From 047e02c9ba1800b3080d0649a12910695ba5724f Mon Sep 17 00:00:00 2001
From: "Liam P. White" <byteslice@airmail.cc>
Date: Wed, 28 Aug 2019 21:14:54 -0400
Subject: [PATCH] some filter incorporation

---
 lib/philomena/images/query.ex                 | 18 +++++++++++++
 lib/philomena/search/lexer.ex                 |  2 +-
 lib/philomena/search/parser.ex                |  2 ++
 lib/philomena_web.ex                          |  1 +
 .../controllers/image_controller.ex           | 17 ++++--------
 lib/philomena_web/plugs/image_filter.ex       | 27 +++++++++++++++++++
 6 files changed, 54 insertions(+), 13 deletions(-)
 create mode 100644 lib/philomena_web/plugs/image_filter.ex

diff --git a/lib/philomena/images/query.ex b/lib/philomena/images/query.ex
index 8523d7db..d1abd431 100644
--- a/lib/philomena/images/query.ex
+++ b/lib/philomena/images/query.ex
@@ -170,4 +170,22 @@ defmodule Philomena.Images.Query do
     },
     default: "namespaced_tags.name"
   )
+
+  def compile(user, query_string, watch \\ false) do
+    query_string = query_string || ""
+
+    case user do
+      nil ->
+        anonymous_parser(%{user: nil, watch: watch}, query_string)
+
+      %{role: role} when role in ~W(user assistant) ->
+        user_parser(%{user: user, watch: watch}, query_string)
+
+      %{role: role} when role in ~W(moderator admin) ->
+        moderator_parser(%{user: user, watch: watch}, query_string)
+
+      _ ->
+        raise ArgumentError, "Unknown user role."
+    end
+  end
 end
diff --git a/lib/philomena/search/lexer.ex b/lib/philomena/search/lexer.ex
index 83b21fe7..2d871640 100644
--- a/lib/philomena/search/lexer.ex
+++ b/lib/philomena/search/lexer.ex
@@ -459,7 +459,7 @@ defmodule Philomena.Search.Lexer do
         ])
 
       search =
-        times(outer, min: 1)
+        repeat(outer)
         |> eos()
 
       defparsec(unquote(:"#{name}_lexer"), search)
diff --git a/lib/philomena/search/parser.ex b/lib/philomena/search/parser.ex
index 9467c6ab..271a8a33 100644
--- a/lib/philomena/search/parser.ex
+++ b/lib/philomena/search/parser.ex
@@ -35,6 +35,8 @@ defmodule Philomena.Search.Parser do
       # Predictive LL(k) parser for search grammar
       #
 
+      defp unquote(:"#{name}_top")(_ctx, []), do: {%{match_none: %{}}, []}
+
       defp unquote(:"#{name}_top")(ctx, tokens), do: unquote(:"#{name}_or")(ctx, tokens)
 
       #
diff --git a/lib/philomena_web.ex b/lib/philomena_web.ex
index 8d668dff..1359c2e4 100644
--- a/lib/philomena_web.ex
+++ b/lib/philomena_web.ex
@@ -24,6 +24,7 @@ defmodule PhilomenaWeb do
       import Plug.Conn
       import PhilomenaWeb.Gettext
       alias PhilomenaWeb.Router.Helpers, as: Routes
+      alias PhilomenaWeb.Plugs.ImageFilter
     end
   end
 
diff --git a/lib/philomena_web/controllers/image_controller.ex b/lib/philomena_web/controllers/image_controller.ex
index d9503d54..9db64f60 100644
--- a/lib/philomena_web/controllers/image_controller.ex
+++ b/lib/philomena_web/controllers/image_controller.ex
@@ -4,22 +4,15 @@ defmodule PhilomenaWeb.ImageController do
   alias Philomena.{Images, Images.Image}
   import Ecto.Query
 
+  plug ImageFilter
+
   def index(conn, _params) do
+    query = conn.assigns[:compiled_filter]
     images =
       Image.search_records(
         %{
-          query: %{
-            bool: %{
-              must_not: %{
-                terms: %{
-                  tag_ids: conn.assigns[:current_filter].hidden_tag_ids
-                }
-              }
-            }
-          },
-          sort: %{
-            created_at: :desc
-          }
+          query: %{bool: %{must_not: query}},
+          sort: %{created_at: :desc}
         },
         Image |> preload(:tags)
       )
diff --git a/lib/philomena_web/plugs/image_filter.ex b/lib/philomena_web/plugs/image_filter.ex
new file mode 100644
index 00000000..2a6131ad
--- /dev/null
+++ b/lib/philomena_web/plugs/image_filter.ex
@@ -0,0 +1,27 @@
+defmodule PhilomenaWeb.Plugs.ImageFilter do
+  import Plug.Conn
+
+  alias Philomena.Images.Query
+  alias Pow.Plug
+
+  # No options
+  def init([]), do: false
+
+  # Assign current filter
+  def call(conn, _opts) do
+    user = conn |> Plug.current_user()
+    filter = conn.assigns[:current_filter]
+
+    tag_exclusion = %{terms: %{tag_ids: filter.hidden_tag_ids}}
+    {:ok, query_exclusion} = Query.compile(user, filter.hidden_complex_str)
+
+    query = %{
+      bool: %{
+        should: [tag_exclusion, query_exclusion]
+      }
+    }
+
+    conn
+    |> assign(:compiled_filter, query)
+  end
+end