/* Gulp module and Plugins */
const gulp = require('gulp'),
      imagemin = require('gulp-imagemin'),
      clean = require('gulp-clean'),
      uglify = require('gulp-uglify'),
      cssmin = require('gulp-cssmin'),
      usemin = require('gulp-usemin'),
      connect = require('gulp-connect-php'),
      browserSync = require('browser-sync'),
      runSequence = require('run-sequence'),
      uncss = require('gulp-uncss'),

/* Source and Distribution path */
      workPath = 'src',
      savePath = 'dist';


/* Default task */
//clean dist -> copy src to dist ->
//build image & minify js/css ->
//remove unused css in html files ->
//start a php server and browserSync and watch
gulp.task('default', function(){
  runSequence(
    'copy',
    ['build-img', 'usemin'],
    'uncss',
    'start-server'
  );
});


/* Clean de dist folder */
gulp.task('clean', function(){
  return gulp.src(savePath)
              .pipe(clean());
});


/* Copy from src to dist */
//need clean before
gulp.task('copy', ['clean'], function(){
  return gulp.src(workPath + '/**/*')
      .pipe(gulp.dest(savePath));
});


/* Build image */
//compact them
//doesn't need to wait (synchronous)
//need copy before
gulp.task('build-img', function(){
  gulp.src(savePath + '/public/img/**/*')
      .pipe(imagemin())
      .pipe(gulp.dest(savePath + '/public/img/'));
});


/* Build JS & CSS */
//js: uses uglify plugin
//css: uses cssmin plugin
//need copy before
gulp.task('usemin', function(){
  return gulp.src(savePath + '/**/*.{html,phtml}')
      .pipe(usemin({
        'path' : savePath + '/public',
        'outputRelativePath' : 'public',
        'js' : [uglify],
        'css' : [cssmin]
      }))
      .pipe(gulp.dest(savePath));
});


/* Remove unused css in html files */
//need usemin before
gulp.task('uncss', function(){
  return gulp.src(savePath + '/public/css/**/*.css')
              .pipe(uncss({
                html : [savePath + '/app/views/**/*.{html,phtml}']
              }))
              .pipe(gulp.dest(savePath + '/public/css'));
});


/* Start a php server with dist & browserSync */
gulp.task('start-server', function(){
  //create php server
  connect.server({
    port : 8000,
    hostname : '127.0.0.1',
    base : savePath + '/public'
  }, function (){
    //start browserSync
    browserSync.init({
      proxy: '127.0.0.1:8000'
    });
  });

  //look for changes in src
  //then start browser-sync
  gulp.watch(workPath + '/**/*').on('change', function () {
    gulp.start('browser-sync');
  });
});


/* Rebuild dist & reload browser */
//called after any change on src
gulp.task('browser-sync', function(){
  return runSequence(
    'copy',
    ['build-img', 'usemin'],
    'uncss',
    'browser-reload'
  );
});


/* Reload browser */
gulp.task('browser-reload', function(){
  browserSync.reload();
});