(*
 * Copyright (c) 2009-2013, Monoidics ltd.
 * Copyright (c) 2013-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *)

open! IStd
open Javalib_pack
open Sawja_pack

(** data structure for representing whether an instruction is a goto, a return or a standard instruction.   *)
type jump_kind = Next | Jump of int | Exit

(** Hastable for storing nodes that correspond to if-instructions. These are
    used when adding the edges in the contrl flow graph. *)
module NodeTbl : Caml.Hashtbl.S with type key = Procdesc.Node.t

(** data structure for saving the three structures tht contain the intermediate
    representation of a file: the type environment, the control graph and the control
    flow graph *)
type icfg = {tenv: Tenv.t; cfg: Cfg.t}

(** data structure for storing the context elements.  *)
type t = private
  { icfg: icfg
  ; procdesc: Procdesc.t
  ; impl: JBir.t
  ; mutable var_map: (Pvar.t * Typ.t * Typ.t) JBir.VarMap.t
  ; if_jumps: int NodeTbl.t
  ; goto_jumps: (int, jump_kind) Caml.Hashtbl.t
  ; cn: JBasics.class_name
  ; source_file: SourceFile.t
  ; program: JClasspath.program }

val create_context :
  icfg -> Procdesc.t -> JBir.t -> JBasics.class_name -> SourceFile.t -> JClasspath.program -> t
(** cretes a context for a given method.   *)

val get_tenv : t -> Tenv.t
(** returns the type environment that corresponds to the current file. *)

val add_if_jump : t -> Procdesc.Node.t -> int -> unit
(** adds to the context the line that an if-node will jump to *)

val get_if_jump : t -> Procdesc.Node.t -> int option
(** returns whether the given node corresponds to an if-instruction *)

val add_goto_jump : t -> int -> jump_kind -> unit
(** adds to the context the line that the node in the given line will jump to. *)

val get_goto_jump : t -> int -> jump_kind
(** if the given line corresponds to a goto instruction, then returns the
    line where it jumps to, otherwise returns the next line. *)

val is_goto_jump : t -> int -> bool
(** returns whether the given line corresponds to a goto instruction.  *)

val set_pvar : t -> JBir.var -> Typ.t -> Pvar.t
(** [set_pvar context var type] adds a variable with a type to the context  *)

val get_var_type : t -> JBir.var -> Typ.t option
(** [get_var_type context var] returns the type of the variable, if the variable is in the context *)

val reset_pvar_type : t -> unit
(** resets the dynamic type of the variables in the context. *)

val reset_exn_node_table : unit -> unit
(** resets the hashtable mapping methods to their exception nodes  *)

val add_exn_node : Typ.Procname.t -> Procdesc.Node.t -> unit
(** adds the exception node for a given method *)