/*
    Copyright (c) [2023] [squallzhao]
    fountain is licensed under APACHE LICENSE, VERSION 2.0.
    You can use this software according to the terms and conditions of the APACHE LICENSE, VERSION 2.0.
    You may obtain a copy of APACHE LICENSE, VERSION 2.0 at: https://www.apache.org/licenses/LICENSE-2.0
*/
package microservice.resttemplate
import std.sync.*
import std.collection.*

public class RoundRobbin <: ILoadBalance{
    var restTemplate: RestTemplate
    var index = HashMap<String, AtomicInt64>()

    public init(restTemplate: RestTemplate){
        this.restTemplate = restTemplate
        for(service in restTemplate.getRefer().getRefers()){
            index.put(service,AtomicInt64(0))
        }
    }

    public func getServiceAddress(service: String):String{
        var arr : Option<ArrayList<String> > = restTemplate.getServiceAddressList(service)
        var num = index.get(service).getOrThrow()
        var pos = num.fetchAdd(1)
        return arr.getOrThrow()[pos % arr.getOrThrow().size]
    }
}