Add initial project files

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/utils/security.py

@@ -0,0 +1,34 @@
+from datetime import datetime, timedelta, timezone
+from typing import Optional
+
+from jose import JWTError, jwt
+from passlib.context import CryptContext
+
+from app.config import settings
+
+pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
+
+
+def hash_password(password: str) -> str:
+    return pwd_context.hash(password)
+
+
+def verify_password(plain: str, hashed: str) -> bool:
+    return pwd_context.verify(plain, hashed)
+
+
+def create_token(user_id: int) -> str:
+    expire = datetime.now(timezone.utc) + timedelta(minutes=settings.access_token_expire_minutes)
+    payload = {"sub": str(user_id), "exp": expire}
+    return jwt.encode(payload, settings.secret_key, algorithm=settings.algorithm)
+
+
+def decode_token(token: str) -> Optional[int]:
+    try:
+        payload = jwt.decode(token, settings.secret_key, algorithms=[settings.algorithm])
+        user_id = payload.get("sub")
+        if user_id is None:
+            return None
+        return int(user_id)
+    except JWTError:
+        return None