fix: support cookie-based auth, direct login often blocked by Instagram

- Try instaloader session file first
- Then cookies.txt (Mozilla format from browser extension)
- Then cookies.json (from browser extensions)
- Direct login as last resort with clear instructions

instagram_monitor.py

@@ -1,3 +1,4 @@
+import http.cookiejar
 import json
 import os
 import shutil
@@ -40,19 +41,72 @@ class InstagramMonitor:
             json.dump(self._state, f, indent=2)
 
     def login(self) -> bool:
-        try:
-            if self._session_path.exists():
+        # Method 1: load existing instaloader session file
+        if self._session_path.exists():
+            try:
                 self.loader.load_session_from_file(config.instagram_username, str(self._session_path))
-                logger.info("Session loaded from file")
+                logger.info("Session loaded from instaloader session file")
                 return True
+            except Exception as e:
+                logger.warning(f"Session file invalid: {e}")
 
-            self.loader.login(config.instagram_username, config.instagram_password)
-            self.loader.save_session_to_file(str(self._session_path))
-            logger.info("Logged in and session saved")
-            return True
-        except Exception as e:
-            logger.error(f"Login failed: {e}")
-            return False
+        # Method 2: load cookies.txt exported from browser
+        cookies_path = Path(config.download_dir) / "cookies.txt"
+        if cookies_path.exists():
+            try:
+                self._load_cookies_from_txt(cookies_path)
+                logger.info("Session loaded from cookies.txt")
+                return True
+            except Exception as e:
+                logger.warning(f"cookies.txt invalid: {e}")
+
+        # Method 3: load cookies.json exported from browser extension
+        cookies_json_path = Path(config.download_dir) / "cookies.json"
+        if cookies_json_path.exists():
+            try:
+                self._load_cookies_from_json(cookies_json_path)
+                logger.info("Session loaded from cookies.json")
+                return True
+            except Exception as e:
+                logger.warning(f"cookies.json invalid: {e}")
+
+        # Method 4: direct login (often blocked by Instagram now)
+        if config.instagram_password:
+            try:
+                self.loader.login(config.instagram_username, config.instagram_password)
+                self.loader.save_session_to_file(str(self._session_path))
+                logger.info("Logged in via direct login and session saved")
+                return True
+            except Exception as e:
+                logger.error(f"Direct login failed: {e}")
+                logger.info(
+                    "Use cookies.txt or cookies.json instead. "
+                    "Export from browser: install 'Get cookies.txt LOCALLY' extension, "
+                    "go to instagram.com, export, put file in /data/downloads/cookies.txt"
+                )
+                return False
+
+        logger.error("No valid session or credentials found")
+        return False
+
+    def _load_cookies_from_txt(self, path: Path) -> None:
+        cj = http.cookiejar.MozillaCookieJar(str(path))
+        cj.load(ignore_discard=True, ignore_expires=True)
+        self.loader.context._session.cookies.update(cj)
+        # Verify session works
+        instaloader.Profile.from_username(self.loader.context, config.instagram_username)
+
+    def _load_cookies_from_json(self, path: Path) -> None:
+        with open(path) as f:
+            cookies = json.load(f)
+        for cookie in cookies:
+            self.loader.context._session.cookies.set(
+                cookie["name"],
+                cookie["value"],
+                domain=cookie.get("domain", ".instagram.com"),
+                path=cookie.get("path", "/"),
+            )
+        instaloader.Profile.from_username(self.loader.context, config.instagram_username)
 
     def _get_profile_posts(self, username: str) -> list[instaloader.Post]:
         try: