import { NFNode } from "./node";
import { NFNodeCfg, NFNodeType } from "../types";
import { NFSequenceNode } from "./sequencenode";
import { NFProcess } from "../process";
import { NFError } from "../error";

/**
 * 并行网关（AND）
 * - 分叉：无条件激活全部出口
 * - 汇聚：等待全部入边到达后再继续
 */
export class NFParallelNode extends NFNode{
    /**
     * 出口顺序流
     */
    outSequences:NFSequenceNode[];

    /**
     * 入口顺序流
     */
    inSequences:NFSequenceNode[];

    /**
     * 汇聚剩余待到达数量
     */
    inCount:number;
    
    /**
     * @param cfg - 节点配置
     * @param process - 所属流程
     */
    constructor(cfg:NFNodeCfg,process:NFProcess){
        super(cfg,process);
        this.type = NFNodeType.PARALLEL;
    }
    
    /**
     * 汇聚全部入边后无条件激活全部出口。
     */
    async run() {
        await super.run();

        // 多入边：汇聚，必须等全部到达
        if(this.inSequences.length > 1){
            if(--this.inCount > 0){
                await this.process.saveGatewayNodeState(this.id,{inCount:this.inCount});
                return;
            }
            await this.process.clearGatewayNodeState(this.id);
            this.inCount = this.inSequences.length;
        }

        // 分叉/继续：无条件执行全部出口
        for(let seq of this.outSequences){
            await seq.run(true);
        }
    }

    /**
     * 绑定入边 / 出边并初始化汇聚计数。
     *
     * @throws `1101` 当缺少入边或出边
     */
    init(){
        this.outSequences = this.process.nodeManager.getSequenceNodes(this.id);
        this.inSequences = this.process.nodeManager.getSequenceNodes(this.id,true);
        if(!this.outSequences || this.outSequences.length === 0 || !this.inSequences || this.inSequences.length === 0){
            throw new NFError("1101",[this.name || this.id]);
        }
        this.inCount = this.inSequences.length;
    }

    /**
     * 恢复运行时计数（`getInstance`）。
     *
     * @param state - 剩余待到达数量
     */
    restoreState(state:{inCount?:number}){
        if(state && typeof state.inCount === 'number'){
            this.inCount = state.inCount;
        }
    }
}