// Load in dependencies
var gulp = require('gulp');
var merge = require('merge-stream');
var through2 = require('through2');
var spritesmith = require('../');

// Define our test tasks
var images = [
  'test-files/sprite1.png',
  'test-files/sprite2.png',
  'test-files/sprite3.png'
];
var retinaImages = [
  'test-files/sprite1.png',
  'test-files/sprite1@2x.png',
  'test-files/sprite2.png',
  'test-files/sprite2@2x.png',
  'test-files/sprite3.png',
  'test-files/sprite3@2x.png'
];
gulp.task('sprite-default', function () {
  return gulp.src(images).pipe(spritesmith({
    imgName: 'sprite.png',
    cssName: 'sprite.css'
  }))
  .pipe(gulp.dest('actual-files/default/'));
});

gulp.task('sprite-retina', function () {
  return gulp.src(retinaImages).pipe(spritesmith({
    retinaSrcFilter: 'test-files/*@2x.png',
    imgName: 'sprite.png',
    retinaImgName: 'sprite@2x.png',
    cssName: 'sprite.css'
  }))
  .pipe(gulp.dest('actual-files/retina/'));
});

gulp.task('sprite-two-streams', function () {
  var data = gulp.src(images).pipe(spritesmith({
    imgName: 'sprite.png',
    cssName: 'sprite.css'
  }));
  var imgStream = data.img.pipe(gulp.dest('actual-files/two-streams/'));
  var cssStream = data.css.pipe(gulp.dest('actual-files/two-streams/'));
  return merge(imgStream, cssStream);
});

gulp.task('sprite-retina-two-streams', function () {
  var data = gulp.src(retinaImages).pipe(spritesmith({
    retinaSrcFilter: 'test-files/*@2x.png',
    imgName: 'sprite.png',
    retinaImgName: 'sprite@2x.png',
    cssName: 'sprite.css'
  }));
  var imgStream = data.img.pipe(gulp.dest('actual-files/retina-two-streams/'));
  var cssStream = data.css.pipe(gulp.dest('actual-files/retina-two-streams/'));
  return merge(imgStream, cssStream);
});

gulp.task('sprite-formats', function () {
  return gulp.src(images, {read: false}).pipe(spritesmith({
    imgName: 'sprite.jpg',
    cssName: 'sprite.css',
    imgOpts: {
      format: 'png'
    },
    cssFormat: 'stylus',
    engine: 'phantomjssmith',
    // Use `top-down` for easier testing
    algorithm: 'top-down'
  }))
  .pipe(gulp.dest('actual-files/formats/'));
});

gulp.task('sprite-options', function () {
  return gulp.src(images).pipe(spritesmith({
    imgName: 'sprite.png',
    cssName: 'sprite.css',
    imgPath: '../../everywhere.png',
    algorithm: 'alt-diagonal'
  }))
  .pipe(gulp.dest('actual-files/options/'));
});

gulp.task('sprite-template', function () {
  return gulp.src(images).pipe(spritesmith({
    imgName: 'sprite.png',
    cssName: 'sprite.scss',
    cssTemplate: 'test-files/scss.template.handlebars',
    // Use `top-down` for easier testing
    algorithm: 'top-down'
  }))
  .pipe(gulp.dest('actual-files/template/'));
});

gulp.task('sprite-spritesheet-name', function () {
  return gulp.src(images).pipe(spritesmith({
    imgName: 'sprite.png',
    cssName: 'sprite.scss',
    cssSpritesheetName: 'icons',
    // Use `top-down` for easier testing
    algorithm: 'top-down'
  }))
  .pipe(gulp.dest('actual-files/spritesheet-name/'));
});

gulp.task('sprite-retina-mapped', function () {
  return gulp.src(retinaImages).pipe(spritesmith({
    retinaSrcFilter: 'test-files/*@2x.png',
    imgName: 'sprite.png',
    retinaImgName: 'sprite@2x.png',
    cssName: 'sprite.scss',
    cssSpritesheetName: 'icons',
    cssVarMap: function (sprite) {
      // Rename `sprite` to `icon` (e.g. `sprite1` -> `icon1`)
      sprite.name = sprite.name.replace('sprite', 'icon');
    },
    cssRetinaSpritesheetName: 'retina-icons',
    cssRetinaGroupsName: 'icon-groups',
    // Use `top-down` for easier testing
    algorithm: 'top-down'
  }))
  .pipe(gulp.dest('actual-files/retina-mapped/'));
});

gulp.task('sprite-empty', function () {
  return gulp.src(images).pipe(through2.obj(
    // On data, do nothing and callback
    function onEmptyData (file, encoding, cb) {
      cb();
    },
    // On end, callback with nothing
    function onEmptyEnd (cb) {
      cb();
    }
  )).pipe(spritesmith({
    imgName: 'sprite.png',
    cssName: 'sprite.scss'
  }))
  .pipe(gulp.dest('actual-files/empty/'));
});