defmodule AshDoubleEntry.ULID do
@moduledoc """
An Ecto type for ULID strings.
"""
use Ash.Type
@typedoc """
A hex-encoded ULID string.
"""
@type t :: <<_::208>>
@doc """
The underlying schema type.
"""
def storage_type, do: :binary
@doc """
Casts a string to ULID.
"""
def cast_input(nil, _), do: {:ok, nil}
def cast_input(<<_::bytes-size(16)>> = value, constraints) do
case encode(value) do
{:ok, encoded} -> cast_input(encoded, constraints)
:error -> :error
end
end
def cast_input(<<_::bytes-size(26)>> = value, _) do
if valid?(value) do
{:ok, value}
else
:error
end
end
def cast_input(_, _), do: :error
@doc """
Converts a Crockford Base32 encoded ULID into a binary.
"""
def dump_to_native(nil, _), do: {:ok, nil}
def dump_to_native(<<_::bytes-size(26)>> = encoded, _), do: decode(encoded)
def dump_to_native(_, _), do: :error
@doc """
Converts a binary ULID into a Crockford Base32 encoded string.
"""
def cast_stored(nil, _), do: {:ok, nil}
def cast_stored(<<_::unsigned-size(128)>> = bytes, _), do: encode(bytes)
def cast_stored(_, _), do: :error
@doc false
def autogenerate, do: generate()
@doc """
Generates a Crockford Base32 encoded ULID.
If a value is provided for `timestamp`, the generated ULID will be for the provided timestamp.
Otherwise, a ULID will be generated for the current time.
Arguments:
* `timestamp`: A Unix timestamp with millisecond precision.
"""
def generate(timestamp \\ System.system_time(:millisecond))
def generate(%DateTime{} = datetime) do
datetime
|> DateTime.to_unix(:millisecond)
|> generate()
end
def generate(timestamp) do
{:ok, ulid} = encode(bingenerate(timestamp))
ulid
end
@doc """
Generates a binary ULID.
If a value is provided for `timestamp`, the generated ULID will be for the provided timestamp.
Otherwise, a ULID will be generated for the current time.
Arguments:
* `timestamp`: A Unix timestamp with millisecond precision.
"""
def bingenerate(timestamp \\ System.system_time(:millisecond)) do
<<timestamp::unsigned-size(48), :crypto.strong_rand_bytes(10)::binary>>
end
@doc false
def encode(
<<b1::3, b2::5, b3::5, b4::5, b5::5, b6::5, b7::5, b8::5, b9::5, b10::5, b11::5, b12::5,
b13::5, b14::5, b15::5, b16::5, b17::5, b18::5, b19::5, b20::5, b21::5, b22::5, b23::5,
b24::5, b25::5, b26::5>>
) do
<<e(b1), e(b2), e(b3), e(b4), e(b5), e(b6), e(b7), e(b8), e(b9), e(b10), e(b11), e(b12),
e(b13), e(b14), e(b15), e(b16), e(b17), e(b18), e(b19), e(b20), e(b21), e(b22), e(b23),
e(b24), e(b25), e(b26)>>
catch
:error -> :error
else
encoded -> {:ok, encoded}
end
def encode(_), do: :error
@compile {:inline, e: 1}
defp e(0), do: ?0
defp e(1), do: ?1
defp e(2), do: ?2
defp e(3), do: ?3
defp e(4), do: ?4
defp e(5), do: ?5
defp e(6), do: ?6
defp e(7), do: ?7
defp e(8), do: ?8
defp e(9), do: ?9
defp e(10), do: ?A
defp e(11), do: ?B
defp e(12), do: ?C
defp e(13), do: ?D
defp e(14), do: ?E
defp e(15), do: ?F
defp e(16), do: ?G
defp e(17), do: ?H
defp e(18), do: ?J
defp e(19), do: ?K
defp e(20), do: ?M
defp e(21), do: ?N
defp e(22), do: ?P
defp e(23), do: ?Q
defp e(24), do: ?R
defp e(25), do: ?S
defp e(26), do: ?T
defp e(27), do: ?V
defp e(28), do: ?W
defp e(29), do: ?X
defp e(30), do: ?Y
defp e(31), do: ?Z
defp decode(
<<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, c8::8, c9::8, c10::8, c11::8, c12::8,
c13::8, c14::8, c15::8, c16::8, c17::8, c18::8, c19::8, c20::8, c21::8, c22::8, c23::8,
c24::8, c25::8, c26::8>>
) do
<<d(c1)::3, d(c2)::5, d(c3)::5, d(c4)::5, d(c5)::5, d(c6)::5, d(c7)::5, d(c8)::5, d(c9)::5,
d(c10)::5, d(c11)::5, d(c12)::5, d(c13)::5, d(c14)::5, d(c15)::5, d(c16)::5, d(c17)::5,
d(c18)::5, d(c19)::5, d(c20)::5, d(c21)::5, d(c22)::5, d(c23)::5, d(c24)::5, d(c25)::5,
d(c26)::5>>
catch
:error -> :error
else
decoded -> {:ok, decoded}
end
defp decode(_), do: :error
@compile {:inline, d: 1}
defp d(?0), do: 0
defp d(?1), do: 1
defp d(?2), do: 2
defp d(?3), do: 3
defp d(?4), do: 4
defp d(?5), do: 5
defp d(?6), do: 6
defp d(?7), do: 7
defp d(?8), do: 8
defp d(?9), do: 9
defp d(?A), do: 10
defp d(?B), do: 11
defp d(?C), do: 12
defp d(?D), do: 13
defp d(?E), do: 14
defp d(?F), do: 15
defp d(?G), do: 16
defp d(?H), do: 17
defp d(?J), do: 18
defp d(?K), do: 19
defp d(?M), do: 20
defp d(?N), do: 21
defp d(?P), do: 22
defp d(?Q), do: 23
defp d(?R), do: 24
defp d(?S), do: 25
defp d(?T), do: 26
defp d(?V), do: 27
defp d(?W), do: 28
defp d(?X), do: 29
defp d(?Y), do: 30
defp d(?Z), do: 31
defp d(_), do: throw(:error)
defp valid?(
<<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, c8::8, c9::8, c10::8, c11::8, c12::8,
c13::8, c14::8, c15::8, c16::8, c17::8, c18::8, c19::8, c20::8, c21::8, c22::8, c23::8,
c24::8, c25::8, c26::8>>
) do
v(c1) && v(c2) && v(c3) && v(c4) && v(c5) && v(c6) && v(c7) && v(c8) && v(c9) && v(c10) &&
v(c11) && v(c12) && v(c13) &&
v(c14) && v(c15) && v(c16) && v(c17) && v(c18) && v(c19) && v(c20) && v(c21) && v(c22) &&
v(c23) && v(c24) && v(c25) && v(c26)
end
defp valid?(_), do: false
@compile {:inline, v: 1}
defp v(?0), do: true
defp v(?1), do: true
defp v(?2), do: true
defp v(?3), do: true
defp v(?4), do: true
defp v(?5), do: true
defp v(?6), do: true
defp v(?7), do: true
defp v(?8), do: true
defp v(?9), do: true
defp v(?A), do: true
defp v(?B), do: true
defp v(?C), do: true
defp v(?D), do: true
defp v(?E), do: true
defp v(?F), do: true
defp v(?G), do: true
defp v(?H), do: true
defp v(?J), do: true
defp v(?K), do: true
defp v(?M), do: true
defp v(?N), do: true
defp v(?P), do: true
defp v(?Q), do: true
defp v(?R), do: true
defp v(?S), do: true
defp v(?T), do: true
defp v(?V), do: true
defp v(?W), do: true
defp v(?X), do: true
defp v(?Y), do: true
defp v(?Z), do: true
defp v(_), do: false
end
