rdf-ex/lib/rdf/datatypes/date.ex

56 lines
1.3 KiB
Elixir

defmodule RDF.Date do
@moduledoc """
`RDF.Datatype` for XSD date.
"""
use RDF.Datatype, id: RDF.Datatype.NS.XSD.date
@grammar ~r/\A(-?\d{4}-\d{2}-\d{2})((?:[\+\-]\d{2}:\d{2})|UTC|GMT|Z)?\Z/
def convert(%Date{} = value, %{tz: "+00:00"} = opts) do
{convert(value, Map.delete(opts, :tz)), "Z"}
end
def convert(%Date{} = value, %{tz: tz} = opts) do
{convert(value, Map.delete(opts, :tz)), tz}
end
# Special case for date and dateTime, for which 0 is not a valid year
def convert(%Date{year: 0} = value, opts), do: super(value, opts)
def convert(%Date{} = value, _), do: value
def convert(value, opts) when is_binary(value) do
case Regex.run(@grammar, value) do
[_, date] ->
date
|> do_convert
|> convert(opts)
[_, date, zone] ->
date
|> do_convert
|> convert(Map.put(opts, :tz, zone))
_ ->
super(value, opts)
end
end
def convert(value, opts), do: super(value, opts)
defp do_convert(value) do
case Date.from_iso8601(value) do
{:ok, date} -> date
_ -> nil
end
end
def canonical_lexical(%Date{} = value) do
Date.to_iso8601(value)
end
def canonical_lexical({%Date{} = value, zone}) do
canonical_lexical(value) <> zone
end
end