import hashlib
import os
from decimal import Decimal, ROUND_FLOOR
from typing import List
from urllib.parse import urlsplit, urlunsplit
from .asset import Asset
from .exceptions import NoApproximationError, TypeError
from .strkey import StrKey
from .xdr import Xdr
MUXED_ACCOUNT_STARTING_LETTER: str = "M"
ED25519_PUBLIC_KEY_STARTING_LETTER: str = "G"
def sha256(data: bytes) -> bytes:
return hashlib.sha256(data).digest()
def best_rational_approximation(x):
x = Decimal(x)
int32_max = Decimal(2147483647)
fractions = [[Decimal(0), Decimal(1)], [Decimal(1), Decimal(0)]]
i = 2
while True:
if x > int32_max:
break
a = x.to_integral_exact(rounding=ROUND_FLOOR)
f = x - a
h = a * fractions[i - 1][0] + fractions[i - 2][0]
k = a * fractions[i - 1][1] + fractions[i - 2][1]
if h > int32_max or k > int32_max:
break
fractions.append([h, k])
if f.is_zero():
break
x = 1 / f
i = i + 1
n = fractions[len(fractions) - 1][0]
d = fractions[len(fractions) - 1][1]
if n.is_zero() or d.is_zero():
raise NoApproximationError("Couldn't find approximation.")
return {"n": int(n), "d": int(d)}
def pack_xdr_array(x):
if x is None:
return []
# if not isinstance(x, list):
# return [x]
return [x]
def unpack_xdr_array(x):
if not x:
return None
return x[0]
def hex_to_bytes(hex_string):
if isinstance(hex_string, bytes):
return hex_string
if isinstance(hex_string, str):
return bytes.fromhex(hex_string)
raise TypeError("`hex_string` should be a 32 byte hash or hex encoded string.")
def convert_assets_to_horizon_param(assets: List[Asset]) -> str:
assets_string = []
for asset in assets:
if asset.is_native():
assets_string.append(asset.type)
else:
assets_string.append("{}:{}".format(asset.code, asset.issuer))
return ",".join(assets_string)
def urljoin_with_query(base: str, path: str) -> str:
split_url = urlsplit(base)
query = split_url.query
real_path = split_url.path
if path:
real_path = os.path.join(split_url.path, path)
url = urlunsplit(
(split_url.scheme, split_url.netloc, real_path, query, split_url.fragment)
)
return url
def parse_ed25519_account_id_from_muxed_account_xdr_object(
data: Xdr.types.MuxedAccount,
) -> str:
if data.ed25519 is not None:
return StrKey.encode_ed25519_public_key(data.ed25519)
return StrKey.encode_ed25519_public_key(data.med25519.ed25519)
