views.py

from rest_framework import status
from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework.authtoken.models import Token
from rest_framework.parsers import JSONParser, FormParser, MultiPartParser

from django.http import Http404
from django.conf import settings
from django.db.models.signals import post_save
from django.dispatch import receiver

from users.models import User
from users.serializers import UserSerializer
from users.S3Client import S3Client

from botocore.exceptions import ClientError

import base64

# Create your views here.

"""
LOGIN
/o/token POST
HEADER - Content-Type: application/x-www-form-urlencoded
Body -  grant_type: password
        username: <email>
        password: <password>
        client_id: <client_id>
        client_secret: <client_secret>

REFRESH ACCESS TOKEN
/o/token POST
HEADER - Content-Type: application/x-www-form-urlencoded
Body -  grant_type: refresh_token
        refresh_token: <refresh_token>
        client_id: <client_id>
        client_secret: <client_secret>

LOGOUT
/o/revoke_token POST
HEADER - Content-Type: application/x-www-form-urlencoded
BODY -  token: <access_token>
        client_id: <client_id>
        client_secret: <client_secret>
"""

class UserSignup(APIView):
    """
    Allow a user to sign up and create a user account
    Does not require authentication or permissions
    """
    authentication_classes = ()
    permission_classes = ()

    def post(self, request, format=None):
        """
        Create a user.
        """
        serializer = UserSerializer(data=request.data)
        if serializer.is_valid():
            user = serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

class UserService(APIView):
    """
    Manage user requests

    Get
    Update
    Delete

    Requires default permissions
    """

    def get(self, request, format=None):
        """
        Get data of a user.
        QUERY PARAMETER: email="email@address.com"* OR id=<UID>
        """
        email = request.GET.get('email')
        id = request.GET.get('id')
        if email:
            user = get_user_by_email(email)
        elif id:
            user = get_user_by_id(id)
        else:
            return Response(status=status.HTTP_400_BAD_REQUEST)
        serializer = UserSerializer(user)
        return Response(serializer.data)

    def put(self, request, format=None):
        """
        Update information about a user.
        """
        email = get_email(request)
        user = get_user_by_email(email)
        serializer = UserSerializer(user, request.data, partial=True)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

    def delete(self, request, format=None):
        """
        Delete a user
        """
        email = get_email(request)
        user = get_user_by_email(email)
        user.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)

class MessagingService(APIView):
    authentication_classes = ()
    permission_classes = ()

    def get(self, request, format=None):
        user_id1 = request.GET.get('user1')
        user_id2 = request.GET.get('user2')
        user1 = get_user_by_pk(user_id1)
        user2 = get_user_by_pk(user_id2)
        messaging_payload = {
            "user1": {
                # "device_id" : user1.device_id,
                "is_on_chat": user1.is_on_chat,
            },
            "user2": {
                # "device_id" : user2.device_id,
                "is_on_chat": user2.is_on_chat,
            },
        }
        return Response(messaging_payload)

class ProfilePicture(APIView):
    
    #authentication_classes = ()
    #permission_classes = ()

    parser_classes = (JSONParser, MultiPartParser, FormParser)
    def create_file_name(self, user_id):
        return str(user_id) + ".jpg"
        #return 'test.jpg'
    
    def get(self, request, format=None):
        
        if not 'user_id' in request.GET.dict():
            return Response({"error": "User id not provided"}, status=status.HTTP_400_BAD_REQUEST)
        user_id = request.GET.get('user_id')
        #print("@@@@@@@@@@@@@@@@@@@@" + str(user_id) + " @@@@@@@@@@@")
        pic_name = self.create_file_name(user_id)        
        try:
            s3 = S3Client()
            pic_obj = s3.download_obj(pic_name)                
            ret_dict = {'user_id': int(user_id), 'profile_picture': base64.b64encode(pic_obj)}
        except ClientError as e:
            if e.response['Error']['Code'] == 'NoSuchKey':                
                return Response({"error": "Could not find profile picture"}, status=status.HTTP_404_NOT_FOUND)
            else:
                return Response({"error": "Something went wrong"}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
        except Exception as e:
            print(e)
            return Response({"error": "Something went wrong"}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
        return Response(ret_dict, status=status.HTTP_200_OK)

    
    
    def post(self, request, format=None):
        user_id = request.user.id
        if 'profile_picture' not in request.data:
            return Response({"error": "No file uploaded"}, status=status.HTTP_400_BAD_REQUEST)
        pic_obj = request.data['profile_picture']
        pic_name = self.create_file_name(user_id)
        try:
            s3 = S3Client()
            s3.upload_obj(pic_obj, pic_name)
        except Exception as e:
            print(e)
            return Response({"error": "Something went wrong"}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
        return Response({"success": True}, status=status.HTTP_201_CREATED)
    

### Non Router Functions ###
def get_user_by_email(email):
    """
    Returns user based on public key
    """
    try:
        return User.objects.get(email=email)
    except:
        raise Http404

def get_user_by_id(id):
    """
    Returns user based on public key
    """
    try:
        return User.objects.get(id=id)
    except:
        raise Http404

def get_user_by_pk(pk):
    try:
        return User.objects.get(pk=pk)
    except:
        raise Http404

def get_email(request):
    """
    Returns email of a user from the request, or raises Http404
    """
    try:
        return request.data["email"]
    except:
        raise Http404

def get_pk(request):
    """
    Returns public key from request
    """
    try:
        return request.data["id"]
    except:
        raise Http404