gulpfile.js

var gulp = require('gulp');
var replace = require('gulp-replace');
var del = require('del');
var vinylPaths = require('vinyl-paths');
var runSequence = require('run-sequence');
var shell = require('gulp-shell');
var imageResize = require('gulp-image-resize');
var rename = require("gulp-rename");

var SRC = {
	java : './src/java/*.java',
	config : './src/config/**/*',
	images : './src/image/',
	consts :  './src/const.js'
};

var BUILD = {
	android : './android/app/',
	app : './app/image',
	consts :  './app/'
};
var TYPE = {
	free : '.free',
	pro : ''
};

var NAME = {
	free : ' - Free',
	pro : '',
	domain : [ 'com' , 'myDomain' ]
};

var NAME_PATH = '/' + ( TYPE.domain.join('/') ) + '/myApp/';

function change (name){
	return function (){
		return gulp
			.src(SRC.consts)
			.pipe(replace('|*IS*|', (name == 'free').toString()))
			.pipe(replace('|*DOMAIN*|', TYPE.domain.join('.') ))
			.pipe(gulp.dest(BUILD.consts));
	}
}

function createJavas (name){
	return function (){
		return gulp
			.src(SRC.java)
			.pipe(replace('|*TYPE*|', TYPE[name] ))
			.pipe(replace('|*DOMAIN*|', TYPE.domain.join('.') ))
			.pipe(gulp.dest(BUILD.android + 'src/main/java/' + NAME_PATH + TYPE[name].replace('.', '')));
	}
}

function createConfig (name){
	return function (){
		return  gulp
			.src(SRC.config)
			.pipe(replace('|*TYPE*|', TYPE[name] ))
			.pipe(replace('|*NAME*|', NAME[name] ))
			.pipe(replace('|*DOMAIN*|', TYPE.domain.join('.') ))
			.pipe(gulp.dest(BUILD.android));
	}
}

function createImages (name){
	return function (){
		return gulp
			.src(SRC.images + name + '/*.png')  
			.pipe(gulp.dest(BUILD.app));
	}
}

function createIcons (name){
	return function (){
		return gulp
			.src( SRC.images + 'icon-' + name + '.png' )
			.pipe(rename({
				basename: "ic_launcher",
				extname: ".png"
			}))
			.pipe(imageResize({
				width : 144,
			    height : 144,
			    crop : false,
			    upscale : true
			}))
			.pipe(gulp.dest(BUILD.android + 'src/main/res/mipmap-xxhdpi/'))
			.pipe(imageResize({
				width : 96,
			    height : 96,
			    crop : false,
			    upscale : true
			}))
			.pipe(gulp.dest(BUILD.android + 'src/main/res/mipmap-xhdpi/'))
			.pipe(imageResize({
				width : 72,
			    height : 72,
			    crop : false,
			    upscale : true
			}))
			.pipe(gulp.dest(BUILD.android + 'src/main/res/mipmap-hdpi/'))
			.pipe(imageResize({
				width : 48,
			    height : 48,
			    crop : false,
			    upscale : true
			}))
			.pipe(gulp.dest(BUILD.android + 'src/main/res/mipmap-mdpi/'));
	}
}

function run (name){
	return function (cb){
		runSequence('clean',
			['java' + name, 'config' + name, 'images' + name, 'icons' + name],
			'const' + name, cb);
	}
}

function clean (name){
	return function (){
		return gulp
			.src(BUILD.android + name)
			.pipe(vinylPaths(del));
	}
}

gulp.task('constFree', change('free'));
gulp.task('constPro', change('pro'));

gulp.task('javaFree', createJavas('free'));
gulp.task('javaPro', createJavas('pro'));

gulp.task('configFree', createConfig('free'));
gulp.task('configPro', createConfig('pro'));

gulp.task('imagesFree', createImages('free'));
gulp.task('imagesPro', createImages('pro'));

gulp.task('iconsFree', createIcons('free'));
gulp.task('iconsPro', createIcons('pro'));

gulp.task('clean-images', clean('src/res/**/*.png'));
gulp.task('clean-java', clean('src/main/java/**/*.java'));

gulp.task('clean', ['clean-images', 'clean-java']);
gulp.task('apk', shell.task([ './gradlew assembleRelease' ],{ cwd : './android' }));

gulp.task('free', run('Free'));
gulp.task('default', run('Pro'));