import json
from random import randint
import firebase_admin
from flask import Flask, Response, request
from flask_mail import Mail, Message
from firebase_admin import credentials, firestore, auth
from firebase_admin._auth_utils import EmailAlreadyExistsError

# Initialize Flask app
app = Flask(__name__)

# Initalize Mail instance
app.config['MAIL_SERVER']='smtp.gmail.com'
app.config['MAIL_PORT'] = 465
app.config['MAIL_USERNAME'] = 'legbarkr@gmail.com'
app.config['MAIL_PASSWORD'] = '!Password123'
app.config['MAIL_USE_TLS'] = False
app.config['MAIL_USE_SSL'] = True
mail = Mail(app)

# Initialize Firebase
firebase = firebase_admin.initialize_app(credentials.Certificate('firebase-key.json'))

@app.route('/')
def hello_world():
    return 'Hello World! I am the dog you tracked with the amazing sensor from LEG industries...kidding this is just the home page :)'

@app.route('/auth/register', methods=['POST'])
def register():
    body = request.json

    if body is None:
        return Response("{'error':'Invalid request - please provide a body'}", status=400, mimetype='application/json')

    email = body['email']
    password = body['password']
    name = body['name']
    deviceId = body['deviceid']
    
    # Some fields are not present
    if email is None or password is None or name is None or deviceId is None:
        return Response("{'error':'Entries missing'}", status=400, mimetype='application/json')

    # Register user with Firebase authentication
    try:
        user = auth.create_user(
            email=email,
            email_verified=False,
            password=password,
            display_name=name,
            disabled=False)
    except EmailAlreadyExistsError:
        return Response("{'error':'User with given email address already exists'}", status=409, mimetype='application/json')

    # Prompt the user to verify their email
    code = randint(100000, 999999)
    data = {
        u'code': code
    }
    firestore.client().collection(u'verification').document(user.uid).set(data)
    msg = Message('Please verify your email for BarkFinder', sender = 'TBA', recipients = [email])
    msg.body = '''Hey {}! Thank you for signing up for BarkFinder.
               In order to use our sevices, could you please verify your email address by logging in and entering this code {}'''.format(name, code)
    mail.send(msg)

    # Link the user to the device
    data = {
        u'devices': [deviceId]
    }
    firestore.client().collection(u'devices').document(user.uid).set(data)
    
    # User successfully created and linked to device
    resp = {"uid":user.uid}
    return Response(json.dumps(resp), status=201, mimetype='application/json')


# An example of reading data from Firebase
# Taken from Firebase documentation
@app.route('/example/read', methods=['GET'])
def exampleRead():
    doc_ref = firestore.client().collection(u'cities').document(u'LA')
    doc = doc_ref.get()
    if doc.exists:
        return f'Document data: {doc.to_dict()}'
    else:
        return u'No such document!'

# An example of saving data to Firebase
# Taken from Firebase documentation
# This should be a POST method...will change later
@app.route('/example/write', methods=['GET'])
def examnpleWrite():
    data = {
        u'name': u'Los Angeles',
        u'state': u'CA',
        u'country': u'USA'
    }

    # Add a new doc in collection 'cities' with ID 'LA'
    firestore.client().collection(u'cities').document(u'LA').set(data)
    return 'Saved to Firebase'

if __name__ == '__main__':
    app.run()