booking_calendar.py

from __future__ import print_function
from datetime import datetime
import time
import json
from os import name
import os.path
import base64
from googleapiclient.discovery import build
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request
from google.oauth2.credentials import Credentials

# If modifying these scopes, delete the file token.json.
SCOPES = ['https://www.googleapis.com/auth/calendar',
          'https://www.googleapis.com/auth/gmail.readonly']

vattnas_email = 'noreply@citybreak.com'
soderakra_email = 'noreply@dancenter.com'

month = {
    'jan': '01',
    'feb': '02',
    'mar': '03',
    'apr': '04',
    'maj': '05',
    'may': '05',
    'jun': '06',
    'jul': '07',
    'aug': '08',
    'sep': '09',
    'okt': '10',
    'oct': '10',
    'nov': '11',
    'dec': '12',
    'JAN': '01',
    'FEB': '02',
    'MAR': '03',
    'APR': '04',
    'MAJ': '05',
    'MAY': '05',
    'JUN': '06',
    'JUL': '07',
    'AUG': '08',
    'SEP': '09',
    'OKT': '10',
    'OCT': '10',
    'NOV': '11',
    'DEC': '12',
}


def get_booking_name(body, email):
    if email == soderakra_email:
        return "Okänd"
    split_line = []
    first_name = []
    last_name = []
    for line in body.splitlines():
        split_line = line.split()
        if split_line:
            if split_line[0] == 'Förnamn:':
                first_name = list(split_line[1:])
            elif split_line[0] == 'Efternamn:':
                last_name = list(split_line[1:])
    name_list = list(first_name)
    for ln in last_name:
        name_list.append(ln)
    return " ".join(name_list)


def get_start_and_end_dates(body, email):
    if email == vattnas_email:
        if 'Datum:' not in body:
            return None, None

        for line in body.splitlines():
            split_line = line.split()
            if split_line and split_line[0] == 'Datum:':
                start = f"{split_line[5]}-{month[split_line[4]]}-{split_line[3]}"
                end = f"{split_line[9]}-{month[split_line[8]]}-{split_line[7]}"
                return start, end
    elif email == soderakra_email:
        if 'Period:' not in body:
            return None, None
        words = body.split()
        for i, word in enumerate(words):
            if word and word == 'Period:':
                start_date_obj = datetime.strptime(
                    words[i+1], '%d/%m-%Y').date()
                end_date_obj = datetime.strptime(
                    words[i+3], '%d/%m-%Y').date()
                start = start_date_obj.strftime("%Y-%m-%d")
                end = end_date_obj.strftime("%Y-%m-%d")
                return start, end

    return None, None


def get_booking_id(body, email):
    if email == vattnas_email:
        split_line = []
        for line in body.splitlines():
            split_line = line.split()
            if split_line and split_line[0] == 'Bokningsnummer:':
                return split_line[1]
    elif email == soderakra_email:
        words = body.split()
        for index, word in enumerate(words):
            if word and (word == 'Reservationsnummer' or word == 'Bokning'):
                return words[index+1]
    return "0"


def get_booking_date(body, email):
    if email == vattnas_email:
        split_line = []
        for line in body.splitlines():
            split_line = line.split()
            if split_line and split_line[0] == 'Bokningsdatum:':
                return f"20{split_line[1][5] + split_line[1][6]}-{month[split_line[1][2] + split_line[1][3] + split_line[1][4]]}-{split_line[1][0] + split_line[1][1]}"
    elif email == soderakra_email:
        words = body.split()
        for i, word in enumerate(words):
            if word == 'Bokningen' and words[i+1] == 'gjordes' and words[i+2] == 'den':
                booking_date_obj = datetime.strptime(
                    words[i+3], '%d/%m-%Y').date()
                return booking_date_obj.strftime("%Y-%m-%d")
    return "0"


def setup_creds():
    # The file token.json stores the user's access and refresh tokens, and is
    # created automatically when the authorization flow completes for the first
    # time.
    creds = None
    if os.path.exists('token.json'):
        creds = Credentials.from_authorized_user_file('token.json', SCOPES)
    # If there are no (valid) credentials available, let the user log in.
    if not creds or not creds.valid:
        if creds and creds.expired and creds.refresh_token:
            creds.refresh(Request())
        else:
            flow = InstalledAppFlow.from_client_secrets_file(
                'credentials.json', SCOPES)
            creds = flow.run_local_server(port=0)
        # Save the credentials for the next run
        with open('token.json', 'w') as token:
            token.write(creds.to_json())
    return creds


def scan_and_get_message_bodies(service_gmail, email):
    if email == vattnas_email:
        print("==== Vattnäs ====")
    else:
        print("==== Söderåkra ====")
    print("Fetching all messages matching the query...")
    results = service_gmail.users().messages().list(
        userId='me', q=f'from:{email}').execute()
    messages = results.get('messages', [])
    message_bodies_new = []
    message_bodies_changed = []
    message_bodies_canceled = []

    if not messages:
        print('No messages found.')
    else:
        print(f"{len(messages)} messages found. Looking for bookings...")
        for message in messages:
            msg = service_gmail.users().messages().get(
                userId='me', id=message['id']).execute()
            for header in msg['payload']['headers']:
                if header['name'] != 'Subject':
                    continue
                if 'NY BOKNING' in header['value']:
                    body = base64.urlsafe_b64decode(msg['payload'].get(
                        "body").get("data").encode("ASCII")).decode("utf-8")
                    message_bodies_new.append(body)
                elif 'Ny bokning av ditt hus' in header['value']:
                    message_bodies_new.append(msg.get("snippet"))
                elif 'ÄNDRAD BOKNING' in header['value']:
                    body = base64.urlsafe_b64decode(msg['payload'].get(
                        "body").get("data").encode("ASCII")).decode("utf-8")
                    message_bodies_changed.append(body)
                elif 'AVBOKAD BOKNING' in header['value']:
                    body = base64.urlsafe_b64decode(msg['payload'].get(
                        "body").get("data").encode("ASCII")).decode("utf-8")
                    message_bodies_canceled.append(body)
                elif 'Afbestilling af booking på dit hus' in header['value']:
                    message_bodies_canceled.append(msg.get("snippet"))

    print(f"{len(message_bodies_new)} new bookings found.")
    print(f"{len(message_bodies_changed)} changed bookings found.")
    print(f"{len(message_bodies_canceled)} canceled bookings found.")
    return message_bodies_new, message_bodies_changed, message_bodies_canceled


def add_or_change_events(message_bodies, events, email):
    for body in message_bodies:
        start_date, end_date = get_start_and_end_dates(body, email)
        desc = "".join(line + "\n" for line in body.splitlines())
        booking_name = get_booking_name(body, email)
        booking_id = get_booking_id(body, email)
        booking_date = get_booking_date(body, email)
        place = 'SÖDERÅKRA' if email == soderakra_email else 'VATTNÄS'

        event = {
            'booking_id': booking_id,
            'booking_date': booking_date,
            'start': {'date': start_date},
            'end': {'date': end_date},
            'summary': f"{place}: {booking_name}, {booking_id}",
            'description': desc
        }
        if booking_id in events:
            if event['booking_date'] > events[booking_id]['booking_date']:
                events[booking_id] = event
                print("c", end="")
            else:
                print(".", end="")
        else:
            events[booking_id] = event
            print("a", end="")
    print()
    return events


def cancel_event(message_bodies_canceled, events, email):
    for body in message_bodies_canceled:
        booking_id = get_booking_id(body, email)
        if events.pop(booking_id, None):
            print("d", end="")
        else:
            print(".", end="")
    print()
    return events


def update_db(message_bodies_new, message_bodies_changed, message_bodies_canceled, email):
    print("Opening json file...")
    events = {}
    if email == vattnas_email:
        with open('events_vattnas.json') as events_file:
            if json_str := events_file.read():
                events = json.loads(json_str)
        print("Adding new events to json if not already in json...")
        events = add_or_change_events(message_bodies_new, events, email)
        print("Replacing events that were changed...")
        events = add_or_change_events(message_bodies_changed, events, email)
        print("Removing events that were canceled...")
        events = cancel_event(message_bodies_canceled, events, email)
        print("Updating json...")
        with open('events_vattnas.json', 'w') as events_file:
            events_file.write(json.dumps(events))
        print("Done")
    elif email == soderakra_email:
        with open('events_soderakra.json') as events_file:
            if json_str := events_file.read():
                events = json.loads(json_str)
        print("Adding new events to json if not already in json...")
        events = add_or_change_events(message_bodies_new, events, email)
        print("Replacing events that were changed...")
        events = add_or_change_events(message_bodies_changed, events, email)
        print("Removing events that were canceled...")
        events = cancel_event(message_bodies_canceled, events, email)
        print("Updating json...")
        with open('events_soderakra.json', 'w') as events_file:
            events_file.write(json.dumps(events))
        print("Done")

    return events


def get_booking_events(cal_events_all, email):
    cal_events = {}
    place = "VATTNÄS" if email == vattnas_email else "SÖDERÅKRA"
    for cal_event in cal_events_all['items']:
        if place in cal_event['summary']:
            cal_events[get_booking_id(
                cal_event['description'], email)] = cal_event

    return cal_events


def update_calendar(service, events, email):
    print('Fetching all calendar events...')
    cal_events_all = service.events().list(calendarId='primary').execute()
    cal_events = get_booking_events(cal_events_all, email)
    print(
        f"{len(cal_events_all['items'])} calendar events found. Looking for bookings...")
    print(f"{len(cal_events)} booking calendar events found.")
    exists = False
    changed = False
    print('Updating calendar according to json...')
    for event in events.values():
        booking_id = event['booking_id']
        if booking_id in cal_events:
            exists = True
            if event['description'] != cal_events[booking_id]['description']:
                service.events().delete(calendarId='primary',
                                        eventId=cal_events[booking_id]['id']).execute()
                changed = True
        if not exists:
            print("a", end="")
            e = service.events().insert(calendarId='primary', body=event).execute()

            print(f'''*** {e['summary'].encode('utf-8')} event added:
            Start: {e['start']['date']}
            End:   {e['end']['date']}''')
        elif changed:
            print("c", end="")
            e = service.events().insert(calendarId='primary', body=event).execute()

            print(f'''*** {e['summary'].encode('utf-8')} event updated:
            Start: {e['start']['date']}
            End:   {e['end']['date']}''')
        else:
            print(".", end="")
        exists = False
        changed = False
    print('\nRemoving canceled events from calendar...')
    for booking_id in cal_events.keys():
        if booking_id not in events:
            print("d")
            service.events().delete(calendarId='primary',
                                    eventId=cal_events[booking_id]['id']).execute()
            print(f"*** {cal_events[booking_id]['summary']} event removed")
        else:
            print(".", end="")
    print('Done')


def main():
    creds = setup_creds()

    service_cal = build('calendar', 'v3', credentials=creds)
    service_gmail = build('gmail', 'v1', credentials=creds)

    emails = [vattnas_email, soderakra_email]

    for email in emails:
        message_bodies_new, message_bodies_changed, message_bodies_canceled = scan_and_get_message_bodies(
            service_gmail, email)
        events = update_db(message_bodies_new, message_bodies_changed,
                           message_bodies_canceled, email)

        update_calendar(service_cal, events, email)


if __name__ == '__main__':
    main()