"""Fetch exchange rates from the configured provider (Frankfurter by default).

Fetched rates arrive UNCONFIRMED: Control C5 still blocks the close until a person
confirms them for the reporting month — this endpoint only replaces typing rates by hand."""
from __future__ import annotations

import datetime as dt

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel
from sqlalchemy.orm import Session as OrmSession

from ...services.fx_service import FxProviderError, seed_daily_fx, seed_session_fx
from ..deps import db_dep, ensure_editable, get_session_or_404

router = APIRouter(prefix="/api/sessions", tags=["fx"])


@router.post("/{session_id}/fx/fetch")
def fetch_month_end_rates(session_id: int, db: OrmSession = Depends(db_dep)) -> dict:
    """Pre-fill this closing's FX table with the provider's month-end rates."""
    s = get_session_or_404(session_id, db)
    ensure_editable(s)
    try:
        return seed_session_fx(db, s)
    except FxProviderError as e:
        raise HTTPException(502, f"{e} — enter the rates manually on the Controls tab.")


class DailyFetchIn(BaseModel):
    marketplace: str | None = None      # default: every non-USD marketplace in the closing
    date_from: dt.date | None = None    # default: the closing's earliest dated transaction
    date_to: dt.date | None = None      # default: month-end (or the latest transaction)


@router.post("/{session_id}/fx/fetch-daily")
def fetch_daily_rates(session_id: int, body: DailyFetchIn | None = None,
                      db: OrmSession = Depends(db_dep)) -> dict:
    """(Re-)fetch the per-date FX table from the provider. Processing already does this
    automatically; the explicit fetch also replaces hand-entered overrides."""
    s = get_session_or_404(session_id, db)
    ensure_editable(s)
    body = body or DailyFetchIn()
    try:
        return seed_daily_fx(db, s, marketplace=body.marketplace,
                             date_from=body.date_from, date_to=body.date_to)
    except FxProviderError as e:
        raise HTTPException(502, f"{e} — enter daily rates manually on the AR Ledger tab.")