# Copied from https://github.com/rails/rails/blob/38275763257221e381cd4e37958ce1413fd0433c/railties/lib/rails/generators/actions.rb
module Rails
  module Actions
    # Adds an entry into +Gemfile+ for the supplied gem.
    #
    #   gem "rspec", group: :test
    #   gem "technoweenie-restful-authentication", lib: "restful-authentication", source: "http://gems.github.com/"
    #   gem "rails", "3.0", git: "https://github.com/rails/rails"
    #   gem "RedCloth", ">= 4.1.0", "< 4.2.0"
    #   gem "rspec", comment: "Put this comment above the gem declaration"
    def gem(*args, **options)
      name, *versions = args

      # Set the message to be shown in logs. Uses the git repo if one is given,
      # otherwise use name (version).
      parts, message = [quote(name)], name.dup

      # Output a comment above the gem declaration.
      comment = options.delete(:comment)

      if versions = versions.any? ? versions : options.delete(:version)
        _versions = Array(versions)
        _versions.each do |version|
          parts << quote(version)
        end
        message << " (#{_versions.join(", ")})"
      end
      message = options[:git] if options[:git]

      log :gemfile, message

      parts << quote(options) unless options.empty?

      in_root do
        str = []
        if comment
          comment.each_line do |comment_line|
            str << indentation
            str << "# #{comment_line}"
          end
          str << "\n"
        end
        str << indentation
        str << "gem #{parts.join(", ")}"
        append_file_with_newline "Gemfile", str.join, verbose: false
      end
    end

    # Wraps gem entries inside a group.
    #
    #   gem_group :development, :test do
    #     gem "rspec-rails"
    #   end
    def gem_group(*names, **options, &block)
      str = names.map(&:inspect)
      str << quote(options) unless options.empty?
      str = str.join(", ")
      log :gemfile, "group #{str}"

      in_root do
        append_file_with_newline "Gemfile", "\ngroup #{str} do", force: true
        with_indentation(&block)
        append_file_with_newline "Gemfile", "end", force: true
      end
    end

    def github(repo, options = {}, &block)
      str = [quote(repo)]
      str << quote(options) unless options.empty?
      str = str.join(", ")
      log :github, "github #{str}"

      in_root do
        if @indentation.zero?
          append_file_with_newline "Gemfile", "\ngithub #{str} do", force: true
        else
          append_file_with_newline "Gemfile", "#{indentation}github #{str} do", force: true
        end
        with_indentation(&block)
        append_file_with_newline "Gemfile", "#{indentation}end", force: true
      end
    end

    # Add the given source to +Gemfile+
    #
    # If block is given, gem entries in block are wrapped into the source group.
    #
    #   add_source "http://gems.github.com/"
    #
    #   add_source "http://gems.github.com/" do
    #     gem "rspec-rails"
    #   end
    def add_source(source, options = {}, &block)
      log :source, source

      in_root do
        if block
          append_file_with_newline "Gemfile", "\nsource #{quote(source)} do", force: true
          with_indentation(&block)
          append_file_with_newline "Gemfile", "end", force: true
        else
          prepend_file "Gemfile", "source #{quote(source)}\n", verbose: false
        end
      end
    end

    # Adds a line inside the Application class for <tt>config/application.rb</tt>.
    #
    # If options <tt>:env</tt> is specified, the line is appended to the corresponding
    # file in <tt>config/environments</tt>.
    #
    #   environment do
    #     "config.asset_host = 'cdn.provider.com'"
    #   end
    #
    #   environment(nil, env: "development") do
    #     "config.asset_host = 'localhost:3000'"
    #   end
    def environment(data = nil, options = {})
      sentinel = "class Application < Rails::Application\n"
      env_file_sentinel = "Rails.application.configure do\n"
      data ||= yield if block_given?

      in_root do
        if options[:env].nil?
          inject_into_file "config/application.rb", optimize_indentation(data, 4), after: sentinel, verbose: false
        else
          Array(options[:env]).each do |env|
            inject_into_file "config/environments/#{env}.rb", optimize_indentation(data, 2), after: env_file_sentinel, verbose: false
          end
        end
      end
    end
    alias_method :application, :environment

    # Run a command in git.
    #
    #   git :init
    #   git add: "this.file that.rb"
    #   git add: "onefile.rb", rm: "badfile.cxx"
    def git(commands = {})
      if commands.is_a?(Symbol)
        run "git #{commands}"
      else
        commands.each do |cmd, options|
          run "git #{cmd} #{options}"
        end
      end
    end

    # Create a new file in the <tt>vendor/</tt> directory. Code can be specified
    # in a block or a data string can be given.
    #
    #   vendor("sekrit.rb") do
    #     sekrit_salt = "#{Time.now}--#{3.years.ago}--#{rand}--"
    #     "salt = '#{sekrit_salt}'"
    #   end
    #
    #   vendor("foreign.rb", "# Foreign code is fun")
    def vendor(filename, data = nil)
      log :vendor, filename
      data ||= yield if block_given?
      create_file("vendor/#{filename}", optimize_indentation(data), verbose: false)
    end

    # Create a new file in the <tt>lib/</tt> directory. Code can be specified
    # in a block or a data string can be given.
    #
    #   lib("crypto.rb") do
    #     "crypted_special_value = '#{rand}--#{Time.now}--#{rand(1337)}--'"
    #   end
    #
    #   lib("foreign.rb", "# Foreign code is fun")
    def lib(filename, data = nil)
      log :lib, filename
      data ||= yield if block_given?
      create_file("lib/#{filename}", optimize_indentation(data), verbose: false)
    end

    # Create a new +Rakefile+ with the provided code (either in a block or a string).
    #
    #   rakefile("bootstrap.rake") do
    #     project = ask("What is the UNIX name of your project?")
    #
    #     <<-TASK
    #       namespace :#{project} do
    #         task :bootstrap do
    #           puts "I like boots!"
    #         end
    #       end
    #     TASK
    #   end
    #
    #   rakefile('seed.rake', 'puts "Planting seeds"')
    def rakefile(filename, data = nil)
      log :rakefile, filename
      data ||= yield if block_given?
      create_file("lib/tasks/#{filename}", optimize_indentation(data), verbose: false)
    end

    # Create a new initializer with the provided code (either in a block or a string).
    #
    #   initializer("globals.rb") do
    #     data = ""
    #
    #     ['MY_WORK', 'ADMINS', 'BEST_COMPANY_EVAR'].each do |const|
    #       data << "#{const} = :entp\n"
    #     end
    #
    #     data
    #   end
    #
    #   initializer("api.rb", "API_KEY = '123456'")
    def initializer(filename, data = nil)
      log :initializer, filename
      data ||= yield if block_given?
      create_file("config/initializers/#{filename}", optimize_indentation(data), verbose: false)
    end

    # Generate something using a generator from Rails or a plugin.
    # The second parameter is the argument string that is passed to
    # the generator or an Array that is joined.
    #
    #   generate(:authenticated, "user session")
    def generate(what, *args)
      log :generate, what

      options = args.extract_options!
      options[:abort_on_failure] = !options[:inline]

      rails_command "generate #{what} #{args.join(" ")}", options
    end

    # Runs the supplied rake task (invoked with 'rake ...')
    #
    #   rake("db:migrate")
    #   rake("db:migrate", env: "production")
    #   rake("gems:install", sudo: true)
    #   rake("gems:install", capture: true)
    def rake(command, options = {})
      execute_command :rake, command, options
    end

    # Runs the supplied rake task (invoked with 'rails ...')
    #
    #   rails_command("db:migrate")
    #   rails_command("db:migrate", env: "production")
    #   rails_command("gems:install", sudo: true)
    #   rails_command("gems:install", capture: true)
    def rails_command(command, options = {})
      if options[:inline]
        log :rails, command
        command, *args = Shellwords.split(command)
        in_root do
          silence_warnings do
            ::Rails::Command.invoke(command, args, **options)
          end
        end
      else
        execute_command :rails, command, options
      end
    end

    # Make an entry in Rails routing file <tt>config/routes.rb</tt>
    #
    #   route "root 'welcome#index'"
    #   route "root 'admin#index'", namespace: :admin
    def route(routing_code, namespace: nil)
      namespace = Array(namespace)
      namespace_pattern = route_namespace_pattern(namespace)
      routing_code = namespace.reverse.reduce(routing_code) do |code, name|
        "namespace :#{name} do\n#{rebase_indentation(code, 2)}end"
      end

      log :route, routing_code

      in_root do
        if namespace_match = match_file("config/routes.rb", namespace_pattern)
          base_indent, *, existing_block_indent = namespace_match.captures.compact.map(&:length)
          existing_line_pattern = /^ {,#{existing_block_indent}}\S.+\n?/
          routing_code = rebase_indentation(routing_code, base_indent + 2).gsub(existing_line_pattern, "")
          namespace_pattern = /#{Regexp.escape namespace_match.to_s}/
        end

        inject_into_file "config/routes.rb", routing_code, after: namespace_pattern, verbose: false, force: false

        if behavior == :revoke && namespace.any? && namespace_match
          empty_block_pattern = /(#{namespace_pattern})((?:\s*end\n){1,#{namespace.size}})/
          gsub_file "config/routes.rb", empty_block_pattern, verbose: false, force: true do |matched|
            beginning, ending = empty_block_pattern.match(matched).captures
            ending.sub!(/\A\s*end\n/, "") while !ending.empty? && beginning.sub!(/^ *namespace .+ do\n\s*\z/, "")
            beginning + ending
          end
        end
      end
    end

    # Reads the given file at the source root and prints it in the console.
    #
    #   readme "README"
    def readme(path)
      log File.read(find_in_source_paths(path))
    end

    private

    # Define log for backwards compatibility. If just one argument is sent,
    # invoke say, otherwise invoke say_status. Differently from say and
    # similarly to say_status, this method respects the quiet? option given.
    def log(*args) # :doc:
      if args.size == 1
        say args.first.to_s unless options.quiet?
      else
        args << ((behavior == :invoke) ? :green : :red)
        say_status(*args)
      end
    end

    # Runs the supplied command using either "rake ..." or "rails ..."
    # based on the executor parameter provided.
    def execute_command(executor, command, options = {}) # :doc:
      log executor, command
      sudo = (options[:sudo] && !Gem.win_platform?) ? "sudo " : ""
      config = {
        env: {"RAILS_ENV" => (options[:env] || ENV["RAILS_ENV"] || "development")},
        verbose: false,
        capture: options[:capture],
        abort_on_failure: options[:abort_on_failure]
      }

      in_root { run("#{sudo}#{Shellwords.escape Gem.ruby} bin/#{executor} #{command}", config) }
    end

    # Always returns value in double quotes.
    def quote(value) # :doc:
      if value.respond_to? :each_pair
        return value.map do |k, v|
          "#{k}: #{quote(v)}"
        end.join(", ")
      end
      return value.inspect unless value.is_a? String

      "\"#{value.tr("'", '"')}\""
    end

    # Returns optimized string with indentation
    def optimize_indentation(value, amount = 0) # :doc:
      return "#{value}\n" unless value.is_a?(String)
      "#{value.strip_heredoc.indent(amount).chomp}\n"
    end
    alias_method :rebase_indentation, :optimize_indentation

    # Indent the +Gemfile+ to the depth of @indentation
    def indentation # :doc:
      "  " * @indentation
    end

    # Manage +Gemfile+ indentation for a DSL action block
    def with_indentation(&block) # :doc:
      @indentation += 1
      instance_eval(&block)
    ensure
      @indentation -= 1
    end

    # Append string to a file with a newline if necessary
    def append_file_with_newline(path, str, options = {})
      gsub_file path, /\n?\z/, options do |match|
        match.end_with?("\n") ? "" : "\n#{str}\n"
      end
    end

    def match_file(path, pattern)
      File.read(path).match(pattern) if File.exist?(path)
    end

    def route_namespace_pattern(namespace)
      namespace.each_with_index.reverse_each.reduce(nil) do |pattern, (name, i)|
        cummulative_margin = "\\#{i + 1}[ ]{2}"
        blank_or_indented_line = "^[ ]*\n|^#{cummulative_margin}.*\n"
        "(?:(?:#{blank_or_indented_line})*?^(#{cummulative_margin})namespace :#{name} do\n#{pattern})?"
      end.then do |pattern|
        /^( *).+\.routes\.draw do *\n#{pattern}/
      end
    end
  end
end
