#
# Copyright (C) 1993-1996 Id Software, Inc.
# Copyright (C) 2019-2020 Nobuaki Tanaka
# Copyright (C) 2024 Devin Shwagginz
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#

module Doocr
  class DoomRandom
    class_getter table : Array(Int32) = [
      0, 8, 109, 220, 222, 241, 149, 107, 75, 248, 254, 140, 16, 66,
      74, 21, 211, 47, 80, 242, 154, 27, 205, 128, 161, 89, 77, 36,
      95, 110, 85, 48, 212, 140, 211, 249, 22, 79, 200, 50, 28, 188,
      52, 140, 202, 120, 68, 145, 62, 70, 184, 190, 91, 197, 152, 224,
      149, 104, 25, 178, 252, 182, 202, 182, 141, 197, 4, 81, 181, 242,
      145, 42, 39, 227, 156, 198, 225, 193, 219, 93, 122, 175, 249, 0,
      175, 143, 70, 239, 46, 246, 163, 53, 163, 109, 168, 135, 2, 235,
      25, 92, 20, 145, 138, 77, 69, 166, 78, 176, 173, 212, 166, 113,
      94, 161, 41, 50, 239, 49, 111, 164, 70, 60, 2, 37, 171, 75,
      136, 156, 11, 56, 42, 146, 138, 229, 73, 146, 77, 61, 98, 196,
      135, 106, 63, 197, 195, 86, 96, 203, 113, 101, 170, 247, 181, 113,
      80, 250, 108, 7, 255, 237, 129, 226, 79, 107, 112, 166, 103, 241,
      24, 223, 239, 120, 198, 58, 60, 82, 128, 3, 184, 66, 143, 224,
      145, 224, 81, 206, 163, 45, 63, 90, 168, 114, 59, 33, 159, 95,
      28, 139, 123, 98, 125, 196, 15, 70, 194, 253, 54, 14, 109, 226,
      71, 17, 161, 93, 186, 87, 244, 138, 20, 52, 123, 251, 26, 36,
      17, 46, 52, 231, 232, 76, 31, 221, 84, 37, 216, 165, 212, 106,
      197, 242, 98, 43, 39, 175, 254, 145, 190, 84, 118, 222, 187, 136,
      120, 163, 236, 249,
    ]

    @index : Int32

    def initialize
      @index = 0
    end

    def initialize(seed : Int32)
      @index = seed & 0xff
    end

    def next : Int32
      @index = (@index + 1) & 0xff
      return @@table[@index]
    end

    def clear
      @index = 0
    end
  end
end
