#
# Author:: Prajakta Purohit (<prajakta@chef.io>)
# Author:: Lamont Granquist (<lamont@chef.io>)
#
# Copyright:: Copyright 2011-2016, Chef Software Inc.
#
# 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/config"
require "chef/log"
require "chef/resource/file"
require "chef/mixin/checksum"
require "chef/provider"
require "etc"
require "fileutils"
require "chef/scan_access_control"
require "chef/win32/registry"

class Chef

  class Provider
    class RegistryKey < Chef::Provider
      provides :registry_key

      include Chef::Mixin::Checksum

      def whyrun_supported?
        true
      end

      def running_on_windows!
        unless Chef::Platform.windows?
          raise Chef::Exceptions::Win32NotWindows, "Attempt to manipulate the windows registry on a non-windows node"
        end
      end

      def load_current_resource
        running_on_windows!
        @current_resource ||= Chef::Resource::RegistryKey.new(@new_resource.key, run_context)
        @current_resource.key(@new_resource.key)
        @current_resource.architecture(@new_resource.architecture)
        @current_resource.recursive(@new_resource.recursive)
        if registry.key_exists?(@new_resource.key)
          @current_resource.values(registry.get_values(@new_resource.key))
        end
        values_to_hash(@current_resource.unscrubbed_values)
        @current_resource
      end

      def registry
        @registry ||= Chef::Win32::Registry.new(@run_context, @new_resource.architecture)
      end

      def values_to_hash(values)
        if values
          @name_hash = Hash[values.map { |val| [val[:name].downcase, val] }]
        else
          @name_hash = {}
        end
      end

      def define_resource_requirements
        requirements.assert(:create, :create_if_missing, :delete, :delete_key) do |a|
          a.assertion { registry.hive_exists?(@new_resource.key) }
          a.failure_message(Chef::Exceptions::Win32RegHiveMissing, "Hive #{@new_resource.key.split("\\").shift} does not exist")
        end
        requirements.assert(:create) do |a|
          a.assertion { registry.key_exists?(@new_resource.key) }
          a.whyrun("Key #{@new_resource.key} does not exist. Unless it would have been created before, attempt to modify its values would fail.")
        end
        requirements.assert(:create, :create_if_missing) do |a|
          #If keys missing in the path and recursive == false
          a.assertion { !registry.keys_missing?(@current_resource.key) || @new_resource.recursive }
          a.failure_message(Chef::Exceptions::Win32RegNoRecursive, "Intermediate keys missing but recursive is set to false")
          a.whyrun("Intermediate keys in #{@new_resource.key} do not exist. Unless they would have been created earlier, attempt to modify them would fail.")
        end
        requirements.assert(:delete_key) do |a|
          #If key to be deleted has subkeys but recurssive == false
          a.assertion { !registry.key_exists?(@new_resource.key) || !registry.has_subkeys?(@new_resource.key) || @new_resource.recursive }
          a.failure_message(Chef::Exceptions::Win32RegNoRecursive, "#{@new_resource.key} has subkeys but recursive is set to false.")
          a.whyrun("#{@current_resource.key} has subkeys, but recursive is set to false. attempt to delete would fails unless subkeys were deleted prior to this action.")
        end
      end

      def action_create
        unless registry.key_exists?(@current_resource.key)
          converge_by("create key #{@new_resource.key}") do
            registry.create_key(@new_resource.key, @new_resource.recursive)
          end
        end
        @new_resource.unscrubbed_values.each do |value|
          if @name_hash.has_key?(value[:name].downcase)
            current_value = @name_hash[value[:name].downcase]
            unless current_value[:type] == value[:type] && current_value[:data] == value[:data]
              converge_by("set value #{value}") do
                registry.set_value(@new_resource.key, value)
              end
            end
          else
            converge_by("set value #{value}") do
              registry.set_value(@new_resource.key, value)
            end
          end
        end
      end

      def action_create_if_missing
        unless registry.key_exists?(@new_resource.key)
          converge_by("create key #{@new_resource.key}") do
            registry.create_key(@new_resource.key, @new_resource.recursive)
          end
        end
        @new_resource.unscrubbed_values.each do |value|
          unless @name_hash.has_key?(value[:name].downcase)
            converge_by("create value #{value}") do
              registry.set_value(@new_resource.key, value)
            end
          end
        end
      end

      def action_delete
        if registry.key_exists?(@new_resource.key)
          @new_resource.unscrubbed_values.each do |value|
            if @name_hash.has_key?(value[:name].downcase)
              converge_by("delete value #{value}") do
                registry.delete_value(@new_resource.key, value)
              end
            end
          end
        end
      end

      def action_delete_key
        if registry.key_exists?(@new_resource.key)
          converge_by("delete key #{@new_resource.key}") do
            registry.delete_key(@new_resource.key, @new_resource.recursive)
          end
        end
      end

    end
  end
end
