from typing import Union

from django.contrib.auth.models import User
from django.utils import timezone

from bookmarks.models import Bookmark, parse_tag_string
from bookmarks.services.tags import get_or_create_tags
from bookmarks.services import website_loader
from bookmarks.services import tasks


def create_bookmark(bookmark: Bookmark, tag_string: str, current_user: User):
    # If URL is already bookmarked, then update it
    existing_bookmark: Bookmark = Bookmark.objects.filter(owner=current_user, url=bookmark.url).first()

    if existing_bookmark is not None:
        _merge_bookmark_data(bookmark, existing_bookmark)
        return update_bookmark(existing_bookmark, tag_string, current_user)

    # Update website info
    _update_website_metadata(bookmark)
    # Set currently logged in user as owner
    bookmark.owner = current_user
    # Set dates
    bookmark.date_added = timezone.now()
    bookmark.date_modified = timezone.now()
    bookmark.save()
    # Update tag list
    _update_bookmark_tags(bookmark, tag_string, current_user)
    bookmark.save()
    # Create snapshot on web archive
    tasks.create_web_archive_snapshot(current_user, bookmark, False)
    # Load favicon
    tasks.load_favicon(current_user, bookmark)

    return bookmark


def update_bookmark(bookmark: Bookmark, tag_string, current_user: User):
    # Detect URL change
    original_bookmark = Bookmark.objects.get(id=bookmark.id)
    has_url_changed = original_bookmark.url != bookmark.url
    # Update tag list
    _update_bookmark_tags(bookmark, tag_string, current_user)
    # Update dates
    bookmark.date_modified = timezone.now()
    bookmark.save()
    # Update favicon
    tasks.load_favicon(current_user, bookmark)

    if has_url_changed:
        # Update web archive snapshot, if URL changed
        tasks.create_web_archive_snapshot(current_user, bookmark, True)
        # Only update website metadata if URL changed
        _update_website_metadata(bookmark)
        bookmark.save()

    return bookmark


def archive_bookmark(bookmark: Bookmark):
    bookmark.is_archived = True
    bookmark.date_modified = timezone.now()
    bookmark.save()
    return bookmark


def archive_bookmarks(bookmark_ids: [Union[int, str]], current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)

    Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).update(is_archived=True,
                                                                                      date_modified=timezone.now())


def unarchive_bookmark(bookmark: Bookmark):
    bookmark.is_archived = False
    bookmark.date_modified = timezone.now()
    bookmark.save()
    return bookmark


def unarchive_bookmarks(bookmark_ids: [Union[int, str]], current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)

    Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).update(is_archived=False,
                                                                                      date_modified=timezone.now())


def delete_bookmarks(bookmark_ids: [Union[int, str]], current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)

    Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).delete()


def tag_bookmarks(bookmark_ids: [Union[int, str]], tag_string: str, current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)
    owned_bookmark_ids = Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).values_list('id',
                                                                                                                flat=True)
    tag_names = parse_tag_string(tag_string)
    tags = get_or_create_tags(tag_names, current_user)

    BookmarkToTagRelationShip = Bookmark.tags.through
    relationships = []
    for tag in tags:
        for bookmark_id in owned_bookmark_ids:
            relationships.append(BookmarkToTagRelationShip(bookmark_id=bookmark_id, tag=tag))

    # Insert all bookmark -> tag associations at once, should ignore errors if association already exists
    BookmarkToTagRelationShip.objects.bulk_create(relationships, ignore_conflicts=True)
    Bookmark.objects.filter(id__in=owned_bookmark_ids).update(date_modified=timezone.now())


def untag_bookmarks(bookmark_ids: [Union[int, str]], tag_string: str, current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)
    owned_bookmark_ids = Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).values_list('id',
                                                                                                                flat=True)
    tag_names = parse_tag_string(tag_string)
    tags = get_or_create_tags(tag_names, current_user)

    BookmarkToTagRelationShip = Bookmark.tags.through
    for tag in tags:
        # Remove all bookmark -> tag associations for the owned bookmarks and the current tag
        BookmarkToTagRelationShip.objects.filter(bookmark_id__in=owned_bookmark_ids, tag=tag).delete()

    Bookmark.objects.filter(id__in=owned_bookmark_ids).update(date_modified=timezone.now())


def mark_bookmarks_as_read(bookmark_ids: [Union[int, str]], current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)

    Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).update(unread=False,
                                                                                      date_modified=timezone.now())


def mark_bookmarks_as_unread(bookmark_ids: [Union[int, str]], current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)

    Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).update(unread=True,
                                                                                      date_modified=timezone.now())


def share_bookmarks(bookmark_ids: [Union[int, str]], current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)

    Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).update(shared=True,
                                                                                      date_modified=timezone.now())


def unshare_bookmarks(bookmark_ids: [Union[int, str]], current_user: User):
    sanitized_bookmark_ids = _sanitize_id_list(bookmark_ids)

    Bookmark.objects.filter(owner=current_user, id__in=sanitized_bookmark_ids).update(shared=False,
                                                                                      date_modified=timezone.now())


def _merge_bookmark_data(from_bookmark: Bookmark, to_bookmark: Bookmark):
    to_bookmark.title = from_bookmark.title
    to_bookmark.description = from_bookmark.description
    to_bookmark.notes = from_bookmark.notes
    to_bookmark.unread = from_bookmark.unread
    to_bookmark.shared = from_bookmark.shared


def _update_website_metadata(bookmark: Bookmark):
    metadata = website_loader.load_website_metadata(bookmark.url)
    bookmark.website_title = metadata.title
    bookmark.website_description = metadata.description


def _update_bookmark_tags(bookmark: Bookmark, tag_string: str, user: User):
    tag_names = parse_tag_string(tag_string)
    tags = get_or_create_tags(tag_names, user)
    bookmark.tags.set(tags)


def _sanitize_id_list(bookmark_ids: [Union[int, str]]) -> [int]:
    # Convert string ids to int if necessary
    return [int(bm_id) if isinstance(bm_id, str) else bm_id for bm_id in bookmark_ids]