package autodig.client.service;

import autodig.client.config.DigConfig;
import net.minecraft.client.MinecraftClient;
import net.minecraft.entity.Entity;
import net.minecraft.entity.LivingEntity;
import net.minecraft.entity.mob.Monster;
import net.minecraft.util.math.Box;
import net.minecraft.util.math.Vec3d;

/**
 * 杀戮光环服务。
 *
 * <p>在开关开启时，自动攻击以玩家为中心、指定半径内最近的敌对生物
 * （{@link Monster}）。攻击前会转向目标方向；"安全模式"开启时，
 * 玩家生命过低则停止攻击、保命优先。</p>
 */
public final class KillAura {

    /** 攻击节流：每 N tick 才允许挥一刀，避免疯狂连点 */
    private int attackCooldownTicks;

    /**
     * 每帧调用。执行杀戮光环逻辑（开关关闭时直接返回）。
     *
     * @param config 挖矿配置
     */
    public void tick(DigConfig config) {
        MinecraftClient client = MinecraftClient.getInstance();
        if (client.player == null || client.world == null || client.interactionManager == null) {
            return;
        }
        if (!config.killAura) {
            return;
        }
        net.minecraft.entity.player.PlayerEntity player = client.player;
        if (player.isDead()) {
            return;
        }
        // 安全模式：血线过低不出击
        if (config.killAuraSafe) {
            double health = player.getHealth() / Math.max(player.getMaxHealth(), 1.0) * 100.0;
            if (health < config.healthFleeThreshold) {
                return;
            }
        }
        // 挥刀节流
        if (this.attackCooldownTicks > 0) {
            this.attackCooldownTicks--;
            return;
        }
        // 攻击冷却未转好则等待
        if (player.getAttackCooldownProgress(0.5f) < 1.0f) {
            return;
        }
        Entity target = this.findNearestHostile(client, player, config.killRange);
        if (target == null) {
            return;
        }
        // 转向目标
        this.faceEntity(player, target);
        client.interactionManager.attackEntity(player, target);
        this.attackCooldownTicks = 4; // 约 4 tick 一刀
    }

    /** 在玩家周围范围内找最近的敌对生物。 */
    private Entity findNearestHostile(MinecraftClient client, LivingEntity player, double range) {
        range = Math.max(2.0, range);
        Box box = player.getBoundingBox().expand(range);
        Entity best = null;
        double bestDist = Double.MAX_VALUE;
        for (Entity e : client.world.getEntitiesByClass(Entity.class, box, e -> e instanceof Monster && e.isAlive())) {
            double d = e.squaredDistanceTo(player);
            if (d < bestDist) {
                bestDist = d;
                best = e;
            }
        }
        return best;
    }

    /** 让玩家面朝向实体。 */
    private void faceEntity(LivingEntity player, Entity target) {
        Vec3d p = player.getEyePos();
        Vec3d t = target.getEyePos();
        double dx = t.x - p.x;
        double dy = t.y - p.y;
        double dz = t.z - p.z;
        double d = Math.sqrt(dx * dx + dz * dz);
        float yaw = (float) (Math.toDegrees(Math.atan2(dz, dx)) - 90.0);
        float pitch = (float) (-Math.toDegrees(Math.atan2(dy, Math.max(d, 0.0001))));
        player.setYaw(yaw);
        player.setPitch(pitch);
    }
}