require_relative '../lib'

class VueCreate
  def initialize
    @input = InputLoop.new
    @pwd = FileUtils.pwd
    @root = ::Rails.root
    @pack = @root.join('package.json')
    @src_dir = Pathname.new(__FILE__).dirname.join('..', '..', 'source')
  end

  def self.run!
    new.start
  end

  def start
    check_node!
    FileUtils.chdir @root
    begin
      package_manager?
      install_vue_cli
      run_vue_create?
      install_dev_deps
      delete_vue_src?
      copy_demo?
      copy_config
      generate_vue_yml
      puts 'vue:create finished!'
    ensure
      FileUtils.chdir @pwd
    end
  end

  private

  def check_node!
    @pm = VueCli::Rails::NodeEnv.new
    abort('Cannot find node.js') unless @pm.node?
  end

  def package_manager?
    yarn = @pm.yarn_version
    npm = @pm.npm_version
    abort('Cannot find npm or yarn') unless yarn || npm

    if yarn && npm
      input = @input.gets(
        'Which package manager to use?',
        @root.join('package-lock.json').exist? ? 'yN' : 'Yn',
        y: 'yarn', n: 'npm',
      )
    else
      input = npm ? 'n' : 'y'
    end
    @pm.use!(input == 'n' ? :npm : :yarn)
    puts "Using package manager: #{@pm.package_manager}"
  end

  def install_vue_cli
    return if @pm.vue?

    puts "@vue/cli haven't been installed"
    pm.global_add('@vue/cli')
  end

  def run_vue_create?
    input = 'y'
    if @pack.exist?
      puts 'Detected `package.json`!'
      input = @input.gets(
        '  Do you want `vue create?` to overwrite your package.json',
        'ynAk',
        a: 'Auto', k: 'Keep',
      )
    end
    return if input == 'n'

    src_json = JSON.parse(@pack.read) unless input == 'y'
    @pm.exec('vue create', '', "-n -m #{@pm.package_manager} .")

    dst_json = JSON.parse(@pack.read) unless input == 'y'
    return if input == 'y' || dst_json == src_json

    src_json, dst_json = [dst_json, src_json] if input == 'a'
    dst_json.deep_merge!(src_json)
    @pack.write(JSON.pretty_generate(dst_json))
    @pm.install
  end

  def install_dev_deps
    package = JSON.parse(@pack.read)
    dev_deps = package['devDependencies']
    dd = %w[webpack-assets-manifest js-yaml].find_all do |dep|
      !dev_deps.key?(dep)
    end
    @pm.add "-D #{dd.join(' ')}" if dd.any?
  end

  def delete_vue_src?
    src = @root.join('src')
    return unless src.exist? && src.directory?

    puts 'Detected `src` folder (should be generated by vue-cli)'
    FileUtils.rm_rf(src.to_s) if @input.gets('  Do you want to delete src folder?') == 'y'
  end

  def copy_demo?
    return unless @input.gets('Do you want to copy demo code?', 'yN') == 'y'

    FileUtils.cp_r(@src_dir.join('app'), @root)
    routes = @root.join('config', 'routes.rb')
    return unless routes.exist?

    route_lines = routes.read.split("\n")
    foo = false
    bar = false
    route_lines.each do |line|
      foo ||= line.include? 'vue#foo'
      bar ||= line.include? 'vue#bar'
    end
    return if foo && bar

    end_line = route_lines.rindex { |ln| ln =~ /^\s*end\b/ }
    return if end_line.blank?

    route_lines.insert(end_line, "  get 'vue/bar' => 'vue#bar'") unless bar
    route_lines.insert(end_line, "  get 'vue/foo' => 'vue#foo'") unless foo
    route_lines.insert(end_line, '  # Example of vue_cli-rails')
    routes.write(route_lines.join("\n"))
  end

  def copy_config
    puts 'Copying configuration files...'
    FileUtils.cp(@src_dir.join('vue.rails.js'), "#{@root}/")
    if @root.join('vue.config.js').exist?
      puts 'Detected `vue.config.js`!'
      return if @input.gets('  Do you want to overwrite vue.config.js?', 'yN') == 'n'
    end
    FileUtils.cp(@src_dir.join('vue.config.js'), "#{@root}/")
  end

  def generate_vue_yml
    yml_dest = @root.join('config', 'vue.yml')
    if yml_dest.exist?
      puts 'Detected `config/vue.yml`!'
      return if @input.gets('  Do you want to overwrite config/vue.yml?') == 'n'
    end

    yml = @src_dir.join('vue.yml').read
    yml = yml.sub('${PACKAGE_MANAGER}', pm.package_manager.to_s)
    yml_dest.write(yml)
  end
end