'use strict';

const fs = require('fs');
const gulp = require('gulp');
const _less = require('less');
const less = require('gulp-less');
const sourcemaps = require('gulp-sourcemaps');
const rename = require('gulp-rename');
const mkdirp = require('mkdirp');

const postcss = require('gulp-postcss');
const autoprefixer = require('autoprefixer');

const config = require('../config').less;

const suffix = '-' + Date.now().toString(16);

const errorHandler = require('../util/error-handler');

_less.functions.functionRegistry.addMultiple(config.functions);

const processors = [
  autoprefixer(config.autoprefixer),
];

if (ENV === 'production') {
  const csswring = require('csswring');
  processors.push(csswring(config.csswring));
}

gulp.task('less', function () {
  mkdirp(config.dest);

  if (config.suffix)
    fs.writeFile(config.dest + '.json', JSON.stringify({ suffix }));

  let pipe = gulp.src(config.src)
    .pipe(sourcemaps.init())
    .pipe(less(config.options).on('error', errorHandler))
    .pipe(postcss(processors));

  if (config.suffix)
    pipe = pipe.pipe(rename({ suffix }));

  return pipe.pipe(sourcemaps.write('./maps'))
    .pipe(gulp.dest(config.dest));
});