const { ccclass, property } = cc._decorator;

@ccclass
export default class PrefabManager {
    private static _prefabMap: { [key: string]: cc.Prefab } = {};

    private static _prefabDic: { [key: string]: cc.Node } = {};

    /**
     * 加载指定路径下的预制体
     * @param path 预制体的路径
     * @param callback 加载完成后的回调函数
     */
    public static loadPrefab(path: string, callback: (prefab: cc.Prefab) => void) {
        if (path in this._prefabMap) {
            callback(this._prefabMap[path]);
        } else {
            cc.resources.load(path, cc.Prefab, (err, prefab: cc.Prefab) => {
                if (err) {
                    cc.error(err.message || err);
                    return;
                }
                this._prefabMap[path] = prefab;
                callback(prefab);
            });
        }
    }

    /**
     * 打开指定路径下的预制体
     * @param path 预制体的路径
     * @param parentNode 预制体的父节点
     * @param callback 预制体加载完成后的回调函数
     */
    public static open(path: string, parentNode?: cc.Node, callback?: (node: cc.Node) => void) {
        // 如果已经加载过了，就直接显示
        if (this._prefabDic[path] != undefined) {
            this._prefabDic[path].active = true;
        } else {
            this.loadPrefab(path, (prefab) => {
                let node = cc.instantiate(prefab);
                if (parentNode) {
                    node.parent = parentNode;
                    node.setPosition(cc.v2(0, 0));
                    this._prefabDic[path] = node;
                }
                if (callback) {
                    callback(node);
                }
            });
        }
    }

    /**
     * 关闭指定路径下的预制体
     * @param path 预制体的路径
     * @param node 预制体的节点
     */
    public static close(node: cc.Node | string) {
        if ( typeof node == 'string'){
            this._prefabDic[node].active = false;
        } else if (node.isValid){
            node.active = false;
        }
    }

    /** 遍历所有 this._prefabDic里面已隐藏的节点*/
    public static closeAll() {
        // for (let key in this._prefabDic) {
        //     if (this._prefabDic[key].active) {
        //         this._prefabDic[key].active = false;
        //     }
        // }
    }

}