Dispatcharr/apps/m3u/tasks.py

# apps/m3u/tasks.py
import logging
import re
import requests
import os
import gc
import gzip, zipfile
from celery.app.control import Inspect
from celery.result import AsyncResult
from celery import shared_task, current_app, group
from django.conf import settings
from django.core.cache import cache
from django.db import transaction
from .models import M3UAccount
from apps.channels.models import Stream, ChannelGroup, ChannelGroupM3UAccount
from asgiref.sync import async_to_sync
from channels.layers import get_channel_layer
from django.utils import timezone
import time
import json
from core.utils import (
    RedisClient,
    acquire_task_lock,
    release_task_lock,
    natural_sort_key,
)
from core.models import CoreSettings, UserAgent
from asgiref.sync import async_to_sync
from core.xtream_codes import Client as XCClient
from core.utils import send_websocket_update

logger = logging.getLogger(__name__)

BATCH_SIZE = 1000
m3u_dir = os.path.join(settings.MEDIA_ROOT, "cached_m3u")


def fetch_m3u_lines(account, use_cache=False):
    os.makedirs(m3u_dir, exist_ok=True)
    file_path = os.path.join(m3u_dir, f"{account.id}.m3u")

    """Fetch M3U file lines efficiently."""
    if account.server_url:
        if not use_cache or not os.path.exists(file_path):
            try:
                # Try to get account-specific user agent first
                user_agent_obj = account.get_user_agent()
                user_agent = (
                    user_agent_obj.user_agent
                    if user_agent_obj
                    else "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36"
                )

                logger.debug(
                    f"Using user agent: {user_agent} for M3U account: {account.name}"
                )
                headers = {"User-Agent": user_agent}
                logger.info(f"Fetching from URL {account.server_url}")

                # Set account status to FETCHING before starting download
                account.status = M3UAccount.Status.FETCHING
                account.last_message = "Starting download..."
                account.save(update_fields=["status", "last_message"])

                response = requests.get(
                    account.server_url, headers=headers, stream=True
                )
                response.raise_for_status()

                total_size = int(response.headers.get("Content-Length", 0))
                downloaded = 0
                start_time = time.time()
                last_update_time = start_time
                progress = 0

                with open(file_path, "wb") as file:
                    send_m3u_update(account.id, "downloading", 0)
                    for chunk in response.iter_content(chunk_size=8192):
                        if chunk:
                            file.write(chunk)

                            downloaded += len(chunk)
                            elapsed_time = time.time() - start_time

                            # Calculate download speed in KB/s
                            speed = downloaded / elapsed_time / 1024  # in KB/s

                            # Calculate progress percentage
                            if total_size and total_size > 0:
                                progress = (downloaded / total_size) * 100

                            # Time remaining (in seconds)
                            time_remaining = (
                                (total_size - downloaded) / (speed * 1024)
                                if speed > 0
                                else 0
                            )

                            current_time = time.time()
                            if current_time - last_update_time >= 0.5:
                                last_update_time = current_time
                                if progress > 0:
                                    # Update the account's last_message with detailed progress info
                                    progress_msg = f"Downloading: {progress:.1f}% - {speed:.1f} KB/s - {time_remaining:.1f}s remaining"
                                    account.last_message = progress_msg
                                    account.save(update_fields=["last_message"])

                                    send_m3u_update(
                                        account.id,
                                        "downloading",
                                        progress,
                                        speed=speed,
                                        elapsed_time=elapsed_time,
                                        time_remaining=time_remaining,
                                        message=progress_msg,
                                    )

                # Final update with 100% progress
                final_msg = f"Download complete. Size: {total_size/1024/1024:.2f} MB, Time: {time.time() - start_time:.1f}s"
                account.last_message = final_msg
                account.save(update_fields=["last_message"])
                send_m3u_update(account.id, "downloading", 100, message=final_msg)
            except Exception as e:
                logger.error(f"Error fetching M3U from URL {account.server_url}: {e}")
                # Update account status and send error notification
                account.status = M3UAccount.Status.ERROR
                account.last_message = f"Error downloading M3U file: {str(e)}"
                account.save(update_fields=["status", "last_message"])
                send_m3u_update(
                    account.id,
                    "downloading",
                    100,
                    status="error",
                    error=f"Error downloading M3U file: {str(e)}",
                )
                return [], False  # Return empty list and False for success

        # Check if the file exists and is not empty
        if not os.path.exists(file_path) or os.path.getsize(file_path) == 0:
            error_msg = f"M3U file not found or empty: {file_path}"
            logger.error(error_msg)
            account.status = M3UAccount.Status.ERROR
            account.last_message = error_msg
            account.save(update_fields=["status", "last_message"])
            send_m3u_update(
                account.id, "downloading", 100, status="error", error=error_msg
            )
            return [], False  # Return empty list and False for success

        try:
            with open(file_path, "r", encoding="utf-8") as f:
                return f.readlines(), True
        except Exception as e:
            error_msg = f"Error reading M3U file: {str(e)}"
            logger.error(error_msg)
            account.status = M3UAccount.Status.ERROR
            account.last_message = error_msg
            account.save(update_fields=["status", "last_message"])
            send_m3u_update(
                account.id, "downloading", 100, status="error", error=error_msg
            )
            return [], False

    elif account.file_path:
        try:
            if account.file_path.endswith(".gz"):
                with gzip.open(account.file_path, "rt", encoding="utf-8") as f:
                    return f.readlines(), True

            elif account.file_path.endswith(".zip"):
                with zipfile.ZipFile(account.file_path, "r") as zip_file:
                    for name in zip_file.namelist():
                        if name.endswith(".m3u"):
                            with zip_file.open(name) as f:
                                return [
                                    line.decode("utf-8") for line in f.readlines()
                                ], True

                    error_msg = (
                        f"No .m3u file found in ZIP archive: {account.file_path}"
                    )
                    logger.warning(error_msg)
                    account.status = M3UAccount.Status.ERROR
                    account.last_message = error_msg
                    account.save(update_fields=["status", "last_message"])
                    send_m3u_update(
                        account.id, "downloading", 100, status="error", error=error_msg
                    )
                    return [], False

            else:
                with open(account.file_path, "r", encoding="utf-8") as f:
                    return f.readlines(), True

        except (IOError, OSError, zipfile.BadZipFile, gzip.BadGzipFile) as e:
            error_msg = f"Error opening file {account.file_path}: {e}"
            logger.error(error_msg)
            account.status = M3UAccount.Status.ERROR
            account.last_message = error_msg
            account.save(update_fields=["status", "last_message"])
            send_m3u_update(
                account.id, "downloading", 100, status="error", error=error_msg
            )
            return [], False

    # Neither server_url nor uploaded_file is available
    error_msg = "No M3U source available (missing URL and file)"
    logger.error(error_msg)
    account.status = M3UAccount.Status.ERROR
    account.last_message = error_msg
    account.save(update_fields=["status", "last_message"])
    send_m3u_update(account.id, "downloading", 100, status="error", error=error_msg)
    return [], False


def get_case_insensitive_attr(attributes, key, default=""):
    """Get attribute value using case-insensitive key lookup."""
    for attr_key, attr_value in attributes.items():
        if attr_key.lower() == key.lower():
            return attr_value
    return default


def parse_extinf_line(line: str) -> dict:
    """
    Parse an EXTINF line from an M3U file.
    This function removes the "#EXTINF:" prefix, then splits the remaining
    string on the first comma that is not enclosed in quotes.

    Returns a dictionary with:
      - 'attributes': a dict of attribute key/value pairs (e.g. tvg-id, tvg-logo, group-title)
      - 'display_name': the text after the comma (the fallback display name)
      - 'name': the value from tvg-name (if present) or the display name otherwise.
    """
    if not line.startswith("#EXTINF:"):
        return None
    content = line[len("#EXTINF:") :].strip()
    # Split on the first comma that is not inside quotes.
    parts = re.split(r',(?=(?:[^"]*"[^"]*")*[^"]*$)', content, maxsplit=1)
    if len(parts) != 2:
        return None
    attributes_part, display_name = parts[0], parts[1].strip()
    attrs = dict(re.findall(r'([^\s]+)=["\']([^"\']+)["\']', attributes_part))
    # Use tvg-name attribute if available; otherwise, use the display name.
    name = get_case_insensitive_attr(attrs, "tvg-name", display_name)
    return {"attributes": attrs, "display_name": display_name, "name": name}


@shared_task
def refresh_m3u_accounts():
    """Queue background parse for all active M3UAccounts."""
    active_accounts = M3UAccount.objects.filter(is_active=True)
    count = 0
    for account in active_accounts:
        refresh_single_m3u_account.delay(account.id)
        count += 1

    msg = f"Queued M3U refresh for {count} active account(s)."
    logger.info(msg)
    return msg


def check_field_lengths(streams_to_create):
    for stream in streams_to_create:
        for field, value in stream.__dict__.items():
            if isinstance(value, str) and len(value) > 255:
                print(f"{field} --- {value}")

        print("")
        print("")


@shared_task
def process_groups(account, groups):
    existing_groups = {
        group.name: group
        for group in ChannelGroup.objects.filter(name__in=groups.keys())
    }
    logger.info(f"Currently {len(existing_groups)} existing groups")

    group_objs = []
    groups_to_create = []
    for group_name, custom_props in groups.items():
        logger.debug(f"Handling group for M3U account {account.id}: {group_name}")

        if group_name not in existing_groups:
            groups_to_create.append(
                ChannelGroup(
                    name=group_name,
                )
            )
        else:
            group_objs.append(existing_groups[group_name])

    if groups_to_create:
        logger.debug(f"Creating {len(groups_to_create)} groups")
        created = ChannelGroup.bulk_create_and_fetch(groups_to_create)
        logger.debug(f"Created {len(created)} groups")
        group_objs.extend(created)

    relations = []
    for group in group_objs:
        # Ensure we include the xc_id in the custom_properties
        custom_props = groups.get(group.name, {})
        relations.append(
            ChannelGroupM3UAccount(
                channel_group=group,
                m3u_account=account,
                custom_properties=json.dumps(custom_props),
                enabled=True,  # Default to enabled
            )
        )

    ChannelGroupM3UAccount.objects.bulk_create(relations, ignore_conflicts=True)


@shared_task
def process_xc_category(account_id, batch, groups, hash_keys):
    account = M3UAccount.objects.get(id=account_id)

    streams_to_create = []
    streams_to_update = []
    stream_hashes = {}

    try:
        with XCClient(
            account.server_url,
            account.username,
            account.password,
            account.get_user_agent(),
        ) as xc_client:
            # Log the batch details to help with debugging
            logger.debug(f"Processing XC batch: {batch}")

            for group_name, props in batch.items():
                # Check if we have a valid xc_id for this group
                if "xc_id" not in props:
                    logger.error(
                        f"Missing xc_id for group {group_name} in batch {batch}"
                    )
                    continue

                # Get actual group ID from the mapping
                group_id = groups.get(group_name)
                if not group_id:
                    logger.error(f"Group {group_name} not found in enabled groups")
                    continue

                try:
                    logger.debug(
                        f"Fetching streams for XC category: {group_name} (ID: {props['xc_id']})"
                    )
                    streams = xc_client.get_live_category_streams(props["xc_id"])

                    if not streams:
                        logger.warning(
                            f"No streams found for XC category {group_name} (ID: {props['xc_id']})"
                        )
                        continue

                    logger.debug(
                        f"Found {len(streams)} streams for category {group_name}"
                    )

                    for stream in streams:
                        name = stream["name"]
                        url = xc_client.get_stream_url(stream["stream_id"])
                        tvg_id = stream.get("epg_channel_id", "")
                        tvg_logo = stream.get("stream_icon", "")
                        group_title = group_name

                        stream_hash = Stream.generate_hash_key(
                            name, url, tvg_id, hash_keys
                        )
                        stream_props = {
                            "name": name,
                            "url": url,
                            "logo_url": tvg_logo,
                            "tvg_id": tvg_id,
                            "m3u_account": account,
                            "channel_group_id": int(group_id),
                            "stream_hash": stream_hash,
                            "custom_properties": json.dumps(stream),
                        }

                        if stream_hash not in stream_hashes:
                            stream_hashes[stream_hash] = stream_props
                except Exception as e:
                    logger.error(
                        f"Error processing XC category {group_name} (ID: {props['xc_id']}): {str(e)}"
                    )
                    continue

        # Process all found streams
        existing_streams = {
            s.stream_hash: s
            for s in Stream.objects.filter(stream_hash__in=stream_hashes.keys())
        }

        for stream_hash, stream_props in stream_hashes.items():
            if stream_hash in existing_streams:
                obj = existing_streams[stream_hash]
                existing_attr = {
                    field.name: getattr(obj, field.name)
                    for field in Stream._meta.fields
                    if field != "channel_group_id"
                }
                changed = any(
                    existing_attr[key] != value
                    for key, value in stream_props.items()
                    if key != "channel_group_id"
                )

                if changed:
                    for key, value in stream_props.items():
                        setattr(obj, key, value)
                    obj.last_seen = timezone.now()
                    obj.updated_at = (
                        timezone.now()
                    )  # Update timestamp only for changed streams
                    streams_to_update.append(obj)
                    del existing_streams[stream_hash]
                else:
                    # Always update last_seen, even if nothing else changed
                    obj.last_seen = timezone.now()
                    # Don't update updated_at for unchanged streams
                    streams_to_update.append(obj)
                    existing_streams[stream_hash] = obj
            else:
                stream_props["last_seen"] = timezone.now()
                stream_props["updated_at"] = (
                    timezone.now()
                )  # Set initial updated_at for new streams
                streams_to_create.append(Stream(**stream_props))

        try:
            with transaction.atomic():
                if streams_to_create:
                    Stream.objects.bulk_create(streams_to_create, ignore_conflicts=True)
                if streams_to_update:
                    # We need to split the bulk update to correctly handle updated_at
                    # First, get the subset of streams that have content changes
                    changed_streams = [
                        s
                        for s in streams_to_update
                        if hasattr(s, "updated_at") and s.updated_at
                    ]
                    unchanged_streams = [
                        s
                        for s in streams_to_update
                        if not hasattr(s, "updated_at") or not s.updated_at
                    ]

                    # Update changed streams with all fields including updated_at
                    if changed_streams:
                        Stream.objects.bulk_update(
                            changed_streams,
                            {
                                key
                                for key in stream_props.keys()
                                if key not in ["m3u_account", "stream_hash"]
                                and key not in hash_keys
                            }
                            | {"last_seen", "updated_at"},
                        )

                    # Update unchanged streams with only last_seen
                    if unchanged_streams:
                        Stream.objects.bulk_update(unchanged_streams, ["last_seen"])

                if len(existing_streams.keys()) > 0:
                    Stream.objects.bulk_update(existing_streams.values(), ["last_seen"])
        except Exception as e:
            logger.error(f"Bulk create failed for XC streams: {str(e)}")

        retval = f"Batch processed: {len(streams_to_create)} created, {len(streams_to_update)} updated."

    except Exception as e:
        logger.error(f"XC category processing error: {str(e)}")
        retval = f"Error processing XC batch: {str(e)}"

    # Aggressive garbage collection
    del streams_to_create, streams_to_update, stream_hashes, existing_streams
    gc.collect()

    return retval


@shared_task
def process_m3u_batch(account_id, batch, groups, hash_keys):
    """Processes a batch of M3U streams using bulk operations."""
    account = M3UAccount.objects.get(id=account_id)

    compiled_filters = [
        (
            re.compile(
                f.regex_pattern,
                (
                    re.IGNORECASE
                    if json.loads(f.custom_properties or "{}").get(
                        "case_sensitive", True
                    )
                    == False
                    else 0
                ),
            ),
            f,
        )
        for f in account.filters.order_by("order")
    ]

    streams_to_create = []
    streams_to_update = []
    stream_hashes = {}

    logger.debug(f"Processing batch of {len(batch)} for M3U account {account_id}")
    for stream_info in batch:
        try:
            name, url = stream_info["name"], stream_info["url"]
            tvg_id, tvg_logo = get_case_insensitive_attr(
                stream_info["attributes"], "tvg-id", ""
            ), get_case_insensitive_attr(stream_info["attributes"], "tvg-logo", "")
            group_title = get_case_insensitive_attr(
                stream_info["attributes"], "group-title", "Default Group"
            )

            include = True
            for pattern, filter in compiled_filters:
                logger.debug(f"Checking filter patterh {pattern}")
                target = name
                if filter.filter_type == "url":
                    target = url
                elif filter.filter_type == "group":
                    target = group_title

                if pattern.search(target or ""):
                    logger.debug(
                        f"Stream {name} - {url} matches filter pattern {filter.regex_pattern}"
                    )
                    include = not filter.exclude
                    break

            if not include:
                logger.debug(f"Stream excluded by filter, skipping.")
                continue

            # Filter out disabled groups for this account
            if group_title not in groups:
                logger.debug(
                    f"Skipping stream in disabled or excluded group: {group_title}"
                )
                continue

            stream_hash = Stream.generate_hash_key(name, url, tvg_id, hash_keys)
            stream_props = {
                "name": name,
                "url": url,
                "logo_url": tvg_logo,
                "tvg_id": tvg_id,
                "m3u_account": account,
                "channel_group_id": int(groups.get(group_title)),
                "stream_hash": stream_hash,
                "custom_properties": json.dumps(stream_info["attributes"]),
            }

            if stream_hash not in stream_hashes:
                stream_hashes[stream_hash] = stream_props
        except Exception as e:
            logger.error(f"Failed to process stream {name}: {e}")
            logger.error(json.dumps(stream_info))

    existing_streams = {
        s.stream_hash: s
        for s in Stream.objects.filter(stream_hash__in=stream_hashes.keys())
    }

    for stream_hash, stream_props in stream_hashes.items():
        if stream_hash in existing_streams:
            obj = existing_streams[stream_hash]
            existing_attr = {
                field.name: getattr(obj, field.name)
                for field in Stream._meta.fields
                if field != "channel_group_id"
            }
            changed = any(
                existing_attr[key] != value
                for key, value in stream_props.items()
                if key != "channel_group_id"
            )

            if changed:
                for key, value in stream_props.items():
                    setattr(obj, key, value)
                obj.last_seen = timezone.now()
                obj.updated_at = (
                    timezone.now()
                )  # Update timestamp only for changed streams
                streams_to_update.append(obj)
                del existing_streams[stream_hash]
            else:
                # Always update last_seen, even if nothing else changed
                obj.last_seen = timezone.now()
                # Don't update updated_at for unchanged streams
                streams_to_update.append(obj)
                existing_streams[stream_hash] = obj
        else:
            stream_props["last_seen"] = timezone.now()
            stream_props["updated_at"] = (
                timezone.now()
            )  # Set initial updated_at for new streams
            streams_to_create.append(Stream(**stream_props))

    try:
        with transaction.atomic():
            if streams_to_create:
                Stream.objects.bulk_create(streams_to_create, ignore_conflicts=True)
            if streams_to_update:
                # We need to split the bulk update to correctly handle updated_at
                # First, get the subset of streams that have content changes
                changed_streams = [
                    s
                    for s in streams_to_update
                    if hasattr(s, "updated_at") and s.updated_at
                ]
                unchanged_streams = [
                    s
                    for s in streams_to_update
                    if not hasattr(s, "updated_at") or not s.updated_at
                ]

                # Update changed streams with all fields including updated_at
                if changed_streams:
                    Stream.objects.bulk_update(
                        changed_streams,
                        {
                            key
                            for key in stream_props.keys()
                            if key not in ["m3u_account", "stream_hash"]
                            and key not in hash_keys
                        }
                        | {"last_seen", "updated_at"},
                    )

                # Update unchanged streams with only last_seen
                if unchanged_streams:
                    Stream.objects.bulk_update(unchanged_streams, ["last_seen"])

            if len(existing_streams.keys()) > 0:
                Stream.objects.bulk_update(existing_streams.values(), ["last_seen"])
    except Exception as e:
        logger.error(f"Bulk create failed: {str(e)}")

    retval = f"M3U account: {account_id}, Batch processed: {len(streams_to_create)} created, {len(streams_to_update)} updated."

    # Aggressive garbage collection
    # del streams_to_create, streams_to_update, stream_hashes, existing_streams
    # from core.utils import cleanup_memory
    # cleanup_memory(log_usage=True, force_collection=True)

    return retval


def cleanup_streams(account_id, scan_start_time=timezone.now):
    account = M3UAccount.objects.get(id=account_id, is_active=True)
    existing_groups = ChannelGroup.objects.filter(
        m3u_account__m3u_account=account,
        m3u_account__enabled=True,
    ).values_list("id", flat=True)
    logger.info(
        f"Found {len(existing_groups)} active groups for M3U account {account_id}"
    )

    # Calculate cutoff date for stale streams
    stale_cutoff = scan_start_time - timezone.timedelta(days=account.stale_stream_days)
    logger.info(
        f"Removing streams not seen since {stale_cutoff} for M3U account {account_id}"
    )

    # Delete streams that are not in active groups
    streams_to_delete = Stream.objects.filter(m3u_account=account).exclude(
        channel_group__in=existing_groups
    )

    # Also delete streams that haven't been seen for longer than stale_stream_days
    stale_streams = Stream.objects.filter(
        m3u_account=account, last_seen__lt=stale_cutoff
    )

    deleted_count = streams_to_delete.count()
    stale_count = stale_streams.count()

    streams_to_delete.delete()
    stale_streams.delete()

    total_deleted = deleted_count + stale_count
    logger.info(
        f"Cleanup for M3U account {account_id} complete: {deleted_count} streams removed due to group filter, {stale_count} removed as stale"
    )

    # Return the total count of deleted streams
    return total_deleted


@shared_task
def refresh_m3u_groups(account_id, use_cache=False, full_refresh=False):
    if not acquire_task_lock("refresh_m3u_account_groups", account_id):
        return f"Task already running for account_id={account_id}.", None

    try:
        account = M3UAccount.objects.get(id=account_id, is_active=True)
    except M3UAccount.DoesNotExist:
        release_task_lock("refresh_m3u_account_groups", account_id)
        return f"M3UAccount with ID={account_id} not found or inactive.", None

    extinf_data = []
    groups = {"Default Group": {}}

    if account.account_type == M3UAccount.Types.XC:
        # Log detailed information about the account
        logger.info(
            f"Processing XC account {account_id} with URL: {account.server_url}"
        )
        logger.debug(
            f"Username: {account.username}, Has password: {'Yes' if account.password else 'No'}"
        )

        # Validate required fields
        if not account.server_url:
            error_msg = "Missing server URL for Xtream Codes account"
            logger.error(error_msg)
            account.status = M3UAccount.Status.ERROR
            account.last_message = error_msg
            account.save(update_fields=["status", "last_message"])
            send_m3u_update(
                account_id, "processing_groups", 100, status="error", error=error_msg
            )
            release_task_lock("refresh_m3u_account_groups", account_id)
            return error_msg, None

        if not account.username or not account.password:
            error_msg = "Missing username or password for Xtream Codes account"
            logger.error(error_msg)
            account.status = M3UAccount.Status.ERROR
            account.last_message = error_msg
            account.save(update_fields=["status", "last_message"])
            send_m3u_update(
                account_id, "processing_groups", 100, status="error", error=error_msg
            )
            release_task_lock("refresh_m3u_account_groups", account_id)
            return error_msg, None

        try:
            # Ensure server URL is properly formatted
            server_url = account.server_url.rstrip("/")
            if not (
                server_url.startswith("http://") or server_url.startswith("https://")
            ):
                server_url = f"http://{server_url}"

            # User agent handling - completely rewritten
            try:
                # Debug the user agent issue
                logger.debug(f"Getting user agent for account {account.id}")

                # Use a hardcoded user agent string to avoid any issues with object structure
                user_agent_string = (
                    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36"
                )

                try:
                    # Try to get the user agent directly from the database
                    if account.user_agent_id:
                        ua_obj = UserAgent.objects.get(id=account.user_agent_id)
                        if (
                            ua_obj
                            and hasattr(ua_obj, "user_agent")
                            and ua_obj.user_agent
                        ):
                            user_agent_string = ua_obj.user_agent
                            logger.debug(
                                f"Using user agent from account: {user_agent_string}"
                            )
                    else:
                        # Get default user agent from CoreSettings
                        default_ua_id = CoreSettings.get_default_user_agent_id()
                        logger.debug(
                            f"Default user agent ID from settings: {default_ua_id}"
                        )
                        if default_ua_id:
                            ua_obj = UserAgent.objects.get(id=default_ua_id)
                            if (
                                ua_obj
                                and hasattr(ua_obj, "user_agent")
                                and ua_obj.user_agent
                            ):
                                user_agent_string = ua_obj.user_agent
                                logger.debug(
                                    f"Using default user agent: {user_agent_string}"
                                )
                except Exception as e:
                    logger.warning(
                        f"Error getting user agent, using fallback: {str(e)}"
                    )

                logger.debug(f"Final user agent string: {user_agent_string}")
            except Exception as e:
                user_agent_string = (
                    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36"
                )
                logger.warning(
                    f"Exception in user agent handling, using fallback: {str(e)}"
                )

            logger.info(
                f"Creating XCClient with URL: {server_url}, Username: {account.username}, User-Agent: {user_agent_string}"
            )

            # Create XCClient with explicit error handling
            try:
                with XCClient(
                    server_url, account.username, account.password, user_agent_string
                ) as xc_client:
                    logger.info(f"XCClient instance created successfully")

                    # Authenticate with detailed error handling
                    try:
                        logger.debug(f"Authenticating with XC server {server_url}")
                        auth_result = xc_client.authenticate()
                        logger.debug(f"Authentication response: {auth_result}")
                    except Exception as e:
                        error_msg = f"Failed to authenticate with XC server: {str(e)}"
                        logger.error(error_msg)
                        account.status = M3UAccount.Status.ERROR
                        account.last_message = error_msg
                        account.save(update_fields=["status", "last_message"])
                        send_m3u_update(
                            account_id,
                            "processing_groups",
                            100,
                            status="error",
                            error=error_msg,
                        )
                        release_task_lock("refresh_m3u_account_groups", account_id)
                        return error_msg, None

                    # Get categories with detailed error handling
                    try:
                        logger.info(f"Getting live categories from XC server")
                        xc_categories = xc_client.get_live_categories()
                        logger.info(
                            f"Found {len(xc_categories)} categories: {xc_categories}"
                        )

                        # Validate response
                        if not isinstance(xc_categories, list):
                            error_msg = (
                                f"Unexpected response from XC server: {xc_categories}"
                            )
                            logger.error(error_msg)
                            account.status = M3UAccount.Status.ERROR
                            account.last_message = error_msg
                            account.save(update_fields=["status", "last_message"])
                            send_m3u_update(
                                account_id,
                                "processing_groups",
                                100,
                                status="error",
                                error=error_msg,
                            )
                            release_task_lock("refresh_m3u_account_groups", account_id)
                            return error_msg, None

                        if len(xc_categories) == 0:
                            logger.warning("No categories found in XC server response")

                        for category in xc_categories:
                            cat_name = category.get("category_name", "Unknown Category")
                            cat_id = category.get("category_id", "0")
                            logger.info(f"Adding category: {cat_name} (ID: {cat_id})")
                            groups[cat_name] = {
                                "xc_id": cat_id,
                            }
                    except Exception as e:
                        error_msg = f"Failed to get categories from XC server: {str(e)}"
                        logger.error(error_msg)
                        account.status = M3UAccount.Status.ERROR
                        account.last_message = error_msg
                        account.save(update_fields=["status", "last_message"])
                        send_m3u_update(
                            account_id,
                            "processing_groups",
                            100,
                            status="error",
                            error=error_msg,
                        )
                        release_task_lock("refresh_m3u_account_groups", account_id)
                        return error_msg, None

            except Exception as e:
                error_msg = f"Failed to create XC Client: {str(e)}"
                logger.error(error_msg)
                account.status = M3UAccount.Status.ERROR
                account.last_message = error_msg
                account.save(update_fields=["status", "last_message"])
                send_m3u_update(
                    account_id,
                    "processing_groups",
                    100,
                    status="error",
                    error=error_msg,
                )
                release_task_lock("refresh_m3u_account_groups", account_id)
                return error_msg, None
        except Exception as e:
            error_msg = f"Unexpected error occurred in XC Client: {str(e)}"
            logger.error(error_msg)
            account.status = M3UAccount.Status.ERROR
            account.last_message = error_msg
            account.save(update_fields=["status", "last_message"])
            send_m3u_update(
                account_id, "processing_groups", 100, status="error", error=error_msg
            )
            release_task_lock("refresh_m3u_account_groups", account_id)
            return error_msg, None
    else:
        # Here's the key change - use the success flag from fetch_m3u_lines
        lines, success = fetch_m3u_lines(account, use_cache)
        if not success:
            # If fetch failed, don't continue processing
            release_task_lock("refresh_m3u_account_groups", account_id)
            return f"Failed to fetch M3U data for account_id={account_id}.", None

        # Log basic file structure for debugging
        logger.debug(f"Processing {len(lines)} lines from M3U file")

        line_count = 0
        extinf_count = 0
        url_count = 0
        valid_stream_count = 0
        problematic_lines = []

        for line_index, line in enumerate(lines):
            line_count += 1
            line = line.strip()

            if line.startswith("#EXTINF"):
                extinf_count += 1
                parsed = parse_extinf_line(line)
                if parsed:
                    group_title_attr = get_case_insensitive_attr(
                        parsed["attributes"], "group-title", ""
                    )
                    if group_title_attr:
                        group_name = group_title_attr
                        # Log new groups as they're discovered
                        if group_name not in groups:
                            logger.debug(
                                f"Found new group for M3U account {account_id}: '{group_name}'"
                            )
                        groups[group_name] = {}

                    extinf_data.append(parsed)
                else:
                    # Log problematic EXTINF lines
                    logger.warning(
                        f"Failed to parse EXTINF at line {line_index+1}: {line[:200]}"
                    )
                    problematic_lines.append((line_index + 1, line[:200]))

            elif extinf_data and line.startswith("http"):
                url_count += 1
                # Associate URL with the last EXTINF line
                extinf_data[-1]["url"] = line
                valid_stream_count += 1

                # Periodically log progress for large files
                if valid_stream_count % 1000 == 0:
                    logger.debug(
                        f"Processed {valid_stream_count} valid streams so far for M3U account: {account_id}"
                    )

        # Log summary statistics
        logger.info(
            f"M3U parsing complete - Lines: {line_count}, EXTINF: {extinf_count}, URLs: {url_count}, Valid streams: {valid_stream_count}"
        )

        if problematic_lines:
            logger.warning(
                f"Found {len(problematic_lines)} problematic lines during parsing"
            )
            for i, (line_num, content) in enumerate(
                problematic_lines[:10]
            ):  # Log max 10 examples
                logger.warning(f"Problematic line #{i+1} at line {line_num}: {content}")
            if len(problematic_lines) > 10:
                logger.warning(
                    f"... and {len(problematic_lines) - 10} more problematic lines"
                )

        # Log group statistics
        logger.info(
            f"Found {len(groups)} groups in M3U file: {', '.join(list(groups.keys())[:20])}"
            + ("..." if len(groups) > 20 else "")
        )

        # Cache processed data
        cache_path = os.path.join(m3u_dir, f"{account_id}.json")
        with open(cache_path, "w", encoding="utf-8") as f:
            json.dump(
                {
                    "extinf_data": extinf_data,
                    "groups": groups,
                },
                f,
            )
            logger.debug(f"Cached parsed M3U data to {cache_path}")

    send_m3u_update(account_id, "processing_groups", 0)

    process_groups(account, groups)

    release_task_lock("refresh_m3u_account_groups", account_id)

    if not full_refresh:
        # Use update() instead of save() to avoid triggering signals
        M3UAccount.objects.filter(id=account_id).update(
            status=M3UAccount.Status.PENDING_SETUP,
            last_message="M3U groups loaded. Please select groups or refresh M3U to complete setup.",
        )
        send_m3u_update(
            account_id,
            "processing_groups",
            100,
            status="pending_setup",
            message="M3U groups loaded. Please select groups or refresh M3U to complete setup.",
        )

    return extinf_data, groups


def delete_m3u_refresh_task_by_id(account_id):
    """
    Delete the periodic task associated with an M3U account ID.
    Can be called directly or from the post_delete signal.
    Returns True if a task was found and deleted, False otherwise.
    """
    try:
        task = None
        task_name = f"m3u_account-refresh-{account_id}"

        # Look for task by name
        try:
            from django_celery_beat.models import PeriodicTask, IntervalSchedule

            task = PeriodicTask.objects.get(name=task_name)
            logger.debug(f"Found task by name: {task.id} for M3UAccount {account_id}")
        except PeriodicTask.DoesNotExist:
            logger.warning(f"No PeriodicTask found with name {task_name}")
            return False

        # Now delete the task and its interval
        if task:
            # Store interval info before deleting the task
            interval_id = None
            if hasattr(task, "interval") and task.interval:
                interval_id = task.interval.id

                # Count how many TOTAL tasks use this interval (including this one)
                tasks_with_same_interval = PeriodicTask.objects.filter(
                    interval_id=interval_id
                ).count()
                logger.debug(
                    f"Interval {interval_id} is used by {tasks_with_same_interval} tasks total"
                )

            # Delete the task first
            task_id = task.id
            task.delete()
            logger.debug(f"Successfully deleted periodic task {task_id}")

            # Now check if we should delete the interval
            # We only delete if it was the ONLY task using this interval
            if interval_id and tasks_with_same_interval == 1:
                try:
                    interval = IntervalSchedule.objects.get(id=interval_id)
                    logger.debug(
                        f"Deleting interval schedule {interval_id} (not shared with other tasks)"
                    )
                    interval.delete()
                    logger.debug(f"Successfully deleted interval {interval_id}")
                except IntervalSchedule.DoesNotExist:
                    logger.warning(f"Interval {interval_id} no longer exists")
            elif interval_id:
                logger.debug(
                    f"Not deleting interval {interval_id} as it's shared with {tasks_with_same_interval-1} other tasks"
                )

            return True
        return False
    except Exception as e:
        logger.error(
            f"Error deleting periodic task for M3UAccount {account_id}: {str(e)}",
            exc_info=True,
        )
        return False


@shared_task
def sync_auto_channels(account_id, scan_start_time=None):
    """
    Automatically create/update/delete channels to match streams in groups with auto_channel_sync enabled.
    Preserves existing channel UUIDs to maintain M3U link integrity.
    Called after M3U refresh completes successfully.
    """
    from apps.channels.models import (
        Channel,
        ChannelGroup,
        ChannelGroupM3UAccount,
        Stream,
        ChannelStream,
    )
    from apps.epg.models import EPGData
    from django.utils import timezone

    try:
        account = M3UAccount.objects.get(id=account_id)
        logger.info(f"Starting auto channel sync for M3U account {account.name}")

        # Always use scan_start_time as the cutoff for last_seen
        if scan_start_time is not None:
            if isinstance(scan_start_time, str):
                scan_start_time = timezone.datetime.fromisoformat(scan_start_time)
        else:
            scan_start_time = timezone.now()

        # Get groups with auto sync enabled for this account
        auto_sync_groups = ChannelGroupM3UAccount.objects.filter(
            m3u_account=account, enabled=True, auto_channel_sync=True
        ).select_related("channel_group")

        channels_created = 0
        channels_updated = 0
        channels_deleted = 0

        for group_relation in auto_sync_groups:
            channel_group = group_relation.channel_group
            start_number = group_relation.auto_sync_channel_start or 1.0

            # Get force_dummy_epg, group_override, and regex patterns from group custom_properties
            group_custom_props = {}
            force_dummy_epg = False
            override_group_id = None
            name_regex_pattern = None
            name_replace_pattern = None
            name_match_regex = None
            channel_profile_ids = None
            channel_sort_order = None
            channel_sort_reverse = False
            if group_relation.custom_properties:
                try:
                    group_custom_props = json.loads(group_relation.custom_properties)
                    force_dummy_epg = group_custom_props.get("force_dummy_epg", False)
                    override_group_id = group_custom_props.get("group_override")
                    name_regex_pattern = group_custom_props.get("name_regex_pattern")
                    name_replace_pattern = group_custom_props.get(
                        "name_replace_pattern"
                    )
                    name_match_regex = group_custom_props.get("name_match_regex")
                    channel_profile_ids = group_custom_props.get("channel_profile_ids")
                    channel_sort_order = group_custom_props.get("channel_sort_order")
                    channel_sort_reverse = group_custom_props.get(
                        "channel_sort_reverse", False
                    )
                except Exception:
                    force_dummy_epg = False
                    override_group_id = None
                    name_regex_pattern = None
                    name_replace_pattern = None
                    name_match_regex = None
                    channel_profile_ids = None
                    channel_sort_order = None
                    channel_sort_reverse = False

            # Determine which group to use for created channels
            target_group = channel_group
            if override_group_id:
                try:
                    target_group = ChannelGroup.objects.get(id=override_group_id)
                    logger.info(
                        f"Using override group '{target_group.name}' instead of '{channel_group.name}' for auto-created channels"
                    )
                except ChannelGroup.DoesNotExist:
                    logger.warning(
                        f"Override group with ID {override_group_id} not found, using original group '{channel_group.name}'"
                    )

            logger.info(
                f"Processing auto sync for group: {channel_group.name} (start: {start_number})"
            )

            # Get all current streams in this group for this M3U account, filter out stale streams
            current_streams = Stream.objects.filter(
                m3u_account=account,
                channel_group=channel_group,
                last_seen__gte=scan_start_time,
            )

            # --- FILTER STREAMS BY NAME MATCH REGEX IF SPECIFIED ---
            if name_match_regex:
                try:
                    current_streams = current_streams.filter(
                        name__iregex=name_match_regex
                    )
                except re.error as e:
                    logger.warning(
                        f"Invalid name_match_regex '{name_match_regex}' for group '{channel_group.name}': {e}. Skipping name filter."
                    )

            # --- APPLY CHANNEL SORT ORDER ---
            streams_is_list = False  # Track if we converted to list
            if channel_sort_order and channel_sort_order != "":
                if channel_sort_order == "name":
                    # Use natural sorting for names to handle numbers correctly
                    current_streams = list(current_streams)
                    current_streams.sort(
                        key=lambda stream: natural_sort_key(stream.name),
                        reverse=channel_sort_reverse,
                    )
                    streams_is_list = True
                elif channel_sort_order == "tvg_id":
                    order_prefix = "-" if channel_sort_reverse else ""
                    current_streams = current_streams.order_by(f"{order_prefix}tvg_id")
                elif channel_sort_order == "updated_at":
                    order_prefix = "-" if channel_sort_reverse else ""
                    current_streams = current_streams.order_by(
                        f"{order_prefix}updated_at"
                    )
                else:
                    logger.warning(
                        f"Unknown channel_sort_order '{channel_sort_order}' for group '{channel_group.name}'. Using provider order."
                    )
                    order_prefix = "-" if channel_sort_reverse else ""
                    current_streams = current_streams.order_by(f"{order_prefix}id")
            else:
                # Provider order (default) - can still be reversed
                order_prefix = "-" if channel_sort_reverse else ""
                current_streams = current_streams.order_by(f"{order_prefix}id")

            # Get existing auto-created channels for this account (regardless of current group)
            # We'll find them by their stream associations instead of just group location
            existing_channels = Channel.objects.filter(
                auto_created=True, auto_created_by=account
            ).select_related("logo", "epg_data")

            # Create mapping of existing channels by their associated stream
            # This approach finds channels even if they've been moved to different groups
            existing_channel_map = {}
            for channel in existing_channels:
                # Get streams associated with this channel that belong to our M3U account and original group
                channel_streams = ChannelStream.objects.filter(
                    channel=channel,
                    stream__m3u_account=account,
                    stream__channel_group=channel_group,  # Match streams from the original group
                ).select_related("stream")

                # Map each of our M3U account's streams to this channel
                for channel_stream in channel_streams:
                    if channel_stream.stream:
                        existing_channel_map[channel_stream.stream.id] = channel

            # Track which streams we've processed
            processed_stream_ids = set()

            # Check if we have streams - handle both QuerySet and list cases
            has_streams = (
                len(current_streams) > 0
                if streams_is_list
                else current_streams.exists()
            )

            if not has_streams:
                logger.debug(f"No streams found in group {channel_group.name}")
                # Delete all existing auto channels if no streams
                channels_to_delete = [ch for ch in existing_channel_map.values()]
                if channels_to_delete:
                    deleted_count = len(channels_to_delete)
                    Channel.objects.filter(
                        id__in=[ch.id for ch in channels_to_delete]
                    ).delete()
                    channels_deleted += deleted_count
                    logger.debug(
                        f"Deleted {deleted_count} auto channels (no streams remaining)"
                    )
                continue

            # Prepare profiles to assign to new channels
            from apps.channels.models import ChannelProfile, ChannelProfileMembership

            if (
                channel_profile_ids
                and isinstance(channel_profile_ids, list)
                and len(channel_profile_ids) > 0
            ):
                # Convert all to int (in case they're strings)
                try:
                    profile_ids = [int(pid) for pid in channel_profile_ids]
                except Exception:
                    profile_ids = []
                profiles_to_assign = list(
                    ChannelProfile.objects.filter(id__in=profile_ids)
                )
            else:
                profiles_to_assign = list(ChannelProfile.objects.all())

            # Process each current stream
            current_channel_number = start_number

            # Always renumber all existing channels to match current sort order
            # This ensures channels are always in the correct sequence
            channels_to_renumber = []
            temp_channel_number = start_number

            # Get all channel numbers that are already in use by other channels (not auto-created by this account)
            used_numbers = set(
                Channel.objects.exclude(
                    auto_created=True, auto_created_by=account
                ).values_list("channel_number", flat=True)
            )

            for stream in current_streams:
                if stream.id in existing_channel_map:
                    channel = existing_channel_map[stream.id]

                    # Find next available number starting from temp_channel_number
                    target_number = temp_channel_number
                    while target_number in used_numbers:
                        target_number += 1

                    # Add this number to used_numbers so we don't reuse it in this batch
                    used_numbers.add(target_number)

                    if channel.channel_number != target_number:
                        channel.channel_number = target_number
                        channels_to_renumber.append(channel)
                        logger.debug(
                            f"Will renumber channel '{channel.name}' to {target_number}"
                        )

                    temp_channel_number += 1.0
                    if temp_channel_number % 1 != 0:  # Has decimal
                        temp_channel_number = int(temp_channel_number) + 1.0

            # Bulk update channel numbers if any need renumbering
            if channels_to_renumber:
                Channel.objects.bulk_update(channels_to_renumber, ["channel_number"])
                logger.info(
                    f"Renumbered {len(channels_to_renumber)} channels to maintain sort order"
                )

            # Reset channel number counter for processing new channels
            current_channel_number = start_number

            for stream in current_streams:
                processed_stream_ids.add(stream.id)
                try:
                    # Parse custom properties for additional info
                    stream_custom_props = (
                        json.loads(stream.custom_properties)
                        if stream.custom_properties
                        else {}
                    )
                    tvc_guide_stationid = stream_custom_props.get("tvc-guide-stationid")

                    # --- REGEX FIND/REPLACE LOGIC ---
                    original_name = stream.name
                    new_name = original_name
                    if name_regex_pattern is not None:
                        # If replace is None, treat as empty string (remove match)
                        replace = (
                            name_replace_pattern
                            if name_replace_pattern is not None
                            else ""
                        )
                        try:
                            new_name = re.sub(
                                name_regex_pattern, replace, original_name
                            )
                        except re.error as e:
                            logger.warning(
                                f"Regex error for group '{channel_group.name}': {e}. Using original name."
                            )
                            new_name = original_name

                    # Check if we already have a channel for this stream
                    existing_channel = existing_channel_map.get(stream.id)

                    if existing_channel:
                        # Update existing channel if needed (channel number already handled above)
                        channel_updated = False

                        # Use new_name instead of stream.name
                        if existing_channel.name != new_name:
                            existing_channel.name = new_name
                            channel_updated = True

                        if existing_channel.tvg_id != stream.tvg_id:
                            existing_channel.tvg_id = stream.tvg_id
                            channel_updated = True

                        if existing_channel.tvc_guide_stationid != tvc_guide_stationid:
                            existing_channel.tvc_guide_stationid = tvc_guide_stationid
                            channel_updated = True

                        # Check if channel group needs to be updated (in case override was added/changed)
                        if existing_channel.channel_group != target_group:
                            existing_channel.channel_group = target_group
                            channel_updated = True
                            logger.info(
                                f"Moved auto channel '{existing_channel.name}' from '{existing_channel.channel_group.name if existing_channel.channel_group else 'None'}' to '{target_group.name}'"
                            )

                        # Handle logo updates
                        current_logo = None
                        if stream.logo_url:
                            from apps.channels.models import Logo

                            current_logo, _ = Logo.objects.get_or_create(
                                url=stream.logo_url,
                                defaults={
                                    "name": stream.name or stream.tvg_id or "Unknown"
                                },
                            )

                        if existing_channel.logo != current_logo:
                            existing_channel.logo = current_logo
                            channel_updated = True

                        # Handle EPG data updates
                        current_epg_data = None
                        if stream.tvg_id and not force_dummy_epg:
                            current_epg_data = EPGData.objects.filter(
                                tvg_id=stream.tvg_id
                            ).first()

                        if existing_channel.epg_data != current_epg_data:
                            existing_channel.epg_data = current_epg_data
                            channel_updated = True

                        if channel_updated:
                            existing_channel.save()
                            channels_updated += 1
                            logger.debug(
                                f"Updated auto channel: {existing_channel.channel_number} - {existing_channel.name}"
                            )

                        # Update channel profile memberships for existing channels
                        current_memberships = set(
                            ChannelProfileMembership.objects.filter(
                                channel=existing_channel, enabled=True
                            ).values_list("channel_profile_id", flat=True)
                        )

                        target_profile_ids = set(
                            profile.id for profile in profiles_to_assign
                        )

                        # Only update if memberships have changed
                        if current_memberships != target_profile_ids:
                            # Disable all current memberships
                            ChannelProfileMembership.objects.filter(
                                channel=existing_channel
                            ).update(enabled=False)

                            # Enable/create memberships for target profiles
                            for profile in profiles_to_assign:
                                membership, created = (
                                    ChannelProfileMembership.objects.get_or_create(
                                        channel_profile=profile,
                                        channel=existing_channel,
                                        defaults={"enabled": True},
                                    )
                                )
                                if not created and not membership.enabled:
                                    membership.enabled = True
                                    membership.save()

                            logger.debug(
                                f"Updated profile memberships for auto channel: {existing_channel.name}"
                            )

                    else:
                        # Create new channel
                        # Find next available channel number
                        target_number = current_channel_number
                        while target_number in used_numbers:
                            target_number += 1

                        # Add this number to used_numbers
                        used_numbers.add(target_number)

                        channel = Channel.objects.create(
                            channel_number=target_number,
                            name=new_name,
                            tvg_id=stream.tvg_id,
                            tvc_guide_stationid=tvc_guide_stationid,
                            channel_group=target_group,
                            user_level=0,
                            auto_created=True,
                            auto_created_by=account,
                        )

                        # Associate the stream with the channel
                        ChannelStream.objects.create(
                            channel=channel, stream=stream, order=0
                        )

                        # Assign to correct profiles
                        memberships = [
                            ChannelProfileMembership(
                                channel_profile=profile, channel=channel, enabled=True
                            )
                            for profile in profiles_to_assign
                        ]
                        if memberships:
                            ChannelProfileMembership.objects.bulk_create(memberships)

                        # Try to match EPG data
                        if stream.tvg_id and not force_dummy_epg:
                            epg_data = EPGData.objects.filter(
                                tvg_id=stream.tvg_id
                            ).first()
                            if epg_data:
                                channel.epg_data = epg_data
                                channel.save(update_fields=["epg_data"])
                        elif stream.tvg_id and force_dummy_epg:
                            channel.epg_data = None
                            channel.save(update_fields=["epg_data"])

                        # Handle logo
                        if stream.logo_url:
                            from apps.channels.models import Logo

                            logo, _ = Logo.objects.get_or_create(
                                url=stream.logo_url,
                                defaults={
                                    "name": stream.name or stream.tvg_id or "Unknown"
                                },
                            )
                            channel.logo = logo
                            channel.save(update_fields=["logo"])

                        channels_created += 1
                        logger.debug(
                            f"Created auto channel: {channel.channel_number} - {channel.name}"
                        )

                    # Increment channel number for next iteration
                    current_channel_number += 1.0
                    if current_channel_number % 1 != 0:  # Has decimal
                        current_channel_number = int(current_channel_number) + 1.0

                except Exception as e:
                    logger.error(
                        f"Error processing auto channel for stream {stream.name}: {str(e)}"
                    )
                    continue

            # Delete channels for streams that no longer exist
            channels_to_delete = []
            for stream_id, channel in existing_channel_map.items():
                if stream_id not in processed_stream_ids:
                    channels_to_delete.append(channel)

            if channels_to_delete:
                deleted_count = len(channels_to_delete)
                Channel.objects.filter(
                    id__in=[ch.id for ch in channels_to_delete]
                ).delete()
                channels_deleted += deleted_count
                logger.debug(
                    f"Deleted {deleted_count} auto channels for removed streams"
                )

        logger.info(
            f"Auto channel sync complete for account {account.name}: {channels_created} created, {channels_updated} updated, {channels_deleted} deleted"
        )
        return f"Auto sync: {channels_created} channels created, {channels_updated} updated, {channels_deleted} deleted"

    except Exception as e:
        logger.error(f"Error in auto channel sync for account {account_id}: {str(e)}")
        return f"Auto sync error: {str(e)}"


@shared_task
def refresh_single_m3u_account(account_id):
    """Splits M3U processing into chunks and dispatches them as parallel tasks."""
    if not acquire_task_lock("refresh_single_m3u_account", account_id):
        return f"Task already running for account_id={account_id}."

    # Record start time
    refresh_start_timestamp = timezone.now()  # For the cleanup function
    start_time = time.time()  # For tracking elapsed time as float
    streams_created = 0
    streams_updated = 0
    streams_deleted = 0

    try:
        account = M3UAccount.objects.get(id=account_id, is_active=True)
        if not account.is_active:
            logger.debug(f"Account {account_id} is not active, skipping.")
            release_task_lock("refresh_single_m3u_account", account_id)
            return

        # Set status to fetching
        account.status = M3UAccount.Status.FETCHING
        account.save(update_fields=["status"])
    except M3UAccount.DoesNotExist:
        # The M3U account doesn't exist, so delete the periodic task if it exists
        logger.warning(
            f"M3U account with ID {account_id} not found, but task was triggered. Cleaning up orphaned task."
        )

        # Call the helper function to delete the task
        if delete_m3u_refresh_task_by_id(account_id):
            logger.info(
                f"Successfully cleaned up orphaned task for M3U account {account_id}"
            )
        else:
            logger.debug(f"No orphaned task found for M3U account {account_id}")

        release_task_lock("refresh_single_m3u_account", account_id)
        return f"M3UAccount with ID={account_id} not found or inactive, task cleaned up"

    # Fetch M3U lines and handle potential issues
    extinf_data = []
    groups = None

    cache_path = os.path.join(m3u_dir, f"{account_id}.json")
    if os.path.exists(cache_path):
        try:
            with open(cache_path, "r") as file:
                data = json.load(file)

            extinf_data = data["extinf_data"]
            groups = data["groups"]
        except json.JSONDecodeError as e:
            # Handle corrupted JSON file
            logger.error(
                f"Error parsing cached M3U data for account {account_id}: {str(e)}"
            )

            # Backup the corrupted file for potential analysis
            backup_path = f"{cache_path}.corrupted"
            try:
                os.rename(cache_path, backup_path)
                logger.info(f"Renamed corrupted cache file to {backup_path}")
            except OSError as rename_err:
                logger.warning(
                    f"Failed to rename corrupted cache file: {str(rename_err)}"
                )

            # Reset the data to empty structures
            extinf_data = []
            groups = None
        except Exception as e:
            logger.error(f"Unexpected error reading cached M3U data: {str(e)}")
            extinf_data = []
            groups = None

    if not extinf_data:
        try:
            logger.info(f"Calling refresh_m3u_groups for account {account_id}")
            result = refresh_m3u_groups(account_id, full_refresh=True)
            logger.trace(f"refresh_m3u_groups result: {result}")

            # Check for completely empty result or missing groups
            if not result or result[1] is None:
                logger.error(
                    f"Failed to refresh M3U groups for account {account_id}: {result}"
                )
                release_task_lock("refresh_single_m3u_account", account_id)
                return "Failed to update m3u account - download failed or other error"

            extinf_data, groups = result

            # XC accounts can have empty extinf_data but valid groups
            try:
                account = M3UAccount.objects.get(id=account_id)
                is_xc_account = account.account_type == M3UAccount.Types.XC
            except M3UAccount.DoesNotExist:
                is_xc_account = False

            # For XC accounts, empty extinf_data is normal at this stage
            if not extinf_data and not is_xc_account:
                logger.error(f"No streams found for non-XC account {account_id}")
                account.status = M3UAccount.Status.ERROR
                account.last_message = "No streams found in M3U source"
                account.save(update_fields=["status", "last_message"])
                send_m3u_update(
                    account_id, "parsing", 100, status="error", error="No streams found"
                )
        except Exception as e:
            logger.error(f"Exception in refresh_m3u_groups: {str(e)}", exc_info=True)
            account.status = M3UAccount.Status.ERROR
            account.last_message = f"Error refreshing M3U groups: {str(e)}"
            account.save(update_fields=["status", "last_message"])
            send_m3u_update(
                account_id,
                "parsing",
                100,
                status="error",
                error=f"Error refreshing M3U groups: {str(e)}",
            )
            release_task_lock("refresh_single_m3u_account", account_id)
            return "Failed to update m3u account"

    # Only proceed with parsing if we actually have data and no errors were encountered
    # Get account type to handle XC accounts differently
    try:
        is_xc_account = account.account_type == M3UAccount.Types.XC
    except Exception:
        is_xc_account = False

    # Modified validation logic for different account types
    if (not groups) or (not is_xc_account and not extinf_data):
        logger.error(f"No data to process for account {account_id}")
        account.status = M3UAccount.Status.ERROR
        account.last_message = "No data available for processing"
        account.save(update_fields=["status", "last_message"])
        send_m3u_update(
            account_id,
            "parsing",
            100,
            status="error",
            error="No data available for processing",
        )
        release_task_lock("refresh_single_m3u_account", account_id)
        return "Failed to update m3u account, no data available"

    hash_keys = CoreSettings.get_m3u_hash_key().split(",")

    existing_groups = {
        group.name: group.id
        for group in ChannelGroup.objects.filter(
            m3u_account__m3u_account=account,  # Filter by the M3UAccount
            m3u_account__enabled=True,  # Filter by the enabled flag in the join table
        )
    }

    try:
        # Set status to parsing
        account.status = M3UAccount.Status.PARSING
        account.save(update_fields=["status"])

        if account.account_type == M3UAccount.Types.STADNARD:
            logger.debug(
                f"Processing Standard account ({account_id}) with groups: {existing_groups}"
            )
            # Break into batches and process in parallel
            batches = [
                extinf_data[i : i + BATCH_SIZE]
                for i in range(0, len(extinf_data), BATCH_SIZE)
            ]
            task_group = group(
                process_m3u_batch.s(account_id, batch, existing_groups, hash_keys)
                for batch in batches
            )
        else:
            # For XC accounts, get the groups with their custom properties containing xc_id
            logger.debug(f"Processing XC account with groups: {existing_groups}")

            # Get the ChannelGroupM3UAccount entries with their custom_properties
            channel_group_relationships = ChannelGroupM3UAccount.objects.filter(
                m3u_account=account, enabled=True
            ).select_related("channel_group")

            filtered_groups = {}
            for rel in channel_group_relationships:
                group_name = rel.channel_group.name
                group_id = rel.channel_group.id

                # Load the custom properties with the xc_id
                try:
                    custom_props = (
                        json.loads(rel.custom_properties)
                        if rel.custom_properties
                        else {}
                    )
                    if "xc_id" in custom_props:
                        filtered_groups[group_name] = {
                            "xc_id": custom_props["xc_id"],
                            "channel_group_id": group_id,
                        }
                        logger.debug(
                            f"Added group {group_name} with xc_id {custom_props['xc_id']}"
                        )
                    else:
                        logger.warning(
                            f"No xc_id found in custom properties for group {group_name}"
                        )
                except (json.JSONDecodeError, KeyError) as e:
                    logger.error(
                        f"Error parsing custom properties for group {group_name}: {str(e)}"
                    )

            logger.info(
                f"Filtered {len(filtered_groups)} groups for processing: {filtered_groups}"
            )

            # Batch the groups
            filtered_groups_list = list(filtered_groups.items())
            batches = [
                dict(filtered_groups_list[i : i + 2])
                for i in range(0, len(filtered_groups_list), 2)
            ]

            logger.info(f"Created {len(batches)} batches for XC processing")
            task_group = group(
                process_xc_category.s(account_id, batch, existing_groups, hash_keys)
                for batch in batches
            )

        total_batches = len(batches)
        completed_batches = 0
        streams_processed = 0  # Track total streams processed
        logger.debug(
            f"Dispatched {len(batches)} parallel tasks for account_id={account_id}."
        )

        # result = task_group.apply_async()
        result = task_group.apply_async()

        # Wait for all tasks to complete and collect their result IDs
        completed_task_ids = set()
        while completed_batches < total_batches:
            for async_result in result:
                if (
                    async_result.ready() and async_result.id not in completed_task_ids
                ):  # If the task has completed and we haven't counted it
                    task_result = async_result.result  # The result of the task
                    logger.debug(f"Task completed with result: {task_result}")

                    # Extract stream counts from result string if available
                    if isinstance(task_result, str):
                        try:
                            created_match = re.search(r"(\d+) created", task_result)
                            updated_match = re.search(r"(\d+) updated", task_result)

                            if created_match and updated_match:
                                created_count = int(created_match.group(1))
                                updated_count = int(updated_match.group(1))
                                streams_processed += created_count + updated_count
                                streams_created += created_count
                                streams_updated += updated_count
                        except (AttributeError, ValueError):
                            pass

                    completed_batches += 1
                    completed_task_ids.add(
                        async_result.id
                    )  # Mark this task as processed

                    # Calculate progress
                    progress = int((completed_batches / total_batches) * 100)

                    # Calculate elapsed time and estimated remaining time
                    current_elapsed = time.time() - start_time
                    if progress > 0:
                        estimated_total = (current_elapsed / progress) * 100
                        time_remaining = max(0, estimated_total - current_elapsed)
                    else:
                        time_remaining = 0

                    # Send progress update via Channels
                    # Don't send 100% because we want to clean up after
                    if progress == 100:
                        progress = 99

                    send_m3u_update(
                        account_id,
                        "parsing",
                        progress,
                        elapsed_time=current_elapsed,
                        time_remaining=time_remaining,
                        streams_processed=streams_processed,
                    )

                    # Optionally remove completed task from the group to prevent processing it again
                    result.remove(async_result)
                else:
                    logger.trace(f"Task is still running.")

        # Ensure all database transactions are committed before cleanup
        logger.info(
            f"All {total_batches} tasks completed, ensuring DB transactions are committed before cleanup"
        )
        # Force a simple DB query to ensure connection sync
        Stream.objects.filter(
            id=-1
        ).exists()  # This will never find anything but ensures DB sync

        # Now run cleanup
        streams_deleted = cleanup_streams(account_id, refresh_start_timestamp)

        # Run auto channel sync after successful refresh
        auto_sync_message = ""
        try:
            sync_result = sync_auto_channels(
                account_id, scan_start_time=str(refresh_start_timestamp)
            )
            logger.info(
                f"Auto channel sync result for account {account_id}: {sync_result}"
            )
            if sync_result and "created" in sync_result:
                auto_sync_message = f" {sync_result}."
        except Exception as e:
            logger.error(
                f"Error running auto channel sync for account {account_id}: {str(e)}"
            )

        # Calculate elapsed time
        elapsed_time = time.time() - start_time

        # Set status to success and update timestamp BEFORE sending the final update
        account.status = M3UAccount.Status.SUCCESS
        account.last_message = (
            f"Processing completed in {elapsed_time:.1f} seconds. "
            f"Streams: {streams_created} created, {streams_updated} updated, {streams_deleted} removed. "
            f"Total processed: {streams_processed}.{auto_sync_message}"
        )
        account.updated_at = timezone.now()
        account.save(update_fields=["status", "last_message", "updated_at"])

        # Send final update with complete metrics and explicitly include success status
        send_m3u_update(
            account_id,
            "parsing",
            100,
            status="success",  # Explicitly set status to success
            elapsed_time=elapsed_time,
            time_remaining=0,
            streams_processed=streams_processed,
            streams_created=streams_created,
            streams_updated=streams_updated,
            streams_deleted=streams_deleted,
            message=account.last_message,
        )

    except Exception as e:
        logger.error(f"Error processing M3U for account {account_id}: {str(e)}")
        account.status = M3UAccount.Status.ERROR
        account.last_message = f"Error processing M3U: {str(e)}"
        account.save(update_fields=["status", "last_message"])
        raise  # Re-raise the exception for Celery to handle

    release_task_lock("refresh_single_m3u_account", account_id)

    # Aggressive garbage collection
    del existing_groups, extinf_data, groups, batches
    from core.utils import cleanup_memory

    cleanup_memory(log_usage=True, force_collection=True)

    # Clean up cache file since we've fully processed it
    if os.path.exists(cache_path):
        os.remove(cache_path)

    return f"Dispatched jobs complete."


def send_m3u_update(account_id, action, progress, **kwargs):
    # Start with the base data dictionary
    data = {
        "progress": progress,
        "type": "m3u_refresh",
        "account": account_id,
        "action": action,
    }

    # Add the status and message if not already in kwargs
    try:
        account = M3UAccount.objects.get(id=account_id)
        if account:
            if "status" not in kwargs:
                data["status"] = account.status
            if "message" not in kwargs and account.last_message:
                data["message"] = account.last_message
    except:
        pass  # If account can't be retrieved, continue without these fields

    # Add the additional key-value pairs from kwargs
    data.update(kwargs)
    send_websocket_update("updates", "update", data, collect_garbage=False)

    # Explicitly clear data reference to help garbage collection
    data = None