# frozen_string_literal: true

require "decidim/gem_manager"

namespace :decidim do
  namespace :webpacker do
    desc "Installs Decidim webpacker files in Rails instance application"
    task install: :environment do
      raise "Decidim gem is not installed" if decidim_path.nil?

      # Removing bin/yarn makes assets:precompile task to do not execute `yarn install`
      remove_file_from_application "bin/yarn"
      remove_file_from_application "yarn.lock"
      remove_file_from_application "node_modules/.yarn-integrity"
      # PostCSS configuration
      copy_file_to_application "decidim-core/lib/decidim/webpacker/postcss.config.js", "postcss.config.js"

      copy_file_to_application "decidim-core/lib/decidim/webpacker/esbuild.config.js", "config/esbuild.config.js"
      copy_file_to_application "decidim-core/lib/decidim/webpacker/tsconfig.json", "tsconfig.json"

      # Remove the Webpacker config and deploy shakapacker
      migrate_shakapacker

      # Install JS dependencies
      install_decidim_npm

      # Remove the webpacker dependencies as they come through Decidim dependencies.
      # This ensures we can control their versions from Decidim dependencies to avoid version conflicts.
      webpacker_packages = %w(
        @babel/core
        @babel/plugin-transform-runtime
        @babel/preset-env
        @babel/runtime
        babel-loader
        compression-webpack-plugin
        shakapacker
        terser-webpack-plugin
        webpack
        webpack-assets-manifest
        webpack-cli
        webpack-dev-server
        webpack-merge
        @rails/actioncable
        @rails/activestorage
        @rails/ujs
        turbolinks
      )
      system! "npm uninstall #{webpacker_packages.join(" ")}"

      # Add the Browserslist configuration to the project
      add_decidim_browserslist_configuration
    end
  end

  namespace :upgrade do
    desc "Upgrades Decidim webpacker dependencies in Rails instance application"
    task webpacker: :environment do
      raise "Decidim gem is not installed" if decidim_path.nil?

      remove_file_from_application "bin/yarn"

      unless File.exist?(rails_app_path.join("config/esbuild.config.js"))
        copy_file_to_application "decidim-core/lib/decidim/webpacker/esbuild.config.js",
                                 "config/esbuild.config.js"
      end
      unless File.exist?(rails_app_path.join("tsconfig.json"))
        copy_file_to_application "decidim-core/lib/decidim/webpacker/tsconfig.json",
                                 "tsconfig.json"
      end

      # Remove the Webpacker config and deploy shakapacker
      migrate_shakapacker

      # Update JS dependencies
      install_decidim_npm
    end
  end

  def migrate_shakapacker
    remove_file_from_application "config/webpacker.yml"
    remove_file_from_application "bin/webpack"
    remove_file_from_application "bin/webpack-dev-server"

    unless File.exist?(rails_app_path.join("config/shakapacker.yml"))
      copy_file_to_application "decidim-core/lib/decidim/webpacker/shakapacker.yml", "config/shakapacker.yml"
      remove_folder_from_application "config/webpack"
    end

    copy_folder_to_application "decidim-core/lib/decidim/webpacker/webpack", "config"

    system!("bin/rails shakapacker:binstubs") unless File.exist?(rails_app_path.join("bin/shakapacker"))

    # Modify the webpack binstubs
    add_binstub_load_path "bin/shakapacker"
    add_binstub_load_path "bin/shakapacker-dev-server"
  end

  def install_decidim_npm
    decidim_npm_packages.each do |type, packages|
      system! "npm i --save-#{type} #{packages.join(" ")}"
    end
  end

  def add_decidim_browserslist_configuration
    package = JSON.parse(File.read(rails_app_path.join("package.json")))
    return if package["browserslist"].is_a?(Array) && package["browserslist"].include?("extends @decidim/browserslist-config")

    package["browserslist"] = ["extends @decidim/browserslist-config"]
    File.write(rails_app_path.join("package.json"), JSON.pretty_generate(package))
  end

  def decidim_npm_packages
    gem_path = unreleased_gem_path

    if gem_path
      package_spec = "./packages/%s"

      # The packages folder needs to be copied to the application folder
      # because the linked dependencies are not installed when packages
      # are installed using file references outside the application root
      # where the `package.json` is located at. For more information, see:
      # https://github.com/npm/cli/issues/2339
      FileUtils.rm_rf(rails_app_path.join("packages"))
      FileUtils.cp_r(gem_path.join("packages"), rails_app_path)
    else
      package_spec = "@decidim/%s@~#{Decidim::GemManager.semver_friendly_version(decidim_gemspec.version.to_s)}"
    end

    local_npm_dependencies.transform_values { |names| names.map { |name| format(package_spec, name) } }
  end

  def unreleased_gem_path
    if decidim_gemspec.source.is_a?(Bundler::Source::Rubygems)
      return if released_version?

      gem_path = Pathname(decidim_gemspec.full_gem_path)
    else
      gem_path = decidim_gemspec.source.path
      gem_path = Pathname(ENV.fetch("BUNDLE_GEMFILE", nil)).dirname.join(gem_path) if gem_path.relative?
    end

    gem_path
  end

  def local_npm_dependencies
    @local_npm_dependencies ||= begin
      package_json = JSON.parse(File.read(decidim_path.join("package.json")))

      {
        prod: local_npm_dependencies_list(package_json["dependencies"]),
        dev: local_npm_dependencies_list(package_json["devDependencies"])
      }.freeze
    end
  end

  def local_npm_dependencies_list(deps)
    return [] unless deps

    deps.values
        .select { |ref| ref.starts_with?("file:packages/") }
        .map { |ref| ref.delete_prefix("file:packages/") }
  end

  def decidim_path
    @decidim_path ||= Pathname.new(decidim_gemspec.full_gem_path) if Gem.loaded_specs.has_key?("decidim")
  end

  def decidim_gemspec
    @decidim_gemspec ||= Gem.loaded_specs["decidim"]
  end

  def released_version?
    decidim_gemspec.version.segments.last != "dev"
  end

  def rails_app_path
    @rails_app_path ||= Rails.root
  end

  def copy_file_to_application(origin_path, destination_path = origin_path)
    FileUtils.cp(decidim_path.join(origin_path), rails_app_path.join(destination_path))
  end

  def copy_folder_to_application(origin_path, destination_path = origin_path)
    FileUtils.cp_r(decidim_path.join(origin_path), rails_app_path.join(destination_path))
  end

  def remove_file_from_application(path)
    FileUtils.rm(path, force: true)
  end

  def remove_folder_from_application(path)
    FileUtils.rm_rf(path)
  end

  def add_binstub_load_path(binstub_path)
    file = rails_app_path.join(binstub_path)
    lines = File.readlines(file)

    # Skip if the load path is already added
    return if lines.grep(
      %r{^\$LOAD_PATH.unshift "#\{Gem.loaded_specs\["decidim-core"\].full_gem_path\}/lib/gem_overrides"$}
    ).size.positive?

    contents = ""
    lines.each do |line|
      contents += line
      next unless line =~ %r{^require "bundler/setup"$}

      contents += "\n"
      contents += "# Add the Decidim override load path to override webpacker functionality\n"
      contents += "$LOAD_PATH.unshift \"\#{Gem.loaded_specs[\"decidim-core\"].full_gem_path}/lib/gem_overrides\"\n"
    end

    File.write(file, contents)
  end

  def system!(command)
    system("cd #{rails_app_path} && #{command}") || abort("\n== Command #{command} failed ==")
  end
end

# Override the Webpacker instance for the rake tasks to correctly assign the
# configuration file path. This is needed e.g. when `rails assets:precompile` is
# being run. Otherwise webpacker might not recognize if the assets need to be
# compiled again (i.e. if the asset hash has been changed).
if (config_path = Decidim::Webpacker.configuration.configuration_file)
  Shakapacker.instance = Shakapacker::Instance.new(
    config_path: Pathname.new(config_path)
  )
end

# Add gem overrides path to the beginning in order to override rake tasks
# Needed because of a bug in Rails 6.0 (see the overridden task for details)
$LOAD_PATH.unshift "#{Gem.loaded_specs["decidim-core"].full_gem_path}/lib/gem_overrides"