// changed to SASS+autoprefixer using this blog post: http://ilikekillnerds.com/2016/07/adding-postcssautoprefixer-aurelia-cli/

import gulp from 'gulp';
import sourcemaps from 'gulp-sourcemaps';
import project from '../aurelia.json';
import sass from 'gulp-sass';
import postcss from 'gulp-postcss';
import cssnano from 'gulp-cssnano';
import autoprefixer from 'autoprefixer';
import lintCSS from './lint-css';
import rename from 'gulp-rename';

export default function processCSS() {
  let processors = [
    autoprefixer(project.cssProcessor.browsers)
  ];

  return gulp.src(project.cssProcessor.source)
  .pipe(lintCSS())
  .pipe(sourcemaps.init())
  .pipe(sass({
    includePaths: project.cssProcessor.sassIncludePaths
  }).on('error', sass.logError))
  .pipe(postcss(processors))
  .pipe(cssnano())
  .pipe(sourcemaps.write('.'))
  .pipe(rename(path => {
    // this means the generated css files are placed directly in assets/css folder instead of a scss sub-folder
    path.dirname = path.dirname.replace('scss', '');
  }))
  .pipe(gulp.dest(project.cssProcessor.output));
}