from requests import get
from django.conf import settings
from gauth.auth_utils import get_gmb_id
from gauth.location_utils import get_all_location_ids
from django.db.models import Max
from .models import Review, Reply
from gauth.models import Location

from django.utils import timezone


ACCESS_TOKEN_URI = settings.HOST_URI + '/token'

STAR_REVIEW_NUM = {'STAR_RATING_UNSPECIFIED': 0, 'ONE': 1, 'TWO': 2, 'THREE': 3, 'FOUR': 4, 'FIVE': 5}
USER, GMB_ID = get_gmb_id()


def get_review_list_url(loc_id, next_page_token=''):
    # An helper function that make a url that need to consume GMB review api
    return 'https://mybusiness.googleapis.com/v4/accounts/' + GMB_ID + '/locations/' + loc_id + '/reviews?pageToken='+next_page_token


def get_max_date(loc_id):
    # Function that takes a location id and return the latest updated review.
    largest = Review.objects.filter(location_id=loc_id).aggregate(Max('create_time'))['create_time__max']
    max_date = largest if largest else '1970-01-11 17:41:17.532740'
    return max_date


def get_auth_header():
    access_token = get(ACCESS_TOKEN_URI).text
    headers = {
        'authorization': 'Bearer ' + access_token,
        'content-type': 'application/json'
    }
    return headers


def filter_unrecorded_review_by_date(reviews, max_date):
    # A function that return only those reviews whose has larger value than
    # the max create_time value in review database.
    filtered_reviews = []
    for rev in reviews:
        if rev['createTime'] >= str(max_date):
            filtered_reviews.append(rev)
    return filtered_reviews


def insert_review_into_database(unrecorded_reviews, loc):
    for review in unrecorded_reviews:
        review_id = review.get('reviewId')
        # Check the review already in database then We don't need to store again.
        rev = Review.objects.filter(pk=review_id).first()
        if rev:
            continue
        comment = review.get('comment')
        create_time = review.get('createTime')
        update_time = review.get('updateTime')
        star_rating = STAR_REVIEW_NUM[review.get('starRating')]
        reviewer = review.get('reviewer')
        reviewer_name = reviewer.get('displayName')
        reviewer_photo = reviewer.get('profilePhotoUrl')
        review_reply = review.get('reviewReply')
        if review_reply:
            replied_text = review_reply.get('comment')
            create_time = review_reply.get('updateTime')
            reply = Reply.objects.create(replied_text=replied_text, create_time=create_time)
        else:
            reply = None

        review = Review(
            review_id=review_id,
            comment=comment,
            create_time=create_time,
            update_time=update_time,
            star_rating=star_rating,
            reviewer_name=reviewer_name,
            reviewer_photo=reviewer_photo,
            location=loc,
            reply=reply
        )
        review.save()


def fetch_all_review(loc_id):
    loc = Location.objects.get(pk=loc_id)
    max_date = get_max_date(loc_id)
    next_page_token = ''
    headers = get_auth_header()
    while True:
        url = get_review_list_url(loc_id, next_page_token)
        res = get(url, headers=headers)
        if res.status_code == 401:
            headers = get_auth_header()
            continue
        data = res.json()
        reviews = data['reviews']
        unrecorded_reviews = filter_unrecorded_review_by_date(reviews, max_date)
        if len(unrecorded_reviews) != 0:
            insert_review_into_database(unrecorded_reviews, loc)
        next_page_token = data.get('nextPageToken')
        if next_page_token is None:
            break


def populate_reviews():
    start = timezone.now()
    locations = get_all_location_ids()
    for loc_id in locations:
        fetch_all_review(loc_id)
    end = timezone.now()
    elapsed = end - start
    print('-----------------------------------------------------------------------------------------')
    print(f'Elapsed time: {elapsed.seconds//60} minutes and {elapsed.seconds % 60} secs.')
    print('-----------------------------------------------------------------------------------------')