(*
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *)

open! IStd

(** Module for error logs. *)

type node_tag =
  | Condition of bool
  | Exception of Typ.name
  | Procedure_start of Procname.t
  | Procedure_end of Procname.t

(** Element of a loc trace *)
type loc_trace_elem = private
  { lt_level: int  (** nesting level of procedure calls *)
  ; lt_loc: Location.t  (** source location at the current step in the trace *)
  ; lt_description: string  (** description of the current step in the trace *)
  ; lt_node_tags: node_tag list  (** tags describing the node at the current location *) }

val make_trace_element : int -> Location.t -> string -> node_tag list -> loc_trace_elem
(** build a loc_trace_elem from its constituents (unambiguously identified by their types). *)

(** Trace of locations *)
type loc_trace = loc_trace_elem list

val concat_traces : (string * loc_trace) list -> loc_trace

val compute_local_exception_line : loc_trace -> int option
(** Look at all the trace steps and find those that are arising any exception, then bind them to the
    closest step at level 0. This extra information adds value to the report itself, and may avoid
    digging into the trace to understand the cause of the report. *)

type node =
  | UnknownNode
  | FrontendNode of {node_key: Procdesc.NodeKey.t}
  | BackendNode of {node: Procdesc.Node.t}

type err_key = private
  {severity: Exceptions.severity; err_name: IssueType.t; err_desc: Localise.error_desc}
[@@deriving compare]

val merge_err_key :
     err_key
  -> err_key
  -> merge_issues:(IssueType.t -> IssueType.t -> IssueType.t)
  -> merge_descriptions:(string list -> string list -> string)
  -> err_key
(** Merges two error keys, setting the result's severity to the maximum of that of the two arguments
    and giving the user the opportunity to pass a function to merge the IssueTypes and descriptions
    of the two. *)

(** Data associated to a specific error *)
type err_data = private
  { node_id: int
  ; node_key: Procdesc.NodeKey.t option
  ; session: int
  ; loc: Location.t
  ; loc_in_ml_source: Logging.ocaml_pos option
  ; loc_trace: loc_trace
  ; err_class: Exceptions.err_class
  ; visibility: Exceptions.visibility
  ; linters_def_file: string option
  ; doc_url: string option  (** url to documentation of the issue type *)
  ; access: string option
  ; extras: Jsonbug_t.extra option }
[@@deriving compare]

val merge_err_data : err_data -> err_data -> err_data
(** Merges two err_datas, throwing out most information and setting the trace of the result to the
    concatenation of the traces of the two arguments with a separator in between. Used specifically
    for QuandaryBO. *)

(** Type of the error log *)
type t

val empty : unit -> t
(** Empty error log *)

(** type of the function to be passed to iter *)
type iter_fun = err_key -> err_data -> unit

val iter : iter_fun -> t -> unit
(** Apply f to nodes and error names *)

val fold : (err_key -> err_data -> 'a -> 'a) -> t -> 'a -> 'a

val pp_loc_trace_elem : Format.formatter -> loc_trace_elem -> unit [@@warning "-32"]

val pp_loc_trace : Format.formatter -> loc_trace -> unit

val pp_errors : Format.formatter -> t -> unit
(** Print errors from error log *)

val pp_warnings : Format.formatter -> t -> unit
(** Print warnings from error log *)

val pp_html : SourceFile.t -> DB.Results_dir.path -> Format.formatter -> t -> unit
(** Print an error log in html format *)

val size : (Exceptions.severity -> bool) -> t -> int
(** Return the number of elements in the error log which satisfy the filter. *)

val update : t -> t -> unit
(** Update an old error log with a new one *)

val log_issue :
     Procname.t
  -> clang_method_kind:ClangMethodKind.t option
  -> Exceptions.severity
  -> t
  -> loc:Location.t
  -> node:node
  -> session:int
  -> ltr:loc_trace
  -> linters_def_file:string option
  -> doc_url:string option
  -> access:string option
  -> extras:Jsonbug_t.extra option
  -> exn
  -> unit