open Remind_sync
open Utils

type rem = {
  original_uuid : string;  (** Original UID from the iCalendar event *)
  summary : string;  (** Summary or title of the reminder *)
  date : Timedesc.Date.t;  (** Date specification (day, month, year) *)
  end_date : Timedesc.Date.t option;  (** Optional end date for a date range *)
  time : Timedesc.Time.t option;  (** Optional time specification (hour, minute) *)
  duration : Timedesc.Span.t option;  (** Optional duration for timed events *)
  simple_yearly : (int * int) option;  (** Optional simple yearly recurrence (month, day) *)
  recurring : Icalendar.event list;
      (** List of events that are part of the same recurring series: these are only the overrides, not the master event
      *)
}
[@@deriving show]
(** A complete REM command *)

let empty =
  {
    original_uuid = "";
    summary = "";
    date = Timedesc.Date.Ymd.make_exn ~year:1970 ~month:1 ~day:1;
    end_date = None;
    time = None;
    duration = None;
    simple_yearly = None;
    recurring = [];
  }

let render_simple_yearly month day summary =
  let month_str = month_of_int month |> string_of_month in
  spf "REM %s %d MSG %s" month_str day summary

let string_of_rem rem =
  match rem.simple_yearly with
  | Some (month, day) -> render_simple_yearly month day rem.summary
  | None -> begin
      let b = Buffer.create 256 in
      Buffer.add_string b "REM ";
      Buffer.add_string b (spf "INFO \"UID: %s\" " rem.original_uuid);
      Buffer.add_string b (Timedesc.Date.to_rfc3339 rem.date);
      (match rem.time with
      | Some time ->
          Buffer.add_string b " AT ";
          Buffer.add_string b (string_of_time time)
      | None -> ());
      (match rem.duration with
      | Some duration ->
          Buffer.add_string b " DURATION ";
          Buffer.add_string b (string_of_span duration);
          Buffer.add_string b ""
      | None -> ());
      (match rem.end_date with
      | Some end_date ->
          Buffer.add_string b " THROUGH ";
          Buffer.add_string b (Timedesc.Date.to_rfc3339 end_date)
      | None -> ());
      Buffer.add_string b " MSG ";
      Buffer.add_string b rem.summary;
      Buffer.contents b
    end