from .models import *
from .serializers import *

from users.models import *
from common.models.choiceModels import InvitationStatus


ACTION_FIELD_MAP = {
            'like': 'likers',
            'scrap': 'scrappers',
        }

class ProjectBeforeRelCheckService:
    @staticmethod
    def check_user_project_rel(action_type: str, project: Project, user):
        action = ACTION_FIELD_MAP.get(action_type)
        if not action:
            raise ValueError(f"'{action_type}' is unsupported action type")

        if getattr(project, action).filter(id=user.id).exists():
            return True
        else:
            return False

class ProjectStateChangeService:
    @staticmethod
    def change_user_project_rel(action_type: str, project: Project, user, add=True):
        action = ACTION_FIELD_MAP.get(action_type)
        if not action:
            raise ValueError(f"'{action_type}' is unsupported action type")

        user_method = getattr(getattr(project, action), 'add' if add else 'remove')
        user_method(user)

    @staticmethod
    def change_count_project_state(action_type: str, project: Project, add=True):
        action = ACTION_FIELD_MAP.get(action_type)
        if not action:
            raise ValueError(f"'{action_type}' is unsupported action type")
        field_name = action_type + '_count'
        current_count = getattr(project, field_name)
        now_count = current_count+1 if add else max(current_count-1, 0)
        setattr(project, field_name, now_count)
        project.save(update_fields=[field_name])


class ProjectInvitationService:
    @staticmethod
    def create_project_invitation(project: Project, from_user: User, to_user: User, notification: Notification):
        return ProjectInvitation.objects.create(
            project=project, 
            from_user=from_user, 
            to_user=to_user, 
            status= InvitationStatus.PENDING,
            notification=notification
            )