/**
 * Copyright 2013,2015 IBM Corp.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/

module.exports = function(RED) {
    "use strict";
    var http = require("follow-redirects").http;
    var https = require("follow-redirects").https;
    var urllib = require("url");
    var bodyParser = require("body-parser");
    var getBody = require('raw-body');
    var mustache = require("mustache");
    var querystring = require("querystring");
    var cors = require('cors');
    var jsonParser = bodyParser.json();
    var urlencParser = bodyParser.urlencoded({extended:true});
    var onHeaders = require('on-headers');
    var typer = require('media-typer');
    var isUtf8 = require('is-utf8');

    function rawBodyParser(req, res, next) {
        if (req._body) { return next(); }
        req.body = "";
        req._body = true;

        var isText = true;
        var checkUTF = false;

        if (req.headers['content-type']) {
            var parsedType = typer.parse(req.headers['content-type'])
            if (parsedType.type === "text") {
                isText = true;
            } else if (parsedType.subtype === "xml" || parsedType.suffix === "xml") {
                isText = true;
            } else if (parsedType.type !== "application") {
                isText = false;
            } else if (parsedType.subtype !== "octet-stream") {
                checkUTF = true;
            }
        }

        getBody(req, {
            length: req.headers['content-length'],
            encoding: isText ? "utf8" : null
        }, function (err, buf) {
            if (err) { return next(err); }
            if (!isText && checkUTF && isUtf8(buf)) {
                buf = buf.toString()
            }

            req.body = buf;
            next();
        });
    }

    var corsSetup = false;


    function createRequestWrapper(node,req) {
        var wrapper = {
            _req: req
        };
        var toWrap = [
            "param",
            "get",
            "is",
            "acceptsCharset",
            "acceptsLanguage",
            "app",
            "baseUrl",
            "body",
            "cookies",
            "fresh",
            "hostname",
            "ip",
            "ips",
            "originalUrl",
            "params",
            "path",
            "protocol",
            "query",
            "route",
            "secure",
            "signedCookies",
            "stale",
            "subdomains",
            "xhr",
            "socket" // TODO: tidy this up
        ];
        toWrap.forEach(function(f) {
            if (typeof req[f] === "function") {
                wrapper[f] = function() {
                    node.warn(RED._("httpin.errors.deprecated-call",{method:"msg.req."+f}));
                    var result = req[f].apply(req,arguments);
                    if (result === res) {
                        return wrapper;
                    } else {
                        return result;
                    }
                }
            } else {
                wrapper[f] = req[f];
            }
        });


        return wrapper;
    }
    function createResponseWrapper(node,res) {
        var wrapper = {
            _res: res
        };
        var toWrap = [
            "append",
            "attachment",
            "cookie",
            "clearCookie",
            "download",
            "end",
            "format",
            "get",
            "json",
            "jsonp",
            "links",
            "location",
            "redirect",
            "render",
            "send",
            "sendfile",
            "sendFile",
            "sendStatus",
            "set",
            "status",
            "type",
            "vary"
        ];
        toWrap.forEach(function(f) {
            wrapper[f] = function() {
                node.warn(RED._("httpin.errors.deprecated-call",{method:"msg.res."+f}));
                var result = res[f].apply(res,arguments);
                if (result === res) {
                    return wrapper;
                } else {
                    return result;
                }
            }
        });
        return wrapper;
    }

    function HTTPIn(n) {
        RED.nodes.createNode(this,n);
        if (RED.settings.httpNodeRoot !== false) {

            if (!n.url) {
                this.warn(RED._("httpin.errors.missing-path"));
                return;
            }
            this.url = n.url;
            this.method = n.method;
            this.swaggerDoc = n.swaggerDoc;

            var node = this;

            this.errorHandler = function(err,req,res,next) {
                node.warn(err);
                res.sendStatus(500);
            };

            this.callback = function(req,res) {
                var msgid = RED.util.generateId();
                res._msgid = msgid;
                if (node.method.match(/(^post$|^delete$|^put$|^options$)/)) {
                    node.send({_msgid:msgid,req:req,res:createResponseWrapper(node,res),payload:req.body});
                } else if (node.method == "get") {
                    node.send({_msgid:msgid,req:req,res:createResponseWrapper(node,res),payload:req.query});
                } else {
                    node.send({_msgid:msgid,req:req,res:createResponseWrapper(node,res)});
                }
            };

            var corsHandler = function(req,res,next) { next(); }

            if (RED.settings.httpNodeCors && !corsSetup) {
                corsHandler = cors(RED.settings.httpNodeCors);
                RED.httpNode.options("*",corsHandler);
                corsSetup = true;
            }

            var httpMiddleware = function(req,res,next) { next(); }

            if (RED.settings.httpNodeMiddleware) {
                if (typeof RED.settings.httpNodeMiddleware === "function") {
                    httpMiddleware = RED.settings.httpNodeMiddleware;
                }
            }

            var metricsHandler = function(req,res,next) { next(); }

            if (this.metric()) {
                metricsHandler = function(req, res, next) {
                    var startAt = process.hrtime();
                    onHeaders(res, function() {
                        if (res._msgid) {
                            var diff = process.hrtime(startAt);
                            var ms = diff[0] * 1e3 + diff[1] * 1e-6;
                            var metricResponseTime = ms.toFixed(3);
                            var metricContentLength = res._headers["content-length"];
                            //assuming that _id has been set for res._metrics in HttpOut node!
                            node.metric("response.time.millis", {_msgid:res._msgid} , metricResponseTime);
                            node.metric("response.content-length.bytes", {_msgid:res._msgid} , metricContentLength);
                        }
                    });
                    next();
                };
            }

            if (this.method == "get") {
                RED.httpNode.get(this.url,httpMiddleware,corsHandler,metricsHandler,this.callback,this.errorHandler);
            } else if (this.method == "post") {
                RED.httpNode.post(this.url,httpMiddleware,corsHandler,metricsHandler,jsonParser,urlencParser,rawBodyParser,this.callback,this.errorHandler);
            } else if (this.method == "put") {
                RED.httpNode.put(this.url,httpMiddleware,corsHandler,metricsHandler,jsonParser,urlencParser,rawBodyParser,this.callback,this.errorHandler);
            } else if (this.method == "delete") {
                RED.httpNode.delete(this.url,httpMiddleware,corsHandler,metricsHandler,jsonParser,urlencParser,rawBodyParser,this.callback,this.errorHandler);
            }

            this.on("close",function() {
                var node = this;
                RED.httpNode._router.stack.forEach(function(route,i,routes) {
                    if (route.route && route.route.path === node.url && route.route.methods[node.method]) {
                        routes.splice(i,1);
                    }
                });
            });
        } else {
            this.warn(RED._("httpin.errors.not-created"));
        }
    }
    RED.nodes.registerType("http in",HTTPIn);


    function HTTPOut(n) {
        RED.nodes.createNode(this,n);
        var node = this;
        this.on("input",function(msg) {
            if (msg.res) {
                if (msg.headers) {
                    msg.res._res.set(msg.headers);
                }
                var statusCode = msg.statusCode || 200;
                if (typeof msg.payload == "object" && !Buffer.isBuffer(msg.payload)) {
                    msg.res._res.status(statusCode).jsonp(msg.payload);
                } else {
                    if (msg.res._res.get('content-length') == null) {
                        var len;
                        if (msg.payload == null) {
                            len = 0;
                        } else if (Buffer.isBuffer(msg.payload)) {
                            len = msg.payload.length;
                        } else if (typeof msg.payload == "number") {
                            len = Buffer.byteLength(""+msg.payload);
                        } else {
                            len = Buffer.byteLength(msg.payload);
                        }
                        msg.res._res.set('content-length', len);
                    }

                    msg.res._res.status(statusCode).send(msg.payload);
                }
            } else {
                node.warn(RED._("httpin.errors.no-response"));
            }
        });
    }
    RED.nodes.registerType("http response",HTTPOut);


    function HTTPRequest(n) {
        RED.nodes.createNode(this,n);
        var nodeUrl = n.url;
        var isTemplatedUrl = (nodeUrl||"").indexOf("{{") != -1;
        var nodeMethod = n.method || "GET";
        this.ret = n.ret || "txt";
        var node = this;

        var prox, noprox;
        if (process.env.http_proxy != null) { prox = process.env.http_proxy; }
        if (process.env.HTTP_PROXY != null) { prox = process.env.HTTP_PROXY; }
        if (process.env.no_proxy != null) { noprox = process.env.no_proxy.split(","); }
        if (process.env.NO_PROXY != null) { noprox = process.env.NO_PROXY.split(","); }

        this.on("input",function(msg) {
            var preRequestTimestamp = process.hrtime();
            node.status({fill:"blue",shape:"dot",text:"httpin.status.requesting"});
            var url = nodeUrl || msg.url;
            if (msg.url && nodeUrl && (nodeUrl !== msg.url)) {  // revert change below when warning is finally removed
                node.warn(RED._("common.errors.nooverride"));
            }
            if (isTemplatedUrl) {
                url = mustache.render(nodeUrl,msg);
            }
            if (!url) {
                node.error(RED._("httpin.errors.no-url"),msg);
                return;
            }
            // url must start http:// or https:// so assume http:// if not set
            if (!((url.indexOf("http://") === 0) || (url.indexOf("https://") === 0))) {
                url = "http://"+url;
            }

            var method = nodeMethod.toUpperCase() || "GET";
            if (msg.method && n.method && (n.method !== "use")) {     // warn if override option not set
                node.warn(RED._("common.errors.nooverride"));
            }
            if (msg.method && n.method && (n.method === "use")) {
                method = msg.method.toUpperCase();          // use the msg parameter
            }
            var opts = urllib.parse(url);
            opts.method = method;
            opts.headers = {};
            if (msg.headers) {
                for (var v in msg.headers) {
                    if (msg.headers.hasOwnProperty(v)) {
                        var name = v.toLowerCase();
                        if (name !== "content-type" && name !== "content-length") {
                            // only normalise the known headers used later in this
                            // function. Otherwise leave them alone.
                            name = v;
                        }
                        opts.headers[name] = msg.headers[v];
                    }
                }
            }
            if (this.credentials && this.credentials.user) {
                opts.auth = this.credentials.user+":"+(this.credentials.password||"");
            }
            var payload = null;

            if (msg.payload && (method == "POST" || method == "PUT" || method == "PATCH" ) ) {
                if (typeof msg.payload === "string" || Buffer.isBuffer(msg.payload)) {
                    payload = msg.payload;
                } else if (typeof msg.payload == "number") {
                    payload = msg.payload+"";
                } else {
                    if (opts.headers['content-type'] == 'application/x-www-form-urlencoded') {
                        payload = querystring.stringify(msg.payload);
                    } else {
                        payload = JSON.stringify(msg.payload);
                        if (opts.headers['content-type'] == null) {
                            opts.headers['content-type'] = "application/json";
                        }
                    }
                }
                if (opts.headers['content-length'] == null) {
                    if (Buffer.isBuffer(payload)) {
                        opts.headers['content-length'] = payload.length;
                    } else {
                        opts.headers['content-length'] = Buffer.byteLength(payload);
                    }
                }
            }
            var urltotest = url;
            var noproxy;
            if (noprox) {
                for (var i in noprox) {
                    if (url.indexOf(noprox[i]) !== -1) { noproxy=true; }
                }
            }
            if (prox && !noproxy) {
                var match = prox.match(/^(http:\/\/)?(.+)?:([0-9]+)?/i);
                if (match) {
                    //opts.protocol = "http:";
                    //opts.host = opts.hostname = match[2];
                    //opts.port = (match[3] != null ? match[3] : 80);
                    opts.headers['Host'] = opts.host;
                    var heads = opts.headers;
                    var path = opts.pathname = opts.href;
                    opts = urllib.parse(prox);
                    opts.path = opts.pathname = path;
                    opts.headers = heads;
                    opts.method = method;
                    //console.log(opts);
                    urltotest = match[0];
                }
                else { node.warn("Bad proxy url: "+process.env.http_proxy); }
            }
            var req = ((/^https/.test(urltotest))?https:http).request(opts,function(res) {
                (node.ret === "bin") ? res.setEncoding('binary') : res.setEncoding('utf8');
                msg.statusCode = res.statusCode;
                msg.headers = res.headers;
                msg.payload = "";
                // msg.url = url;   // revert when warning above finally removed
                res.on('data',function(chunk) {
                    msg.payload += chunk;
                });
                res.on('end',function() {
                    if (node.metric()) {
                        // Calculate request time
                        var diff = process.hrtime(preRequestTimestamp);
                        var ms = diff[0] * 1e3 + diff[1] * 1e-6;
                        var metricRequestDurationMillis = ms.toFixed(3);
                        node.metric("duration.millis", msg, metricRequestDurationMillis);
                        if (res.client && res.client.bytesRead) {
                            node.metric("size.bytes", msg, res.client.bytesRead);
                        }
                    }
                    if (node.ret === "bin") {
                        msg.payload = new Buffer(msg.payload,"binary");
                    }
                    else if (node.ret === "obj") {
                        try { msg.payload = JSON.parse(msg.payload); }
                        catch(e) { node.warn(RED._("httpin.errors.json-error")); }
                    }
                    node.send(msg);
                    node.status({});
                });
            });
            req.on('error',function(err) {
                msg.payload = err.toString() + " : " + url;
                msg.statusCode = err.code;
                node.send(msg);
                node.status({fill:"red",shape:"ring",text:err.code});
            });
            if (payload) {
                req.write(payload);
            }
            req.end();
        });
    }

    RED.nodes.registerType("http request",HTTPRequest,{
        credentials: {
            user: {type:"text"},
            password: {type: "password"}
        }
    });
}