var watchify = require('watchify')
var browserify = require('browserify')
var babelify = require('babelify')
var gulp = require('gulp')
var source = require('vinyl-source-stream')
var buffer = require('vinyl-buffer')
var gutil = require('gulp-util')
var watch = require('gulp-watch')
var sourcemaps = require('gulp-sourcemaps')
var jsoneditor = require('gulp-json-editor')
var zip = require('gulp-zip')
var assign = require('lodash.assign')
var livereload = require('gulp-livereload')
var brfs = require('gulp-brfs')
var del = require('del')
var eslint = require('gulp-eslint')
var fs = require('fs')
var path = require('path')
var manifest = require('./app/manifest.json')
var gulpif = require('gulp-if')
var replace = require('gulp-replace')
var disclaimer = fs.readFileSync(path.join(__dirname, 'USER_AGREEMENT.md')).toString()
var crypto = require('crypto')
var hash = crypto.createHash('sha256')

hash.update(disclaimer)
var tosHash = hash.digest('hex')

var disableLiveReload = gutil.env.disableLiveReload
var debug = gutil.env.debug

// browser reload

gulp.task('dev:reload', function() {
  livereload.listen({
    port: 35729,
    // basePath: './dist/firefox/'
  })
})


// copy static

gulp.task('copy:locales', copyTask({
  source: './app/_locales/',
  destinations: [
    './dist/firefox/_locales',
    './dist/chrome/_locales',
    './dist/edge/_locales',
  ]
}))
gulp.task('copy:images', copyTask({
  source: './app/images/',
  destinations: [
    './dist/firefox/images',
    './dist/chrome/images',
    './dist/edge/images',
  ],
}))
gulp.task('copy:fonts', copyTask({
  source: './app/fonts/',
  destinations: [
    './dist/firefox/fonts',
    './dist/chrome/fonts',
    './dist/edge/fonts',
  ],
}))
gulp.task('copy:reload', copyTask({
  source: './app/scripts/',
  destinations: [
    './dist/firefox/scripts',
    './dist/chrome/scripts',
    './dist/edge/scripts',
  ],
  pattern: '/chromereload.js',
}))
gulp.task('copy:root', copyTask({
  source: './app/',
  destinations: [
    './dist/firefox',
    './dist/chrome',
    './dist/edge',
  ],
  pattern: '/*',
}))

gulp.task('manifest:chrome', function() {
  return gulp.src('./dist/chrome/manifest.json')
  .pipe(jsoneditor(function(json) {
    delete json.applications
    return json
  }))
  .pipe(gulp.dest('./dist/chrome', { overwrite: true }))
})

gulp.task('manifest:production', function() {
  return gulp.src([
    './dist/firefox/manifest.json',
    './dist/chrome/manifest.json',
    './dist/edge/manifest.json',
  ],{base: './dist/'})
  .pipe(gulpif(disableLiveReload,jsoneditor(function(json) {
    json.background.scripts = ["scripts/background.js"]
    return json
  })))
  .pipe(gulp.dest('./dist/', { overwrite: true }))
})

const staticFiles = [
  'locales',
  'images',
  'fonts',
  'root'
]

var copyStrings = staticFiles.map(staticFile => `copy:${staticFile}`)

if (!disableLiveReload) {
  copyStrings.push('copy:reload')
}

gulp.task('copy', gulp.series(gulp.parallel(...copyStrings), 'manifest:production', 'manifest:chrome'))
gulp.task('copy:watch', function(){
  gulp.watch(['./app/{_locales,images}/*', './app/scripts/chromereload.js', './app/*.{html,json}'], gulp.series('copy'))
})

// lint js

gulp.task('lint', function () {
  // Ignoring node_modules, dist/firefox, and docs folders:
  return gulp.src(['app/**/*.js', 'ui/**/*.js', '!node_modules/**', '!dist/firefox/**', '!docs/**', '!app/scripts/chromereload.js'])
    .pipe(eslint(fs.readFileSync(path.join(__dirname, '.eslintrc'))))
    // eslint.format() outputs the lint results to the console.
    // Alternatively use eslint.formatEach() (see Docs).
    .pipe(eslint.format())
    // To have the process exit with an error code (1) on
    // lint error, return the stream and pipe to failAfterError last.
    .pipe(eslint.failAfterError())
});

/*
gulp.task('default', ['lint'], function () {
    // This will only run if the lint task is successful...
});
*/

// build js

const jsFiles = [
  'inpage',
  'contentscript',
  'background',
  'popup',
]

var jsDevStrings = jsFiles.map(jsFile => `dev:js:${jsFile}`)
var jsBuildStrings = jsFiles.map(jsFile => `build:js:${jsFile}`)

jsFiles.forEach((jsFile) => {
  gulp.task(`dev:js:${jsFile}`, bundleTask({ watch: true, filename: `${jsFile}.js` }))
  gulp.task(`build:js:${jsFile}`, bundleTask({ watch: false, filename: `${jsFile}.js` }))
})

gulp.task('dev:js', gulp.parallel(...jsDevStrings))

gulp.task('build:js',  gulp.parallel(...jsBuildStrings))


// clean dist


gulp.task('clean', function clean() {
  return del(['./dist/*'])
})

// zip tasks for distribution
gulp.task('zip:chrome', () => {
  return gulp.src('dist/chrome/**')
  .pipe(zip(`metamask-chrome-${manifest.version}.zip`))
  .pipe(gulp.dest('builds'));
})
gulp.task('zip:firefox', () => {
  return gulp.src('dist/firefox/**')
  .pipe(zip(`metamask-firefox-${manifest.version}.zip`))
  .pipe(gulp.dest('builds'));
})
gulp.task('zip:edge', () => {
  return gulp.src('dist/edge/**')
  .pipe(zip(`metamask-edge-${manifest.version}.zip`))
  .pipe(gulp.dest('builds'));
})
gulp.task('zip', gulp.parallel('zip:chrome', 'zip:firefox', 'zip:edge'))

// high level tasks

gulp.task('dev', gulp.series('dev:js', 'copy', gulp.parallel('copy:watch', 'dev:reload')))

gulp.task('build', gulp.series('clean', gulp.parallel('build:js', 'copy')))
gulp.task('dist', gulp.series('build', 'zip'))

// task generators

function copyTask(opts){
  var source = opts.source
  var destination = opts.destination
  var destinations = opts.destinations || [ destination ]
  var pattern = opts.pattern || '/**/*'

  return performCopy

  function performCopy(){
    let stream = gulp.src(source + pattern, { base: source })
    destinations.forEach(function(destination) {
      stream = stream.pipe(gulp.dest(destination))
    })
    stream.pipe(gulpif(!disableLiveReload,livereload()))

    return stream
  }
}

function bundleTask(opts) {
  var browserifyOpts = assign({}, watchify.args, {
    entries: ['./app/scripts/'+opts.filename],
    debug: true,
    plugin: 'browserify-derequire',
  })

  var bundler = browserify(browserifyOpts)
  bundler.transform(babelify.configure({
    presets: ['es2015'],
  }))
  bundler.transform('brfs')
  if (opts.watch) {
    bundler = watchify(bundler)
    bundler.on('update', performBundle) // on any dep update, runs the bundler
  }

  bundler.on('log', gutil.log) // output build logs to terminal

  return performBundle

  function performBundle(){
    return (

      bundler.bundle()
      // log errors if they happen
      .on('error', gutil.log.bind(gutil, 'Browserify Error'))
      .pipe(source(opts.filename))
      .pipe(brfs())
      .pipe(replace('GULP_TOS_HASH', tosHash))
      .pipe(replace('\'GULP_METAMASK_DEBUG\'', debug))
      // optional, remove if you don't need to buffer file contents
      .pipe(buffer())
      // optional, remove if you dont want sourcemaps
      .pipe(sourcemaps.init({loadMaps: true})) // loads map from browserify file
      // Add transformation tasks to the pipeline here.
      .pipe(sourcemaps.write('./')) // writes .map file
      .pipe(gulp.dest('./dist/firefox/scripts'))
      .pipe(gulp.dest('./dist/chrome/scripts'))
      .pipe(gulp.dest('./dist/edge/scripts'))
      .pipe(gulpif(!disableLiveReload,livereload()))

    )
  }
}