from collections.abc import Sequence
from dataclasses import dataclass
from typing import ClassVar

from anydi import singleton
from fansifter_common.auth.requests import AuthAccountFilterRequest
from fansifter_common.auth.services import AuthService
from fansifter_common.auth.types import Permission

from ows_text_campaigns.campaigns.enums import CampaignStatus
from ows_text_campaigns.campaigns.models import Campaign
from ows_text_campaigns.campaigns.repositories import CampaignRepository
from ows_text_campaigns.campaigns.services import CampaignService
from ows_text_campaigns.campaigns.types import CampaignCriteria, CampaignOrderBy


@dataclass(kw_only=True)
class GetCampaignsRequest(AuthAccountFilterRequest):
    DEFAULT_LIMIT: ClassVar[int] = 50
    DEFAULT_OFFSET: ClassVar[int] = 0
    DEFAULT_ORDER_BY: ClassVar[list[CampaignOrderBy]] = ["updatedAt.desc"]

    search: str | None
    global_participant_ids: set[str] | None
    statuses: list[CampaignStatus] | None
    order_by: list[CampaignOrderBy]
    limit: int
    offset: int


@dataclass
class GetCampaignsResponse:
    items: Sequence[Campaign]
    total: int


@singleton
class GetCampaignsHandler:
    permission = Permission("text_campaign", "view")

    def __init__(
        self,
        auth_service: AuthService,
        campaign_repository: CampaignRepository,
        campaign_service: CampaignService,
    ) -> None:
        self.auth_service = auth_service
        self.campaign_repository = campaign_repository
        self.campaign_service = campaign_service

    def handle(self, request: GetCampaignsRequest) -> GetCampaignsResponse:
        account_access = self.auth_service.authorize_for_permission(
            request.identity_id, permission=self.permission
        )

        vendor_ids = account_access.filter_vendor_ids(request.vendor_id)
        subaccount_ids = account_access.filter_subaccount_ids(request.subaccount_id)

        criteria = CampaignCriteria(
            vendor_ids=set(vendor_ids),
            subaccount_ids=set(subaccount_ids),
            global_participant_ids=request.global_participant_ids,
            search=request.search,
            statuses=request.statuses,
        )

        total = self.campaign_repository.count_by_criteria(criteria)
        if total == 0:
            return GetCampaignsResponse(total=0, items=[])

        items = self.campaign_repository.find_by_criteria(
            criteria,
            order_by=request.order_by,
            limit=request.limit,
            offset=request.offset,
        )

        # Prefetch audience
        self.campaign_service.prefetch_audience(items)

        self.campaign_service.prefetch_analytics(items)

        return GetCampaignsResponse(total=total, items=items)