from functools import partial
from typing import ClassVar
import datetime
from dataclasses import dataclass
import pandas as pd
import dateutil.parser as dparser

from serenitas.utils.remote import SftpClient
from serenitas.ops.trade_dataclasses import Fund
from serenitas.utils.db import dawn_engine, dbconn
from serenitas.analytics.dates import next_business_day
from serenitas.analytics.exceptions import MissingDataError

from .misc import dt_from_citco


@dataclass
class CitcoReport:
    report_name: ClassVar
    table: ClassVar
    knowledge_date: datetime.date = None
    _conn: dbconn = dbconn("dawndb")
    _sftp: ClassVar = SftpClient.from_creds("citco", folder="outgoing")
    date_cols: ClassVar = []
    dtkey: ClassVar
    _registry = {}

    def __init_subclass__(cls, table, date_cols, dtkey):
        cls.table = table
        cls.date_cols = date_cols
        cls.dtkey = dtkey
        cls._registry[table] = cls

    def __class_getitem__(cls, table):
        return cls._registry[table]

    def __post_init__(self):
        if not self.report_file_name:
            raise MissingDataError(
                f"No reports for {self.fund}:{self.table} on {self.date}"
            )
        self.knowledge_date = datetime.datetime.combine(
            next_business_day(self.date), self.dtkey_fun(self.report_file_name).time()
        )

    @staticmethod
    def get_report_date(cob):
        return cob

    @classmethod
    def get_report(cls, date, fund):
        prefix = cls.get_prefix(fund)
        dtkey_fun = cls.get_dt_fun(fund)
        report_date = cls.get_report_date(date)
        return max(
            [
                f
                for f in cls._sftp.client.listdir()
                if (prefix in f) and (dtkey_fun(f).date() == report_date)
            ],
            key=dtkey_fun,
        )

    @classmethod
    def get_df(cls, report_name):
        with cls._sftp.client.open(report_name) as fh:
            df = pd.read_csv(fh, parse_dates=cls.date_cols, infer_datetime_format=True)
            df["row"] = df.index
            df.columns = df.columns.str.lower()
            df.columns = df.columns.str.replace(" ", "_")
            df["period_end_date"] = cls.date
            df["knowledge_date"] = cls.knowledge_date
            df["fund"] = cls.fund
            return df

    @classmethod
    def to_db(cls, date, fund):
        report_name = cls.get_report(date, fund)
        df = cls.get_df(report_name)
        with cls._conn.cursor() as c:
            c.execute(
                f"DELETE FROM {cls.table} WHERE period_end_date=%s AND fund=%s",
                (
                    date,
                    fund,
                ),
            )
        cls._conn.commit()
        if "strategy" in df.columns:
            df["strategy"] = df["strategy"].str.replace("/M_|/SER_", "/", regex=True)
        df.to_sql(self.table, dawn_engine, if_exists="append", index=False)

    @classmethod
    def get_dt_fun(cls, fund):
        def dt_fun(fname, date):
            ts = fname.removeprefix(cls.get_prefix(fund)).removesuffix(".csv")
            return dparser(ts)

        return dt_fun


class AccruedReport(
    CitcoReport,
    table="isosel_accrued",
    date_cols=[
        "Init Date",
        "Init Settle Date",
        "Liqd Date",
        "Liqd Settle Date",
        "Bond Maturity",
        "Orig Date",
        "Start Date",
        "End Date",
    ],
    dtkey="%Y%m%d%H%M%S",
):
    @staticmethod
    def get_report_date(cob):
        return next_business_day(cob)

    @staticmethod
    def get_prefix(fund):
        return f"100502500_INNOCAP_{fund}_"


class AllReport(
    CitcoReport,
    table="citco_reports",
    date_cols=["Maturity Date"],
    dtkey="%Y%m%d.%H%M%S",
):
    @staticmethod
    def get_prefix(fund):
        return f"SPOS4X_INNOCAP_{fund}_D_{'IM' if fund =='ISOSEL' else 'IMCG'}."