"""
Configuración de plantilla CSV para Tipos de Cambio (EstructuraCatTiposCambio.xls).
Solo se leen columnas definidas aquí; el resto se ignora.
"""

from typing import Dict, List, Any, Optional

from ..common.cell_value import cell_to_str
from ..common.csv_hint_inject import inject_max_char_hints_into_columns
from ..common.inject_csv_labels_en import inject_en_labels_into_template_columns
from ..common.template_locale import merge_download_header_into_lookup, merge_labels_into_lookup
from .csv_max_chars_for_headers import EXCHANGE_RATE_CSV_MAX_CHARS

TEMPLATE_COLUMNS: Dict[str, List[Dict[str, Any]]] = {
    "exchange_rates": [
        {"canonical": "FECHA", "aliases": ["FECHA APLICABLE", "DATE", "FECHA TIPO CAMBIO"]},
        {"canonical": "VALOR", "aliases": ["TIPO_DE_CAMBIO", "TIPO CAMBIO", "TIPO DE CAMBIO", "VALUE", "RATE"]},
        {"canonical": "MONEDA_LOCAL", "aliases": ["MONEDA LOCAL", "LOCAL_CURRENCY", "MONEDA BASE"]},
        {"canonical": "MONEDA_EXTRANJERA", "aliases": ["MONEDA EXTRANJERA", "FOREIGN_CURRENCY", "MONEDA DESTINO"]},
    ],
}

inject_en_labels_into_template_columns(TEMPLATE_COLUMNS)

inject_max_char_hints_into_columns(
    TEMPLATE_COLUMNS.get("exchange_rates"), EXCHANGE_RATE_CSV_MAX_CHARS
)


def build_normalized_lookup(normalize_header_fn, template_id: str = "exchange_rates") -> Dict[str, str]:
    """normalized_header -> canonical_name para plantilla exchange_rates."""
    cols = TEMPLATE_COLUMNS.get(template_id)
    if not cols:
        return {}
    lookup: Dict[str, str] = {}
    for item in cols:
        canonical = item["canonical"]
        lookup[normalize_header_fn(canonical)] = canonical
        for alias in item.get("aliases") or []:
            lookup[normalize_header_fn(alias)] = canonical
        merge_labels_into_lookup(item, canonical, normalize_header_fn, lookup)
        merge_download_header_into_lookup(item, canonical, normalize_header_fn, lookup)
    return lookup


def row_from_template(row: Dict[str, Any], normalize_header_fn, template_id: str = "exchange_rates") -> Dict[str, Any]:
    """Fila CSV con solo columnas de la plantilla, en nombres canónicos."""
    lookup = build_normalized_lookup(normalize_header_fn, template_id)
    if not lookup:
        return {normalize_header_fn(k): cell_to_str(v) for k, v in row.items()}
    out: Dict[str, Any] = {}
    for csv_header, value in row.items():
        key_norm = normalize_header_fn(csv_header)
        if key_norm in lookup:
            out[lookup[key_norm]] = cell_to_str(value)
    return out
