#
# Author:: Adam Jacob (<adam@chef.io>)
# Copyright:: Copyright 2009-2016, Chef Software Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

require "chef/knife"

class Chef
  class Knife
    class CookbookDelete < Knife

      attr_accessor :cookbook_name, :version

      deps do
        require "chef/cookbook_version"
      end

      option :all, short: "-a", long: "--all", boolean: true, description: "Delete all versions of the cookbook."

      option :purge, short: "-p", long: "--purge", boolean: true, description: "Permanently remove files from backing data store."

      banner "knife cookbook delete COOKBOOK VERSION (options)"

      def run
        confirm("Files that are common to multiple cookbooks are shared, so purging the files may disable other cookbooks. Are you sure you want to purge files instead of just deleting the cookbook") if config[:purge]
        @cookbook_name, @version = name_args
        if @cookbook_name && @version
          delete_explicit_version
        elsif @cookbook_name && config[:all]
          delete_all_versions
        elsif @cookbook_name && @version.nil?
          delete_without_explicit_version
        elsif @cookbook_name.nil?
          show_usage
          ui.fatal("You must provide the name of the cookbook to delete.")
          exit(1)
        end
      end

      def delete_explicit_version
        delete_object(Chef::CookbookVersion, "#{@cookbook_name} version #{@version}", "cookbook") do
          delete_request("cookbooks/#{@cookbook_name}/#{@version}")
        end
      end

      def delete_all_versions
        confirm("Do you really want to delete all versions of #{@cookbook_name}")
        delete_all_without_confirmation
      end

      def delete_all_without_confirmation
        # look up the available versions again just in case the user
        # got to the list of versions to delete and selected 'all'
        # and also a specific version
        @available_versions = nil
        Array(available_versions).each do |version|
          delete_version_without_confirmation(version)
        end
      end

      def delete_without_explicit_version
        if available_versions.nil?
          # we already logged an error or 2 about it, so just bail
          exit(1)
        elsif available_versions.size == 1
          @version = available_versions.first
          delete_explicit_version
        else
          versions_to_delete = ask_which_versions_to_delete
          delete_versions_without_confirmation(versions_to_delete)
        end
      end

      def available_versions
        @available_versions ||= rest.get("cookbooks/#{@cookbook_name}").map do |name, url_and_version|
          url_and_version["versions"].map { |url_by_version| url_by_version["version"] }
        end.flatten
      rescue Net::HTTPServerException => e
        if e.to_s =~ /^404/
          ui.error("Cannot find a cookbook named #{@cookbook_name} to delete.")
          nil
        else
          raise
        end
      end

      def ask_which_versions_to_delete
        question = "Which version(s) do you want to delete?\n"
        valid_responses = {}
        available_versions.each_with_index do |version, index|
          valid_responses[(index + 1).to_s] = version
          question << "#{index + 1}. #{@cookbook_name} #{version}\n"
        end
        valid_responses[(available_versions.size + 1).to_s] = :all
        question << "#{available_versions.size + 1}. All versions\n\n"
        responses = ask_question(question).split(",").map { |response| response.strip }

        if responses.empty?
          ui.error("No versions specified, exiting")
          exit(1)
        end
        versions = responses.map do |response|
          if version = valid_responses[response]
            version
          else
            ui.error("#{response} is not a valid choice, skipping it")
          end
        end
        versions.compact
      end

      def delete_version_without_confirmation(version)
        object = delete_request("cookbooks/#{@cookbook_name}/#{version}")
        output(format_for_display(object)) if config[:print_after]
        ui.info("Deleted cookbook[#{@cookbook_name}][#{version}]")
      end

      def delete_versions_without_confirmation(versions)
        versions.each do |version|
          if version == :all
            delete_all_without_confirmation
            break
          else
            delete_version_without_confirmation(version)
          end
        end
      end

      private

      def delete_request(path)
        path += "?purge=true" if config[:purge]
        rest.delete(path)
      end

    end
  end
end