;
        }

        if (bulletEffect.effectConfig.effectPos != null && bulletEffect.effectConfig.effectPos.Length >= 2)
        {
            bulletOffset = new Vector2(bulletEffect.effectConfig.effectPos[0], bulletEffect.effectConfig.effectPos[1]);
        }
    }

    public virtual void Reset()
    {
        finished = false;
        elapsed = 0f;
    }

    // 世界坐标转为bulletTrans父节点下的本地坐标
    protected Vector2 WorldToLocalAnchoredPosition(Vector3 worldPos)
    {
        var parent = bulletTrans.parent as RectTransform;
        Vector2 localPoint;
        RectTransformUtility.ScreenPointToLocalPointInRectangle(parent, RectTransformUtility.WorldToScreenPoint(null, worldPos), null, out localPoint);
        return localPoint;
    }

    // Run就是Update，每帧调用
    public virtual void Run()
    {
        if (finished) return;
        Vector2 targetPos = WorldToLocalAnchoredPosition(target.position);
        bulletTrans.anchoredPosition = targetPos;
        ReachTarget();
    }

    protected virtual void ReachTarget()
    {
        finished = true;
        onHit?.Invoke(mBulletIndex, hurts);
        caster.battleField.battleEffectMgr.RemoveEffect(skillConfig.BulletEffectId, bulletEffect);
    }

    public virtual void ForceFinish()
    {
        finished = true;
    }

    public bool IsFinished => finished;
}