#!/usr/bin/env python3
# Copyright (c) 2016 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Encode and decode BASE58, P2PKH and P2SH addresses."""

from .script import CScript, hash160, hash256
from .util import bytes_to_hex_str, hex_str_to_bytes

chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'


def byte_to_base58(b, version):
    result = ''
    str = bytes_to_hex_str(b)
    str = bytes_to_hex_str(chr(version).encode('latin-1')) + str
    checksum = bytes_to_hex_str(hash256(hex_str_to_bytes(str)))
    str += checksum[:8]
    value = int('0x' + str, 0)
    while value > 0:
        result = chars[value % 58] + result
        value //= 58
    while (str[:2] == '00'):
        result = chars[0] + result
        str = str[2:]
    return result

# TODO: def base58_decode


def keyhash_to_p2pkh(hash, main=False):
    assert (len(hash) == 20)
    version = 0 if main else 111
    return byte_to_base58(hash, version)


def scripthash_to_p2sh(hash, main=False):
    assert (len(hash) == 20)
    version = 5 if main else 196
    return byte_to_base58(hash, version)


def key_to_p2pkh(key, main=False):
    key = check_key(key)
    return keyhash_to_p2pkh(hash160(key), main)


def script_to_p2sh(script, main=False):
    script = check_script(script)
    return scripthash_to_p2sh(hash160(script), main)


def check_key(key):
    if (type(key) is str):
        key = hex_str_to_bytes(key)  # Assuming this is hex string
    if (type(key) is bytes and (len(key) == 33 or len(key) == 65)):
        return key
    assert(False)


def check_script(script):
    if (type(script) is str):
        script = hex_str_to_bytes(script)  # Assuming this is hex string
    if (type(script) is bytes or type(script) is CScript):
        return script
    assert(False)