search: switch to new tag search parser in a few places.

app/components/post_navbar_component.rb

@@ -43,7 +43,7 @@ class PostNavbarComponent < ApplicationComponent
   end
 
   def query
-    @query ||= PostQueryBuilder.new(search)
+    @query ||= PostQuery.new(search)
   end
 
   memoize :favgroups

app/logical/bulk_update_request_processor.rb

@@ -116,10 +116,10 @@ class BulkUpdateRequestProcessor
           end
 
         when :mass_update
-          lhs = PostQueryBuilder.new(args[0])
-          rhs = PostQueryBuilder.new(args[1])
+          lhs = PostQuery.new(args[0])
+          rhs = PostQuery.new(args[1])
 
-          if lhs.is_simple_tag? && rhs.is_simple_tag?
+          if lhs.is_single_tag? && rhs.is_single_tag?
             errors.add(:base, "Can't mass update #{args[0]} -> #{args[1]} (use an alias or a rename instead for tag moves)")
           end
 
@@ -236,9 +236,8 @@ class BulkUpdateRequestProcessor
       when :mass_update
         "mass update {{#{args[0]}}} -> {{#{args[1]}}}"
       when :nuke
-        query = PostQueryBuilder.new(args[0])
 
-        if query.is_simple_tag?
+        if PostQuery.new(args[0]).is_single_tag?
           "nuke [[#{args[0]}]]"
         else
           "nuke {{#{args[0]}}}"
@@ -255,7 +254,7 @@ class BulkUpdateRequestProcessor
   def self.nuke(tag_name)
     # Reject existing implications from any other tag to the one we're nuking
     # otherwise the tag won't be removed from posts that have those other tags
-    if PostQueryBuilder.new(tag_name).is_simple_tag?
+    if PostQuery.new(tag_name).is_single_tag?
       TagImplication.active.where(consequent_name: tag_name).each { |ti| ti.reject!(User.system) }
       TagImplication.active.where(antecedent_name: tag_name).each { |ti| ti.reject!(User.system) }
     end

app/logical/post_query.rb

@@ -4,7 +4,7 @@ class PostQuery
   extend Memoist
 
   attr_reader :search, :parser, :ast
-  delegate :tag_names, to: :ast
+  delegate :tag_names, :metatags, to: :ast
 
   def initialize(search)
     @search = search
@@ -16,5 +16,21 @@ class PostQuery
     Tag.where(name: tag_names)
   end
 
+  def is_single_tag?
+    ast.tag?
+  end
+
+  def select_metatags(*names)
+    metatags.select { |metatag| metatag.name.in?(names.map(&:to_s).map(&:downcase)) }
+  end
+
+  def has_metatag?(*names)
+    select_metatags(*names).present?
+  end
+
+  def find_metatag(*names)
+    select_metatags(*names).first&.value
+  end
+
   memoize :tags
 end