import { _decorator, instantiate, Node, NodePool, Prefab } from 'cc';
import { ResManager } from './ResManager';
const { ccclass, property } = _decorator;

@ccclass('NodePoolManager')
export class NodePoolManager {
    private static _instance: NodePoolManager = null;
    private _nodePoolMap: Map<string, NodePool> = null;

    static get instance() {
        if (this._instance) {
            return this._instance;
        }
        this._instance = new NodePoolManager();
        return this._instance;
    }

    constructor() {
        this._nodePoolMap = new Map<string, NodePool>();
    }

    // 内部调用，通过name获取节点池
    getNodePoolByName(name: string): NodePool {
        if (!this._nodePoolMap.has(name)) {
            let nodePool = new NodePool(name);
            this._nodePoolMap.set(name, nodePool)
        }
        let nodePool = this._nodePoolMap.get(name);
        return nodePool
    }

    getNodeFromPoolStatic(name: string, prefab?: Prefab): Node | null {
        let nodePool = this.getNodePoolByName(name);
        let poolSize = nodePool.size();
        if (poolSize <= 0) {
            let node = instantiate(prefab);
            nodePool.put(node);
        }
        return nodePool.get();
    }

    putNodeToPool(name: string, node: Node) {
        let nodePool = this.getNodePoolByName(name);
        nodePool.put(node);
    }

    clearNodePoolByName(name: string) {
        let nodePool = this.getNodePoolByName(name);
        nodePool.clear();
        if (this._nodePoolMap.has(name)) {
            this._nodePoolMap.delete(name);
        }
    }

    clearAll() {
        this._nodePoolMap.forEach(value => {
            value.clear();
        })
        this._nodePoolMap.clear();
    }

    static destoryInstance() {
        this._instance = null;
    }
}