module.exports = function(RED) {
    "use strict";
    var util = require("util");
    var events = require("events");
    const fs = require("fs-extra");
    const path = require("path");
    var debuglength = RED.settings.debugMaxLength || 1000;
    var useColors = RED.settings.debugUseColors || false;
    util.inspect.styles.boolean = "red";
    const { hasOwnProperty } = Object.prototype;

    function DebugNode(n) {
        var hasEditExpression = (n.targetType === "jsonata");
        var editExpression = hasEditExpression ? n.complete : null;
        RED.nodes.createNode(this,n);
        this.name = n.name;
        this.complete = hasEditExpression ? null : (n.complete||"payload").toString();
        if (this.complete === "false") { this.complete = "payload"; }
        this.console = ""+(n.console || false);
        this.tostatus = n.tostatus || false;
        this.statusType = n.statusType || "auto";
        this.statusVal = n.statusVal || this.complete;
        this.tosidebar = n.tosidebar;
        this.counter = 0;
        this.lastTime = new Date().getTime();
        this.timeout = null;
        if (this.tosidebar === undefined) { this.tosidebar = true; }
        this.active = (n.active === null || typeof n.active === "undefined") || n.active;
        if (this.tostatus) {
            this.status({fill:"grey", shape:"ring"});
            this.oldState = "{}";
        }

        var hasStatExpression = (n.statusType === "jsonata");
        var statExpression = hasStatExpression ? n.statusVal : null;

        var node = this;
        if ( node.statusType === "counter" ){
            node.status({fill:"blue", shape:"ring", text: node.counter});
        }
        else {
            node.status({fill:"", shape:"", text: ""});
        }
        var preparedEditExpression = null;
        var preparedStatExpression = null;
        if (editExpression) {
            try {
                preparedEditExpression = RED.util.prepareJSONataExpression(editExpression, this);
            }
            catch (e) {
                node.error(RED._("debug.invalid-exp", {error: editExpression}));
                return;
            }
        }
        if (statExpression) {
            try {
                preparedStatExpression = RED.util.prepareJSONataExpression(statExpression, this);
            }
            catch (e) {
                node.error(RED._("debug.invalid-exp", {error: editExpression}));
                return;
            }
        }

        function prepareValue(msg, done) {
            // Either apply the jsonata expression or...
            if (preparedEditExpression) {
                RED.util.evaluateJSONataExpression(preparedEditExpression, msg, (err, value) => {
                    if (err) { done(RED._("debug.invalid-exp", {error: editExpression})); }
                    else { done(null,{id:node.id, z:node.z, _alias: node._alias, path:node._flow.path, name:node.name, topic:msg.topic, msg:value}); }
                });
            } else {
                // Extract the required message property
                var property = "payload";
                var output = msg[property];
                if (node.complete !== "false" && typeof node.complete !== "undefined") {
                    property = node.complete;
                    try { output = RED.util.getMessageProperty(msg,node.complete); }
                    catch(err) { output = undefined; }
                }
                done(null,{id:node.id, z:node.z, _alias: node._alias,  path:node._flow.path, name:node.name, topic:msg.topic, property:property, msg:output});
            }
        }

        function prepareStatus(msg, done) {
            if (node.statusType === "auto") {
                if (node.complete === "true") {
                    done(null,{msg:msg.payload});
                }
                else {
                    prepareValue(msg,function(err,debugMsg) {
                        if (err) { node.error(err); return; }
                        done(null,{msg:debugMsg.msg});
                    });
                }
            }
            else {
                // Either apply the jsonata expression or...
                if (preparedStatExpression) {
                    RED.util.evaluateJSONataExpression(preparedStatExpression, msg, (err, value) => {
                        if (err) { done(RED._("debug.invalid-exp", {error:editExpression})); }
                        else { done(null,{msg:value}); }
                    });
                }
                else {
                    // Extract the required message property
                    var output;
                    try { output = RED.util.getMessageProperty(msg,node.statusVal); }
                    catch(err) { output = undefined; }
                    done(null,{msg:output});
                }
            }
        }
        this.on("close", function() {
            if (this.oldState) {
                this.status({});
            }
            if (this.timeout) {
                clearTimeout(this.timeout)
            }
        })
        this.on("input", function(msg, send, done) {
            if (hasOwnProperty.call(msg, "status") && hasOwnProperty.call(msg.status, "source") && hasOwnProperty.call(msg.status.source, "id") && (msg.status.source.id === node.id)) {
                done();
                return;
            }
            if (node.tostatus === true) {
                if ( node.statusType === "counter" ){
                    const differenceOfTime  = (new Date().getTime() - node.lastTime);
                    node.lastTime = new Date().getTime();
                    node.counter++;
                    if ( differenceOfTime > 100 ){
                        node.status({fill:"blue", shape:"ring", text: node.counter});
                    }
                    else {
                        if (node.timeout) {
                            clearTimeout(node.timeout)
                        }
                        node.timeout = setTimeout(() => {
                            node.status({fill:"blue", shape:"ring", text: node.counter})
                        }, 200)
                    }
                } else {
                    prepareStatus(msg, function(err,debugMsg) {
                        if (err) { node.error(err); return; }
                        var output = debugMsg.msg;
                        var st = (typeof output === 'string') ? output : util.inspect(output);
                        var fill = "grey";
                        var shape = "dot";
                        if (typeof output === 'object' && hasOwnProperty.call(output, "fill") && hasOwnProperty.call(output, "shape") && hasOwnProperty.call(output, "text")) {
                            fill = output.fill;
                            shape = output.shape;
                            st = output.text;
                        }
                        if (node.statusType === "auto") {
                            if (hasOwnProperty.call(msg, "error")) {
                                fill = "red";
                                st = msg.error.message;
                            }
                            if (hasOwnProperty.call(msg, "status")) {
                                fill = msg.status.fill || "grey";
                                shape = msg.status.shape || "ring";
                                st = msg.status.text || "";
                            }
                        }

                        if (st.length > 32) { st = st.substr(0,32) + "..."; }

                        var newStatus = {fill:fill, shape:shape, text:st};
                        if (JSON.stringify(newStatus) !== node.oldState) { // only send if we have to
                            node.status(newStatus);
                            node.oldState = JSON.stringify(newStatus);
                        }
                    });
                }
            }

            if (this.complete === "true") {
                // debug complete msg object
                if (this.console === "true") {
                    node.log("\n"+util.inspect(msg, {colors:useColors, depth:10}));
                }
                if (this.active && this.tosidebar) {
                    sendDebug({id:node.id, z:node.z, _alias: node._alias,  path:node._flow.path, name:node.name, topic:msg.topic, msg:msg});
                }
                done();
            }
            else {
                prepareValue(msg,function(err,debugMsg) {
                    if (err) {
                        node.error(err);
                        return;
                    }
                    var output = debugMsg.msg;
                    if (node.console === "true") {
                        if (typeof output === "string") {
                            node.log((output.indexOf("\n") !== -1 ? "\n" : "") + output);
                        } else if (typeof output === "object") {
                            node.log("\n"+util.inspect(output, {colors:useColors, depth:10}));
                        } else {
                            node.log(util.inspect(output, {colors:useColors}));
                        }
                    }
                    if (node.active) {
                        if (node.tosidebar == true) {
                            sendDebug(debugMsg);
                        }
                    }
                    done();
                });
            }
        })
    }

    RED.nodes.registerType("debug",DebugNode, {
        settings: {
            debugUseColors: {
                value: false,
            },
            debugMaxLength: {
                value: 1000,
            }
        }
    });

    function sendDebug(msg) {
        // don't put blank errors in sidebar (but do add to logs)
        //if ((msg.msg === "") && (hasOwnProperty.call(msg, "level")) && (msg.level === 20)) { return; }
        msg = RED.util.encodeObject(msg,{maxLength:debuglength});
        RED.comms.publish("debug",msg);
    }

    DebugNode.logHandler = new events.EventEmitter();
    DebugNode.logHandler.on("log",function(msg) {
        if (msg.level === RED.log.WARN || msg.level === RED.log.ERROR) {
            sendDebug(msg);
        }
    });
    RED.log.addHandler(DebugNode.logHandler);

    function setNodeState(node,state) {
        if (state) {
            node.active = true;
        } else {
            node.active = false;
        }
    }

    RED.httpAdmin.post("/debug/:state", RED.auth.needsPermission("debug.write"), function(req,res) {
        var state = req.params.state;
        if (state !== 'enable' && state !== 'disable') {
            res.sendStatus(404);
            return;
        }
        var nodes = req.body && req.body.nodes;
        if (Array.isArray(nodes)) {
            nodes.forEach(function(id) {
                var node = RED.nodes.getNode(id);
                if (node !== null && typeof node !== "undefined" ) {
                    setNodeState(node, state === "enable");
                }
            })
            res.sendStatus(state === "enable" ? 200 : 201);
        } else {
            res.sendStatus(400);
        }
    })

    RED.httpAdmin.post("/debug/:id/:state", RED.auth.needsPermission("debug.write"), function(req,res) {
        var state = req.params.state;
        if (state !== 'enable' && state !== 'disable') {
            res.sendStatus(404);
            return;
        }
        var node = RED.nodes.getNode(req.params.id);
        if (node !== null && typeof node !== "undefined" ) {
            setNodeState(node,state === "enable");
            res.sendStatus(state === "enable" ? 200 : 201);
        } else {
            res.sendStatus(404);
        }
    });

    let cachedDebugView;
    RED.httpAdmin.get("/debug/view/view.html", function(req,res) {
        if (!cachedDebugView) {
            fs.readFile(path.join(__dirname,"lib","debug","view.html")).then(data => {
                let customStyles = "";
                try {
                    let customStyleList = RED.settings.editorTheme.page._.css || [];
                    customStyleList.forEach(style => {
                        customStyles += `<link rel="stylesheet" href="../../${style}">\n`
                    })
                } catch(err) {}
                cachedDebugView = data.toString().replace("<!-- INSERT-THEME-CSS -->",customStyles)
                res.set('Content-Type', 'text/html');
                res.send(cachedDebugView).end();
            }).catch(err => {
                res.sendStatus(404);
            })
        } else {
            res.send(cachedDebugView).end();
        }

    });

    // As debug/view/debug-utils.js is loaded via <script> tag, it won't get
    // the auth header attached. So do not use RED.auth.needsPermission here.
    RED.httpAdmin.get("/debug/view/*",function(req,res) {
        var options = {
            root: path.join(__dirname,"lib","debug"),
            dotfiles: 'deny'
        };
        try {
            res.sendFile(
                req.params[0],
                options,
                err => {
                    if (err) {
                        res.sendStatus(404);
                    }
                }
            )
        } catch(err) {
            res.sendStatus(404);
        }
    });
};