#
# Author:: Adam Jacob (<adam@chef.io>)
# Author:: Christopher Brown (<cb@chef.io>)
# Copyright:: Copyright 2009-2018, 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 "forwardable"
require "chef/version"
require "mixlib/cli"
require "chef/workstation_config_loader"
require "chef/mixin/convert_to_class_name"
require "chef/mixin/path_sanity"
require "chef/knife/core/subcommand_loader"
require "chef/knife/core/ui"
require "chef/local_mode"
require "chef/server_api"
require "chef/http/authenticator"
require "chef/http/http_request"
require "chef/http"
require "pp"

class Chef
  class Knife

    Chef::HTTP::HTTPRequest.user_agent = "Chef Knife#{Chef::HTTP::HTTPRequest::UA_COMMON}"

    include Mixlib::CLI
    include Chef::Mixin::PathSanity
    extend Chef::Mixin::ConvertToClassName
    extend Forwardable

    # @note Backwards Compat:
    #   Ideally, we should not vomit all of these methods into this base class;
    #   instead, they should be accessed by hitting the ui object directly.
    def_delegator :@ui, :stdout
    def_delegator :@ui, :stderr
    def_delegator :@ui, :stdin
    def_delegator :@ui, :msg
    def_delegator :@ui, :ask_question
    def_delegator :@ui, :pretty_print
    def_delegator :@ui, :output
    def_delegator :@ui, :format_list_for_display
    def_delegator :@ui, :format_for_display
    def_delegator :@ui, :format_cookbook_list_for_display
    def_delegator :@ui, :edit_data
    def_delegator :@ui, :edit_hash
    def_delegator :@ui, :edit_object
    def_delegator :@ui, :confirm

    attr_accessor :name_args
    attr_accessor :ui

    # Configure mixlib-cli to always separate defaults from user-supplied CLI options
    def self.use_separate_defaults?
      true
    end

    def self.ui
      @ui ||= Chef::Knife::UI.new(STDOUT, STDERR, STDIN, {})
    end

    def self.msg(msg = "")
      ui.msg(msg)
    end

    def self.reset_config_loader!
      @@chef_config_dir = nil
      @config_loader = nil
    end

    def self.reset_subcommands!
      @@subcommands = {}
      @subcommands_by_category = nil
    end

    def self.inherited(subclass)
      unless subclass.unnamed?
        subcommands[subclass.snake_case_name] = subclass
        subcommand_files[subclass.snake_case_name] +=
          if subclass.superclass.to_s == "Chef::ChefFS::Knife"
            # ChefFS-based commands have a superclass that defines an
            # inhereited method which calls super. This means that the
            # top of the call stack is not the class definition for
            # our subcommand.  Try the second entry in the call stack.
            [path_from_caller(caller[1])]
          else
            [path_from_caller(caller[0])]
          end
      end
    end

    # Explicitly set the category for the current command to +new_category+
    # The category is normally determined from the first word of the command
    # name, but some commands make more sense using two or more words
    # @param new_category [String] value to set the category to (see examples)
    #
    # @example Data bag commands would be in the 'data' category by default. To
    #  put them in the 'data bag' category:
    #  category('data bag')
    def self.category(new_category)
      @category = new_category
    end

    def self.subcommand_category
      @category || snake_case_name.split("_").first unless unnamed?
    end

    def self.snake_case_name
      convert_to_snake_case(name.split("::").last) unless unnamed?
    end

    def self.common_name
      snake_case_name.split("_").join(" ")
    end

    # Does this class have a name? (Classes created via Class.new don't)
    def self.unnamed?
      name.nil? || name.empty?
    end

    def self.subcommand_loader
      @subcommand_loader ||= Chef::Knife::SubcommandLoader.for_config(chef_config_dir)
    end

    def self.load_commands
      @commands_loaded ||= subcommand_loader.load_commands
    end

    def self.guess_category(args)
      subcommand_loader.guess_category(args)
    end

    def self.subcommand_class_from(args)
      if args.size == 1 && args[0].strip.casecmp("rehash") == 0
        # To prevent issues with the rehash file not pointing to the correct plugins,
        # we always use the glob loader when regenerating the rehash file
        @subcommand_loader = Chef::Knife::SubcommandLoader.gem_glob_loader(chef_config_dir)
      end
      subcommand_loader.command_class_from(args) || subcommand_not_found!(args)
    end

    def self.subcommands
      @@subcommands ||= {}
    end

    def self.subcommand_files
      @@subcommand_files ||= Hash.new([])
    end

    def self.subcommands_by_category
      unless @subcommands_by_category
        @subcommands_by_category = Hash.new { |hash, key| hash[key] = [] }
        subcommands.each do |snake_cased, klass|
          @subcommands_by_category[klass.subcommand_category] << snake_cased
        end
      end
      @subcommands_by_category
    end

    # Shared with subclasses
    @@chef_config_dir = nil

    def self.config_loader
      @config_loader ||= WorkstationConfigLoader.new(nil, Chef::Log)
    end

    def self.load_config(explicit_config_file, profile)
      config_loader.explicit_config_file = explicit_config_file
      config_loader.profile = profile
      config_loader.load

      ui.warn("No knife configuration file found. See https://docs.chef.io/config_rb_knife.html for details.") if config_loader.no_config_found?

      config_loader
    rescue Exceptions::ConfigurationError => e
      ui.error(ui.color("CONFIGURATION ERROR:", :red) + e.message)
      exit 1
    end

    def self.chef_config_dir
      @@chef_config_dir ||= config_loader.chef_config_dir
    end

    # Run knife for the given +args+ (ARGV), adding +options+ to the list of
    # CLI options that the subcommand knows how to handle.
    #
    # @param args [Array] The arguments. Usually ARGV
    # @param options [Mixlib::CLI option parser hash] These +options+ are how
    #   subcommands know about global knife CLI options
    #
    def self.run(args, options = {})
      # Fallback debug logging. Normally the logger isn't configured until we
      # read the config, but this means any logging that happens before the
      # config file is read may be lost. If the KNIFE_DEBUG variable is set, we
      # setup the logger for debug logging to stderr immediately to catch info
      # from early in the setup process.
      if ENV["KNIFE_DEBUG"]
        Chef::Log.init($stderr)
        Chef::Log.level(:debug)
      end

      subcommand_class = subcommand_class_from(args)
      subcommand_class.options = options.merge!(subcommand_class.options)
      subcommand_class.load_deps
      instance = subcommand_class.new(args)
      instance.configure_chef
      instance.run_with_pretty_exceptions
    end

    def self.dependency_loaders
      @dependency_loaders ||= []
    end

    def self.deps(&block)
      dependency_loaders << block
    end

    def self.load_deps
      dependency_loaders.each do |dep_loader|
        dep_loader.call
      end
    end

    OFFICIAL_PLUGINS = %w{ec2 rackspace windows openstack azure google linode push vcenter lpar}.freeze

    class << self
      def list_commands(preferred_category = nil)
        category_desc = preferred_category ? preferred_category + " " : ""
        msg "Available #{category_desc}subcommands: (for details, knife SUB-COMMAND --help)\n\n"
        subcommand_loader.list_commands(preferred_category).sort.each do |category, commands|
          next if category =~ /deprecated/i
          msg "** #{category.upcase} COMMANDS **"
          commands.sort.each do |command|
            subcommand_loader.load_command(command)
            msg subcommands[command].banner if subcommands[command]
          end
          msg
        end
      end

      private

      # @api private
      def path_from_caller(caller_line)
        caller_line.split(/:\d+/).first
      end

      # Error out and print usage. probably because the arguments given by the
      # user could not be resolved to a subcommand.
      # @api private
      def subcommand_not_found!(args)
        ui.fatal("Cannot find subcommand for: '#{args.join(' ')}'")

        # Mention rehash when the subcommands cache(plugin_manifest.json) is used
        if subcommand_loader.is_a?(Chef::Knife::SubcommandLoader::HashedCommandLoader)
          ui.info("If this is a recently installed plugin, please run 'knife rehash' to update the subcommands cache.")
        end

        if category_commands = guess_category(args)
          list_commands(category_commands)
        elsif OFFICIAL_PLUGINS.include?(args[0]) # command was an uninstalled official chef knife plugin
          ui.info("Use `chef gem install knife-#{args[0]}` to install the plugin into ChefDK")
        else
          list_commands
        end

        exit 10
      end

      # @api private
      def reset_config_path!
        @@chef_config_dir = nil
      end

    end

    reset_config_path!

    # Create a new instance of the current class configured for the given
    # arguments and options
    def initialize(argv = [])
      super() # having to call super in initialize is the most annoying anti-pattern :(
      @ui = Chef::Knife::UI.new(STDOUT, STDERR, STDIN, config)

      command_name_words = self.class.snake_case_name.split("_")

      # Mixlib::CLI ignores the embedded name_args
      @name_args = parse_options(argv)
      @name_args.delete(command_name_words.join("-"))
      @name_args.reject! { |name_arg| command_name_words.delete(name_arg) }

      # knife node run_list add requires that we have extra logic to handle
      # the case that command name words could be joined by an underscore :/
      command_name_joined = command_name_words.join("_")
      @name_args.reject! { |name_arg| command_name_joined == name_arg }

      # Similar handling for hyphens.
      command_name_joined = command_name_words.join("-")
      @name_args.reject! { |name_arg| command_name_joined == name_arg }

      if config[:help]
        msg opt_parser
        exit 1
      end

      # copy Mixlib::CLI over so that it can be configured in knife.rb
      # config file
      Chef::Config[:verbosity] = config[:verbosity] if config[:verbosity]
    end

    def parse_options(args)
      super
    rescue OptionParser::InvalidOption => e
      puts "Error: " + e.to_s
      show_usage
      exit(1)
    end

    # keys from mixlib-cli options
    def cli_keys
      self.class.options.keys
    end

    # extracts the settings from the Chef::Config[:knife] sub-hash that correspond
    # to knife cli options -- in preparation for merging config values with cli values
    #
    # NOTE: due to weirdness in mixlib-config #has_key? is only true if the value has
    # been set by the user -- the Chef::Config defaults return #has_key?() of false and
    # this code DEPENDS on that functionality since applying the default values in
    # Chef::Config[:knife] would break the defaults in the cli that we would otherwise
    # overwrite.
    def config_file_settings
      cli_keys.each_with_object({}) do |key, memo|
        memo[key] = Chef::Config[:knife][key] if Chef::Config[:knife].key?(key)
      end
    end

    # config is merged in this order (inverse of precedence)
    #  default_config       - mixlib-cli defaults (accessor from the mixin)
    #  config_file_settings - Chef::Config[:knife] sub-hash
    #  config               - mixlib-cli settings (accessor from the mixin)
    def merge_configs
      # other code may have a handle to the config object, so use Hash#replace to deliberately
      # update-in-place.
      config.replace(
        default_config.merge(config_file_settings).merge(config)
      )
    end

    # Catch-all method that does any massaging needed for various config
    # components, such as expanding file paths and converting verbosity level
    # into log level.
    def apply_computed_config
      Chef::Config[:color] = config[:color]

      case Chef::Config[:verbosity]
      when 0, nil
        Chef::Config[:log_level] = :warn
      when 1
        Chef::Config[:log_level] = :info
      when 2
        Chef::Config[:log_level] = :debug
      else
        Chef::Config[:log_level] = :trace
      end

      Chef::Config[:log_level] = :trace if ENV["KNIFE_DEBUG"]

      Chef::Config[:node_name]         = config[:node_name]       if config[:node_name]
      Chef::Config[:client_key]        = config[:client_key]      if config[:client_key]
      Chef::Config[:chef_server_url]   = config[:chef_server_url] if config[:chef_server_url]
      Chef::Config[:environment]       = config[:environment]     if config[:environment]

      Chef::Config.local_mode = config[:local_mode] if config.key?(:local_mode)

      Chef::Config.listen = config[:listen] if config.key?(:listen)

      if Chef::Config.local_mode && !Chef::Config.key?(:cookbook_path) && !Chef::Config.key?(:chef_repo_path)
        Chef::Config.chef_repo_path = Chef::Config.find_chef_repo_path(Dir.pwd)
      end
      Chef::Config.chef_zero.host = config[:chef_zero_host] if config[:chef_zero_host]
      Chef::Config.chef_zero.port = config[:chef_zero_port] if config[:chef_zero_port]

      # Expand a relative path from the config directory. Config from command
      # line should already be expanded, and absolute paths will be unchanged.
      if Chef::Config[:client_key] && config[:config_file]
        Chef::Config[:client_key] = File.expand_path(Chef::Config[:client_key], File.dirname(config[:config_file]))
      end

      Mixlib::Log::Formatter.show_time = false
      Chef::Log.init(Chef::Config[:log_location])
      Chef::Log.level(Chef::Config[:log_level] || :error)
    end

    def configure_chef
      # knife needs to send logger output to STDERR by default
      Chef::Config[:log_location] = STDERR
      config_loader = self.class.load_config(config[:config_file], config[:profile])
      config[:config_file] = config_loader.config_location

      # For CLI options like `--config-option key=value`. These have to get
      # parsed and applied separately.
      extra_config_options = config.delete(:config_option)

      merge_configs
      apply_computed_config

      # This has to be after apply_computed_config so that Mixlib::Log is configured
      Chef::Log.info("Using configuration from #{config[:config_file]}") if config[:config_file]

      begin
        Chef::Config.apply_extra_config_options(extra_config_options)
      rescue ChefConfig::UnparsableConfigOption => e
        ui.error e.message
        show_usage
        exit(1)
      end

      Chef::Config.export_proxies
    end

    def show_usage
      stdout.puts("USAGE: " + opt_parser.to_s)
    end

    def run_with_pretty_exceptions(raise_exception = false)
      unless respond_to?(:run)
        ui.error "You need to add a #run method to your knife command before you can use it"
      end
      enforce_path_sanity
      maybe_setup_fips
      Chef::LocalMode.with_server_connectivity do
        run
      end
    rescue Exception => e
      raise if raise_exception || Chef::Config[:verbosity] == 2
      humanize_exception(e)
      exit 100
    end

    def humanize_exception(e)
      case e
      when SystemExit
        raise # make sure exit passes through.
      when Net::HTTPServerException, Net::HTTPFatalError
        humanize_http_exception(e)
      when OpenSSL::SSL::SSLError
        ui.error "Could not establish a secure connection to the server."
        ui.info "Use `knife ssl check` to troubleshoot your SSL configuration."
        ui.info "If your Chef Server uses a self-signed certificate, you can use"
        ui.info "`knife ssl fetch` to make knife trust the server's certificates."
        ui.info ""
        ui.info  "Original Exception: #{e.class.name}: #{e.message}"
      when Errno::ECONNREFUSED, Timeout::Error, Errno::ETIMEDOUT, SocketError
        ui.error "Network Error: #{e.message}"
        ui.info "Check your knife configuration and network settings"
      when NameError, NoMethodError
        ui.error "knife encountered an unexpected error"
        ui.info  "This may be a bug in the '#{self.class.common_name}' knife command or plugin"
        ui.info  "Please collect the output of this command with the `-VVV` option before filing a bug report."
        ui.info  "Exception: #{e.class.name}: #{e.message}"
      when Chef::Exceptions::PrivateKeyMissing
        ui.error "Your private key could not be loaded from #{api_key}"
        ui.info  "Check your configuration file and ensure that your private key is readable"
      when Chef::Exceptions::InvalidRedirect
        ui.error "Invalid Redirect: #{e.message}"
        ui.info  "Change your server location in knife.rb to the server's FQDN to avoid unwanted redirections."
      else
        ui.error "#{e.class.name}: #{e.message}"
      end
    end

    def humanize_http_exception(e)
      response = e.response
      case response
      when Net::HTTPUnauthorized
        ui.error "Failed to authenticate to #{server_url} as #{username} with key #{api_key}"
        ui.info "Response:  #{format_rest_error(response)}"
      when Net::HTTPForbidden
        ui.error "You authenticated successfully to #{server_url} as #{username} but you are not authorized for this action."
        proxy_env_vars = ENV.to_hash.keys.map(&:downcase) & %w{http_proxy https_proxy ftp_proxy socks_proxy no_proxy}
        unless proxy_env_vars.empty?
          ui.error "There are proxy servers configured, your Chef server may need to be added to NO_PROXY."
        end
        ui.info "Response:  #{format_rest_error(response)}"
      when Net::HTTPBadRequest
        ui.error "The data in your request was invalid"
        ui.info "Response: #{format_rest_error(response)}"
      when Net::HTTPNotFound
        ui.error "The object you are looking for could not be found"
        ui.info "Response: #{format_rest_error(response)}"
      when Net::HTTPInternalServerError
        ui.error "internal server error"
        ui.info "Response: #{format_rest_error(response)}"
      when Net::HTTPBadGateway
        ui.error "bad gateway"
        ui.info "Response: #{format_rest_error(response)}"
      when Net::HTTPServiceUnavailable
        ui.error "Service temporarily unavailable"
        ui.info "Response: #{format_rest_error(response)}"
      when Net::HTTPNotAcceptable
        version_header = Chef::JSONCompat.from_json(response["x-ops-server-api-version"])
        client_api_version = version_header["request_version"]
        min_server_version = version_header["min_version"]
        max_server_version = version_header["max_version"]
        ui.error "The version of Chef that Knife is using is not supported by the Chef server you sent this request to"
        ui.info "The request that Knife sent was using API version #{client_api_version}"
        ui.info "The Chef server you sent the request to supports a min API verson of #{min_server_version} and a max API version of #{max_server_version}"
        ui.info "Please either update your Chef client or server to be a compatible set"
      else
        ui.error response.message
        ui.info "Response: #{format_rest_error(response)}"
      end
    end

    def username
      Chef::Config[:node_name]
    end

    def api_key
      Chef::Config[:client_key]
    end

    # Parses JSON from the error response sent by Chef Server and returns the
    # error message
    #--
    # TODO: this code belongs in Chef::REST
    def format_rest_error(response)
      Array(Chef::JSONCompat.from_json(response.body)["error"]).join("; ")
    rescue Exception
      response.body
    end

    # FIXME: yard with @yield
    def create_object(object, pretty_name = nil, object_class: nil)
      output = if object_class
                 edit_data(object, object_class: object_class)
               else
                 edit_hash(object)
               end

      if Kernel.block_given?
        output = yield(output)
      else
        output.save
      end

      pretty_name ||= output

      msg("Created #{pretty_name}")

      output(output) if config[:print_after]
    end

    # FIXME: yard with @yield
    def delete_object(klass, name, delete_name = nil)
      confirm("Do you really want to delete #{name}")

      if Kernel.block_given?
        object = yield
      else
        object = klass.load(name)
        object.destroy
      end

      output(format_for_display(object)) if config[:print_after]

      obj_name = delete_name ? "#{delete_name}[#{name}]" : object
      msg("Deleted #{obj_name}")
    end

    # helper method for testing if a field exists
    # and returning the usage and proper error if not
    def test_mandatory_field(field, fieldname)
      if field.nil?
        show_usage
        ui.fatal("You must specify a #{fieldname}")
        exit 1
      end
    end

    def rest
      @rest ||= begin
        require "chef/server_api"
        Chef::ServerAPI.new(Chef::Config[:chef_server_url])
      end
    end

    def noauth_rest
      @rest ||= begin
        require "chef/http/simple_json"
        Chef::HTTP::SimpleJSON.new(Chef::Config[:chef_server_url])
      end
    end

    def server_url
      Chef::Config[:chef_server_url]
    end

    def maybe_setup_fips
      if !config[:fips].nil?
        Chef::Config[:fips] = config[:fips]
      end
      Chef::Config.init_openssl
    end
  end
end