#
# Author:: Bryan McLellan (btm@loftninjas.org)
# Copyright:: Copyright 2009-2016, Bryan McLellan
# 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/resource/service"
require "chef/provider/service/init"

class Chef
  class Provider
    class Service
      class Freebsd < Chef::Provider::Service::Init

        attr_reader :enabled_state_found

        provides :service, os: %w{freebsd netbsd}

        include Chef::Mixin::ShellOut

        def initialize(new_resource, run_context)
          super
          @enabled_state_found = false
          @init_command = nil
          if ::File.exist?("/etc/rc.d/#{new_resource.service_name}")
            @init_command = "/etc/rc.d/#{new_resource.service_name}"
          elsif ::File.exist?("/usr/local/etc/rc.d/#{new_resource.service_name}")
            @init_command = "/usr/local/etc/rc.d/#{new_resource.service_name}"
          end
        end

        def load_current_resource
          @current_resource = Chef::Resource::Service.new(new_resource.name)
          current_resource.service_name(new_resource.service_name)

          return current_resource unless init_command

          logger.trace("#{current_resource} found at #{init_command}")

          @status_load_success = true
          determine_current_status! # see Chef::Provider::Service::Simple

          determine_enabled_status!
          current_resource
        end

        def define_resource_requirements
          shared_resource_requirements

          requirements.assert(:start, :enable, :reload, :restart) do |a|
            a.assertion { init_command }
            a.failure_message Chef::Exceptions::Service, "#{new_resource}: unable to locate the rc.d script"
            a.whyrun("Assuming rc.d script will be installed by a previous action.")
          end

          requirements.assert(:all_actions) do |a|
            a.assertion { enabled_state_found }
            # for consistentcy with original behavior, this will not fail in non-whyrun mode;
            # rather it will silently set enabled state=>false
            a.whyrun "Unable to determine enabled/disabled state, assuming this will be correct for an actual run.  Assuming disabled."
          end

          requirements.assert(:start, :enable, :reload, :restart) do |a|
            a.assertion { !service_enable_variable_name.nil? }
            a.failure_message Chef::Exceptions::Service, "Could not find the service name in #{init_command} and rcvar"
            # No recovery in whyrun mode - the init file is present but not correct.
          end
        end

        def start_service
          if new_resource.start_command
            super
          else
            shell_out!("#{init_command} faststart", default_env: false)
          end
        end

        def stop_service
          if new_resource.stop_command
            super
          else
            shell_out!("#{init_command} faststop", default_env: false)
          end
        end

        def restart_service
          if new_resource.restart_command
            super
          elsif supports[:restart]
            shell_out!("#{init_command} fastrestart", default_env: false)
          else
            stop_service
            sleep 1
            start_service
          end
        end

        def enable_service
          set_service_enable("YES") unless current_resource.enabled
        end

        def disable_service
          set_service_enable("NO") if current_resource.enabled
        end

        private

        def read_rc_conf
          ::File.open("/etc/rc.conf", "r") { |file| file.readlines }
        end

        def write_rc_conf(lines)
          ::File.open("/etc/rc.conf", "w") do |file|
            lines.each { |line| file.puts(line) }
          end
        end

        # The variable name used in /etc/rc.conf for enabling this service
        def service_enable_variable_name
          @service_enable_variable_name ||=
            begin
              # Look for name="foo" in the shell script @init_command. Use this for determining the variable name in /etc/rc.conf
              # corresponding to this service
              # For example: to enable the service mysql-server with the init command /usr/local/etc/rc.d/mysql-server, you need
              # to set mysql_enable="YES" in /etc/rc.conf$
              if init_command
                ::File.open(init_command) do |rcscript|
                  rcscript.each_line do |line|
                    if line =~ /^name="?(\w+)"?/
                      return $1 + "_enable"
                    end
                  end
                end
                # some scripts support multiple instances through symlinks such as openvpn.
                # We should get the service name from rcvar.
                logger.trace("name=\"service\" not found at #{init_command}. falling back to rcvar")
                shell_out!("#{init_command} rcvar").stdout[/(\w+_enable)=/, 1]
              else
                # for why-run mode when the rcd_script is not there yet
                new_resource.service_name
              end
            end
        end

        def determine_enabled_status!
          var_name = service_enable_variable_name
          if ::File.exist?("/etc/rc.conf") && var_name
            read_rc_conf.each do |line|
              case line
              when /^#{Regexp.escape(var_name)}="(\w+)"/
                enabled_state_found!
                if $1 =~ /^yes$/i
                  current_resource.enabled true
                elsif $1 =~ /^(no|none)$/i
                  current_resource.enabled false
                end
              end
            end
          end

          if current_resource.enabled.nil?
            logger.trace("#{new_resource.name} enable/disable state unknown")
            current_resource.enabled false
          end
        end

        def set_service_enable(value)
          lines = read_rc_conf
          # Remove line that set the old value
          lines.delete_if { |line| line =~ /^\#?\s*#{Regexp.escape(service_enable_variable_name)}=/ }
          # And append the line that sets the new value at the end
          lines << "#{service_enable_variable_name}=\"#{value}\""
          write_rc_conf(lines)
        end

        def enabled_state_found!
          @enabled_state_found = true
        end
      end
    end
  end
end