// $Revision: 16 $ -- $Date: 2016-02-08 15:14:12 -0600 (Mon, 08 Feb 2016) $

var http = require('http');
var sys = require('util');
var fs = require('fs');
var moniFilename = 'abc';
var querystring = require('querystring');
var q = require('q');

var deferredAllDone;

http.createServer(function(req, res) {
    //debugHeaders(req);

    deferredAllDone = q.defer();
    deferredAllDone.promise.done(function(pos) {
        res.end();
        console.log("Response END. [" + pos + "]");
    });

    if (req.headers.accept && req.headers.accept === 'text/event-stream') {
        var arrMatches;
        arrMatches = req.url.match(new RegExp(/\/events\/(.*)$/));
        if (arrMatches) {
            moniFilename = arrMatches[1];
            console.log("Monitoring:" + moniFilename);
            sendSSE(req, res);
        } else {
            res.writeHead(404);
            deferredAllDone.resolve("404");
        }
    } else {
        console.log("RCV-HTML");
        res.writeHead(200, { 'Content-Type': 'text/html', 'Cache-Control': 'no-cache' ,'Access-Control-Allow-Origin': '*' });
        arrMatches = req.url.match(new RegExp(/\/(save|raw)\/(.*)$/));
        console.log("Matches", arrMatches);
        if ((arrMatches) && (arrMatches.length === 3)) {
            var func = arrMatches[1];
            moniFilename = arrMatches[2];
            if ("save" === func) {
                console.log("SAVE-Data");
                //sys.puts(sys.inspect(req));
                var fullBody = '';

                req.on('data', function(chunk) {
                    // append the current chunk of data to the fullBody variable
                    fullBody += chunk.toString();
                });

                //req.on('end', (function(res) {
                req.on('end', function() {
                    var decodedBody = querystring.parse(fullBody);
                    //sys.puts(sys.inspect(decodedBody));

                    fs.writeFile(__dirname + "/docs/" + moniFilename, decodedBody.data, function(err) {
                        if (err) {
                            res.write('ERROR : "' + err + '"');
                            deferredAllDone.resolve("OnEndERR");
                            console.log(err);
                        } else {
                            fs.stat(__dirname + "/docs/" + moniFilename, function(err, stats) {
                                if (stats) {
                                    console.log('deb' + stats.mtime);
                                    res.write(constructJSON("Saved", stats.mtime));
                                }
                                deferredAllDone.resolve("OnEndSaved");
                            });
                        }
                    });
                });
                //}(res)));
            } else if ("raw" === func) {
                console.log("RAW");
                try {
                    res.write(fs.readFileSync(__dirname + '/docs/' + moniFilename));
                } catch (e) {
		    res.writeHead(404, { 'Content-Type': 'text/html' });
                    console.log("RAW - FAILED");
                }
                deferredAllDone.resolve("OnRaw");
            }
        } else {
            var reqFile=req.url.replace("/wc/","");

            console.log("Orig Requested File " + reqFile );
            if ((reqFile!=='EventSource.js') && (reqFile!=='autosize.min.js') ) {
                reqFile='display.html'
            }
            console.log("Requested File " + reqFile );
            var contentType="text/html";
            if (reqFile.match(/\.css/gi)) {
                contentType="text/css";
            }
            if (reqFile.match(/\.js/gi)) {
                contentType="application/javascript";
            }


            var filePath = __dirname + '/' + reqFile;
            console.log("Full path " + filePath + " [" + contentType + "]"  );

            try {
		    console.log("A");
                var stat = fs.statSync(filePath);

		    console.log("B");
                var readStream = fs.createReadStream(filePath);
		    console.log("C");
                res.writeHead(200, {"Content-Type":contentType});

		    console.log("D");
                readStream.pipe(res); // this will do a res.end() by its own.
		    console.log("E");

            } catch (ex) {
                res.writeHead(404,{"Content-Type":"text/html"});
                res.write("Not found: " + reqFile );
                deferredAllDone.resolve("OnDisplay");
                console.log ("Not found: " + reqFile, ex);
            }
        }
    }
}).listen(8001,'0.0.0.0');
console.log("server started.");
console.log(__dirname);

// Send the server side event - consider that this response never ends, so no res.end() is called whatsowever!
function sendSSE(req, res) {
	var theClient=req.socket.remoteAddress + ":" + req.socket.remotePort;
    res.writeHead(200, {
        'Content-Type': 'text/event-stream',
        'Cache-Control': 'no-cache',
        'Connection': 'keep-alive'
    });

    var id = (new Date()).toLocaleTimeString();

    fs.stat(__dirname + "/docs/" + moniFilename, function(err, stats) {
        if (stats) {
            console.log('deb' + stats.mtime);
            res.write(constructSSE("Modified", stats.mtime));
        }
    });

		// Watching directory for changes
		fs.watch(__dirname + '/docs/', function(event, filename) {
		console.log('event is: ' + event);
		if (filename) {
			console.log('filename provided: ' + filename);
			console.log("Monitoring:" + moniFilename);

			if (moniFilename === filename) {
				fs.stat(__dirname + "/docs/" + filename, function(err, stats) {
					console.log('deb 2 ' +theClient + " - " + stats.mtime);
					res.write(constructSSE("Modified", stats.mtime));
				});
			}
		} else {
			console.log('filename not provided');
		}
		});

}



// the SSE requires a "data" element
function constructSSE(type, timeStamp) {
    var retVal = "data: " + constructJSON(type, timeStamp) + "\n\n";
    console.log('MESSAGE-DEBUG-L: ' + type + " _ " + timeStamp);
    return (retVal);
}

// just the JSON of the data
function constructJSON(type, timeStamp) {
    var retVal = '{"type": "' + type + '",';
    retVal += ('"timeStamp": "' + timeStamp + '"}');
    return (retVal);
}

function debugHeaders(req) {
    sys.puts('URL: ' + req.url);
    for (var key in req.headers) {
        sys.puts(key + ': ' + req.headers[key]);
    }
    sys.puts('\n\n');
}