import time
import requests
import urllib.parse
import hashlib
import hmac
import base64
import json

# Read Kraken API key and secret stored in environment variables
api_url = "https://api.kraken.com"
api_key = ''
api_sec = ''

def get_kraken_signature(urlpath, data, secret):

    postdata = urllib.parse.urlencode(data)
    encoded = (str(data['nonce']) + postdata).encode()
    message = urlpath.encode() + hashlib.sha256(encoded).digest()

    mac = hmac.new(base64.b64decode(secret), message, hashlib.sha512)
    sigdigest = base64.b64encode(mac.digest())
    return sigdigest.decode()

# Attaches auth headers and returns results of a POST request
def kraken_request(uri_path, data, api_key, api_sec):
    headers = {}
    headers['API-Key'] = api_key
    # get_kraken_signature() as defined in the 'Authentication' section
    headers['API-Sign'] = get_kraken_signature(uri_path, data, api_sec)             
    req = requests.post((api_url + uri_path), headers=headers, data=data)
    return req

#Get balances for all accounts 
def getAccountBalances():
    # Construct the request and print the result
    resp = kraken_request('/0/private/Balance', {
    "nonce": str(int(time.time()*1000))
}, api_key, api_sec)
    return resp.json()['result']

#Get account coin balance passing in the coin
def getCoinBalance(coin):
    accounts = getAccountBalances()
    print(accounts)
    try: 
        return accounts[coin]
    except KeyError:
        print(f"You don't have any {coin} in your Kraken account, or you are using an invalid coin in coin_to_withdraw.")
        return 0

def getWithdrawalInfo(coin, my_wallet_address, my_balance):
    # Construct the request and print the result
    resp = kraken_request('/0/private/WithdrawInfo', {
    "nonce": str(int(1000*time.time())),
    "asset": coin,
    "key": my_wallet_address,
    "amount": my_balance
}, api_key, api_sec)
    print(f"getWithdrawalInfo: {resp.json()}")
    if(resp.json()['error'] != []):
        return resp.json()['error']
    return resp.json()['result']

def crypto_Withdrawal(coin, my_wallet_address, amount):
    # Construct the request and print the result
    resp = kraken_request('/0/private/Withdraw', {
    "nonce": str(int(1000*time.time())),
    "asset": coin,
    "key": my_wallet_address,
    "amount": amount
}, api_key, api_sec)
    return resp.json()

def lambda_handler(event, context):
    #Which coin do you want to withdraw? XXBT = Bitcoin, ETH = Ethereum etc
    coin_to_withdraw = "XXBT"
    #Which wallet do you want to withdraw to? Type in the name of your wallet as it appears in Kraken
    wallet_name = "COLDCARD Mk4"

    #Get the current balance of the coin you want to withdraw
    balance = getCoinBalance(coin_to_withdraw)
    if float(balance) == 0:
        print(f"Your balance for {coin_to_withdraw} is zero.")
    else:
        #Get the maximum allowable withdraw amount
        max_withdrawal = getWithdrawalInfo(coin_to_withdraw, wallet_name, balance)['limit']
        #Set the amount you want to withdraw. You can make this a static number (ie. 1 for 1 BTC) or you can set it to max_withdrawal or some factor of max_withdrawal
        amount_to_withdraw = max_withdrawal

        #Process the withdrawal
        print(crypto_Withdrawal(coin_to_withdraw, wallet_name, amount_to_withdraw))
    return {
        'statusCode': 200,
        'body': json.dumps('End of script')
    }