(********************************************************************)
(*                                                                  *)
(*  The Why3 Verification Platform   /   The Why3 Development Team  *)
(*  Copyright 2010-2023 --  Inria - CNRS - Paris-Saclay University  *)
(*                                                                  *)
(*  This software is distributed under the terms of the GNU Lesser  *)
(*  General Public License version 2.1, with the special exception  *)
(*  on linking described in file LICENSE.                           *)
(*                                                                  *)
(********************************************************************)

open Format
open Why3

let () = Debug.set_flag Glob.flag

(* command line parsing *)

let usage_msg = "<file>...\nProduce HTML documentation for the given files."

let opt_output = ref None
let opt_index = ref None (* default behavior *)
let opt_title = ref None
let opt_body = ref false
let opt_queue = Queue.create ()

let option_list =
  let open Getopt in
  [ Key ('o', "output"), Hnd1 (AString, fun s -> opt_output := Some s),
    "<dir> print files in <dir>";
    KLong "stdlib-url", Hnd1 (AString, Doc_def.set_stdlib_url),
    "<url> add links to <url> for files found on loadpath";
    KLong "index", Hnd0 (fun () -> opt_index := Some true),
    " generate an index file index.html";
    KLong "no-index", Hnd0 (fun () -> opt_index := Some false),
    " do not generate an index file index.html";
    KLong "title", Hnd1 (AString, fun s -> opt_title := Some s),
    "<title> set a title for the index page";
    KLong "body-only", Hnd0 (fun () -> opt_body := true),
    " only produce the body of the HTML document";
  ]

let _,env =
  Whyconf.Args.initialize option_list
    (fun x -> Queue.add x opt_queue) usage_msg

let index = match !opt_index with
  | Some b -> b
  | None -> Queue.length opt_queue > 1

let title = match !opt_title with
  | None -> "why3doc index"
  | Some s -> s

let css =
  let css_fname = "style.css" in
  let css_full_fname = match !opt_output with
    | None -> css_fname
    | Some dir -> Filename.concat dir css_fname
  in
  if not (Sys.file_exists css_full_fname)
  then Doc_html.style_css css_full_fname;
  css_fname

let do_file env fname =
  let glob = Glob.drop fname in
  begin try
    ignore (Env.read_file Env.base_language env fname)
  with e ->
    eprintf "error: could not read file '%s'@." fname;
    eprintf "(%a)@." Exn_printer.exn_printer e;
    exit 1
  end;
  let fhtml = Doc_def.output_file fname in
  let c = open_out fhtml in
  let fmt = formatter_of_out_channel c in
  let f = Filename.basename fhtml in
  if not !opt_body then Doc_html.print_header fmt ~title:f ~css ();
  if index then
    fprintf fmt "<p>%s <a href=\"index.html\">index</a></p>@\n<hr>@\n" title;
  Doc_lexer.do_file fmt fname;
  if not !opt_body then Doc_html.print_footer fmt ();
  pp_print_flush fmt ();
  close_out c;
  (* all the identifiers associated to fname needs to be cleared,
     as they might also be available through option -L *)
  Glob.restore fname glob

let () =
  Queue.iter Doc_def.add_local_file opt_queue;
  try
    Doc_def.set_output_dir !opt_output;
    (* process files *)
    Queue.iter (do_file env) opt_queue;
    (* then generate the index *)
    if index then begin
      let fhtml = Doc_def.output_file "index.why" in
      let c = open_out fhtml in
      let fmt = formatter_of_out_channel c in
      if not !opt_body then Doc_html.print_header fmt ~title ~css ();
      fprintf fmt "<div class=\"why3doc\">@\n";
      fprintf fmt "<h1>%s</h1>@\n" title;
      fprintf fmt "<ul>@\n";
      let add fn =
        let header = Doc_lexer.extract_header fn in
        let header = if header = "" then "" else ": " ^ header in
        let fhtml = Doc_def.output_file fn in
        let basename = Filename.basename fhtml in
        fprintf fmt "<li> <a href=\"%s\">%s</a> %s </li>@\n"
          basename (Filename.chop_extension basename) header
      in
      Queue.iter add opt_queue;
      fprintf fmt "</ul>@\n";
      fprintf fmt "</div>@\n";
      if not !opt_body then Doc_html.print_footer fmt ();
      close_out c
    end
  with e when not (Debug.test_flag Debug.stack_trace) ->
    eprintf "%a@." Exn_printer.exn_printer e;
    exit 1
