module Opts = struct
	open Arg

	type lasttype = NAME | SYMB | NUMB

	(** Positional arguments search based on the last type searched. *)
	let ltype = ref NAME

	(** Json file that generates the Sqlite3 database. *)
	let jsonf = ref ""

	(** Limit the amount of matches. *)
	let maxmatch = ref 1

	(** Lists to search. *)

	let match_name : string list ref = ref []
	let match_symb : string list ref = ref []
	let match_numb : int list ref = ref []

	let dbfile = ref "elements.sqlite3"

	let add_name s =
		match_name := s::!match_name;
		ltype := NAME
	let add_symb s =
		match_symb := s::!match_symb;
		ltype := SYMB
	let add_numb i =
		match_numb := i::!match_numb;
		ltype := NUMB
	let add_def s = match !ltype with
	| NAME -> add_name s
	| SYMB -> add_symb s
	| NUMB -> add_numb (match int_of_string_opt s with
		| None -> raise (Bad (Printf.sprintf "expected integer, got '%s'" s))
		| Some x -> x
	)

	let msg = "Periodic table search\n\
		elements -gendb file [-dbfile outfile]\n\
		elements [-maxmatch n] [-dbfile search] [-name ...] [-symb ...]\n\
	"

	let setfile name v f =
		if f = "" then raise
			(Bad (Printf.sprintf "%s requires a filename" name))
		else v := f

	let spec = [
	"-gendb", String (setfile "-gendb" jsonf), "Generate DB file";
	"-maxmatch", Set_int maxmatch, "Limit the amount of matches (def. 3)";
	"-dbfile", String (setfile "-dbfile" dbfile), "Set the DB filename";
	"-name", String add_name, "Search by name (default)";
	"-symb", String add_symb, "Search by symbol";
	"-num", Int add_numb, "Search by atomic number"
	]

	let exec() = parse spec add_def msg
end

let () = Opts.exec()

let db = Sqlite3.db_open !Opts.dbfile
let _ = if !Opts.jsonf <> "" then
	Makedb.makedb db (if !Opts.jsonf = "-" then
			Yojson.Basic.from_channel stdin
		 else
			Yojson.Basic.from_file !Opts.jsonf
	)

let () = if !Opts.match_name <> [] then
	Elements_search.print_by_name db !Opts.maxmatch (List.rev !Opts.match_name)