1 files changed, 79 insertions, 0 deletions
diff --git a/pydis_site/utils/account.py b/pydis_site/utils/account.py
new file mode 100644
index 00000000..b4e41198
--- /dev/null
+++ b/pydis_site/utils/account.py
@@ -0,0 +1,79 @@
+from typing import Any, Dict
+
+from allauth.account.adapter import DefaultAccountAdapter
+from allauth.exceptions import ImmediateHttpResponse
+from allauth.socialaccount.adapter import DefaultSocialAccountAdapter
+from allauth.socialaccount.models import SocialLogin
+from django.contrib.auth.models import User as DjangoUser
+from django.contrib.messages import ERROR, add_message
+from django.http import HttpRequest
+from django.shortcuts import redirect
+from django.urls import reverse
+
+from pydis_site.apps.api.models import User as DiscordUser
+
+ERROR_CONNECT_DISCORD = ("You must login with Discord before connecting another account. "
+                         "Your account details have not been saved.")
+ERROR_JOIN_DISCORD = ("Please join the Discord server and verify that you accept the rules and "
+                      "privacy policy.")
+
+
+class AccountAdapter(DefaultAccountAdapter):
+    """An Allauth account adapter that prevents signups via form submission."""
+
+    def is_open_for_signup(self, request: HttpRequest) -> bool:
+        """
+        Checks whether or not the site is open for signups.
+
+        We override this to always return False so that users may never sign up using
+        Allauth's signup form endpoints, to be on the safe side - since we only want users
+        to sign up using their Discord account.
+        """
+        return False
+
+
+class SocialAccountAdapter(DefaultSocialAccountAdapter):
+    """An Allauth SocialAccount adapter that prevents signups via non-Discord connections."""
+
+    def is_open_for_signup(self, request: HttpRequest, social_login: SocialLogin) -> bool:
+        """
+        Checks whether or not the site is open for signups.
+
+        We override this method in order to prevent users from creating a new account using
+        a non-Discord connection, as we require this connection for our users.
+        """
+        if social_login.account.provider != "discord":
+            add_message(request, ERROR, ERROR_CONNECT_DISCORD)
+
+            raise ImmediateHttpResponse(redirect(reverse("home")))
+
+        try:
+            user = DiscordUser.objects.get(id=int(social_login.account.uid))
+        except DiscordUser.DoesNotExist:
+            add_message(request, ERROR, ERROR_JOIN_DISCORD)
+
+            raise ImmediateHttpResponse(redirect(reverse("home")))
+
+        if len(user.roles) <= 1:
+            add_message(request, ERROR, ERROR_JOIN_DISCORD)
+
+            raise ImmediateHttpResponse(redirect(reverse("home")))
+
+        return True
+
+    def populate_user(self, request: HttpRequest,
+                      social_login: SocialLogin,
+                      data: Dict[str, Any]) -> DjangoUser:
+        """
+        Method used to populate a Django User with data.
+
+        We override this so that the Django user is created with the username#discriminator,
+        instead of just the username, as Django users must have unique usernames. For display
+        purposes, we also set the `name` key, which is used for `first_name` in the database.
+        """
+        if social_login.account.provider == "discord":
+            discriminator = social_login.account.extra_data["discriminator"]
+            data["username"] = f"{data['username']}#{discriminator:0>4}"
+            data["name"] = data["username"]
+
+        return super().populate_user(request, social_login, data)