import time
import sys
import json
import base64
import hashlib
import hmac
import urllib.request
import requests
import datetime

def placeLimitOrder(trade_symbol, trade_size, trade_leverage, limit_price):
    # Infinite loop (can be exited via keyboard interrupt)
    try:
        api_path = '/0/private/AddOrder'
        api_nonce = str(int(time.time()*1000))
        api_post = 'nonce=%(api_nonce)s&pair=%(symbol)s&type=%(direction)s&ordertype=limit&price=%(price)f&volume=%(volume)f&leverage=%(leverage)s' % {'api_nonce':api_nonce, 'symbol':trade_symbol, 'direction':'buy', 'price':limit_price,'volume':trade_size, 'leverage':str(trade_leverage) if trade_leverage > 0 else 'none'}
        api_sha256 = hashlib.sha256(api_nonce.encode('utf8') + api_post.encode('utf8'))
        api_hmac = hmac.new(base64.b64decode(api_key_private), api_path.encode('utf8') + api_sha256.digest(), hashlib.sha512)
        api_signature = base64.b64encode(api_hmac.digest())
        
        api_request = urllib.request.Request('https://api.kraken.com/0/private/AddOrder', api_post.encode('utf8'))
        api_request.add_header('API-Key', api_key_public)
        api_request.add_header('API-Sign', api_signature)
        api_request.add_header('User-Agent', 'Kraken trading bot example')
        api_response = urllib.request.urlopen(api_request).read().decode()
        api_data = json.loads(api_response)
    except Exception as error:
        print('Failed (%s)' % error)
    else:
        print('Done (%s)' % api_response if len(api_data['error']) == 0 else 'Error (%s)' % api_data['error'])

    return True

#Prints list of tradable currency pairs
def getTradableAssetPairs():
    resp = requests.get('https://api.kraken.com/0/public/AssetPairs')
    return resp.json()['result'].keys()

#takes asset like "XBT" or "ETH" and returns asset details
def getAssetInfo(asset):
    resp = requests.get(f'https://api.kraken.com/0/public/Assets?asset={asset}')
    return resp.json()

#takes trading pair like XXBTZUSD or ETHUSD and gives details
def getTickerInfo(trading_pair):
    resp = requests.get(f'https://api.kraken.com/0/public/Ticker?pair={trading_pair}')
    values = list(resp.json()['result'].values())
    return {'symbol' : trading_pair,
    'ask':values[0]['a'],
    'bid':values[0]['b'],
    'last_trade_closed':values[0]['c'],
    'volume':values[0]['v'],
    'volume_weighted_average_price':values[0]['p'],
    'num_trades':values[0]['t'],
    'low':values[0]['l'],
    'high':values[0]['h'],
    'open':values[0]['o']}

#Get balances for all accounts 
def getAccountBalances():
    try:
        print("trying")
        api_path = '/0/private/Balance'
        api_nonce = str(int(time.time()*1000))
        api_post = 'nonce=%(api_nonce)s' % {'api_nonce':api_nonce}
        api_sha256 = hashlib.sha256(api_nonce.encode('utf8') + api_post.encode('utf8'))
        api_hmac = hmac.new(base64.b64decode(api_key_private), api_path.encode('utf8') + api_sha256.digest(), hashlib.sha512)
        api_signature = base64.b64encode(api_hmac.digest())

        api_request = urllib.request.Request('https://api.kraken.com'+api_path, api_post.encode('utf8'))
        api_request.add_header('API-Key', api_key_public)
        api_request.add_header('API-Sign', api_signature)
        api_response = urllib.request.urlopen(api_request).read().decode()
        api_data = json.loads(api_response)

    except Exception as error:
        print('Failed (%s)' % error)
    else:
        #print('Done (%s)' % api_response if len(api_data['error']) == 0 else 'Error (%s)' % api_data['error'])
        return api_data['result']

    return True

#Get account coin balance passing in the coin
def getCoinBalance(coin):
    accounts = getAccountBalances()
    return accounts[coin]

#Gets bid price of coin pair (ie. XXBTZUSD, ETHUSD, etc)
def getCoinBid(trading_pair):
    return getTickerInfo(trading_pair)['bid'][0]

# Configure API key (copy/paste from account management)
api_key_public = ''
api_key_private = ''

def lambda_handler(event, context):
    symbol = "XXBTZUSD"
    usdAmount = 10
    trade_size = round(usdAmount/float(getCoinBid("XXBTZUSD")),6)
    print(trade_size)
    leverage = 0
    limit_price = float(getCoinBid("XXBTZUSD"))
    print(limit_price)
    
    placeLimitOrder(symbol, trade_size, leverage, limit_price)
    return {
        'statusCode': 200,
        'body': json.dumps('End of script')
    }