from typing import Tuple
import logging
from palworld_save_tools.compressor.enums import SaveType, MagicBytes
logger = logging.getLogger(__name__)
class Compressor:
    def __init__(self):
        pass
    def _parse_sav_header(self, sav_data: bytes) -> Tuple[int, int, bytes, int, int]:
        if len(sav_data) < 24:
            raise ValueError('File too small to parse header')
        uncompressed_len = int.from_bytes(sav_data[0:4], byteorder='little')
        compressed_len = int.from_bytes(sav_data[4:8], byteorder='little')
        magic_bytes = sav_data[8:11]
        save_type = sav_data[11]
        data_offset = 12
        if magic_bytes == MagicBytes.CNK.value:
            uncompressed_len = int.from_bytes(sav_data[12:16], byteorder='little')
            compressed_len = int.from_bytes(sav_data[16:20], byteorder='little')
            magic_bytes = sav_data[20:23]
            save_type = sav_data[23]
            data_offset = 24
        if magic_bytes not in (MagicBytes.PLZ.value, MagicBytes.PLM.value, MagicBytes.CNK.value):
            raise ValueError(f'Unknown magic bytes: {magic_bytes!r}')
        return (uncompressed_len, compressed_len, magic_bytes, save_type, data_offset)
    def _get_magic(self, save_type: int) -> bytes | None:
        if save_type == SaveType.PLZ.value:
            return MagicBytes.PLZ.value
        elif save_type == SaveType.PLM.value:
            return MagicBytes.PLM.value
        elif save_type == SaveType.CNK.value:
            return MagicBytes.CNK.value
        return None
    def check_savtype_format(self, save_type: int) -> SaveType | None:
        match save_type:
            case SaveType.PLZ.value:
                return SaveType.PLZ
            case SaveType.PLM.value:
                return SaveType.PLM
            case SaveType.CNK.value:
                return SaveType.CNK
            case _:
                logger.debug(f'Unknown save type: 0x{save_type:02X}')
                return None
    def check_sav_format(self, sav_data: bytes) -> SaveType | None:
        if len(sav_data) < 12:
            return None
        magic = sav_data[8:11]
        logger.debug(f'Checking SAV format,magic bytes: {magic!r}')
        match magic:
            case MagicBytes.PLZ.value:
                return SaveType.PLZ
            case MagicBytes.PLM.value:
                return SaveType.PLM
            case MagicBytes.CNK.value:
                return SaveType.CNK
            case _:
                logger.debug(f'Unknown magic bytes: {magic!r}')
                return None
    def build_sav(self, compressed_data: bytes, uncompressed_len: int, compressed_len: int, magic_bytes: bytes, save_type: int) -> bytes:
        logger.debug('Building.sav file...')
        result = bytearray()
        result.extend(uncompressed_len.to_bytes(4, 'little'))
        result.extend(compressed_len.to_bytes(4, 'little'))
        result.extend(magic_bytes)
        result.extend(bytes([save_type]))
        result.extend(compressed_data)
        logger.debug('Finished building.sav file.')
        return bytes(result)