%% This Source Code Form is subject to the terms of the Mozilla Public
%% License, v. 2.0. If a copy of the MPL was not distributed with this
%% file, You can obtain one at https://mozilla.org/MPL/2.0/.
%%
%% Copyright (c) 2018-2023 VMware, Inc. or its affiliates.  All rights reserved.
%%

-module(vhost).

-include_lib("rabbit_common/include/rabbit.hrl").
-include("vhost.hrl").

-export([
  new/2,
  new/3,
  fields/0,
  fields/1,
  info_keys/0,
  record_version_to_use/0,
  upgrade/1,
  upgrade_to/2,
  pattern_match_all/0,
  get_name/1,
  get_limits/1,
  get_metadata/1,
  get_description/1,
  get_tags/1,
  get_default_queue_type/1,
  set_limits/2,
  set_metadata/2,
  merge_metadata/2,
  is_tagged_with/2
]).

-define(record_version, vhost_v2).

-type(name() :: rabbit_types:vhost()).

-type(metadata_key() :: atom()).

-type(metadata() :: #{description => binary(),
                      tags => [atom()],
                      metadata_key() => any()} | undefined).

-type(description() :: binary()).
-type(tag() :: atom()).
-type(tags() :: [tag()]).
-type(unparsed_tags() :: binary() | string() | atom()).

-type vhost() :: vhost_v2().

-record(vhost, {
    %% name as a binary
    virtual_host :: name() | '_',
    %% proplist of limits configured, if any
    limits :: list() | '_',
    metadata :: metadata() | '_'
}).

-type vhost_v2() :: #vhost{
                          virtual_host :: name(),
                          limits :: list(),
                          metadata :: metadata()
                         }.

-type vhost_pattern() :: vhost_v2_pattern().
-type vhost_v2_pattern() :: #vhost{
                                  virtual_host :: name() | '_',
                                  limits :: '_',
                                  metadata :: '_'
                                 }.

-export_type([name/0,
              metadata_key/0,
              metadata/0,
              description/0,
              tag/0,
              unparsed_tags/0,
              tags/0,
              vhost/0,
              vhost_v2/0,
              vhost_pattern/0,
              vhost_v2_pattern/0]).

-spec new(name(), list()) -> vhost().
new(Name, Limits) ->
    #vhost{virtual_host = Name, limits = Limits}.

-spec new(name(), list(), map()) -> vhost().
new(Name, Limits, Metadata) ->
    #vhost{virtual_host = Name, limits = Limits, metadata = Metadata}.

-spec record_version_to_use() -> vhost_v2.

record_version_to_use() ->
    ?record_version.

-spec upgrade(vhost()) -> vhost().

upgrade(#vhost{} = VHost) -> VHost.

-spec upgrade_to(vhost_v2, vhost()) -> vhost_v2().

upgrade_to(?record_version, #vhost{} = VHost) ->
    VHost.

fields() ->
    fields(?record_version).

fields(?record_version) -> record_info(fields, vhost).

info_keys() ->
    %% note: this reports description and tags separately even though
    %% they are stored in the metadata map. MK.
    [name,
     description,
     tags,
     default_queue_type,
     metadata,
     tracing,
     cluster_state].

-spec pattern_match_all() -> vhost_pattern().

pattern_match_all() ->
    #vhost{_ = '_'}.

-spec get_name(vhost()) -> name().
get_name(#vhost{virtual_host = Value}) -> Value.

-spec get_limits(vhost()) -> list().
get_limits(#vhost{limits = Value}) -> Value.

-spec get_metadata(vhost()) -> metadata().
get_metadata(#vhost{metadata = Value}) -> Value.

-spec get_description(vhost()) -> binary().
get_description(#vhost{} = VHost) ->
    maps:get(description, get_metadata(VHost), undefined).

-spec get_tags(vhost()) -> [atom()].
get_tags(#vhost{} = VHost) ->
    maps:get(tags, get_metadata(VHost), []).

-spec get_default_queue_type(vhost()) -> binary() | undefined.
get_default_queue_type(#vhost{} = VHost) ->
    maps:get(default_queue_type, get_metadata(VHost), undefined);
get_default_queue_type(_VHost) ->
    undefined.

set_limits(VHost, Value) ->
    VHost#vhost{limits = Value}.

-spec set_metadata(vhost(), metadata()) -> vhost().
set_metadata(VHost, Value) ->
    VHost#vhost{metadata = Value}.

-spec merge_metadata(vhost(), metadata()) -> vhost().
merge_metadata(VHost, Value) ->
    Meta0 = get_metadata(VHost),
    NewMeta = maps:merge(Meta0, Value),
    VHost#vhost{metadata = NewMeta}.

-spec is_tagged_with(vhost:vhost(), atom()) -> boolean().
is_tagged_with(VHost, Tag) ->
    lists:member(Tag, get_tags(VHost)).
