denis-sokolov/portent

'use strict';

var browserify = require('browserify');
var gulp = require('gulp');
var gulpConcat = require('gulp-concat');
var gulpIf = require('gulp-if');
var gulpSourcemaps = require('gulp-sourcemaps');
var gulpUglify = require('gulp-uglify');
var md5 = require('md5');
var sortStream = require('sort-stream2');
var through2 = require('through2');

var expires = require('./util/expires');
var gulpStreamToString = require('./util/gulp-stream-to-string');
var getFiles = require('./util/get-files');

module.exports = function(directory, options){
    options = options || {};

    var jsDirectories = [directory + '/js'];

    var get = function(){
        return getFiles(jsDirectories, ['js']).then(function(files){
            return gulpStreamToString(gulp.src(files)
                .pipe(gulpIf(/\.cjs\.js$/, through2.obj(function (file, enc, next){
                    return browserify(file.path, {
                        debug: options.debug, fullPaths: true
                    })
                        .bundle(function(err, res){
                            if (err) return next(err);
                            file.contents = res;
                            next(null, file);
                        });
                    })))
                .pipe(sortStream(function(a, b){
                    return getFiles.sort(jsDirectories)(a.path, b.path);
                }))
                .pipe(gulpIf(options.debug, gulpSourcemaps.init({loadMaps: true})))
                .pipe(gulpConcat('compiled.js'))
                .pipe(gulpIf(!options.debug, gulpUglify({preserveComments: 'license'})))
                .pipe(gulpIf(options.debug, gulpSourcemaps.write()))
            );
        });
    };

    var getPaths = function(){
        return get().then(function(code){
            if (!code)
                return [];
            return ['scripts.' + md5(code) + '.js'];
        });
    };

    return {
        middleware: function(req, res, next){
            var send = function(codePromise){
                codePromise.then(function(code){
                    res.type('application/javascript');
                    res.set('Expires', expires());
                    res.send(code);
                }).then(null, next);
            };
            if (req.path.match(/^\/scripts\..+\.js$/))
                return send(get());
            next();
        },
        paths: getPaths,
        modifyHtml: function($, env){
            return getPaths().then(function(paths){
                return paths.map(function(path){
                    return $('<script>').attr('src', path);
                });
            }).then(env.appendToBody);
        }
    };
};