#!/usr/bin/python -u
#
# p7zr library
#
# Copyright (c) 2019-2021 Hiroshi Miura <miurahr@linux.com>
# Copyright (c) 2004-2015 by Joachim Bauch, mail@joachim-bauch.de
# 7-Zip Copyright (C) 1999-2010 Igor Pavlov
# LZMA SDK Copyright (C) 1999-2010 Igor Pavlov
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
import bz2
import lzma
import struct
import zlib
from abc import ABC, abstractmethod
from enum import Enum
from typing import Any, Dict, List, Optional, Tuple, Union

import bcj  # type: ignore  # noqa
import pyppmd
import pyzstd
from Cryptodome.Cipher import AES
from Cryptodome.Random import get_random_bytes

from py7zr.exceptions import PasswordRequired, UnsupportedCompressionMethodError
from py7zr.helpers import Buffer, calculate_crc32, calculate_key
from py7zr.properties import (
    COMPRESSION_METHOD,
    FILTER_ARM,
    FILTER_ARMTHUMB,
    FILTER_BROTLI,
    FILTER_BZIP2,
    FILTER_COPY,
    FILTER_CRYPTO_AES256_SHA256,
    FILTER_DEFLATE,
    FILTER_DEFLATE64,
    FILTER_DELTA,
    FILTER_IA64,
    FILTER_LZMA,
    FILTER_LZMA2,
    FILTER_POWERPC,
    FILTER_PPMD,
    FILTER_SPARC,
    FILTER_X86,
    FILTER_ZSTD,
    MAGIC_7Z,
    CompressionMethod,
    get_default_blocksize,
)

try:
    import brotli  # type: ignore  # noqa
except ImportError:
    import brotlicffi as brotli  # type: ignore  # noqa
try:
    import inflate64  # noqa
except ImportError:
    inflate64 = None  # type: ignore  # noqa
brotli_major = 1
brotli_minor = 0


class ISevenZipCompressor(ABC):
    @abstractmethod
    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        """
        Compress data (interface)
        :param data: input data
        :return: output data
        """
        pass

    @abstractmethod
    def flush(self) -> bytes:
        """
        Flush output buffer(interface)
        :return: output data
        """
        pass


class ISevenZipDecompressor(ABC):
    @abstractmethod
    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        """
        Decompress data (interface)
        :param data: input data
        :param max_length: maximum length of output data when it can respect, otherwise ignore.
        :return: output data
        """
        pass


class AESCompressor(ISevenZipCompressor):
    """AES Compression(Encryption) class.
    It accept pre-processing filter which may be a LZMA compression."""

    AES_CBC_BLOCKSIZE = 16

    def __init__(self, password: str, blocksize: Optional[int] = None) -> None:
        self.cycles = 19  # as same as p7zip
        self.iv = get_random_bytes(16)
        self.salt = b""
        self.method = CompressionMethod.CRYPT_AES256_SHA256
        key = calculate_key(password.encode("utf-16LE"), self.cycles, self.salt, "sha256")
        self.iv += bytes(self.AES_CBC_BLOCKSIZE - len(self.iv))  # zero padding if iv < AES_CBC_BLOCKSIZE
        self.cipher = AES.new(key, AES.MODE_CBC, self.iv)
        self.flushed = False
        if blocksize:
            self.buf = Buffer(size=blocksize + self.AES_CBC_BLOCKSIZE * 2)
        else:
            self.buf = Buffer(size=get_default_blocksize() + self.AES_CBC_BLOCKSIZE * 2)

    def encode_filter_properties(self):
        saltsize = len(self.salt)
        ivsize = len(self.iv)
        ivfirst = 1  # it should always 1
        saltfirst = 1 if len(self.salt) > 0 else 0
        firstbyte = (self.cycles + (ivfirst << 6) + (saltfirst << 7)).to_bytes(1, "little")
        secondbyte = (((ivsize - 1) & 0x0F) + (((saltsize - saltfirst) << 4) & 0xF0)).to_bytes(1, "little")
        properties = firstbyte + secondbyte + self.salt + self.iv
        return properties

    def compress(self, data):
        """Compression + AES encryption with 16byte alignment."""
        # The size is < 16 which should be only last chunk.
        # From p7zip/CPP/7zip/common/FilterCoder.cpp
        # /*
        # AES filters need 16-bytes alignment for HARDWARE-AES instructions.
        # So we call IFilter::Filter(, size), where (size != 16 * N) only for last data block.
        # AES-CBC filters need data size aligned for 16-bytes.
        # So the encoder can add zeros to the end of original stream.
        # Some filters (BCJ and others) don't process data at the end of stream in some cases.
        # So the encoder and decoder write such last bytes without change.
        # */
        currentlen = len(self.buf) + len(data)
        # hopefully aligned and larger than block size.
        if currentlen >= 16 and (currentlen & 0x0F) == 0:
            self.buf.add(data)
            res = self.cipher.encrypt(self.buf.view)
            self.buf.reset()
        elif currentlen > 16:  # when not aligned
            # nextpos = (currentlen // self.AES_CBC_BLOCKSIZE) * self.AES_CBC_BLOCKSIZE
            nextpos = currentlen & ~0x0F
            buflen = len(self.buf)
            self.buf.add(data[: nextpos - buflen])
            res = self.cipher.encrypt(self.buf.view)
            self.buf.set(data[nextpos - buflen :])
        else:  # pragma: no-cover # smaller than block size, it will processed when flush()
            self.buf.add(data)
            res = b""
        return res

    def flush(self):
        if len(self.buf) > 0:
            # padlen = 16 - currentlen % 16 if currentlen % 16 > 0 else 0
            padlen = -len(self.buf) & 15
            self.buf.add(bytes(padlen))
            res = self.cipher.encrypt(self.buf.view)
            self.buf.reset()
        else:
            res = b""
        return res


class AESDecompressor(ISevenZipDecompressor):
    """Decrypt data"""

    def __init__(self, aes_properties: bytes, password: str, blocksize: Optional[int] = None) -> None:
        firstbyte = aes_properties[0]
        numcyclespower = firstbyte & 0x3F
        if firstbyte & 0xC0 != 0:
            saltsize = (firstbyte >> 7) & 1
            ivsize = (firstbyte >> 6) & 1
            secondbyte = aes_properties[1]
            saltsize += secondbyte >> 4
            ivsize += secondbyte & 0x0F
            assert len(aes_properties) == 2 + saltsize + ivsize
            salt = aes_properties[2 : 2 + saltsize]
            iv = aes_properties[2 + saltsize : 2 + saltsize + ivsize]
            assert len(salt) == saltsize
            assert len(iv) == ivsize
            assert numcyclespower <= 24
            if ivsize < 16:
                iv += bytes("\x00" * (16 - ivsize), "ascii")
            key = calculate_key(password.encode("utf-16LE"), numcyclespower, salt, "sha256")
            self.cipher = AES.new(key, AES.MODE_CBC, iv)
            if blocksize:
                self.buf = Buffer(size=blocksize + 16)
            else:
                self.buf = Buffer(size=get_default_blocksize() + 16)
        else:
            raise UnsupportedCompressionMethodError(firstbyte, "Wrong 7zAES properties")

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        currentlen = len(self.buf) + len(data)
        # when aligned to 16 bytes(expected)
        if len(data) > 0 and (currentlen & 0x0F) == 0:
            self.buf.add(data)
            temp = self.cipher.decrypt(self.buf.view)
            self.buf.reset()
            return temp
        elif len(data) > 0:  # pragma: no-cover
            # nextpos = (currentlen // 16) * 16
            nextpos = currentlen & ~0x0F
            buflen = len(self.buf)
            temp2 = data[nextpos - buflen :]
            self.buf.add(data[: nextpos - buflen])
            temp = self.cipher.decrypt(self.buf.view)
            self.buf.set(temp2)
            return temp
        elif len(self.buf) == 0:  # pragma: no-cover  # action flush
            return b""
        else:  # pragma: no-cover  # action padding
            # align = 16
            # padlen = (align - offset % align) % align
            #       = (align - (offset & (align - 1))) & (align - 1)
            #       = -offset & (align -1)
            #       = -offset & (16 - 1) = -offset & 15
            padlen = -len(self.buf) & 15
            self.buf.add(bytes(padlen))
            temp3 = self.cipher.decrypt(self.buf.view)  # type: bytes
            self.buf.reset()
            return temp3


class DeflateCompressor(ISevenZipCompressor):
    def __init__(self):
        self._compressor = zlib.compressobj(wbits=-15)

    def compress(self, data):
        return self._compressor.compress(data)

    def flush(self):
        return self._compressor.flush()


class DeflateDecompressor(ISevenZipDecompressor):
    def __init__(self):
        self.flushed = False
        self._decompressor = zlib.decompressobj(wbits=-15)

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        if len(data) == 0:
            if self.flushed:
                return b""
            else:
                self.flushed = True
                return self._decompressor.flush()
        return self._decompressor.decompress(data)


class Deflate64Compressor(ISevenZipCompressor):
    def __init__(self):
        raise RuntimeError("Deflate64 compression not implemented yet")


class Deflate64Decompressor(ISevenZipDecompressor):
    def __init__(self):
        self.flushed = False
        if inflate64 is not None:
            self._decompressor = inflate64.Inflater()
            self._enabled = True
        else:
            self._enabled = False

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        if not self._enabled:
            raise UnsupportedCompressionMethodError(None, "inflate64 is not installed.")
        if len(data) == 0:
            if self.flushed:
                return b""
            else:
                self.flushed = True
                return self._decompressor.inflate(b"")
        return self._decompressor.inflate(data)


class CopyCompressor(ISevenZipCompressor):
    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return bytes(data)

    def flush(self):
        return b""


class CopyDecompressor(ISevenZipDecompressor):
    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return bytes(data)


class PpmdDecompressor(ISevenZipDecompressor):
    """Decompress PPMd compressed data"""

    def __init__(self, properties: bytes, blocksize: Optional[int] = None):
        if not isinstance(properties, bytes):
            raise UnsupportedCompressionMethodError(properties, "Unknown type of properties is passed")
        if len(properties) == 5:
            order, mem = struct.unpack("<BL", properties)
        elif len(properties) == 7:
            order, mem, _, _ = struct.unpack("<BLBB", properties)
        else:
            raise UnsupportedCompressionMethodError(properties, "Unknown size of properties is passed")
        self.decoder = pyppmd.Ppmd7Decoder(order, mem)

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length=-1) -> bytes:
        if len(data) == 0 and self.decoder.needs_input:
            return self.decoder.decode(b"\0", max_length)
        return self.decoder.decode(data, max_length)


class PpmdCompressor(ISevenZipCompressor):
    """Compress with PPMd compression algorithm"""

    def __init__(self, properties: bytes):
        order, mem = self._decode_property(properties)
        self.encoder = pyppmd.Ppmd7Encoder(order, mem)

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self.encoder.encode(data)

    def flush(self):
        return self.encoder.flush()

    def _decode_property(self, properties):
        order, mem, _, _ = struct.unpack("<BLBB", properties)
        return order, mem

    @classmethod
    def encode_filter_properties(cls, filter: Dict[str, Union[str, int]]):
        order = filter.get("order", 8)
        mem = filter.get("mem", 24)
        if isinstance(mem, str):
            if mem.isdecimal():
                size = 1 << int(mem)
            elif mem.lower().endswith("m") and mem[:-1].isdecimal():
                size = int(mem[:-1]) << 20
            elif mem.lower().endswith("k") and mem[:-1].isdecimal():
                size = int(mem[:-1]) << 10
            elif mem.lower().endswith("b") and mem[:-1].isdecimal():
                size = int(mem[:-1])
            else:
                raise ValueError("Ppmd:Unsupported memory size is specified: {0}".format(mem))
        elif isinstance(mem, int):
            size = 1 << mem
        else:
            raise ValueError("Ppmd:Unsupported memory size is specified: {0}".format(mem))
        properties = struct.pack("<BLBB", order, size, 0, 0)
        return properties


class BcjSparcDecoder(ISevenZipDecompressor):
    def __init__(self, size: int):
        self.decoder = bcj.SparcDecoder(size)

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return self.decoder.decode(data)


class BcjSparcEncoder(ISevenZipCompressor):
    def __init__(self):
        self.encoder = bcj.SparcEncoder()

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self.encoder.encode(data)

    def flush(self):
        return self.encoder.flush()


class BcjPpcDecoder(ISevenZipDecompressor):
    def __init__(self, size: int):
        self.decoder = bcj.PPCDecoder(size)

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return self.decoder.decode(data)


class BcjPpcEncoder(ISevenZipCompressor):
    def __init__(self):
        self.encoder = bcj.PPCEncoder()

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self.encoder.encode(data)

    def flush(self):
        return self.encoder.flush()


class BcjArmtDecoder(ISevenZipDecompressor):
    def __init__(self, size: int):
        self.decoder = bcj.ARMTDecoder(size)

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return self.decoder.decode(data)


class BcjArmtEncoder(ISevenZipCompressor):
    def __init__(self):
        self.encoder = bcj.ARMTEncoder()

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self.encoder.encode(data)

    def flush(self):
        return self.encoder.flush()


class BcjArmDecoder(ISevenZipDecompressor):
    def __init__(self, size: int):
        self.decoder = bcj.ARMDecoder(size)

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return self.decoder.decode(data)


class BcjArmEncoder(ISevenZipCompressor):
    def __init__(self):
        self.encoder = bcj.ARMEncoder()

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self.encoder.encode(data)

    def flush(self):
        return self.encoder.flush()


class BCJDecoder(ISevenZipDecompressor):
    def __init__(self, size: int):
        self.decoder = bcj.BCJDecoder(size)

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return self.decoder.decode(data)


class BCJEncoder(ISevenZipCompressor):
    def __init__(self):
        self.encoder = bcj.BCJEncoder()

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self.encoder.encode(data)

    def flush(self):
        return self.encoder.flush()


class BrotliCompressor(ISevenZipCompressor):
    def __init__(self, level):
        self._compressor = brotli.Compressor(quality=level)

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self._compressor.process(data)

    def flush(self) -> bytes:
        return self._compressor.flush()


class BrotliDecompressor(ISevenZipDecompressor):
    def __init__(self, properties: bytes, block_size: int):
        if len(properties) != 3:
            raise UnsupportedCompressionMethodError(properties, "Unknown size of properties are passed")
        if (properties[0], properties[1]) > (brotli_major, brotli_minor):
            raise UnsupportedCompressionMethodError(
                properties,
                "Unsupported brotli version: {}.{} our {}.{}".format(
                    properties[0], properties[1], brotli_major, brotli_minor
                ),
            )
        self._prefix_checked = False
        self._decompressor = brotli.Decompressor()

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1):
        if not self._prefix_checked:
            # check first 4bytes
            if data[:4] == b"\x50\x2a\x4d\x18":
                raise UnsupportedCompressionMethodError(
                    data[:4], "Unauthorized and modified Brotli data (skipable frame) found."
                )
            self._prefix_checked = True
        return self._decompressor.process(data)


class ZstdCompressor(ISevenZipCompressor):
    def __init__(self, level: int):
        self.compressor = pyzstd.ZstdCompressor(level)

    def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
        return self.compressor.compress(data)

    def flush(self) -> bytes:
        return self.compressor.flush()


class ZstdDecompressor(ISevenZipDecompressor):
    def __init__(self, properties: bytes, blocksize: int):
        if len(properties) not in [3, 5]:
            raise UnsupportedCompressionMethodError(properties, "Zstd takes 3 or 5 bytes properties.")
        if (properties[0], properties[1], 0) > pyzstd.zstd_version_info:
            raise UnsupportedCompressionMethodError(properties, "Zstd version of archive is higher than us.")
        self.decompressor = pyzstd.ZstdDecompressor()

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return self.decompressor.decompress(data)


algorithm_class_map = {
    FILTER_ZSTD: (ZstdCompressor, ZstdDecompressor),
    FILTER_BROTLI: (BrotliCompressor, BrotliDecompressor),
    FILTER_PPMD: (PpmdCompressor, PpmdDecompressor),
    FILTER_BZIP2: (bz2.BZ2Compressor, bz2.BZ2Decompressor),
    FILTER_COPY: (CopyCompressor, CopyDecompressor),
    FILTER_DEFLATE: (DeflateCompressor, DeflateDecompressor),
    FILTER_DEFLATE64: (Deflate64Compressor, Deflate64Decompressor),
    FILTER_CRYPTO_AES256_SHA256: (AESCompressor, AESDecompressor),
    FILTER_X86: (BCJEncoder, BCJDecoder),
    FILTER_ARM: (BcjArmEncoder, BcjArmDecoder),
    FILTER_ARMTHUMB: (BcjArmtEncoder, BcjArmtDecoder),
    FILTER_POWERPC: (BcjPpcEncoder, BcjPpcDecoder),
    FILTER_SPARC: (BcjSparcEncoder, BcjSparcDecoder),
}  # type: Dict[int, Tuple[Any, Any]]


class LZMA1Decompressor(ISevenZipDecompressor):
    def __init__(self, filters, unpacksize):
        self._decompressor = lzma.LZMADecompressor(format=lzma.FORMAT_RAW, filters=filters)
        self.unpacksize = unpacksize

    def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
        return self._decompressor.decompress(data, max_length)


class SevenZipDecompressor:
    """Main decompressor object which is properly configured and bind to each 7zip folder.
    because 7zip folder can have a custom compression method"""

    def __init__(
        self,
        coders: List[Dict[str, Any]],
        packsize: int,
        unpacksizes: List[int],
        crc: Optional[int],
        password: Optional[str] = None,
        blocksize: Optional[int] = None,
    ) -> None:
        self.input_size = packsize
        self.unpacksizes = unpacksizes
        self.consumed: int = 0
        self.crc = crc
        self.digest: int = 0
        if blocksize:
            self.block_size: int = blocksize
        else:
            self.block_size = get_default_blocksize()
        if len(coders) > 4:
            raise UnsupportedCompressionMethodError(
                coders, "Maximum cascade of filters is 4 but got {}.".format(len(coders))
            )
        self.methods_map = [SupportedMethods.is_native_coder(coder) for coder in coders]  # type: List[bool]
        # Check if password given for encrypted archive
        if SupportedMethods.needs_password(coders) and password is None:
            raise PasswordRequired(coders, "Password is required for extracting given archive.")
        # Check filters combination and required parameters
        if len(coders) >= 2:
            target_compressor = False
            has_bcj = False
            bcj_index = -1
            for i, coder in enumerate(coders):
                filter_id = SupportedMethods.get_filter_id(coder)
                if SupportedMethods.is_compressor_id(filter_id) and filter_id != FILTER_LZMA2:
                    target_compressor = True
                if filter_id in [
                    FILTER_X86,
                    FILTER_ARM,
                    FILTER_ARMTHUMB,
                    FILTER_POWERPC,
                    FILTER_SPARC,
                ]:
                    has_bcj = True
                    bcj_index = i
                # hack for LZMA1+BCJ which should be native+alternative
                if target_compressor and has_bcj:
                    self.methods_map[bcj_index] = False
                    break
        self.chain = []  # type: List[Union[bz2.BZ2Decompressor, lzma.LZMADecompressor, ISevenZipDecompressor]]
        self._unpacksizes = []  # type: List[int]
        self.input_size = self.input_size
        shift = 0
        prev = False
        for i, r in enumerate(self.methods_map):
            shift += 1 if r and prev else 0
            prev = r
            self._unpacksizes.append(unpacksizes[i - shift])
        self._unpacked = [0 for _ in range(len(self._unpacksizes))]
        self.consumed = 0
        self._unused = bytearray()
        self._buf = bytearray()
        self._pos = 0
        # ---
        if all(self.methods_map):
            decompressor = self._get_lzma_decompressor(coders, unpacksizes[-1])
            self.chain.append(decompressor)
        elif not any(self.methods_map):
            for i in range(len(coders)):
                self.chain.append(self._get_alternative_decompressor(coders[i], unpacksizes[i], password))
        elif any(self.methods_map):
            for i in range(len(coders)):
                if (not any(self.methods_map[:i])) and all(self.methods_map[i:]):
                    for j in range(i):
                        self.chain.append(self._get_alternative_decompressor(coders[j], unpacksizes[j], password))
                    self.chain.append(self._get_lzma_decompressor(coders[i:], unpacksizes[i]))
                    break
            else:
                for i in range(len(coders)):
                    if self.methods_map[i]:
                        self.chain.append(self._get_lzma_decompressor([coders[i]], unpacksizes[i]))
                    else:
                        self.chain.append(self._get_alternative_decompressor(coders[i], unpacksizes[i], password))
        else:
            raise UnsupportedCompressionMethodError(coders, "Combination order of methods is not supported.")

    def _decompress(self, data, max_length: int):
        for i, decompressor in enumerate(self.chain):
            if self._unpacked[i] < self._unpacksizes[i]:
                data = decompressor.decompress(data, max_length)
                self._unpacked[i] += len(data)
            elif len(data) == 0:
                data = b""
            else:
                raise EOFError
        return data

    def _read_data(self, fp):
        # read data from disk
        # determine read siize
        #    rest_size: rest size of packed data
        #    unused_s: unused packed data size
        #  size to consume for target file is smaller one from
        #    rest_size - unused_s
        #    block_size - unused_s
        rest_size = self.input_size - self.consumed
        unused_s = len(self._unused)
        read_size = min(rest_size - unused_s, self.block_size - unused_s)
        if read_size > 0:
            data = fp.read(read_size)
            self.consumed += len(data)
        else:
            data = b""
        return data

    def decompress(self, fp, max_length: int = -1) -> bytes:
        if max_length < 0:
            data = self._read_data(fp)
            res = self._buf[self._pos :] + self._decompress(self._unused + data, max_length)
            self._buf = bytearray()
            self._unused = bytearray()
            self._pos = 0
        else:
            current_buf_len = len(self._buf) - self._pos
            if current_buf_len >= max_length:  # we already have enough data
                res = self._buf[self._pos : self._pos + max_length]
                self._pos += max_length
            else:
                data = self._read_data(fp)
                if len(self._unused) > 0:
                    tmp = self._decompress(self._unused + data, max_length)
                    self._unused = bytearray()
                else:
                    tmp = self._decompress(data, max_length)
                if current_buf_len + len(tmp) <= max_length:
                    res = self._buf[self._pos :] + tmp
                    self._buf = bytearray()
                    self._pos = 0
                else:
                    res = self._buf[self._pos :] + tmp[: max_length - current_buf_len]
                    self._buf = bytearray(tmp[max_length - current_buf_len :])
                    self._pos = 0
        self.digest = calculate_crc32(res, self.digest)
        return res

    def check_crc(self):
        return self.crc == self.digest

    @property
    def unused_size(self):
        return len(self._unused)

    def _get_lzma_decompressor(self, coders: List[Dict[str, Any]], unpacksize: int):
        filters: List[Dict[str, Any]] = []
        lzma1 = False
        for coder in coders:
            if coder["numinstreams"] != 1 or coder["numoutstreams"] != 1:
                raise UnsupportedCompressionMethodError(coders, "Only a simple compression method is currently supported.")
            if not SupportedMethods.is_native_coder(coder):
                raise UnsupportedCompressionMethodError(coders, "Non python native method is requested.")
            properties = coder.get("properties", None)
            filter_id = SupportedMethods.get_filter_id(coder)
            if filter_id == FILTER_LZMA:
                lzma1 = True
            if properties is not None:
                filters[:0] = [lzma._decode_filter_properties(filter_id, properties)]  # type: ignore
            else:
                filters[:0] = [{"id": filter_id}]
        if lzma1:
            return LZMA1Decompressor(filters, unpacksize)
        else:
            return lzma.LZMADecompressor(format=lzma.FORMAT_RAW, filters=filters)

    def _get_alternative_decompressor(
        self, coder: Dict[str, Any], unpacksize=None, password=None
    ) -> Union[bz2.BZ2Decompressor, lzma.LZMADecompressor, ISevenZipDecompressor]:  # noqa
        filter_id = SupportedMethods.get_filter_id(coder)
        # Special treatment for BCJ filters
        if filter_id in [
            FILTER_X86,
            FILTER_ARM,
            FILTER_ARMTHUMB,
            FILTER_POWERPC,
            FILTER_SPARC,
        ]:
            return algorithm_class_map[filter_id][1](size=unpacksize)
        # Check supported?
        if SupportedMethods.is_native_coder(coder):
            raise UnsupportedCompressionMethodError(coder, "Unknown method code:{}".format(coder["method"]))
        if filter_id not in algorithm_class_map:
            raise UnsupportedCompressionMethodError(coder, "Unknown method filter_id:{}".format(filter_id))
        if algorithm_class_map[filter_id][1] is None:
            raise UnsupportedCompressionMethodError(
                coder, "Decompression is not supported by {}.".format(SupportedMethods.get_method_name_id(filter_id))
            )
        #
        if SupportedMethods.is_crypto_id(filter_id):
            return algorithm_class_map[filter_id][1](coder["properties"], password, self.block_size)
        elif SupportedMethods.need_property(filter_id):
            return algorithm_class_map[filter_id][1](coder["properties"], self.block_size)
        else:
            return algorithm_class_map[filter_id][1]()


class SevenZipCompressor:
    """Main compressor object to configured for each 7zip folder."""

    __slots__ = [
        "filters",
        "chain",
        "compressor",
        "coders",
        "methods_map",
        "digest",
        "packsize",
        "_block_size",
        "_unpacksizes",
    ]

    def __init__(self, filters=None, password=None, blocksize: Optional[int] = None):
        self.filters: List[Dict[str, Any]] = []
        self.chain: List[ISevenZipCompressor] = []
        self.digest = 0
        self.packsize = 0
        self._unpacksizes: List[int] = []
        if blocksize:
            self._block_size = blocksize
        else:
            self._block_size = get_default_blocksize()
        if filters is None:
            self.filters = [{"id": lzma.FILTER_LZMA2, "preset": 7 | lzma.PRESET_EXTREME}]
        else:
            self.filters = filters
        if len(self.filters) > 4:
            raise UnsupportedCompressionMethodError(
                filters, "Maximum cascade of filters is 4 but got {}.".format(len(self.filters))
            )
        self.methods_map = [SupportedMethods.is_native_filter(filter) for filter in self.filters]
        self.coders: List[Dict[str, Any]] = []
        if all(self.methods_map) and SupportedMethods.is_compressor(self.filters[-1]):  # all native
            self._set_native_compressors_coders(self.filters)
            return
        #
        has_lzma2 = False
        for f in self.filters:
            if f["id"] == FILTER_LZMA2:
                has_lzma2 = True
                break
        if not has_lzma2:
            # when specified other than lzma2, BCJ filters should be alternative
            for i, f in enumerate(self.filters):
                if (
                    f["id"] == FILTER_X86
                    or f["id"] == FILTER_ARM
                    or f["id"] == FILTER_ARMTHUMB
                    or f["id"] == FILTER_SPARC
                    or f["id"] == FILTER_POWERPC
                ):
                    self.methods_map[i] = False
        #
        if not any(self.methods_map):  # all alternative
            for f in filters:
                self._set_alternate_compressors_coders(f, password)
        elif SupportedMethods.is_crypto_id(self.filters[-1]["id"]) and all(self.methods_map[:-1]):
            self._set_native_compressors_coders(self.filters[:-1])
            self._set_alternate_compressors_coders(self.filters[-1], password)
        else:
            raise UnsupportedCompressionMethodError(filters, "Unknown combination of methods.")

    def _set_native_compressors_coders(self, filters):
        self.chain.append(lzma.LZMACompressor(format=lzma.FORMAT_RAW, filters=filters))
        self._unpacksizes.append(0)
        for filter in filters:
            self.coders.insert(0, SupportedMethods.get_coder(filter))

    def _set_alternate_compressors_coders(self, alt_filter, password=None):
        filter_id = alt_filter["id"]
        properties = None
        if filter_id not in algorithm_class_map:
            raise UnsupportedCompressionMethodError(filter_id, "Unknown filter_id is given.")
        elif SupportedMethods.is_crypto_id(filter_id):
            compressor = algorithm_class_map[filter_id][0](password)
        elif SupportedMethods.need_property(filter_id):
            if filter_id == FILTER_ZSTD:
                level = alt_filter.get("level", 3)
                properties = struct.pack("BBBBB", pyzstd.zstd_version_info[0], pyzstd.zstd_version_info[1], level, 0, 0)
                compressor = algorithm_class_map[filter_id][0](level=level)
            elif filter_id == FILTER_PPMD:
                properties = PpmdCompressor.encode_filter_properties(alt_filter)
                compressor = algorithm_class_map[filter_id][0](properties)
            elif filter_id == FILTER_BROTLI:
                level = alt_filter.get("level", 11)
                properties = struct.pack("BBB", brotli_major, brotli_minor, level)
                compressor = algorithm_class_map[filter_id][0](level)
        else:
            compressor = algorithm_class_map[filter_id][0]()
        if SupportedMethods.is_crypto_id(filter_id):
            properties = compressor.encode_filter_properties()
        self.chain.append(compressor)
        self._unpacksizes.append(0)
        self.coders.insert(
            0,
            {
                "method": SupportedMethods.get_method_id(filter_id),
                "properties": properties,
                "numinstreams": 1,
                "numoutstreams": 1,
            },
        )

    def compress(self, fd, fp, crc=0):
        data = fd.read(self._block_size)
        insize = len(data)
        foutsize = 0
        while data:
            crc = calculate_crc32(data, crc)
            for i, compressor in enumerate(self.chain):
                self._unpacksizes[i] += len(data)
                data = compressor.compress(data)
            self.packsize += len(data)
            self.digest = calculate_crc32(data, self.digest)
            foutsize += len(data)
            fp.write(data)
            data = fd.read(self._block_size)
            insize += len(data)
        return insize, foutsize, crc

    def flush(self, fp):
        data = None
        for i, compressor in enumerate(self.chain):
            if data:
                self._unpacksizes[i] += len(data)
                data = compressor.compress(data)
                data += compressor.flush()
            else:
                data = compressor.flush()
        self.packsize += len(data)
        self.digest = calculate_crc32(data, self.digest)
        fp.write(data)
        return len(data)

    @property
    def unpacksizes(self):
        result = []
        shift = 0
        prev = False
        for i, r in enumerate(self.methods_map):
            shift += 1 if r and prev else 0
            prev = r
            result.insert(0, self._unpacksizes[i - shift])
        return result


class MethodsType(Enum):
    compressor = 0
    filter = 1
    crypto = 2


class SupportedMethods:
    """Hold list of methods."""

    formats = [{"name": "7z", "magic": MAGIC_7Z}]
    methods = [
        {
            "id": COMPRESSION_METHOD.COPY,
            "name": "COPY",
            "native": False,
            "need_prop": False,
            "filter_id": FILTER_COPY,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.LZMA2,
            "name": "LZMA2",
            "native": True,
            "need_prop": True,
            "filter_id": FILTER_LZMA2,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.DELTA,
            "name": "DELTA",
            "native": True,
            "need_prop": True,
            "filter_id": FILTER_DELTA,
            "type": MethodsType.filter,
        },
        {
            "id": COMPRESSION_METHOD.LZMA,
            "name": "LZMA",
            "native": True,
            "need_prop": True,
            "filter_id": FILTER_LZMA,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.P7Z_BCJ,
            "name": "BCJ",
            "native": True,
            "need_prop": False,
            "filter_id": FILTER_X86,
            "type": MethodsType.filter,
        },
        {
            "id": COMPRESSION_METHOD.BCJ_PPC,
            "name": "PPC",
            "native": True,
            "need_prop": False,
            "filter_id": FILTER_POWERPC,
            "type": MethodsType.filter,
        },
        {
            "id": COMPRESSION_METHOD.BCJ_IA64,
            "name": "IA64",
            "native": True,
            "need_prop": False,
            "filter_id": FILTER_IA64,
            "type": MethodsType.filter,
        },
        {
            "id": COMPRESSION_METHOD.BCJ_ARM,
            "name": "ARM",
            "native": True,
            "need_prop": False,
            "filter_id": FILTER_ARM,
            "type": MethodsType.filter,
        },
        {
            "id": COMPRESSION_METHOD.BCJ_ARMT,
            "name": "ARMT",
            "native": True,
            "need_prop": False,
            "filter_id": FILTER_ARMTHUMB,
            "type": MethodsType.filter,
        },
        {
            "id": COMPRESSION_METHOD.BCJ_SPARC,
            "name": "SPARC",
            "native": True,
            "need_prop": False,
            "filter_id": FILTER_SPARC,
            "type": MethodsType.filter,
        },
        {
            "id": COMPRESSION_METHOD.MISC_DEFLATE,
            "name": "DEFLATE",
            "native": False,
            "need_prop": False,
            "filter_id": FILTER_DEFLATE,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.MISC_BZIP2,
            "name": "BZip2",
            "native": False,
            "need_prop": False,
            "filter_id": FILTER_BZIP2,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.MISC_ZSTD,
            "name": "ZStandard",
            "native": False,
            "need_prop": True,
            "filter_id": FILTER_ZSTD,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.PPMD,
            "name": "PPMd",
            "native": False,
            "need_prop": True,
            "filter_id": FILTER_PPMD,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.MISC_BROTLI,
            "name": "Brotli",
            "native": False,
            "need_prop": True,
            "filter_id": FILTER_BROTLI,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.MISC_DEFLATE64,
            "name": "DEFLATE64",
            "native": False,
            "need_prop": False,
            "filter_id": FILTER_DEFLATE64,
            "type": MethodsType.compressor,
        },
        {
            "id": COMPRESSION_METHOD.CRYPT_AES256_SHA256,
            "name": "7zAES",
            "native": False,
            "need_prop": True,
            "filter_id": FILTER_CRYPTO_AES256_SHA256,
            "type": MethodsType.crypto,
        },
    ]

    @classmethod
    def _find_method(cls, key_id, key_value):
        return next((item for item in cls.methods if item[key_id] == key_value), None)

    @classmethod
    def get_method_name_id(cls, filter_id):
        method = cls._find_method("filter_id", filter_id)
        return method["name"]

    @classmethod
    def get_filter_id(cls, coder):
        method = cls._find_method("id", coder["method"])
        if method is None:
            return None
        return method["filter_id"]

    @classmethod
    def is_native_filter(cls, filter) -> bool:
        method = cls._find_method("filter_id", filter["id"])
        if method is None:
            raise UnsupportedCompressionMethodError(filter["id"], "Unknown method id is given.")
        return method["native"]

    @classmethod
    def is_compressor(cls, filter):
        method = cls._find_method("filter_id", filter["id"])
        return method["type"] == MethodsType.compressor

    @classmethod
    def is_compressor_id(cls, filter_id):
        method = cls._find_method("filter_id", filter_id)
        return method["type"] == MethodsType.compressor

    @classmethod
    def is_native_coder(cls, coder) -> bool:
        method = cls._find_method("id", coder["method"])
        if method is None:
            cls.raise_unsupported_method_id(coder)
        return method["native"]

    @classmethod
    def need_property(cls, filter_id):
        method = cls._find_method("filter_id", filter_id)
        if method is None:
            raise UnsupportedCompressionMethodError(filter_id, "Found an sunpported filter id.")
        return method["need_prop"]

    @classmethod
    def is_crypto_id(cls, filter_id) -> bool:
        method = cls._find_method("filter_id", filter_id)
        if method is None:
            cls.raise_unsupported_filter_id(filter_id)
        return method["type"] == MethodsType.crypto

    @classmethod
    def get_method_id(cls, filter_id) -> bytes:
        method = cls._find_method("filter_id", filter_id)
        if method is None:
            cls.raise_unsupported_filter_id(filter_id)
        return method["id"]

    @classmethod
    def get_coder(cls, filter) -> Dict[str, Any]:
        method = cls.get_method_id(filter["id"])
        if filter["id"] in [lzma.FILTER_LZMA1, lzma.FILTER_LZMA2, lzma.FILTER_DELTA]:
            properties: Optional[bytes] = lzma._encode_filter_properties(filter)  # type: ignore  # noqa
        else:
            properties = None
        return {
            "method": method,
            "properties": properties,
            "numinstreams": 1,
            "numoutstreams": 1,
        }

    @classmethod
    def needs_password(cls, coders) -> bool:
        for coder in coders:
            filter_id = SupportedMethods.get_filter_id(coder)
            if filter_id is None:
                continue
            if SupportedMethods.is_crypto_id(filter_id):
                return True
        return False

    @classmethod
    def raise_unsupported_method_id(cls, coder):
        if coder["method"] == COMPRESSION_METHOD.P7Z_BCJ2:
            raise UnsupportedCompressionMethodError(
                coder["method"],
                "BCJ2 filter is not supported by py7zr."
                " Please consider to contribute to XZ/liblzma project"
                " and help Python core team implementing it."
                " Or please use another tool to extract it.",
            )
        if coder["method"] == COMPRESSION_METHOD.MISC_DEFLATE64:
            raise UnsupportedCompressionMethodError(
                coder["method"],
                "DEFLATE64 compression is not supported by py7zr yet."
                " Please check the progress in py7zr project home page.",
            )
        if coder["method"] == COMPRESSION_METHOD.MISC_LZ4:
            raise UnsupportedCompressionMethodError(
                coder["method"], "Archive is compressed by an unsupported algorythm LZ4."
            )
        raise UnsupportedCompressionMethodError(
            coder["method"], "Archive is compressed by an unsupported compression algorythm."
        )

    @classmethod
    def raise_unsupported_filter_id(cls, filter_id):
        raise UnsupportedCompressionMethodError(
            filter_id, "Found an unsupported filter id is specified." "Please use another compression method."
        )


def get_methods_names(coders_lists: List[List[dict]]) -> List[str]:
    # list of known method names with a display priority order

    methods_namelist = [
        "LZMA2",
        "LZMA",
        "BZip2",
        "DEFLATE",
        "DEFLATE64",
        "delta",
        "COPY",
        "PPMd",
        "ZStandard",
        "LZ4*",
        "BCJ2*",
        "BCJ",
        "ARM",
        "ARMT",
        "IA64",
        "PPC",
        "SPARC",
        "7zAES",
    ]
    unsupported_methods = {
        COMPRESSION_METHOD.P7Z_BCJ2: "BCJ2*",
        COMPRESSION_METHOD.MISC_LZ4: "LZ4*",
    }
    methods_names = []
    for coders in coders_lists:
        for coder in coders:
            for m in SupportedMethods.methods:
                if coder["method"] == m["id"]:
                    methods_names.append(m["name"])
            if coder["method"] in unsupported_methods:
                methods_names.append(unsupported_methods[coder["method"]])
    return list(filter(lambda x: x in methods_names, methods_namelist))
