from collections import defaultdict
from datetime import date, timedelta
from typing import Dict, List, Tuple

from server.client import services
from server.constants.common import LAST_WEEK_START_DAYS, PREVIOUS_WEEK_START_DAYS
from server.utils.tracks import get_weekly_summary


async def get_tracks_weekly_streams(
    dsp_list: List[str], isrc_list: List[str], end_date: date, country_code: str
) -> Tuple[Dict[str, int], Dict[str, int]]:
    """Get tracks two week streams sum.

    Args:
        dsp_list: DSP code list.
        isrc_list: Tracks ISRC list.
        end_date: Latest date.
        country_code: Streams country code.

    Returns:
        Current and previous week streams maps by ISRC.
    """

    start_date = end_date - timedelta(days=PREVIOUS_WEEK_START_DAYS)
    week_start_date = end_date - timedelta(days=LAST_WEEK_START_DAYS)

    streams_list = await services.dsp.get_streams_isrc_chunks(
        isrc=isrc_list,
        start_date=start_date,
        end_date=end_date,
        dsp=dsp_list,
        country_code=country_code,
        group_by="date",
    )

    last_streams_map, previous_streams_map = defaultdict(int), defaultdict(int)

    for item in streams_list:
        item_date, isrc = item.get("date"), item.get("isrc")
        if not item_date or not isrc:
            continue

        current_map = last_streams_map if date.fromisoformat(item_date) >= week_start_date else previous_streams_map
        current_map[isrc] += item.get("streams", 0)

    return last_streams_map, previous_streams_map


async def get_tracks_weekly_streams_summary(
    dsp_list: List[str], isrc_list: List[str], end_date: date, country_code: str
) -> Dict[str, dict]:
    last_streams_map, previous_streams_map = await get_tracks_weekly_streams(
        dsp_list, isrc_list, end_date, country_code
    )

    return get_weekly_summary(last_streams_map, previous_streams_map, prefix="streams")