v 0.0.1

app/utils.py

@@ -0,0 +1,83 @@
+import os
+
+from flask import Flask, request
+from typing import cast
+from itsdangerous import BadSignature, URLSafeSerializer
+from xkcdpass import xkcd_password
+
+from .models import Deck, Token, db
+
+def init_password_generator():
+    wordfile = xkcd_password.locate_wordfile()
+    global words
+    words = xkcd_password.generate_wordlist(wordfile=wordfile, min_length=3, max_length=6)
+
+def init_serializer(app: Flask):
+    global serializer
+    serializer = URLSafeSerializer(app.config['SECRET_KEY'])
+
+def get_available_decks(app: Flask):
+    slides_dir = app.config['SLIDES_DIR']
+    deck_names = [name for name in os.listdir(slides_dir) if os.path.isdir(os.path.join(slides_dir, name))]
+    deck_names.sort()
+    return deck_names
+
+def generate_username() -> str:
+    return cast(str, xkcd_password.generate_xkcdpassword(wordlist=words, numwords=3, delimiter="-"))
+
+def generate_password() -> str:
+    return cast(str, xkcd_password.generate_xkcdpassword(wordlist=words, numwords=5, delimiter="-"))
+
+def generate_token() -> Token:
+    max_tries = 100
+    for _ in range(max_tries):
+        user_name = generate_username()
+
+        if not db.session.execute(db.select(Token).where(Token.name == user_name)).scalar():
+            break
+    else:
+        raise RuntimeError(f"Unique username could not be generated after {max_tries} tries")
+
+    token = Token(user_name)
+    db.session.add(token)
+    db.session.commit()
+    return token
+
+def serialize_token(token: Token) -> str:
+    return serializer.dumps(token.id)
+
+def get_token() -> (Token | None):
+    token = request.cookies.get('access_token')
+    if not token:
+        return None
+    try:
+        id = serializer.loads(token)
+        token = db.session.execute(db.select(Token).filter_by(id=id)).scalar_one_or_none()
+        return token 
+    except BadSignature:
+        return None
+
+def get_unlocked_decks(token: (Token|None)):
+    if token is None:
+        return []
+    decks = token.decks
+    decks.sort(key=lambda deck: deck.deck)
+    return decks
+
+def is_deck_unlocked(deck: str):
+    token = get_token() 
+    if token:
+        return token.is_unlocked(deck)
+    else:
+        return False
+
+def update_token(decks: list[Deck]):
+    """
+    Adds the deck to the list of decks stored in the access token
+    """
+    token = get_token()
+    if token is None:
+        raise ValueError("Invalid token is set")
+    else:
+        token.decks = list(set(decks + token.decks))
+    db.session.commit()