init: inital commit

lib/localiser/domain/users.ex

@@ -0,0 +1,32 @@
+defmodule Localiser.Domain.Users do
+  alias Localiser.Repo
+  alias Localiser.Domain.Schema.User
+
+  def get_user!(id), do: Repo.get!(User, id)
+
+  def get_user_by_username(username) do
+    Repo.get_by(User, username: username)
+  end
+
+  def create_user(attrs) do
+    %User{}
+    |> User.changeset(attrs)
+    |> Repo.insert()
+  end
+
+  def authenticate_user(username, password) do
+    user = get_user_by_username(username)
+
+    cond do
+      user && Argon2.verify_pass(password, user.password_hash) ->
+        {:ok, user}
+
+      user ->
+        {:error, :invalid_credentials}
+
+      true ->
+        Argon2.no_user_verify()
+        {:error, :invalid_credentials}
+    end
+  end
+end