(* for tls support replace [Irc_client_lwt] with [Irc_client_tls] *)
open Lwt
open Irccolors
module C = Irc_client_lwt

let logf : string -> unit Lwt.t = Lwt_io.printl
let formatf = Printf.sprintf

(***********************************)
(** * Options *)

let host = ref "localhost"
let port = ref 6667
let realname = ":3"
let botnick = ref "vantabot"
let channel = ref "#bots"
let username = botnick
let sleeptime = ref 30.
let countdown = ref 5
let db_file = ref "toke.db"

let options = Arg.align
  [ "-host", Arg.Set_string host, " server host name (default: " ^ !host ^ ")"
  ; "-port", Arg.Set_int port, " server port (default: " ^ string_of_int !port ^ ")"
  ; "-chan", Arg.Set_string channel, " target channel (default: " ^ !channel ^ ")"
  ; "-nick", Arg.Set_string botnick, " nick prefix (default: " ^ !botnick ^ ")"
  ; "-sleeptime", Arg.Set_float sleeptime, " time period for joining the toke call, in seconds (default: " ^ string_of_float !sleeptime ^ ")"
  ; "-countdown", Arg.Set_int countdown, " countdown, in seconds (default: " ^ string_of_int !countdown ^ ")"
  ; "-db", Arg.Set_string db_file, " database file, will be created if does not exist (default: " ^ !db_file ^ ")"
  ]

let sendmsg connection m = C.send_privmsg ~connection ~target:!channel ~message:(color_text ~fg:Green ~bg:Black m)

(** * BUSINESS LOGIC HEH *)

let toke_in_progress = ref false
let tokers = ref []

let push_toker t =
  let contents = !tokers in
  let cnd = not (List.mem t contents) in
  if cnd then tokers := t::contents;
  cnd

let tokeplz () =
  let r = String.concat " " !tokers in
  "SMOKE NOW " ^ r

let inc_tokers_count () =
  List.iter (fun n -> Store.register_nick n (Store.DB !db_file)) !tokers


let leaf = [
"        W        ";
"       WWW       ";
"       WWW       ";
"      WWWWW      ";
"W     WWWWW     W";
"WWW   WWWWW   WWW";
" WWW  WWWWW  WWW ";
"  WWW  WWW  WWW  ";
"   WWW WWW WWW   ";
"    WWWWWWW      ";  
"  WWWW  |  WWWW  ";
"        |        ";
"        |        "]

let show_leaf connection =
  leaf |> Lwt_list.iter_s (fun l -> sendmsg connection l)

let start_toke connection =
  toke_in_progress := true;
  let rec toker_thread n conn =
    if n = 0
    then begin
        let msg = tokeplz () in 
        inc_tokers_count ();
        tokers := [];
        sendmsg connection msg
        >>= fun () ->
        toke_in_progress := false;        
        show_leaf connection
      end
    else begin
        sendmsg connection (color_text ~bg:Black ~fg:White (formatf "ready in %i..." n))
        >>= fun () -> Lwt_unix.sleep 1.
        >>= fun () -> toker_thread (n-1) conn
      end
  in
  Lwt.async (fun () ->
      let slt = !sleeptime in
      (if slt > 10.
       then Lwt_unix.sleep (slt-.10.) >>= fun () ->
            sendmsg connection (color_text ~bg:Black ~fg:LightGreen "toke in ~10s") >>= fun () ->
            Lwt_unix.sleep 10.
       else Lwt_unix.sleep slt) >>= fun () ->
      toker_thread !countdown connection);
  sendmsg connection (formatf "Toke in progress, type in `!toke' to join. Time to go: ~%.1f secs" !sleeptime)

let handle_toke who conn =
  let is_new = push_toker who in
  if  (!toke_in_progress)
  then if is_new
       then sendmsg conn (formatf "%s joins the toke call" who)
       else return ()
  else start_toke conn

let rollcall ?who conn =
  let pref = match who with
      None -> ""
    | Some n -> n ^ ": " in
  sendmsg conn (pref ^ "vantabot is a bot for synchronized toking. See <https://tildegit.org/epicmorphism/vantabot>. TL;DR: the only command is !toke")

(***********************************)
(** * IRC connection handling code *)


let new_channel ~connection ~channel =
  C.send_join ~connection ~channel
  >>= fun () -> C.send_privmsg ~connection ~target:channel
                  ~message:(bold_text (color_text ~fg:Green ~bg:Black ".420."))

let nick_of_irc_message imsg =
  let open Irc_message in
  match imsg.prefix with
  | None -> None
  | Some wh ->
     match String.split_on_char '!' wh with
     | a::_ -> Some a
     | [] -> None
  

let callback connection result =
  let open Irc_message in
  match result with
  | Result.Error e -> logf (formatf "[callback] Error parsing a message: %s" e)
  | Result.Ok imsg ->
     logf (to_string imsg) >>= fun () ->
     (match imsg.command with
     | PRIVMSG (target, msg) ->
        if target = !channel && String.length msg > 4 then
          (* INITIATE OR JOIN THE TOKE *)
          if String.sub msg 0 5 = "!toke" then
            match nick_of_irc_message imsg with
            | None -> return ()
            | Some wh -> handle_toke wh connection
          (* RESPOND TO ROLLCALL *)
          else if msg = (!botnick) ^ ": rollcall" then
            match nick_of_irc_message imsg with
            | None -> return ()
            | Some wh -> rollcall ~who:wh connection
          else if msg = "!rollcall" then
            rollcall connection
          else return ()
        else return ()
     | _ -> return ())


let lwt_main () =
  C.set_log logf;
  C.reconnect_loop
    ~after:30
    ~connect:(fun () ->
      logf "Connecting..."
      >>= fun () -> C.connect_by_name ~realname:realname ~username:!username ~server:!host ~port:!port ~nick:!botnick ()
    )
    ~f:(fun connection ->
      logf "Connected"
      >>= fun () -> new_channel connection !channel)
    ~callback
    ()

let _ =
  Arg.parse options (fun _ -> ()) "<vantabot> [options]\n";
  Lwt_main.run (lwt_main ())