app.js

/*jshint node:true*/

console.log('[app.js] Application setup beginning.');

var Express = require('express'),
	Util = require('util'),
	Wikidot = require('./public/js/wikidot'),
	Scoring = require('./public/js/scoring'),
	Calendar = require('./public/js/calendar'),
	Timespan = require('./public/js/timespan'),
	Jasmine = require('./public/js/jasmine'),
	Recalculate = require('./public/js/recalculate'),
	Q = require('q'),
	_ = require('underscore');

// setup middleware
var app = Express();
app.use(Express.static(__dirname + '/public')); //setup static public directory
app.set('view engine', 'ejs');
app.set('views', __dirname + '/views'); //optional since express defaults to CWD/views
app.engine('html', require('ejs').renderFile);


//TODO Refactor routing definitions out to a middleware routes.js
//TODO Routes = require('./public/js/routes');
//TODO Routes.apply(app);

// render index page
app.get('/', function(request,response) {
	console.log(
		'/',
		'_songs: %s; _calendar: %s; _artists: %s',
		roughSizeOfObject(_songs),roughSizeOfObject(_calendar),roughSizeOfObject(_artists)
	);
	res.render("index.html");
});
//TODO songChart.html
app.get('/artistChart', function(request,response) {
	response.render("artistChart.html");
});


var deferred = Q.defer();

// Utility functions.

function roughSizeOfObject( object ) {

    var objectList = [];
    var stack = [ object ];
    var bytes = 0;

    while ( stack.length ) {
        var value = stack.pop();

        if ( typeof value === 'boolean' ) {
            bytes += 4;
        }
        else if ( typeof value === 'string' ) {
            bytes += value.length * 2;
        }
        else if ( typeof value === 'number' ) {
            bytes += 8;
        }
        else if
        (
            typeof value === 'object'
            && objectList.indexOf( value ) === -1
        )
        {
            objectList.push( value );

            for( var i in value ) {
                stack.push( value[ i ] );
            }
        }
    }
    return bytes;
}
function pushSong(pArray,pSlug,pSong) {
	if (pArray[pSlug]) {
		pArray[pSlug].push(pSong);
	} else {
		pArray[pSlug] = [pSong];
	}
}

// Cache the songs that have been downloaded.
var _songs = {};
var _calendar = new Calendar();
var _artists = {};

// p: { 'fullname': fullname of page to get, 'callback': function to process the received content }
function getPage(p) {
	var fullname = p.fullname;  

	Wikidot.getPage(fullname, function(error,content) {
		if (error) {
			setImmediate(getPage,p); // requeue this
			return;
		}
		p.callback(content);
	}); // Wikidot.getPage
}
			
app.get('/scores/artist/:slug', function(request,response) {
	response.json(_artists[request.params.slug]);
});

// Rank filter: All songs with projected peak at or above the given rank.
rankFn = function(someRank) { return function(song) { return parseFloat(song.peakrank) <= parseFloat(someRank); }; };
app.get('/scores/rank/:rank', function(request,response) {
	subset = _.filter(_songs, rankFn(request.params.rank));
	response.json(subset);
});

// Duration filter: All songs with projected duration at or above a given number.
durationFn = function(someAmount) { return function(song) { return parseFloat(song.months) >= parseFloat(someAmount); }; };
app.get('/scores/duration/:duration', function(request,response) {
	subset = _.filter(_songs, durationFn(request.params.duration));
	response.json(subset);
});

//TODO Generalize and add support for multiple fields.
function orderFnFn(field) {
	var sign = 1;
	if (field.substr(0,1) == "-") {
		field = field.substr(1);
		sign = -1;
	}
	return function(entity) {
		return sign*entity[field];
	}
}

app.get('/songs', function(request,response) {

	console.log('/songs',request.query);
	
	// Get post parameters.
	var decade = request.query.decade;
	var year   = request.query.year;
	var month  = request.query.month;
	var refresh = false; // disabled for now - request.query.refresh;
	var top    = request.query.top; // default: all

	orderField = request.query.sortField ? request.query.sortField : "-score";
	
	if (refresh) {
		 q = Q.fcall(getSongPageList);
	} else {
		q = Q.fcall(function() { return; } );
	}
	
	q.then(function() {
	
		content = {};
		
		//TODO Option to return highest-peaking songs.
		//TODO Option to return highest-debuting songs.
		//TODO Option to return only those songs for a particular artist.
		if (decade) {
			content = _calendar.get().byDecade(decade);
		} else if (year) {
			if (month) {
				content = _calendar.get().byMonth(year,month);
			} else {
				content = _calendar.get().byYear(year);
			}
		}
		
		//TODO Filter songs by criteria given.

		if (content) {
			content = _.sortBy(content,orderFnFn(orderField));
			for (var index in content) {
				song = content[index];
				song.rank = parseInt(index)+1;
			}
			if (top) {
				content = _.first(content,top);
			}
			console.log('Returning songs.',content.length);
		} else {
			console.log('No songs to return!');
		}

		response.json(content);
	})
	
	.catch(function (error) {
		console.log('ERROR',error);
		response.json({}); //TODO Make this more robust.
	})
	
	.done();
});

app.get('/artists', function(request,response) {
	console.log('/artists');

	var top    
		= request.query.top ? request.query.top : 100;
	var orderField 
		= request.query.sortField ? request.query.sortField : "-score";

	var refresh = false; // disabled for now - request.query.reload;
		
	if (refresh) {
		 q = Q.fcall(getSongPageList);
	} else {
		q = Q.fcall(function() { return; } );
	}
	
	q.then(function() {
	
		content = _.map(
			_artists,
			function (songArray, artistSlug) {
				return {
					slug: artistSlug,
					songCount: songArray.length,
					score: Scoring.songCollectionScore(songArray)
				};
			}
		); // _.map
		
		if (content) {
			content = _.sortBy(content,orderFnFn(orderField));
			for (var index in content) {
				entity = content[index];
				entity.rank = parseInt(index)+1;
			}
			if (top) {
				content = _.first(content,top);
			}
			console.log('Returning artists.',content.length);
		} else {
			console.log('No artists to return!');
		}

		response.json(content);
	})
	
	.catch(function (error) {
		console.log('ERROR',error);
		response.json({}); //TODO Make this more robust.
	})
	
	.done();
});

function getPagesPromise(list) {
	var promises = list.map(function(slug) {
		return Q.nfcall(Wikidot.getPage, slug);
	});
	return Q.all(promises);
}

app.get('/page/:fullname', function(request,response) {

	console.log('/page',request.params.fullname);
	
    getPagesPromise([request.params.fullname])
    .then(
		function(returnValue) { 
			response.json(returnValue[0]); // Wikidot returns an array, but angular $resource.get expects an object.
		}
	)
	.fail(function (error) {
		console.log('ERROR',error);
		response.json({}); //TODO Make this more robust.
	})
	.done();
	
});

app.get('/runJasmine', function(request,response) {
	console.log('/jasmine');
	response.json(Jasmine.run());	
});

app.get('/recalculate', Recalculate);
		

// There are many useful environment variables available in process.env.
// VCAP_APPLICATION contains useful information about a deployed application.
var appInfo = JSON.parse(process.env.VCAP_APPLICATION || "{}");
// TODO: Get application information and use it in your app.

Wikidot.username = process.env.WIKIDOT_USERNAME;
Wikidot.apiKey = process.env.WIKIDOT_APIKEY;
Wikidot.site = process.env.WIKIDOT_SITE;

// VCAP_SERVICES contains all the credentials of services bound to
// this application. For details of its content, please refer to
// the document or sample of each service.
var services = JSON.parse(process.env.VCAP_SERVICES || "{}");
// TODO: Get service credentials and communicate with bluemix services.

// Start server
// The IP address of the Cloud Foundry DEA (Droplet Execution Agent) that hosts this application:
var host = (process.env.VCAP_APP_HOST || 'localhost');
// The port on the DEA for communication with the application:
var port = (process.env.VCAP_APP_PORT || 3000);
app.listen(port, host);

// All done.
console.log('[app.js] Application setup complete.');
// ================================================================================