from django.shortcuts import get_object_or_404
from boards.models import Tag

__author__ = 'neko259'

SESSION_SETTING = 'setting'

# Remove this, it is not used any more cause there is a user's permission
PERMISSION_MODERATE = 'moderator'

SETTING_THEME = 'theme'
SETTING_FAVORITE_TAGS = 'favorite_tags'
SETTING_HIDDEN_TAGS = 'hidden_tags'
SETTING_PERMISSIONS = 'permissions'
SETTING_USERNAME = 'username'
SETTING_LAST_NOTIFICATION_ID = 'last_notification'

DEFAULT_THEME = 'md'


class SettingsManager:
    """
    Base settings manager class. get_setting and set_setting methods should
    be overriden.
    """
    def __init__(self):
        pass

    def get_theme(self):
        theme = self.get_setting(SETTING_THEME)
        if not theme:
            theme = DEFAULT_THEME
            self.set_setting(SETTING_THEME, theme)

        return theme

    def set_theme(self, theme):
        self.set_setting(SETTING_THEME, theme)

    def has_permission(self, permission):
        permissions = self.get_setting(SETTING_PERMISSIONS)
        if permissions:
            return permission in permissions
        else:
            return False

    def get_setting(self, setting):
        pass

    def set_setting(self, setting, value):
        pass

    def add_permission(self, permission):
        permissions = self.get_setting(SETTING_PERMISSIONS)
        if not permissions:
            permissions = [permission]
        else:
            permissions.append(permission)
        self.set_setting(SETTING_PERMISSIONS, permissions)

    def del_permission(self, permission):
        permissions = self.get_setting(SETTING_PERMISSIONS)
        if not permissions:
            permissions = []
        else:
            permissions.remove(permission)
        self.set_setting(SETTING_PERMISSIONS, permissions)

    def get_fav_tags(self):
        tag_names = self.get_setting(SETTING_FAVORITE_TAGS)
        tags = []
        if tag_names:
            tags = Tag.objects.filter(name__in=tag_names)
        return tags

    def add_fav_tag(self, tag):
        tags = self.get_setting(SETTING_FAVORITE_TAGS)
        if not tags:
            tags = [tag.name]
        else:
            if not tag.name in tags:
                tags.append(tag.name)

        tags.sort()
        self.set_setting(SETTING_FAVORITE_TAGS, tags)

    def del_fav_tag(self, tag):
        tags = self.get_setting(SETTING_FAVORITE_TAGS)
        if tag.name in tags:
            tags.remove(tag.name)
            self.set_setting(SETTING_FAVORITE_TAGS, tags)

    def get_hidden_tags(self):
        tag_names = self.get_setting(SETTING_HIDDEN_TAGS)
        tags = []
        if tag_names:
            for tag_name in tag_names:
                tag = get_object_or_404(Tag, name=tag_name)
                tags.append(tag)

        return tags

    def add_hidden_tag(self, tag):
        tags = self.get_setting(SETTING_HIDDEN_TAGS)
        if not tags:
            tags = [tag.name]
        else:
            if not tag.name in tags:
                tags.append(tag.name)

        tags.sort()
        self.set_setting(SETTING_HIDDEN_TAGS, tags)

    def del_hidden_tag(self, tag):
        tags = self.get_setting(SETTING_HIDDEN_TAGS)
        if tag.name in tags:
            tags.remove(tag.name)
            self.set_setting(SETTING_HIDDEN_TAGS, tags)


class SessionSettingsManager(SettingsManager):
    """
    Session-based settings manager. All settings are saved to the user's
    session.
    """
    def __init__(self, session):
        SettingsManager.__init__(self)
        self.session = session

    def get_setting(self, setting):
        if setting in self.session:
            return self.session[setting]
        else:
            return None

    def set_setting(self, setting, value):
        self.session[setting] = value


def get_settings_manager(request) -> SettingsManager:
    """
    Get settings manager based on the request object. Currently only
    session-based manager is supported. In the future, cookie-based or
    database-based managers could be implemented.
    """
    return SessionSettingsManager(request.session)