import logging
from typing import cast

from fansifter_common.adapters.sendgrid.models import FanData

from app.adapters.redis import redis_client
from app.config import settings
from app.utils import hash_email

logger = logging.getLogger(__name__)


def make_key(automated_email_id: str, email_hash: bytes) -> str:
    return f"dedup:automated_email:{automated_email_id}:{email_hash.hex()}"


def filter_unsent(
    automated_email_id: str, fan_data_list: list[FanData]
) -> list[FanData]:
    if not fan_data_list:
        return []

    hashes = [hash_email(fan_data.email) for fan_data in fan_data_list]
    keys = [make_key(automated_email_id, h) for h in hashes]
    results = cast(list[bytes | None], redis_client.mget(keys))

    unsent: list[FanData] = [
        fan_data
        for fan_data, value in zip(fan_data_list, results, strict=True)
        if value is None
    ]

    if skipped := len(fan_data_list) - len(unsent):
        logger.info(
            "Skipping %d already sent fans.",
            skipped,
            extra={"automated_email_id": automated_email_id},
        )

    return unsent


def mark_sent(automated_email_id: str, fan_data_list: list[FanData]) -> None:
    if not fan_data_list:
        return

    hashes = [hash_email(fan_data.email) for fan_data in fan_data_list]
    with redis_client.pipeline() as pipe:
        for h in hashes:
            pipe.set(make_key(automated_email_id, h), 1, ex=settings.redis_dedup_ttl)
        pipe.execute()