from math import pow
from typing import BinaryIO


def nds_get_info(opt: str, inf: BinaryIO):
    match opt.lower():
        case 'title':
            inf.seek(0x000)
            return inf.read(12).decode()
        case 'gamecode':
            inf.seek(0x00C)
            return inf.read(4).decode()
        case 'makercode':
            inf.seek(0x010)
            return _maker_lookup(inf.read(2).decode())
        case 'unitcode':
            inf.seek(0x012)
            return _unit_lookup(inf.read(1))
        case 'encryptionseed':
            inf.seek(0x013)
            return str(int.from_bytes(inf.read(1), 'little'))
        case 'devicecapacity':
            inf.seek(0x014)
            return _capacity_lookup(int.from_bytes(inf.read(1), 'little'))
        case 'gamerevision':
            inf.seek(0x01C)
            return str(int.from_bytes(inf.read(2), 'little'))
        case 'region':
            inf.seek(0x01D)
            return _region_lookup(int.from_bytes(inf.read(1), 'little'))
        case _:
            return 'Unknown'


def _maker_lookup(code: str) -> str:
    match code:
        case '01':
            return 'Nintendo ({})'.format(code)
        case '41':
            return 'Ubisoft ({})'.format(code)
        case 'FH':
            return 'Foreign Media Games ({})'.format(code)
        case 'GD':
            return 'Square-Enix ({})'.format(code)
        case _:
            return 'Unknown ({})'.format(code)


def _unit_lookup(code: bytes) -> str:
    if code == b'\x00':
        return 'NDS (00h)'
    elif code == b'\x02':
        return 'DSi Enhanced (02h)'
    elif code == b'\x03':
        return 'DSi Exclusive (03h)'
    else:
        return 'Unknown ({})'.format(code)


def _capacity_lookup(code: int) -> str:  # 512Mbit (67108864 bytes) (09h)
    match code:
        case 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12:
            return '{} MB ({})'.format(round(128 * pow(2, code) / 1024), '{}h'.format(str(code).zfill(2)))
        case _:
            return 'Unknown ({})'.format(code)


def _region_lookup(code: int) -> str:
    match code:
        case 0:
            return 'All (0x00 (0))'
        case 64:
            return 'Korea (0x40 (64))'
        case 128:
            return 'China (0x80 (128))'
        case _:
            return 'Unknown ({})'.format(code)