#!/usr/bin/env -S python3 -ttuI
# -*- python -*-
#-----------------------------------------------------------------------------#

import argparse
import io
import json
import requests
import sys
import types

base_url = 'https://api.starlingbank.com/api/v2'

#-----------------------------------------------------------------------------#

class StarlingClient:

    def __init__(self):
        self.tokens = self.read_tokens('main', 'payments')

    def read_tokens(self, *names):
        tokens = {}
        for name in names:
            with io.open(f'tokens/{name}.txt') as fh:
                tokens[name] = fh.read().rstrip()
        return tokens

    def get(self, path, token='main'):
        url = f'{base_url}/{path}'
        headers = {
            'Authorization': f'Bearer {self.tokens[token]}',
        }
        response = requests.get(url, headers=headers)
        response.raise_for_status()
        return json.loads(response.text, object_hook=lambda obj: types.SimpleNamespace(**obj))

    ### Low-level API wrappers ###

    def account_holder(self):
        return self.get('account-holder')

    def account_holder_individual(self):
        return self.get('account-holder/individual')

    def accounts(self):
        return self.get('accounts')

    def balance(self, accountUid):
        return self.get(f'accounts/{accountUid}/balance')

    def payees(self):
        return self.get('payees')

    ### Mid-level methods to munge the data from the low-level calls ###

    def formatted_balance(self, accountUid):
        balance = self.balance(accountUid).effectiveBalance
        if balance.currency == 'GBP':
            symbol = '£'
        elif balance.currency == 'EUR':
            symbol = '€'
        else:
            sys.exit(f'ERROR: Unsupported currency {balance.currency}')
        major_units = int(balance.minorUnits / 100)
        minor_units = balance.minorUnits % 100
        return f'{symbol}{major_units}.{minor_units:02d}'

    ### High-level methods which correspond to actions ###

    def default_action(self):
        holder = self.account_holder()
        holder_type = holder.accountHolderType
        if holder_type == 'INDIVIDUAL':
            details = self.account_holder_individual()
        else:
            sys.exit(f'ERROR: Unsupported account holder type {holder_type}')
        print('Customer details:')
        print(f'  Name: {details.firstName} {details.lastName}')
        print(f'  Email: <{details.email}>')
        print(f'  Phone: {details.phone}')
        accounts = self.accounts().accounts
        count = len(accounts)
        if count == 0:
            print('This customer has no bank accounts.')
        else:
            if count == 1:
                print('This customer has one bank account:')
            else:
                print(f'This customer has {count} bank accounts:')
            for account in accounts:
                balance = self.formatted_balance(account.accountUid)
                print(f'  {account.name} ({account.accountType}): {balance}')

    def list_payees(self):
        payees = self.payees().payees
        count = len(payees)
        if count == 0:
            print('There are no payees for this customer.')
        else:
            if count == 1:
                print('There is one payee for this customer:')
            else:
                print(f'There are {count} payees for this customer:')
            for payee in payees:
                print(f'  {payee.payeeName} ({payee.payeeType})')

#-----------------------------------------------------------------------------#

parser = argparse.ArgumentParser(
    usage='%(prog)s [options] [action [arg ...]]',
    description='Interacts with Starling Bank\'s API to manage bank accounts.',
    formatter_class=argparse.RawDescriptionHelpFormatter,
    epilog='''recognised actions and args:
                             - show customer and account details
  payees                     - list the customer's payees
  contacts <domain> [<name>] - get/set contacts for domain
  expire <domain>            - allow domain to auto-expire
  expiry                     - list domains with expiry info

To show the current lock state use "%(prog)s show <domain> status".
''')

parser.add_argument('-t', '--test', action='store_true', default=False,
                    help='use test servers rather than live servers')
parser.add_argument('-v', '--verbose', action='store_true', default=False,
                    help='print XML requests and responses')
parser.add_argument('action', help='which action to perform', nargs='*')
args = parser.parse_args()

client = StarlingClient()

action_args = args.action
if len(action_args) == 0:
    client.default_action()
else:
    action = action_args.pop(0)
    count = len(action_args)
    if action == 'payees':
        if count > 0:
            parser.error(f'Too many arguments for "{action}" action')
        client.list_payees()
    else:
        parser.error(f'Unknown action "{action}"')

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