from __future__ import annotations

import datetime
from collections import defaultdict
from dataclasses import dataclass

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

from ows_text_campaigns.campaigns.repositories import CampaignRepository
from ows_text_campaigns.campaigns.services import CampaignService
from ows_text_campaigns.campaigns.types import CampaignSendCountry, SendTimezone


@dataclass(kw_only=True)
class GetCampaignSendTimezonesRequest(AuthRequest):
    campaign_id: str
    send_at: datetime.datetime


@dataclass(kw_only=True)
class GetCampaignSendTimezonesResponse:
    send_at: datetime.datetime
    countries: list[CampaignSendCountry]


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

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

    def handle(
        self, request: GetCampaignSendTimezonesRequest
    ) -> GetCampaignSendTimezonesResponse:
        campaign = self.campaign_service.get_campaign(request.campaign_id)

        self.auth_service.authorize_account(
            request.identity_id,
            account=campaign.account,
            permission=self.permission,
        )

        # Get available timezones
        timezones = self.campaign_repository.get_send_timezone(
            campaign_id=campaign.id,
            send_at=request.send_at,
        )

        timezone_adjustments: set[str] = set()
        for adjustment in campaign.timezone_adjustments or []:
            timezone_adjustments.add(adjustment.key)

        timezone_by_country: dict[str, list[SendTimezone]] = defaultdict(list)
        for timezone in timezones:
            if timezone.adjustment_key in timezone_adjustments:
                timezone.is_adjusted = True
            timezone_by_country[timezone.country_code].append(timezone)

        # Build countries
        countries = [
            CampaignSendCountry(country_code=country_code, timezones=timezones)
            for country_code, timezones in timezone_by_country.items()
        ]

        return GetCampaignSendTimezonesResponse(
            send_at=request.send_at,
            countries=countries,
        )