"""
API data snapshot script.

This quickly snapshots the API output for all whitelisted UPCs.
"""
from __future__ import print_function

import os.path
import sys


# create import path for ETL source files. Needed to load utils.
_here = os.path.dirname(os.path.realpath(__file__))
_etl_path = os.path.join(os.path.dirname(_here), 'etls')
sys.path.append(_etl_path)


from datetime import datetime
import json
import os

from urllib.request import Request, urlopen
from flows.constant import FILM_WHITELIST


API_URL_FORMAT = 'https://workstation.theorchard.com/api/film-transparency/' \
    'release/{upc}/profit-loss'


def ask(prompt):
    """Backwards compatible input prompt.

    Args:
        prompt (str): terminal prompt message.

    Returns:
        str: user provided string value.
    """
    if sys.version_info[0] == 3:
        return input(prompt)
    return raw_input(prompt)


def get_token():
    """Prompt to have user submit a GRASS token."""
    print("""
    Need to first get the GRASS session token:

    1. Log into workstation (any account will do).
    2. Go to https://workstation.theorchard.com/grasssession
    3. Copy the token value, without quotes
    """)

    return ask('Input token value: ')


def get_api_data(upc, token):
    """Grab data from ows-film-transparency API.

    Args:
        upc (str): target film's UPC.
        token (str): GRASS token.

    Returns:
        dict: JSON decoded data object from the API.
    """
    url = API_URL_FORMAT.format(upc=upc)
    print('Getting data for UPC:', upc)
    request = Request(url=url, headers={'session': token})
    with urlopen(request) as response:
        return json.load(response)


def save_data(upc, data):
    """Save data to a timestamped folder.

    Args:
        upc (str): target film's UPC.
        data (dict): native python data object to save as JSON.
    """
    datestamp = datetime.now().strftime('%Y-%m-%d')
    os.makedirs(datestamp, exist_ok=True)
    filename = '{upc}.json'.format(upc=upc)
    target = os.path.join(datestamp, filename)
    print('Saving data to', target)
    with open(target, 'wt+', encoding='utf-8') as fh:
        json.dump(data, fh, indent=4)


if __name__ == '__main__':
    token = get_token()
    for upcs in FILM_WHITELIST.values():
        for upc in upcs:
            output = get_api_data(upc, token)
            save_data(upc, output)