"""
Functionality:
- initiate celery app
- collect tasks
- user config changes won't get applied here
  because tasks are initiated at application start
"""

import os

from celery import Celery, Task, shared_task
from home.src.download.queue import PendingList
from home.src.download.subscriptions import (
    SubscriptionHandler,
    SubscriptionScanner,
)
from home.src.download.thumbnails import ThumbFilesystem, ThumbValidator
from home.src.download.yt_dlp_handler import VideoDownloader
from home.src.es.backup import ElasticBackup
from home.src.es.index_setup import ElasitIndexWrap
from home.src.index.channel import YoutubeChannel
from home.src.index.filesystem import Filesystem
from home.src.index.manual import ImportFolderScanner
from home.src.index.reindex import Reindex, ReindexManual, ReindexOutdated
from home.src.ta.config import AppConfig, ReleaseVersion, ScheduleBuilder
from home.src.ta.helper import clear_dl_cache
from home.src.ta.ta_redis import RedisArchivist, RedisQueue
from home.src.ta.task_manager import TaskManager

CONFIG = AppConfig().config
REDIS_HOST = os.environ.get("REDIS_HOST")
REDIS_PORT = os.environ.get("REDIS_PORT") or 6379

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "config.settings")
app = Celery(
    "tasks",
    broker=f"redis://{REDIS_HOST}:{REDIS_PORT}",
    backend=f"redis://{REDIS_HOST}:{REDIS_PORT}",
    result_extended=True,
)
app.config_from_object("django.conf:settings", namespace="ta:")
app.autodiscover_tasks()
app.conf.timezone = os.environ.get("TZ") or "UTC"


class BaseTask(Task):
    """base class to inherit each class from"""

    TASK_CONFIG = {
        "update_subscribed": {
            "title": "Rescan your Subscriptions",
            "group": "message:download:scan",
        },
        "download_pending": {
            "title": "Downloading",
            "group": "message:download:run",
        },
        "extract_download": {
            "title": "Add to download queue",
            "group": "message:download:add",
        },
        "subscribe_to": {
            "title": "Add Subscription",
            "group": "message:download:subscribe",
        },
        "check_reindex": {
            "title": "Reindex Documents",
            "group": "message:settings:reindex",
        },
        "manual_import": {
            "title": "Manual video import",
            "group": "message:settings:import",
        },
        "run_backup": {
            "title": "Index Backup",
            "group": "message:settings:backup",
        },
        "restore_backup": {
            "title": "Restore Backup",
            "group": "message:settings:restore",
        },
        "rescan_filesystem": {
            "title": "Rescan your Filesystem",
            "group": "message:settings:filesystemscan",
        },
        "thumbnail_check": {
            "title": "Check your Thumbnails",
            "group": "message:settings:thumbnailcheck",
        },
        "resync_thumbs": {
            "title": "Sync Thumbnails to Media Files",
            "group": "message:settings:thumbnailsync",
        },
        "index_playlists": {
            "title": "Index Channel Playlist",
            "group": "message:channel:indexplaylist",
        },
    }

    def on_failure(self, exc, task_id, args, kwargs, einfo):
        """callback for task failure"""
        print(f"{task_id} Failed callback")

    def on_success(self, retval, task_id, args, kwargs):
        """callback task completed successfully"""
        print(f"{task_id} success callback")
        message, key = self._build_message()
        message.update({"messages": ["Task completed successfully"]})
        RedisArchivist().set_message(key, message, expire=5)

    def before_start(self, task_id, args, kwargs):
        """callback before initiating task"""
        print(f"{self.name} create callback")
        message, key = self._build_message()
        message.update({"messages": ["New task received."]})
        RedisArchivist().set_message(key, message)

    def send_progress(self, message_lines, progress=False, title=False):
        """send progress message"""
        message, key = self._build_message()
        message.update(
            {
                "messages": message_lines,
                "progress": progress,
            }
        )
        if title:
            message["title"] = title

        RedisArchivist().set_message(key, message)

    def _build_message(self, level="info"):
        """build message dict"""
        task_id = self.request.id
        config = self.TASK_CONFIG.get(self.name)
        message = {
            "status": config.get("group"),
            "title": config.get("title"),
            "level": level,
            "id": task_id,
        }
        key = f"{config.get('group')}:{task_id.split('-')[0]}"
        return message, key


@shared_task(name="update_subscribed", bind=True, base=BaseTask)
def update_subscribed(self):
    """look for missing videos and add to pending"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] rescan already running")
        message = {
            "status": "message:rescan",
            "level": "error",
            "title": "Rescanning channels and playlists.",
            "message": "Rescan already in progress.",
        }
        RedisArchivist().set_message("message:rescan", message, expire=True)
        return

    manager.init(self)
    missing_videos = SubscriptionScanner(task=self).scan()
    if missing_videos:
        print(missing_videos)
        extrac_dl.delay(missing_videos)


@shared_task(name="download_pending", bind=True, base=BaseTask)
def download_pending(self, from_queue=True):
    """download latest pending videos"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] download queue already running")
        return

    manager.init(self)
    downloader = VideoDownloader(task=self)
    if from_queue:
        downloader.add_pending()
    downloader.run_queue()


@shared_task(name="extract_download", bind=True, base=BaseTask)
def extrac_dl(self, youtube_ids):
    """parse list passed and add to pending"""
    pending_handler = PendingList(youtube_ids=youtube_ids, task=self)
    pending_handler.parse_url_list()
    pending_handler.add_to_pending()


@shared_task(bind=True, name="check_reindex", base=BaseTask)
def check_reindex(self, data=False, extract_videos=False):
    """run the reindex main command"""
    if data:
        # started from frontend through API
        print(f"[task][{self.name}] reindex {data}")
        self.send_progress("Add items to the reindex Queue.")
        ReindexManual(extract_videos=extract_videos).extract_data(data)

    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] reindex queue is already running")
        return

    manager.init(self)
    if not data:
        # started from scheduler
        print(f"[task][{self.name}] reindex outdated documents")
        self.send_progress("Add outdated documents to the reindex Queue.")
        ReindexOutdated().add_outdated()

    Reindex(task=self).reindex_all()


@shared_task(bind=True, name="manual_import", base=BaseTask)
def run_manual_import(self):
    """called from settings page, to go through import folder"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] manual import is already running")
        return

    manager.init(self)
    ImportFolderScanner(task=self).scan()


@shared_task(bind=True, name="run_backup", base=BaseTask)
def run_backup(self, reason="auto"):
    """called from settings page, dump backup to zip file"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] backup is already running")
        return

    manager.init(self)
    ElasticBackup(reason=reason, task=self).backup_all_indexes()


@shared_task(bind=True, name="restore_backup", base=BaseTask)
def run_restore_backup(self, filename):
    """called from settings page, dump backup to zip file"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] restore is already running")
        return

    manager.init(self)
    self.send_progress(["Reset your Index"])
    ElasitIndexWrap().reset()
    ElasticBackup(task=self).restore(filename)
    print("index restore finished")


@shared_task(name="kill_download")
def kill_dl(task_id):
    """kill download worker task by ID"""
    if task_id:
        app.control.revoke(task_id, terminate=True)

    _ = RedisArchivist().del_message("dl_queue_id")
    RedisQueue(queue_name="dl_queue").clear()

    _ = clear_dl_cache(CONFIG)

    # notify
    mess_dict = {
        "status": "message:download",
        "level": "error",
        "title": "Canceling download process",
        "message": "Canceling download queue now.",
    }
    RedisArchivist().set_message("message:download", mess_dict, expire=True)


@shared_task(bind=True, name="rescan_filesystem", base=BaseTask)
def rescan_filesystem(self):
    """check the media folder for mismatches"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] filesystem rescan already running")
        return

    manager.init(self)
    Filesystem(task=self).process()
    ThumbValidator(task=self).validate()


@shared_task(bind=True, name="thumbnail_check", base=BaseTask)
def thumbnail_check(self):
    """validate thumbnails"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] thumbnail check is already running")
        return

    manager.init(self)
    ThumbValidator(task=self).validate()


@shared_task(bind=True, name="resync_thumbs", base=BaseTask)
def re_sync_thumbs(self):
    """sync thumbnails to mediafiles"""
    manager = TaskManager()
    if manager.is_pending(self):
        print(f"[task][{self.name}] thumb re-embed is already running")
        return

    manager.init(self)
    ThumbFilesystem(task=self).embed()


@shared_task(name="subscribe_to")
def subscribe_to(url_str):
    """take a list of urls to subscribe to"""
    SubscriptionHandler(url_str).subscribe()


@shared_task(bind=True, name="index_playlists", base=BaseTask)
def index_channel_playlists(self, channel_id):
    """add all playlists of channel to index"""
    channel = YoutubeChannel(channel_id, task=self)
    channel.index_channel_playlists()


@shared_task(name="version_check")
def version_check():
    """check for new updates"""
    ReleaseVersion().check()


# start schedule here
app.conf.beat_schedule = ScheduleBuilder().build_schedule()