import {
    _decorator, CCInteger, Collider2D, Color, Component, Contact2DType,
    ERigidBody2DType, IPhysics2DContact, Node, PolygonCollider2D, RigidBody2D, Sprite, Vec2,
} from 'cc';
import { LuosiDing } from './LuosiDing';
const { ccclass, property } = _decorator;

/** 螺丝全部拔完后木板掉落时的整体色调 */
const BOARD_FALL_GRAY = '#646464';
/** 进入自由掉落后：本地 Y 低于此值（相对 layer）即可销毁 */
const BOARD_FALL_DESTROY_LOCAL_Y = -60;
/** 进入自由掉落后最长存活（秒） */
const BOARD_FALL_MAX_LIFE_SEC = 2.5;
/** 碰到 floor 后延迟销毁（秒） */
const BOARD_FALL_FLOOR_DESTROY_DELAY = 0.15;

/**木板子元素*/
@ccclass('Aelement')
export class Aelement extends Component {

    @property(CCInteger)
    aelementHoleNum: number = 2;

    /** 生成时孔洞螺丝总数 */
    private _initialScrewCount = 0;
    /** 木板上尚未脱落的螺丝数量（仅按 onScrewLeft 递减，不含铰链锚点） */
    private _remainingScrews = 0;
    /** 螺丝全部脱落后，开始检测木板掉落 */
    private _fallCheckEnabled = false;
    /** 已启用铰链约束物理（仅剩一颗螺丝） */
    private _constrainedPhysicsActive = false;
    /** 进入自由掉落累计时间 */
    private _fallLifeAcc = 0;
    private _fallContactBound = false;
    private _physicsActivating = false;

    /** 木板是否已进入掉落态（置灰），不再参与遮挡其它螺丝 */
    get isFalling(): boolean {
        return this._fallCheckEnabled;
    }

    /** 仅剩一颗螺丝、绕铰链摆动中 */
    get isSwinging(): boolean {
        return this._constrainedPhysicsActive && !this._fallCheckEnabled;
    }

    /** 获取木板上所有孔洞节点（孔洞1、孔洞2…） */
    getHoleNodes(): Node[] {
        return this.node.children
            .filter((c) => c.name.startsWith('孔洞'))
            .sort((a, b) => a.name.localeCompare(b.name, 'zh'));
    }

    /** 生成螺丝后登记数量 */
    initScrewCount(count: number) {
        this._initialScrewCount = count;
        this._remainingScrews = count;
        this._fallCheckEnabled = false;
        this._constrainedPhysicsActive = false;
        this._fallLifeAcc = 0;
        this._physicsActivating = false;
    }

    /** 螺丝从木板上脱落（弹出或消除）时由 LuosiDing 调用 */
    onScrewLeft() {
        if (this._remainingScrews > 0) {
            this._remainingScrews--;
        }
        this._applyPhysicsForScrewCount();
    }

    /** 复活 / 广告消钉后：按孔洞内实际螺丝数恢复 */
    reconcilePhysicsState() {
        if (!this.node?.isValid) return;
        this._remainingScrews = LuosiDing.countAttachedScrewsInHoles(this.node);
        this._applyPhysicsForScrewCount();
    }

    /**
     * 物理策略（贴近 prefab，不注入角速度）：
     * - 2+ 颗螺丝：静态节点树固定，不进物理（避免过约束抖动）
     * - 1 颗螺丝：Dynamic + 单铰链，绕螺丝重心自然摆动
     * - 0 颗螺丝：脱离铰链，重力自由滑落
     */
    private _applyPhysicsForScrewCount() {
        if (this._remainingScrews > 1) {
            this._fallCheckEnabled = false;
            this._fallLifeAcc = 0;
            this._constrainedPhysicsActive = false;
            this._unbindFallContact();
            LuosiDing.detachAllBoardHinges(this.node);
            this.prepareColliderForGameplay();
            return;
        }
        if (this._remainingScrews === 1) {
            this._enterConstrainedPhysics();
            return;
        }
        if (this._initialScrewCount > 0) {
            this._enterFreeFall();
        }
    }

    private _enterConstrainedPhysics() {
        this._fallCheckEnabled = false;
        this._fallLifeAcc = 0;
        this._unbindFallContact();
        this.beginConstrainedPhysics();
    }

    private _enterFreeFall() {
        if (!this.node?.isValid) return;
        if (!this._fallCheckEnabled) {
            this._applyFallGrayColor();
        }
        this._fallCheckEnabled = true;
        this._constrainedPhysicsActive = false;
        this._fallLifeAcc = 0;
        LuosiDing.detachAllBoardHinges(this.node);
        this.beginFallingPhysics();
    }

    /** 螺丝拔完开始掉落时，将木板及子节点 Sprite 整体置灰 */
    private _applyFallGrayColor() {
        const gray = new Color().fromHEX(BOARD_FALL_GRAY);
        const visit = (n: Node) => {
            const sp = n.getComponent(Sprite);
            if (sp) sp.color = gray;
            for (const child of n.children) visit(child);
        };
        visit(this.node);
    }

    /**
     * 玩法阶段：刚体与碰撞体均不进物理世界；Polygon 顶点仍可供 LuosiDing 几何遮挡检测。
     */
    prepareColliderForGameplay() {
        this.unschedule(this._activateConstrainedRigidbody);
        this.unschedule(this._activateFallRigidbody);
        this._physicsActivating = false;
        this._unbindFallContact();
        LuosiDing.detachAllBoardHinges(this.node);
        this._constrainedPhysicsActive = false;
        const rb = this.node.getComponent(RigidBody2D);
        if (rb) {
            rb.enabled = false;
            rb.linearVelocity = Vec2.ZERO;
            rb.angularVelocity = 0;
        }
        const poly = this.node.getComponent(PolygonCollider2D);
        if (poly) {
            poly.enabled = false;
        }
    }

    /** 仅剩一颗螺丝：Dynamic + 单铰链，受重力自然摆 */
    beginConstrainedPhysics() {
        if (this._physicsActivating) return;
        this.unschedule(this._activateConstrainedRigidbody);
        this.scheduleOnce(this._activateConstrainedRigidbody, 0.06);
    }

    private _activateConstrainedRigidbody = () => {
        if (!this.node?.isValid || this._fallCheckEnabled || this._remainingScrews !== 1) return;
        this._physicsActivating = true;

        const rb = this.node.getComponent(RigidBody2D);
        if (!rb) {
            this._physicsActivating = false;
            return;
        }

        if (rb.enabled) {
            rb.enabled = false;
        }
        // 传感器：不与堆叠木板/斜坡产生分离冲量，只靠铰链+重力按重心摆
        this._enableBoardCollider(true);

        rb.enabled = true;
        rb.type = ERigidBody2DType.Dynamic;
        rb.gravityScale = 5;
        rb.linearDamping = 0.2;
        rb.angularDamping = 5;
        rb.fixedRotation = false;
        rb.allowSleep = true;
        rb.bullet = false;
        rb.enabledContactListener = false;
        rb.linearVelocity = Vec2.ZERO;
        rb.angularVelocity = 0;

        LuosiDing.refreshBoardHinges(this.node);
        rb.wakeUp();
        this._constrainedPhysicsActive = true;
        this._physicsActivating = false;
    };

    /** 螺丝全部拔完后脱离铰链，沿斜坡自然滑落 */
    beginFallingPhysics() {
        LuosiDing.detachAllBoardHinges(this.node);
        this.unschedule(this._activateFallRigidbody);
        this.scheduleOnce(this._activateFallRigidbody, 0.06);
    }

    private _activateFallRigidbody = () => {
        if (!this._fallCheckEnabled || !this.node?.isValid) return;
        this._physicsActivating = true;

        const rb = this.node.getComponent(RigidBody2D);
        if (!rb) {
            this._physicsActivating = false;
            return;
        }

        if (rb.enabled) {
            rb.enabled = false;
        }
        this._enableBoardCollider(false);
        this._bindFallContact();

        rb.enabled = true;
        rb.type = ERigidBody2DType.Dynamic;
        rb.gravityScale = 5;
        rb.linearDamping = 0.2;
        rb.angularDamping = 5;
        rb.fixedRotation = false;
        rb.allowSleep = true;
        rb.bullet = false;
        rb.enabledContactListener = true;
        rb.linearVelocity = Vec2.ZERO;
        rb.angularVelocity = 0;
        rb.wakeUp();
        this._physicsActivating = false;
    };

    private _bindFallContact() {
        if (this._fallContactBound) return;
        const col = this.node.getComponent(Collider2D);
        if (!col) return;
        col.on(Contact2DType.BEGIN_CONTACT, this._onFallFloorContact, this);
        this._fallContactBound = true;
    }

    private _unbindFallContact() {
        if (!this._fallContactBound) return;
        const col = this.node.getComponent(Collider2D);
        col?.off(Contact2DType.BEGIN_CONTACT, this._onFallFloorContact, this);
        this._fallContactBound = false;
    }

    private _scheduleFloorDestroy = () => {
        this._destroyFallenBoard();
    };

    private _onFallFloorContact(_self: Collider2D, other: Collider2D, _contact: IPhysics2DContact | null) {
        if (!this._fallCheckEnabled || !other?.node?.isValid) return;
        const n = other.node.name;
        const p = other.node.parent?.name ?? '';
        if (n.indexOf('floor') >= 0 || p === 'ui_floorNode') {
            this.scheduleOnce(this._scheduleFloorDestroy, BOARD_FALL_FLOOR_DESTROY_DELAY);
        }
    }

    private _enableBoardCollider(sensor: boolean) {
        const poly = this.node.getComponent(PolygonCollider2D);
        if (!poly) return;
        poly.enabled = true;
        poly.sensor = sensor;
        poly.friction = 0.4;
        poly.restitution = 0;
        const apply = (poly as { apply?: () => void }).apply;
        if (typeof apply === 'function') apply.call(poly);
    }

    private _destroyFallenBoard() {
        if (!this.node?.isValid) return;
        this.unschedule(this._scheduleFloorDestroy);
        this._unbindFallContact();
        const rb = this.node.getComponent(RigidBody2D);
        if (rb) rb.enabled = false;
        this.node.destroy();
    }

    onDestroy() {
        this._unbindFallContact();
    }

    update(dt: number) {
        if (!this.node?.isValid) return;

        if (!this._fallCheckEnabled) {
            if (this._remainingScrews <= 0 && this._initialScrewCount > 0
                && LuosiDing.countAttachedScrewsInHoles(this.node) === 0) {
                this._enterFreeFall();
            }
            return;
        }

        this._fallLifeAcc += dt;

        if (this._fallLifeAcc >= BOARD_FALL_MAX_LIFE_SEC) {
            this._destroyFallenBoard();
            return;
        }

        if (this.node.position.y < BOARD_FALL_DESTROY_LOCAL_Y) {
            this._destroyFallenBoard();
            return;
        }

        const rb = this.node.getComponent(RigidBody2D);
        if (!rb?.enabled && !this._physicsActivating) {
            this._activateFallRigidbody();
        }
    }
}