node-red-contrib-dellmonitor/CS5517H.js

RS232 over network control of a Dell CS5517H LCD Monitor

var commands = require("./commands.js");
module.exports = function(RED)
{
    //Main Function
    function DellCS5517H(config)
    {
        RED.nodes.createNode(this, config);
        var network = RED.nodes.getNode(config.network);
        var node = this;

        network.link(node);
        node.on("close", function() {
            network.server.close();
        });

        node.on("input", function(msg) {
            if(msg.payload === undefined || msg.payload === null) {
                RED.log.error("No msg.payload");
                node.status({fill:"red",shape:"dot",text:"Syntax Error"});
                return;
            }
            if(msg.payload.direction === undefined || msg.payload.direction === null) {
                RED.log.error("msg.payload.direction Not Stated");
                node.status({fill:"red",shape:"dot",text:"Syntax Error"});
                return;
            }
            if(msg.payload.command === undefined || msg.payload.command === null) {
                RED.log.error("msg.payload.command Not Stated");
                node.status({fill:"red",shape:"dot",text:"Syntax Error"});
                return;
            }

            var command = undefined;
            var direction = msg.payload.direction.toString().toLowerCase();
            if(direction !== "set" && direction !== "get"){direction = undefined;}
            for(var key in commands.command) {
                if(key.toString().toLowerCase() == msg.payload.command.toString().toLowerCase()) {
                    command = msg.payload.command.toString().toLowerCase();
                }
            }

            if(direction === undefined || direction === null) {
                RED.log.error("msg.payload.direction Syntax Error");
                node.status({fill:"red",shape:"dot",text:"Syntax Error"});
                return;
            }
            else if(command === undefined || command === null) {
                RED.log.error("msg.payload.command Syntax Error");
                node.status({fill:"red",shape:"dot",text:"Syntax Error"});
                return;
            }

            var sendOut = function(powerState) {
                if(powerState == false) {
                    if(command.toString().toLowerCase() == "powerstate" && msg.payload.data == "on") {
                        var buffer = commands.generateBuffer("set", command, msg.payload.data);
                        network.server.send(buffer, function(state){
                            if(state == false) {
                                RED.log.error("Failed To Send Command, Check The RS232 Connection");
                                node.status({fill:"red",shape:"dot",text:"Failed To Send"});
                            }
                        }, function(message){
                            return true;
                        }); 
                    }
                    else {
                        RED.log.error("Cannot Send While Monitor Is Turned Off");
                        node.status({fill:"red",shape:"dot",text:"Failed To Send"});
                    }
                }
                else {
                    var buffer = commands.generateBuffer("set", command, msg.payload.data);
                    network.server.send(buffer, function(state){
                        if(state == false) {
                            RED.log.error("Failed To Send Command");
                            node.status({fill:"red",shape:"dot",text:"Failed To Send"});
                        }
                    }, function(message){
                        return true;
                    });
                }
            }

            //Check if the monitor is off, if so only allow a on command
            var buffer = commands.generateBuffer("get", "powerstate");
            network.server.send(buffer, function(state){}, function(message) {
                if(commands.isReceivedValid(message)){
                    if(commands.getCommand(message) == "powerState") {
                        if(commands.getData(message) == "off") {
                            sendOut(false);
                            return true;
                        }
                        else {
                            sendOut(true);
                            return true;
                        }
                    }
                }
            });
        });
    }
    RED.nodes.registerType("dell-CS5517H", DellCS5517H);
}