module.exports = function (RED) {
  function heatExchanger(config) {
    //create node
    RED.nodes.createNode(this, config);
    //call this => node so whenver you want to call a node function type node and the function behind it
    var node = this;
    
    try{

      //fetch heatExchanger object from source.js
      const heatExchanger = require("./dependencies/heatExchanger/heatExchanger");
      const OutputUtils = require("../generalfunctions/helper/outputUtils");

      //load user defined config in the node-red UI
      const heConfig={
        general: {
          name: config.name,
          id: node.id,
          unit: config.unit,
          logging:{
            logLevel: config.logLevel,
            enabled: config.enableLog,
          },
        },
        asset: {
          tagCode: config.assetTagCode, 
          supplier: config.supplier,
          subType: config.subType,
          model: config.model,
        }
      }
    
      //make new heatExchanger on creation to work with.
      const he = new heatExchanger(heConfig);

      // put m on node memory as source
      node.source = he;

      //load output utils
      const output = new OutputUtils();

      function updateNodeStatus(val) {
        //display status
        node.status({ fill: "green", shape: "dot", text: val + " " + heConfig.general.unit });
      }
      
      function tick() {
        try {
          //const status = updateNodeStatus();
          //node.status(status);

          //get output
          const classOutput = he.getOutput();
          const dbOutput = output.formatMsg(classOutput, he.config, "influxdb");
          const pOutput = output.formatMsg(classOutput, he.config, "process");

          //only send output on values that changed
          let msgs = [];
          msgs[0] = pOutput;
          msgs[1] = dbOutput;

          node.send(msgs);

        } catch (error) {
          node.error("Error in tick function: " + error);
          node.status({ fill: "red", shape: "ring", text: "Tick Error" });
        }
      }

      // register child on first output this timeout is needed because of node - red stuff
      setTimeout(
        () => {
          
          /*---execute code on first start----*/
          let msgs = [];

          msgs[2] = { topic : "registerChild" , payload: node.id, positionVsParent: "upstream" };
          msgs[3] = { topic : "registerChild" , payload: node.id, positionVsParent: "downstream" };
          
          //send msg
          this.send(msgs);
        }, 
        100
      );

      //declare refresh interval internal node
      setTimeout(
        () => {
          /*---execute code on first start----*/
          this.intervalId = setInterval(function(){ tick() },1000)
        }, 
        1000
      );
    
      //-------------------------------------------------------------------->>what to do on input
      node.on("input", function (msg,send,done) {

        // augment this later with child connections
        if(msg.topic == "TempHotInput")
        {
          if(msg.payload.mAbs){
            he.setHotInput(msg.payload.mAbs);
            console.log("HotInput: " + msg.payload);
          }
        }

        if(msg.topic == "TempColdInput")
        {
          if(msg.payload.mAbs){
            he.setColdInput(msg.payload.mAbs);
            console.log("ColdInput: " + msg.payload);
          }

        }

        if(msg.topic == "FlowRateHot"){
          if(msg.payload.downstream_predicted_flow){
            he.setHotFlowRate(msg.payload.downstream_predicted_flow);
            console.log("FlowRateHot: " + msg.payload.downstream_predicted_flow);
          }

        }

        if(msg.topic == "FlowRateCold"){
          if(msg.payload.downstream_predicted_flow){
            he.setColdFlowRate(msg.payload.downstream_predicted_flow);
            console.log("FlowRateCold: " + msg.payload.downstream_predicted_flow);
          }
        }

        done();

      });

      // tidy up any async code here - shutdown connections and so on.
      node.on('close', function(done) {
        if (node.intervalId) clearTimeout(node.intervalId);
        if (node.tickInterval) clearInterval(node.tickInterval);
        if (done) done();
      });
      
    }catch(e){
      console.log(e);
    }
  }
  RED.nodes.registerType("heatExchanger", heatExchanger);
};