from pathlib import Path


def u16(data, off):
    return data[off] | (data[off + 1] << 8)


def u32(data, off):
    return u16(data, off) | (u16(data, off + 2) << 16)


def main():
    path = Path(r"k:\ghidra\Crusader_Decomp\REGRET.EXE")
    data = path.read_bytes()
    ne_off = u32(data, 0x3C)
    seg_table_off = ne_off + u16(data, ne_off + 0x22)
    align_shift = u16(data, ne_off + 0x32)
    seg_count = u16(data, ne_off + 0x1C)

    print(f"NE header: 0x{ne_off:X}")
    print(f"Segment table: 0x{seg_table_off:X}")
    print(f"Align shift: {align_shift}")
    print(f"Segment count: {seg_count}")

    selector = 0x1148
    seg_index = ((selector - 0x1000) // 8) + 1
    seg_entry_off = seg_table_off + (seg_index - 1) * 8
    sector = u16(data, seg_entry_off)
    seg_len = u16(data, seg_entry_off + 2)
    flags = u16(data, seg_entry_off + 4)
    min_alloc = u16(data, seg_entry_off + 6)
    seg_file_off = sector << align_shift

    print(f"Selector 0x{selector:X} -> segment index {seg_index}")
    print(
        f"Segment entry @ 0x{seg_entry_off:X}: sector=0x{sector:X} len=0x{seg_len:X} flags=0x{flags:X} min=0x{min_alloc:X} file=0x{seg_file_off:X}"
    )

    for site in (0x3678, 0x36C0, 0x3702):
        raw = seg_file_off + site
        print(f"Site 0x{site:04X} -> file 0x{raw:X}: {data[raw:raw+8].hex(' ')}")

    reloc_off = seg_file_off + seg_len
    count = u16(data, reloc_off)
    print(f"Reloc table @ 0x{reloc_off:X}, count={count}")

    wanted = {
        0x3678,
        0x3679,
        0x367A,
        0x36C0,
        0x36C1,
        0x36C2,
        0x3702,
        0x3703,
        0x3704,
    }
    hits = []
    pos = reloc_off + 2
    for i in range(count):
        src_type = data[pos]
        flags = data[pos + 1]
        src_off = u16(data, pos + 2)
        payload = data[pos + 4 : pos + 8]
        if src_off in wanted:
            hits.append((i, pos, src_type, flags, src_off, payload))
        pos += 8

    for i, pos, src_type, flags, src_off, payload in hits:
        print(
            f"Hit #{i} rec@0x{pos:X}: src_type=0x{src_type:02X} flags=0x{flags:02X} src=0x{src_off:04X} payload={payload.hex(' ')}"
        )


if __name__ == "__main__":
    main()