import struct
with open ("DOJDUAL.bin", "rb") as f:
src = bytearray (f.read())
kovsh_tab = [
0xe7, 0x06, 0xa3, 0x70, 0xf2, 0x58, 0xe6, 0x59, 0xe4, 0xcf, 0xc2, 0x79, 0x1d, 0xe3, 0x71, 0x0e,
0xb6, 0x90, 0x9a, 0x2a, 0x8c, 0x41, 0xf7, 0x82, 0x9b, 0xef, 0x99, 0x0c, 0xfa, 0x2f, 0xf1, 0xfe,
0x8f, 0x70, 0xf4, 0xc1, 0xb5, 0x3d, 0x7c, 0x60, 0x4c, 0x09, 0xf4, 0x2e, 0x7c, 0x87, 0x63, 0x5f,
0xce, 0x99, 0x84, 0x95, 0x06, 0x9a, 0x20, 0x23, 0x5a, 0xb9, 0x52, 0x95, 0x48, 0x2c, 0x84, 0x60,
0x69, 0xe3, 0x93, 0x49, 0xb9, 0xd6, 0xbb, 0xd6, 0x9e, 0xdc, 0x96, 0x12, 0xfa, 0x60, 0xda, 0x5f,
0x55, 0x5d, 0x5b, 0x20, 0x07, 0x1e, 0x97, 0x42, 0x77, 0xea, 0x1d, 0xe0, 0x70, 0xfb, 0x6a, 0x00,
0x77, 0x9a, 0xef, 0x1b, 0xe0, 0xf9, 0x0d, 0xc1, 0x2e, 0x2f, 0xef, 0x25, 0x29, 0xe5, 0xd8, 0x2c,
0xaf, 0x01, 0xd9, 0x6c, 0x31, 0xce, 0x5c, 0xea, 0xab, 0x1c, 0x92, 0x16, 0x61, 0xbc, 0xe4, 0x7c,
0x5a, 0x76, 0xe9, 0x92, 0x39, 0x5b, 0x97, 0x60, 0xea, 0x57, 0x83, 0x9c, 0x92, 0x29, 0xa7, 0x12,
0xa9, 0x71, 0x7a, 0xf9, 0x07, 0x68, 0xa7, 0x45, 0x88, 0x10, 0x81, 0x12, 0x2c, 0x67, 0x4d, 0x55,
0x33, 0xf0, 0xfa, 0xd7, 0x1d, 0x4d, 0x0e, 0x63, 0x03, 0x34, 0x65, 0xe2, 0x76, 0x0f, 0x98, 0xa9,
0x5f, 0x9a, 0xd3, 0xca, 0xdd, 0xc1, 0x5b, 0x3d, 0x4d, 0xf8, 0x40, 0x08, 0xdc, 0x05, 0x38, 0x00,
0xcb, 0x24, 0x02, 0xff, 0x39, 0xe2, 0x9e, 0x04, 0x9a, 0x08, 0x63, 0xc8, 0x2b, 0x5a, 0x34, 0x06,
0x62, 0xc1, 0xbb, 0x8a, 0xd0, 0x54, 0x4c, 0x43, 0x21, 0x4e, 0x4c, 0x99, 0x80, 0xc2, 0x3d, 0xce,
0x2a, 0x7b, 0x09, 0x62, 0x1a, 0x91, 0x9b, 0xc3, 0x41, 0x24, 0xa0, 0xfd, 0xb5, 0x67, 0x93, 0x07,
0xa7, 0xb8, 0x85, 0x8a, 0xa1, 0x1e, 0x4f, 0xb6, 0x75, 0x38, 0x65, 0x8a, 0xf9, 0x7c, 0x00, 0xa0,
]
rom_size = len(src)
for i in range(rom_size//2):
x, = struct.unpack_from("<H", src, i * 2)
if ((i & 0x040080) != 0x000080): x ^= 0x0001
if((i & 0x004008) == 0x004008 and (i & 0x180000) != 0x000000): x ^= 0x0002
if ((i & 0x000030) == 0x000010): x ^= 0x0004
if ((i & 0x000242) != 0x000042): x ^= 0x0008
if ((i & 0x008100) == 0x008000): x ^= 0x0010
if ((i & 0x002004) != 0x000004): x ^= 0x0020
if ((i & 0x011800) != 0x010000): x ^= 0x0040
if ((i & 0x000820) == 0x000820): x ^= 0x0080
x ^= kovsh_tab[i & 0xff] << 8
struct.pack_into("<H", src, i * 2, x)
with open("DDPDOJ_P1.bin", "wb") as f:
f.write(src)