#
# MACROS
# these are methods available when eval'ing a value in the .json configuration
#
# This module is included in Config::Object
#

module LeapCli; module Config
  module Macros
    ##
    ## NODES
    ##

    #
    # the list of all the nodes
    #
    def nodes
      global.nodes
    end

    #
    # returns a list of nodes that match the same environment
    #
    def nodes_like_me
      nodes[:environment => @node.environment]
    end

    ##
    ## FILES
    ##

    class FileMissing < Exception
      attr_accessor :path, :options
      def initialize(path, options={})
        @path = path
        @options = options
      end
      def to_s
        @path
      end
    end

    #
    # inserts the contents of a file
    #
    def file(filename, options={})
      if filename.is_a? Symbol
        filename = [filename, @node.name]
      end
      filepath = Path.find_file(filename)
      if filepath
        if filepath =~ /\.erb$/
          ERB.new(File.read(filepath), nil, '%<>').result(binding)
        else
          File.read(filepath)
        end
      else
        raise FileMissing.new(Path.named_path(filename), options)
        ""
      end
    end

    #
    # like #file, but allow missing files
    #
    def try_file(filename)
      return file(filename)
    rescue FileMissing
      return nil
    end

    #
    # returns what the file path will be, once the file is rsynced to the server.
    # an internal list of discovered file paths is saved, in order to rsync these files when needed.
    #
    # notes:
    #
    # * argument 'path' is relative to Path.provider/files or Path.provider_base/files
    # * the path returned by this method is absolute
    # * the path stored for use later by rsync is relative to Path.provider
    # * if the path does not exist locally, but exists in provider_base, then the default file from
    #   provider_base is copied locally. this is required for rsync to work correctly.
    #
    def file_path(path)
      if path.is_a? Symbol
        path = [path, @node.name]
      end
      actual_path = Path.find_file(path)
      if actual_path.nil?
        Util::log 2, :skipping, "file_path(\"#{path}\") because there is no such file."
        nil
      else
        if actual_path =~ /^#{Regexp.escape(Path.provider_base)}/
          # if file is under Path.provider_base, we must copy the default file to
          # to Path.provider in order for rsync to be able to sync the file.
          local_provider_path = actual_path.sub(/^#{Regexp.escape(Path.provider_base)}/, Path.provider)
          FileUtils.mkdir_p File.dirname(local_provider_path)
          FileUtils.cp_r actual_path, local_provider_path
          Util.log :created, Path.relative_path(local_provider_path)
          actual_path = local_provider_path
        end
        if File.directory?(actual_path) && actual_path !~ /\/$/
          actual_path += '/' # ensure directories end with /, important for building rsync command
        end
        relative_path = Path.relative_path(actual_path)
        @node.file_paths << relative_path
        @node.manager.provider.hiera_sync_destination + '/' + relative_path
      end
    end

    #
    # inserts a named secret, generating it if needed.
    #
    # manager.export_secrets should be called later to capture any newly generated secrets.
    #
    def secret(name, length=32)
      @manager.secrets.set(name, Util::Secret.generate(length))
    end

    #
    # return a fingerprint for a x509 certificate
    #
    def fingerprint(filename)
      "SHA256: " + X509.fingerprint("SHA256", Path.named_path(filename))
    end

    ##
    ## HOSTS
    ##

    #
    # records the list of hosts that are encountered for this node
    #
    def hostnames(nodes)
      @referenced_nodes ||= ObjectList.new
      if nodes.is_a? Config::Object
        nodes = ObjectList.new nodes
      end
      nodes.each_node do |node|
        @referenced_nodes[node.name] = node
      end
      nodes.values.collect {|node| node.domain.name}
    end

    #
    # generates entries needed for updating /etc/hosts on a node, but only including the IPs of the
    # other nodes we have encountered.
    #
    def hosts_file
      return nil unless @referenced_nodes
      entries = []
      @referenced_nodes.each_node do |node|
        entries << "#{node.ip_address}    #{node.name} #{node.domain.internal} #{node.domain.full}"
      end
      entries.join("\n")
    end

    def known_hosts_file
      return nil unless @referenced_nodes
      entries = []
      @referenced_nodes.each_node do |node|
        hostnames = [node.name, node.domain.internal, node.domain.full, node.ip_address].join(',')
        pub_key   = Util::read_file([:node_ssh_pub_key,node.name])
        if pub_key
          entries << [hostnames, pub_key].join(' ')
        end
      end
      entries.join("\n")
    end

    ##
    ## STUNNEL
    ##

    #
    # stunnel configuration for the client side.
    #
    # +node_list+ is a ObjectList of nodes running stunnel servers.
    #
    # +port+ is the real port of the ultimate service running on the servers
    # that the client wants to connect to.
    #
    # About ths stunnel puppet names:
    #
    # * accept_port is the port on localhost to which local clients
    #   can connect. it is auto generated serially.
    # * connect_port is the port on the stunnel server to connect to.
    #   it is auto generated from the +port+ argument.
    #
    #  The network looks like this:
    #
    #  |------ stunnel client ---------------| |--------- stunnel server -----------------------|
    #  consumer app -> localhost:accept_port -> server:connect_port -> server:port -> service app
    #
    # generates an entry appropriate to be passed directly to
    # create_resources(stunnel::service, hiera('..'), defaults)
    #
    def stunnel_client(node_list, port, options={})
      @next_stunnel_port ||= 4000
      node_list.values.inject(Config::ObjectList.new) do |hsh, node|
        if node.name != self.name || options[:include_self]
          hsh["#{node.name}#{port}"] = Config::Object[
            'accept_port', @next_stunnel_port,
            'connect', node.domain.internal,
            'connect_port', stunnel_port(port)
          ]
          @next_stunnel_port += 1
        end
        hsh
      end
    end

    #
    # generates a stunnel server entry.
    #
    # +port+ is the real port targeted service.
    #
    def stunnel_server(port)
      {"accept" => stunnel_port(port), "connect" => "127.0.0.1:#{port}"}
    end

    #
    # maps a real port to a stunnel port (used as the connect_port in the client config
    # and the accept_port in the server config)
    #
    def stunnel_port(port)
      port = port.to_i
      if port < 50000
        return port + 10000
      else
        return port - 10000
      end
    end

  end
end; end