# Copyright (c) 2021 Emanuele Bellocchia
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

"""Module for P2PKH address encoding/decoding."""

# Imports
from enum import Enum, auto, unique
from typing import Any, Union

from .addr_dec_utils import AddrDecUtils
from .addr_key_validator import AddrKeyValidator
from .iaddr_decoder import IAddrDecoder
from .iaddr_encoder import IAddrEncoder
from ..base58 import Base58Alphabets, Base58ChecksumError, Base58Decoder, Base58Encoder
from ..bech32 import BchBech32Decoder, BchBech32Encoder, Bech32ChecksumError
from ..ecc import IPublicKey
from ..utils.crypto import Hash160
from ..utils.misc import BytesUtils


@unique
class P2PKHPubKeyModes(Enum):
    """Enumerative for P2PKH public key modes."""

    COMPRESSED = auto()
    UNCOMPRESSED = auto()


class P2PKHAddrDecoder(IAddrDecoder):
    """
    P2PKH address decoder class.
    It allows the Pay-to-Public-Key-Hash address decoding.
    """

    @staticmethod
    def DecodeAddr(addr: str,
                   **kwargs: Any) -> bytes:
        """
        Decode a P2PKH address to bytes.

        Args:
            addr (str): Address string

        Other Parameters:
            net_ver (bytes)                        : Expected net address version
            base58_alph (Base58Alphabets, optional): Base58 alphabet (default: Bitcoin alphabet)

        Returns:
            bytes: Public key hash bytes

        Raises:
            ValueError: If the address encoding is not valid
        """
        net_ver_bytes = kwargs["net_ver"]
        base58_alph = kwargs.get("base58_alph", Base58Alphabets.BITCOIN)

        try:
            addr_dec_bytes = Base58Decoder.CheckDecode(addr, base58_alph)
        except Base58ChecksumError as ex:
            raise ValueError("Invalid base58 checksum") from ex

        # Validate length
        AddrDecUtils.ValidateLength(addr_dec_bytes,
                                    Hash160.DigestSize() + len(net_ver_bytes))
        # Validate and remove prefix
        return AddrDecUtils.ValidateAndRemovePrefix(addr_dec_bytes, net_ver_bytes)


class P2PKHAddrEncoder(IAddrEncoder):
    """
    P2PKH address encoder class.
    It allows the Pay-to-Public-Key-Hash address encoding.
    """

    @staticmethod
    def EncodeKey(pub_key: Union[bytes, IPublicKey],
                  **kwargs: Any) -> str:
        """
        Encode a public key to P2PKH address.

        Args:
            pub_key (bytes or IPublicKey): Public key bytes or object

        Other Parameters:
            net_ver (bytes)                          : Net address version
            base58_alph (Base58Alphabets, optional)  : Base58 alphabet, Bitcoin alphabet by default
            pub_key_mode (P2PKHPubKeyModes, optional): Public key mode, compressed key by default

        Returns:
            str: Address string

        Raises:
            ValueError: If the public key is not valid
            TypeError: If the public key is not secp256k1
        """
        net_ver_bytes = kwargs["net_ver"]
        base58_alph = kwargs.get("base58_alph", Base58Alphabets.BITCOIN)
        pub_key_mode = kwargs.get("pub_key_mode", P2PKHPubKeyModes.COMPRESSED)

        pub_key_obj = AddrKeyValidator.ValidateAndGetSecp256k1Key(pub_key)
        pub_key_bytes = (pub_key_obj.RawCompressed().ToBytes()
                         if pub_key_mode == P2PKHPubKeyModes.COMPRESSED
                         else pub_key_obj.RawUncompressed().ToBytes())

        return Base58Encoder.CheckEncode(net_ver_bytes + Hash160.QuickDigest(pub_key_bytes), base58_alph)


class BchP2PKHAddrDecoder(IAddrDecoder):
    """
    Bitcoin Cash P2PKH address decoder class.
    It allows the Bitcoin Cash P2PKH decoding.
    """

    @staticmethod
    def DecodeAddr(addr: str,
                   **kwargs: Any) -> bytes:
        """
        Decode a Bitcoin Cash P2PKH address to bytes.

        Args:
            addr (str): Address string

        Other Parameters:
            hrp (str)      : Expected HRP
            net_ver (bytes): Expected net address version

        Returns:
            bytes: Public key hash bytes

        Raises:
            ValueError: If the address encoding is not valid
        """
        hrp = kwargs["hrp"]
        net_ver_bytes = kwargs["net_ver"]

        try:
            net_ver_bytes_got, addr_dec_bytes = BchBech32Decoder.Decode(hrp, addr)
        except Bech32ChecksumError as ex:
            raise ValueError("Invalid bech32 checksum") from ex

        # Check net version
        if net_ver_bytes != net_ver_bytes_got:
            raise ValueError(f"Invalid net version (expected {BytesUtils.ToHexString(net_ver_bytes)}, "
                             f"got {BytesUtils.ToHexString(net_ver_bytes_got)})")
        # Validate length
        AddrDecUtils.ValidateLength(addr_dec_bytes,
                                    Hash160.DigestSize())
        return addr_dec_bytes


class BchP2PKHAddrEncoder(IAddrEncoder):
    """
    Bitcoin Cash P2PKH address encoder class.
    It allows the Bitcoin Cash P2PKH encoding.
    """

    @staticmethod
    def EncodeKey(pub_key: Union[bytes, IPublicKey],
                  **kwargs: Any) -> str:
        """
        Encode a public key to Bitcoin Cash P2PKH address.

        Args:
            pub_key (bytes or IPublicKey): Public key bytes or object

        Other Parameters:
            hrp (str)      : HRP
            net_ver (bytes): Net address version

        Returns:
            str: Address string

        Raises:
            ValueError: If the public key is not valid
            TypeError: If the public key is not secp256k1
        """
        hrp = kwargs["hrp"]
        net_ver_bytes = kwargs["net_ver"]

        pub_key_obj = AddrKeyValidator.ValidateAndGetSecp256k1Key(pub_key)
        return BchBech32Encoder.Encode(hrp,
                                       net_ver_bytes,
                                       Hash160.QuickDigest(pub_key_obj.RawCompressed().ToBytes()))


# Deprecated: only for compatibility, Encoder classes shall be used instead
P2PKHAddr = P2PKHAddrEncoder
BchP2PKHAddr = BchP2PKHAddrEncoder