from cryptography.fernet import Fernet
from simple_logger_handler import setup_logger

logger = setup_logger(__name__)

try:
	with open("/etc/secrets/encryption_key","rb") as file:
			  encryption_key = file.read()
except FileNotFoundError:
	logger.fatal("[Secret Handler] Encryption key not found")
	raise
except Exception as e:
	logger.fatal(f"[Secret Handler] Failed to read encryption key: {e}")
	raise

fernet = Fernet(encryption_key)

def encrypt_token(token:str)->str:
	return fernet.encrypt(token.encode()).decode()

def decrypt_token(token:str)->str:
	return fernet.decrypt(token.encode()).decode()

def return_credentials(path: str)->str:
	try:
		with open (path) as file:
			return file.read().strip()
	except FileNotFoundError:
		logger.fatal(f"[Secret Handler] Secret file not found: {path}")
		raise
	except Exception as e:
		logger.fatal(f"[Secret Handler] Failed to read secret file {path}: {e}")
		raise

async def database_lookup_by_user_id(routing_key: str, db_manager):
	try:
		user_id = int(routing_key.split('.')[-1])
		logger.debug(f"[DB] Looking up tokens for user_id={user_id}")
	except ValueError:
		logger.error(f"[DB] Invalid user id supplied:{routing_key}")
		return []

	async with db_manager.acquire() as conn:
		async with conn.cursor() as cur:
			await cur.execute("SELECT token_id AS uuid,token FROM device_tokens WHERE user_id=%s",
					(user_id,))
			logger.debug(f"[DB] Executed query for user_id={user_id}")
			if cur.description:
				rows = await cur.fetchall()
				logger.debug(f"[DB] Retrieved {len(rows)} tokens for user_id={user_id}")
				return rows
			logger.debug(f"[DB] No tokens found for user_id={user_id}")
			return []

async def database_lookup_by_uuid(uuid: str, db_manager):
	logger.debug(f"[DB] Looking up token for uuid={uuid}")
	async with db_manager.acquire() as conn:
		async with conn.cursor() as cur:
			await cur.execute("SELECT token_id AS uuid,token FROM device_tokens WHERE token_id=%s",
					(uuid,))
			logger.debug(f"[DB] Executed query for uuid={uuid}")
			if cur.description:
				rows = await cur.fetchall()
				logger.debug(f"[DB] Retrieved {len(rows)} tokens for uuid={uuid}")
				return rows
			logger.debug(f"[DB] No token found for uuid={uuid}")
			return []

async def remove_inactive_push_token(uuid :str, db_manager):
	logger.debug(f"[DB] Expiring token for uuid={uuid}")
	async with db_manager.acquire() as conn:
		async with conn.cursor() as cur:
			await cur.execute("UPDATE device_tokens SET status='expired' WHERE token_id=%s",
					 (uuid,))
			success = cur.rowcount > 0
			logger.debug(f"[DB] Token expiration for uuid={uuid} success={success}")
			return success