import asyncio
from contextlib import asynccontextmanager
import os

import uvicorn
from fastapi import Depends, FastAPI, HTTPException, Request, APIRouter

from db_module import close_connection_pool, create_connection_pool, get_db, start_healthcheck_thread
from feed_handler import grab_gitea_release_information, grab_royal_road_chapter_information, build_gitea_runner, RoyalRoadStory
from metrics_server import REQUEST_COUNTER, metrics_api
from secret_manager import cleanup_secret_files, get_secret
from send_notifications import NotificationClient, NotificationUnavailableError, NotificationError
from simple_logger_handler import LOG_LEVEL, setup_logger
from auth_config import Caller, auth 
from service_auth import UserId

logger = setup_logger(__name__)


@asynccontextmanager
async def lifespan(app: FastAPI):
	logger.info("[FastAPI] Starting application...")
	app.state.notifier = NotificationClient()
	app.state.gitea_token = get_secret("GITEA_TOKEN","/etc/secrets/gitea_token")

	logger.info("[FastAPI] Creating MySQL connection pool...")
	create_connection_pool("royalRoadPool")

	start_healthcheck_thread()
	logger.info("[FastAPI] MySQL healthcheck thread started.")

	SECRET_PATHS = frozenset({
		"/etc/secrets/gitea_token",
		"/etc/secrets/api_key",
		"/etc/secrets/db_username",
		"/etc/secrets/db_password"
	})
	cleanup_secret_files(SECRET_PATHS)

	yield
	logger.info("[FastAPI] Closing MySQL connection pool...")
	close_connection_pool()
	logger.info("[FastAPI] Shutdown complete.")

api = FastAPI(
		title="Docker Repository Query",
		description="Queries Dockerhub and GHCR for new docker images",
		version="1.0.0",
		lifespan=lifespan,
		dependencies=[Depends(auth.authenticate)],
)

@api.middleware("http")
async def prometheus_middleware(request: Request, call_next):
	logger.debug(f"[FastAPI] Incoming request: {request.method} {request.url.path}")
	status = 500
	try:
		response = await call_next(request)
		status = response.status_code
		logger.debug(f"[FastAPI] Request processed with status {status}")
	except Exception as e:
		logger.error(f"[FastAPI] Exception occurred: {e}", exc_info=True)
		raise
	finally:
		REQUEST_COUNTER.labels(request.method, request.url.path, status).inc()
		logger.debug(f"[FastAPI] Counter incremented for {request.method} {request.url.path} [{status}]")
	return response


user_router = APIRouter(dependencies=[Depends(auth.require(Caller.GATEWAY))])
scheduler_router = APIRouter(dependencies=[Depends(auth.require(Caller.SCHEDULER))])

@scheduler_router.get("/gitea")
def get_release_information(request: Request, db = Depends(get_db)):
	"""
	Checks for new Gitea releases and updates the database accordingly.

	Behaviour:
		- Fetches all active Gitea feeds and their last known release link.
		- Queries each feed for its latest release.
		- Updates `last_entry` if the latest release link differs from the stored one.
		- Sends a notification for each changed release.
		- A failure on one feed is logged and the remaining feeds are still checked.

	Returns:
		A JSON object with checked/new/error counts. If any feed failed,
		a 500 is returned with the same counts as the detail.
	"""
	logger.info("[FastAPI] Checking for new Gitea releases")
	results = {"checked": 0, "new": 0, "errors": 0}
	with db.cursor() as cursor:
		cursor.execute(
			"SELECT id, rss_feed, feed_name, last_entry "
			"FROM rss_feeds WHERE active = 1 AND type = %s",
			("gitea",),
		)
		feeds = cursor.fetchall()
		logger.debug(f"[FastAPI] Found {len(feeds)} active Gitea feeds to check.")

		for feed_id, rss_feed, feed_name, last_entry in feeds:
			results["checked"] += 1
			try:
				release_title, link = grab_gitea_release_information(rss_feed)
				logger.debug(f"[FastAPI] ID:{feed_id},RSS Feed {rss_feed}: db={last_entry}, online={link}")

				if link == last_entry:
					continue

				logger.info(f"[FastAPI] Release change for ID {feed_id}: {release_title}")
				request.app.state.notifier.send(
					title=feed_name,
					body=release_title,
					link=link,
					category="utility"
				)
				cursor.execute(
					"UPDATE rss_feeds SET last_entry = %s WHERE id = %s",
					(link, feed_id),
				)
				db.commit()
				logger.debug(f"[FastAPI] Notification sent and database updated for Gitea feed ID {feed_id}")
				results["new"] += 1

				if link.startswith("https://gitea.com/gitea/runner/releases/tag/v"):
					gitea_build_success = build_gitea_runner(release_title, request.app.state.gitea_token)
					logger.info(f"[FastAPI] Gitea build ran successfully:{gitea_build_success}")

			except Exception as e:
				db.rollback()
				results["errors"] += 1
				logger.error(
					f"[FastAPI] Failed for feed ID {feed_id} ({rss_feed}): {e}",
					exc_info=True,
				)

	if results["errors"]:
		logger.warning(f"[FastAPI] Gitea check finished with errors: {results}")
		raise HTTPException(status_code=500, detail=results)

	logger.info(f"[FastAPI] Gitea check complete: {results}")
	return results

@scheduler_router.get("/royalroad")
def get_chapters(request: Request, db = Depends(get_db)):
	"""
	Checks for new Royalroad chapters and updates the database accordingly.

	Behaviour:
		- Fetches all active stories and their last known chapter ID.
		- Queries Royalroad for each story's latest chapter.
		- Updates `last_entry` if a new chapter is found.
		- Sends a notification for any newly discovered chapters.
		- A failure on one story is logged and the remaining stories are still checked.

	Returns:
		A JSON object with checked/new/error counts. If any story failed,
		a 500 is returned with the same counts as the detail.
	"""
	logger.info("[FastAPI] Checking for new Royalroad chapters")
	results = {"checked": 0, "new": 0, "errors": 0}
	with db.cursor() as cursor:
		cursor.execute(
			"SELECT id, rss_feed, last_entry "
			"FROM rss_feeds WHERE active = 1 AND type = %s",
			("royalroad",),
		)
		feeds = cursor.fetchall()
		logger.debug(f"[FastAPI] Found {len(feeds)} active stories to check.")

		cache: dict[str, str | None] = {} 
		for feed_id, rss_feed, last_entry in feeds:
			results["checked"] += 1
			try:
				story = grab_royal_road_chapter_information(rss_feed)
				logger.debug(f"[FastAPI] ID:{feed_id},RSS Feed {rss_feed}: db={last_entry}, online={story.chapter_id}")

				if story.chapter_id == last_entry:
					continue

				logger.info(f"[FastAPI] New chapter detected for story ID {feed_id}: {story.story_title}")
				with db.cursor() as cursor:
					cursor.execute (
						"SELECT user_id, feed_name "
						"FROM rss_feed_subscriptions "
						"WHERE rss_feed_id = %s AND active = 1",
						(feed_id,),
					)
					subscribers = cursor.fetchall()

				sent = 0
				failed = 0
				for user_id, feed_name in subscribers:
					try:
						request.app.state.notifier.send(
							title=feed_name or story.story_title,
							body=story.chapter_title,
							link=story.link,
							category="royal-road",
							user_id=user_id,
						)
						send += 1
					except NotificationUnavailableError as e:
						failed = len(subscribers) - sent
						logger.error (f"[FastAPI] Notifications backend unavailable, skipping"
									f"{failed} remaining user(s) for story={story.story_title}")
						break
					except NotificationError as e:
						failed += 1
						logger.error(f"[FastAPI] Failed to send notification to user_id={user_id} for story={story.story_title}"
									f"status={getattr(e, 'status_code',None)}")
				if subscribers and sent == 0:
					results["errors"]+=failed
					logger.error(f"[FastAPI] All notifications failed for Feed ID:{feed_id}, will retry later")
					continue
				with db.cursor() as cursor:
					cursor.execute(
						"UPDATE rss_feeds SET last_entry = %s WHERE id = %s",
						(story.chapter_id, feed_id),
					)
				db.commit()
				logger.debug(f"[FastAPI] Notification sent and database updated for story ID {feed_id}")
				results["new"] += 1

			except Exception as e:
				db.rollback()
				results["errors"] += 1
				logger.error(
					f"[Royalroad] Failed for feed ID {feed_id} ({rss_feed}): {e}",
					exc_info=True,
				)

	if results["errors"]:
		logger.warning(f"[FastAPI] Royalroad check finished with errors: {results}")
		raise HTTPException(status_code=500, detail=results)

	logger.info(f"[FastAPI] Royalroad check complete: {results}")
	return results

async def start_servers():
	logger.info("[Server] Starting main API (port 5000) and metrics server (port 9000)...")
	logger.info(f"[Server] Build commit id={os.getenv("COMMIT_ID","unknown")}")
	config_main = uvicorn.Config(api, host="0.0.0.0", port=5000, log_level=LOG_LEVEL.lower(), log_config=None)
	config_metrics = uvicorn.Config(metrics_api, host="0.0.0.0", port=9000, log_level=LOG_LEVEL.lower(), log_config=None)

	server_main = uvicorn.Server(config_main)
	server_metrics = uvicorn.Server(config_metrics)

	await asyncio.gather(server_main.serve(), server_metrics.serve())
	logger.info("[Server] Both servers have stopped.")

if __name__ == "__main__":
	asyncio.run(start_servers())