Initial release — PySide6 app for automatic GOG offline installer management

src/auth.py

@@ -0,0 +1,129 @@
+"""GOG OAuth2 authentication manager."""
+
+import json
+import time
+from pathlib import Path
+
+import requests
+from loguru import logger
+
+GOG_AUTH_URL = "https://auth.gog.com"
+CLIENT_ID = "46899977096215655"
+CLIENT_SECRET = "9d85c43b1482497dbbce61f6e4aa173a433796eeae2ca8c5f6129f2dc4de46d9"
+REDIRECT_URI = "https://embed.gog.com/on_login_success?origin=client"
+
+LOGIN_URL = (
+    f"https://login.gog.com/auth?client_id={CLIENT_ID}"
+    f"&redirect_uri={REDIRECT_URI}"
+    f"&response_type=code&layout=popup"
+)
+
+
+class AuthManager:
+    """Manages GOG OAuth2 tokens — exchange, refresh, persistence."""
+
+    def __init__(self, config_dir: Path) -> None:
+        self.config_dir = config_dir
+        self.auth_file = config_dir / "auth.json"
+        self.credentials: dict = {}
+        self.session = requests.Session()
+        self.session.headers.update({"User-Agent": "GOGUpdater/0.1"})
+        self._load()
+
+    def _load(self) -> None:
+        if self.auth_file.exists():
+            try:
+                self.credentials = json.loads(self.auth_file.read_text(encoding="utf-8"))
+            except (json.JSONDecodeError, OSError):
+                logger.warning("Failed to read auth.json, starting fresh")
+                self.credentials = {}
+
+    def _save(self) -> None:
+        self.config_dir.mkdir(parents=True, exist_ok=True)
+        self.auth_file.write_text(json.dumps(self.credentials, indent=2), encoding="utf-8")
+
+    @property
+    def is_logged_in(self) -> bool:
+        return bool(self.credentials.get("access_token"))
+
+    @property
+    def is_expired(self) -> bool:
+        if not self.is_logged_in:
+            return True
+        login_time = self.credentials.get("login_time", 0)
+        expires_in = self.credentials.get("expires_in", 0)
+        return time.time() >= login_time + expires_in
+
+    @property
+    def access_token(self) -> str | None:
+        if not self.is_logged_in:
+            return None
+        if self.is_expired:
+            if not self.refresh():
+                return None
+        return self.credentials.get("access_token")
+
+    def exchange_code(self, code: str) -> bool:
+        """Exchange authorization code for tokens."""
+        url = (
+            f"{GOG_AUTH_URL}/token"
+            f"?client_id={CLIENT_ID}"
+            f"&client_secret={CLIENT_SECRET}"
+            f"&grant_type=authorization_code"
+            f"&redirect_uri={REDIRECT_URI}"
+            f"&code={code}"
+        )
+        try:
+            response = self.session.get(url, timeout=15)
+        except (requests.ConnectionError, requests.Timeout):
+            logger.error("Failed to exchange authorization code — network error")
+            return False
+
+        if not response.ok:
+            logger.error(f"Failed to exchange authorization code — HTTP {response.status_code}")
+            return False
+
+        data = response.json()
+        data["login_time"] = time.time()
+        self.credentials = data
+        self._save()
+        logger.info("Successfully authenticated with GOG")
+        return True
+
+    def refresh(self) -> bool:
+        """Refresh access token using refresh_token."""
+        refresh_token = self.credentials.get("refresh_token")
+        if not refresh_token:
+            logger.error("No refresh token available")
+            return False
+
+        url = (
+            f"{GOG_AUTH_URL}/token"
+            f"?client_id={CLIENT_ID}"
+            f"&client_secret={CLIENT_SECRET}"
+            f"&grant_type=refresh_token"
+            f"&refresh_token={refresh_token}"
+        )
+        try:
+            response = self.session.get(url, timeout=15)
+        except (requests.ConnectionError, requests.Timeout):
+            logger.error("Failed to refresh token — network error")
+            return False
+
+        if not response.ok:
+            logger.error(f"Failed to refresh token — HTTP {response.status_code}")
+            return False
+
+        data = response.json()
+        data["login_time"] = time.time()
+        self.credentials = data
+        self._save()
+        logger.info("Token refreshed successfully")
+        return True
+
+    def logout(self) -> None:
+        """Clear stored credentials."""
+        self.credentials = {}
+        if self.auth_file.exists():
+            self.auth_file.unlink()
+        logger.info("Logged out")