/**
 * 控制器辅助函数。
 *
 * author: Sand
 * since: 2016/11/22
 */
"use strict";

const MODEL_EVENTS = require("../include/commons").MODEL_EVENTS;

/**
 * 根据模型事件注册响应返回的代码。
 */
class ControllerUtil {
    constructor(){}

    static regModelEventHandler(model, response) {
        model.on(MODEL_EVENTS.OK, function (data) {
            response.status(200).json(data);
        });

        model.on(MODEL_EVENTS.DataNotFound, function (data) {
            response.status(404).json(data);
        });

        model.on(MODEL_EVENTS.Error, function (data) {
            response.status(500).json(data);
        });
    }

    static checkRequestQueryParams(req, params){
        let message = "Missing field(s): ";
        let missingField = false;

        params.forEach(function (param) {
            if(!req.query.hasOwnProperty(param)){
                message += param + ",";
                missingField = true;
            }
        });

        if(missingField) throw {message: message};
    }
}

module.exports = ControllerUtil;