Статистика для дашборда, расширенная #7

src/core/core_ticket.erl

@@ -8,6 +8,7 @@
   create_ticket/1,
   list_by_user/1]).
 -export([count_tickets_by_status/1, count_tickets_by_admin/2]).
+-export([avg_resolution_time/0]).
 
 list_all() ->
   mnesia:dirty_match_object(#ticket{_ = '_'}).
@@ -69,6 +70,27 @@ create_ticket(Data) ->
 list_by_user(UserId) ->
   mnesia:dirty_match_object(#ticket{reporter_id = UserId, _ = '_'}).
 
+count_by_status(Status, Tickets) ->
+  length([T || T <- Tickets, T#ticket.status =:= Status]).
+
+count_tickets_by_status(Status) ->
+  Match = #ticket{status = Status, _ = '_'},
+  length(mnesia:dirty_match_object(Match)).
+
+count_tickets_by_admin(AdminId, Status) ->
+  Match = #ticket{assigned_to = AdminId, status = Status, _ = '_'},
+  length(mnesia:dirty_match_object(Match)).
+
+avg_resolution_time() ->
+  Tickets = mnesia:dirty_match_object(#ticket{status = closed, _ = '_'}),
+  case Tickets of
+    [] -> 0;
+    _ ->
+      TotalSeconds = lists:sum([calendar:datetime_to_gregorian_seconds(T#ticket.last_seen) -
+        calendar:datetime_to_gregorian_seconds(T#ticket.first_seen) || T <- Tickets]),
+      TotalSeconds / length(Tickets) / 3600.0
+  end.
+
 %% ── внутренние ─────────────────────────────────────────
 apply_updates(Ticket, Updates) ->
   lists:foldl(fun({Key, Value}, Acc) ->
@@ -81,15 +103,4 @@ apply_updates(Ticket, Updates) ->
       <<"context">>         -> Acc#ticket{context = Value};
       _                     -> Acc
     end
-              end, Ticket, maps:to_list(Updates)).
-
-count_by_status(Status, Tickets) ->
-  length([T || T <- Tickets, T#ticket.status =:= Status]).
-
-count_tickets_by_status(Status) ->
-  Match = #ticket{status = Status, _ = '_'},
-  length(mnesia:dirty_match_object(Match)).
-
-count_tickets_by_admin(AdminId, Status) ->
-  Match = #ticket{assigned_to = AdminId, status = Status, _ = '_'},
-  length(mnesia:dirty_match_object(Match)).
+              end, Ticket, maps:to_list(Updates)).