module.exports = function(RED) {
    "use strict";
    var mongo = require('mongodb');
    var ObjectID = require('mongodb').ObjectID;
    var MongoClient = mongo.MongoClient;

    function MongoNode(n) {
        RED.nodes.createNode(this, n);
        this.hostname = n.hostname;
        this.port = n.port;
        this.db = n.db;
        this.name = n.name;
        this.connectOptions= n.connectOptions;
        this.topology = n.topology;

        //console.log(this);

        var clustered = (this.topology !== "direct") || false;

        var url = "mongodb://";
        if (this.topology === "dnscluster") {
            url = "mongodb+srv://";
        }
        if (this.credentials && this.credentials.user && this.credentials.password) {
            this.user = this.credentials.user;
            this.password =  this.credentials.password;
        } else {
            this.user = n.user;
            this.password = n.password;
        }
        if (this.user) {
            url += this.user+":"+this.password+"@";
        }
        if (clustered) {
            url += this.hostname + "/" + this.db
        } else {
            url += this.hostname + ":" + this.port + "/" + this.db;
        }
        if (this.connectOptions){
            url += "?" + this.connectOptions;
        }

        console.log("MongoDB URL: " + url);
        this.url = url;
    }

    RED.nodes.registerType("mongodb", MongoNode, {
        credentials: {
            user: { type: "text" },
            password: { type: "password" }
        }
    });

    function ensureValidSelectorObject(selector) {
        if (selector != null && (typeof selector != 'object' || Buffer.isBuffer(selector))) {
            return {};
        }
        return selector;
    }

    function MongoOutNode(n) {
        RED.nodes.createNode(this, n);
        this.collection = n.collection;
        this.mongodb = n.mongodb;
        this.payonly = n.payonly || false;
        this.upsert = n.upsert || false;
        this.multi = n.multi || false;
        this.operation = n.operation;
        this.mongoConfig = RED.nodes.getNode(this.mongodb);
        this.status({fill:"grey",shape:"ring",text:RED._("mongodb.status.connecting")});
        var node = this;
        var noerror = true;

        var connectToDB = function() {
            MongoClient.connect(node.mongoConfig.url, function(err, client) {
                if (err) {
                    node.status({ fill: "red", shape: "ring", text: RED._("mongodb.status.error") });
                    if (noerror) { node.error(err); }
                    noerror = false;
                    node.tout = setTimeout(connectToDB, 10000);
                }
                else {
                    node.status({fill:"green",shape:"dot",text:RED._("mongodb.status.connected")});
                    node.clientDb = client.db();
                    var db = client.db();
                    //console.log( db);
                    noerror = true;
                    var coll;

                    if (node.collection) {
                        coll = db.collection(node.collection);
                    }
                    node.on("input", function (msg) {
                        if (!node.collection) {
                            if (msg.collection) {
                                coll = db.collection(msg.collection);
                            }
                            else {
                                node.error(RED._("mongodb.errors.nocollection"), msg);
                                return;
                            }
                        }
                        delete msg._topic;
                        delete msg.collection;
                        if (node.operation === "store") {
                            storeInDb(node, msg, coll);
                        }
                        else if (node.operation === "insert") {
                            insertInDb(node, msg, coll);
                        }
                        else if (node.operation === "update") {
                            updateInDb(node, msg, coll);
                        }
                        else if (node.operation === "delete") {
                            deleteInDb(node, msg, coll);
                        }
                    });
                }
            });
        }

        if (node.mongoConfig) { connectToDB(); }
        else { node.error(RED._("mongodb.errors.missingconfig")); }

        node.on("close", function () {
            node.status({});
            if (node.tout) { clearTimeout(node.tout); }
            if (node.clientDb) { node.clientDb.close(); }
        });
    }
    RED.nodes.registerType("mongodb out", MongoOutNode);


    function MongoInNode(n) {
        RED.nodes.createNode(this, n);
        this.collection = n.collection;
        this.mongodb = n.mongodb;
        this.payonly = n.payonly || false;
        this.upsert = n.upsert || false;
        this.multi = n.multi || false;
        this.operation = n.operation || "find";
        this.mongoConfig = RED.nodes.getNode(this.mongodb);
        this.status({ fill: "grey", shape: "ring", text: RED._("mongodb.status.connecting") });
        var node = this;
        var noerror = true;

        var connectToDB = function() {
            console.log("connecting:  " + node.mongoConfig.url);
            MongoClient.connect(node.mongoConfig.url, function(err,client) {
                if (err) {
                    node.status({ fill: "red", shape: "ring", text: RED._("mongodb.status.error") });
                    if (noerror) { node.error(err); }
                    noerror = false;
                    node.tout = setTimeout(connectToDB, 10000);
                }
                else {
                    node.status({fill:"green",shape:"dot",text:RED._("mongodb.status.connected")});
                    node.clientDb = client.db();
                    var db = client.db();
                    noerror = true;
                    var coll;
                    node.on("input", function (msg) {
                        if (!node.collection) {
                            if (msg.collection) {
                                coll = db.collection(msg.collection);
                            }
                            else {
                                node.error(RED._("mongodb.errors.nocollection"));
                                return;
                            }
                        }
                        else {
                            coll = db.collection(node.collection);
                        }
                        var selector;
                        if (node.operation === "find") {
                            msg.projection = msg.projection || {};
                            selector = ensureValidSelectorObject(msg.payload);
                            var limit = msg.limit;
                            if (typeof limit === "string" && !isNaN(limit)) {
                                limit = Number(limit);
                            } else if (typeof limit === "undefined") {
                                limit = 0;
                            }
                            var skip = msg.skip;
                            if (typeof skip === "string" && !isNaN(skip)) {
                                skip = Number(skip);
                            } else if (typeof skip === "undefined") {
                                skip = 0;
                            }

                            coll.find(selector).project(msg.projection).sort(msg.sort).limit(limit).skip(skip).toArray(function(err, items) {
                                if (err) {
                                    node.error(err);
                                    >          }
                                else {
                                    msg.payload = items;
                                    delete msg.projection;
                                    delete msg.sort;
                                    delete msg.limit;
                                    delete msg.skip;
                                    node.send(msg);
                                }
                            });
                        }
                        else if (node.operation === "count") {
                            selector = ensureValidSelectorObject(msg.payload);
                            coll.count(selector, function (err, count) {
                                if (err) {
                                    node.error(err);
                                }
                                else {
                                    msg.payload = count;
                                    node.send(msg);
                                }
                            });
                        }
                        else if (node.operation === "aggregate") {
                            msg.payload = (Array.isArray(msg.payload)) ? msg.payload : [];
                            coll.aggregate(msg.payload, function(err, cursor) {
                                if (err) {
                                    node.error(err);
                                }
                                else {
                                     cursor.toArray(function(cursorError, cursorDocs) {
                                       //console.log(cursorDocs);
                                       if (cursorError) {
                                         node.error(cursorError);
                                       }
                                       else {
                                         msg.payload = cursorDocs;
                                         node.send(msg);
                                       }
                                     });
                                }
                            });
                        }
                        else if (node.operation === "store") {
                            storeInDb(node, msg, coll);
                        }
                        else if (node.operation === "insert") {
                            insertInDb(node, msg, coll);
                        }
                        else if (node.operation === "update") {
                            updateInDb(node, msg, coll);
                        }
                        else if (node.operation === "delete") {
                            deleteInDb(node, msg, coll);
                        }
                    });
                }
            });
        }

        if (node.mongoConfig) { connectToDB(); }
        else { node.error(RED._("mongodb.errors.missingconfig")); }

        node.on("close", function () {
            node.status({});
            if (node.tout) { clearTimeout(node.tout); }
            if (node.clientDb) { node.clientDb.close(); }
        });
    }
    RED.nodes.registerType("mongodb in", MongoInNode);

    function insertInDb(node, msg, coll) {
        if (node.payonly) {
            if (typeof msg.payload !== "object") {
                msg.payload = { "payload": msg.payload };
            }
            if (msg.hasOwnProperty("_id") && !msg.payload.hasOwnProperty("_id")) {
                msg.payload._id = msg._id;
            }
            coll.insert(msg.payload, function (err, item) {
                if (err) {
                    node.error(err, msg);
                }
                else {
                    msg.payload = item;
                    node.send(msg);
                }
            });
        }
        else {
            coll.insert(msg, function (err, item) {
                if (err) {
                    node.error(err, msg);
                }
                else {
                    msg.payload = item;
                    node.send(msg);
                }
            });
        }
    }

    function updateInDb(node, msg, coll) {
        if (typeof msg.payload !== "object") {
            msg.payload = { "payload": msg.payload };
        }
        var query = msg.query || {};
        var payload = msg.payload || {};
        var options = {
            upsert: node.upsert,
            multi: node.multi
        };
        if (ObjectID.isValid(msg.query._id)) {
            msg.query._id = new ObjectID(msg.query._id);
        }
        coll.update(query, payload, options, function (err, item) {
            if (err) {
                node.error(err, msg);
            }
            else {
                msg.payload = item;
                node.send(msg);
            }
        });
    }

    function deleteInDb(node, msg, coll) {
        coll.remove(msg.payload, function (err, items) {
            if (err) {
                node.error(err, msg);
            }
            else {
                msg.payload = items;
                node.send(msg);
            }
        });
    }

    function storeInDb(node, msg, coll) {
        if (node.payonly) {
            if (typeof msg.payload !== "object") {
                msg.payload = { "payload": msg.payload };
            }
            if (msg.hasOwnProperty("_id") && !msg.payload.hasOwnProperty("_id")) {
                msg.payload._id = msg._id;
            }
            coll.save(msg.payload, function (err, item) {
                if (err) {
                    node.error(err, msg);
                }
                else {
                    msg.payload = item;
                    node.send(msg);
                }
            });
        }
        else {
            coll.save(msg, function (err, item) {
                if (err) {
                    node.error(err, msg);
                }
                else {
                    msg.payload = item;
                    node.send(msg);
                }
            });
        }
    }
}