open Cmdliner
open Cmdliner.Term.Syntax

let version_string () =
  match Build_info.V1.version () with
  | None -> "dev"
  | Some v -> Build_info.V1.Version.to_string v

let files =
  let doc = "Files to process" in
  Arg.(non_empty & pos_all string [] & info [] ~docv:"FILE" ~doc)

let timezone =
  let doc = "Target timezone for output (e.g. Europe/Rome). Defaults to local timezone." in
  Arg.(value & opt (some string) None & info [ "timezone"; "z" ] ~docv:"TZ" ~doc)

let verbose =
  let doc = "Print diagnostic messages (skipped events, unsupported recurrences, etc.) on stderr." in
  Arg.(value & flag & info [ "verbose"; "v" ] ~doc)

let no_uuid =
  let doc = "Omit the INFO line with the event UID from output." in
  Arg.(value & flag & info [ "no-uuid" ] ~doc)

let no_source =
  let doc = "Omit the INFO line with the calendar source name from output." in
  Arg.(value & flag & info [ "no-source" ] ~doc)

let no_location =
  let doc = "Omit the INFO line with the event location from output." in
  Arg.(value & flag & info [ "no-location" ] ~doc)

let no_description =
  let doc = "Omit the INFO line with the event description from output." in
  Arg.(value & flag & info [ "no-description" ] ~doc)

let no_conference_url =
  let doc = "Omit the INFO line with the conference URL from output." in
  Arg.(value & flag & info [ "no-conference-url" ] ~doc)

type sort_order = Asc | Desc | Original

let sort_order_enum = [ ("asc", Asc); ("desc", Desc); ("original", Original) ]

let sort =
  let doc = "Output sort order by date: $(b,desc) (default), $(b,asc), or $(b,none) (file order)." in
  Arg.(value & opt (enum sort_order_enum) Desc & info [ "sort" ] ~docv:"ORDER" ~doc)

let source =
  let doc = "Override the calendar source name used in INFO lines. Only valid when processing a single file." in
  Arg.(value & opt (some string) None & info [ "source" ] ~docv:"NAME" ~doc)

type cli_args = {
  tz : string option;
  verbose : bool;
  no_uuid : bool;
  no_source : bool;
  no_location : bool;
  no_description : bool;
  no_conference_url : bool;
  sort : sort_order;
  source : string option;
}

let main_command f =
  let doc = "Convert iCalendar files to remind format" in
  let man = [] in
  Cmd.make (Cmd.info "ical2rem" ~version:(version_string ()) ~doc ~man)
  @@
  let+ files = files
  and+ tz = timezone
  and+ verbose = verbose
  and+ no_uuid = no_uuid
  and+ no_source = no_source
  and+ no_location = no_location
  and+ no_description = no_description
  and+ no_conference_url = no_conference_url
  and+ sort = sort
  and+ source = source in
  f { tz; verbose; no_uuid; no_source; no_location; no_description; no_conference_url; sort; source } files

let main f = Cmd.eval @@ main_command f