"""
Field Normalization Module

Normalizes field values to generate multiple candidate forms for matching.

This module now delegates to individual normalizer modules for each field type.
Each normalizer is a separate, reusable module that can be used independently.
"""

from dataclasses import dataclass
from typing import Callable
from src.utils.text_cleaner import TextCleaner

# Import individual normalizers
from .normalizers import (
    InvoiceNumberNormalizer,
    OCRNormalizer,
    BankgiroNormalizer,
    PlusgiroNormalizer,
    AmountNormalizer,
    DateNormalizer,
    OrganisationNumberNormalizer,
    SupplierAccountsNormalizer,
    CustomerNumberNormalizer,
)


@dataclass
class NormalizedValue:
    """Represents a normalized value with its variants."""
    original: str
    variants: list[str]
    field_type: str


class FieldNormalizer:
    """
    Handles normalization of different invoice field types.

    This class now acts as a facade that delegates to individual
    normalizer modules. Each field type has its own specialized
    normalizer for better modularity and reusability.
    """

    # Instantiate individual normalizers
    _invoice_number = InvoiceNumberNormalizer()
    _ocr_number = OCRNormalizer()
    _bankgiro = BankgiroNormalizer()
    _plusgiro = PlusgiroNormalizer()
    _amount = AmountNormalizer()
    _date = DateNormalizer()
    _organisation_number = OrganisationNumberNormalizer()
    _supplier_accounts = SupplierAccountsNormalizer()
    _customer_number = CustomerNumberNormalizer()

    # Common Swedish month names for backward compatibility
    SWEDISH_MONTHS = DateNormalizer.SWEDISH_MONTHS

    @staticmethod
    def clean_text(text: str) -> str:
        """
        Remove invisible characters and normalize whitespace and dashes.

        Delegates to shared TextCleaner for consistency.
        """
        return TextCleaner.clean_text(text)

    @staticmethod
    def normalize_invoice_number(value: str) -> list[str]:
        """
        Normalize invoice number.

        Delegates to InvoiceNumberNormalizer.
        """
        return FieldNormalizer._invoice_number.normalize(value)

    @staticmethod
    def normalize_ocr_number(value: str) -> list[str]:
        """
        Normalize OCR number (Swedish payment reference).

        Delegates to OCRNormalizer.
        """
        return FieldNormalizer._ocr_number.normalize(value)

    @staticmethod
    def normalize_bankgiro(value: str) -> list[str]:
        """
        Normalize Bankgiro number.

        Delegates to BankgiroNormalizer.
        """
        return FieldNormalizer._bankgiro.normalize(value)

    @staticmethod
    def normalize_plusgiro(value: str) -> list[str]:
        """
        Normalize Plusgiro number.

        Delegates to PlusgiroNormalizer.
        """
        return FieldNormalizer._plusgiro.normalize(value)

    @staticmethod
    def normalize_organisation_number(value: str) -> list[str]:
        """
        Normalize Swedish organisation number and generate VAT number variants.

        Delegates to OrganisationNumberNormalizer.
        """
        return FieldNormalizer._organisation_number.normalize(value)

    @staticmethod
    def normalize_supplier_accounts(value: str) -> list[str]:
        """
        Normalize supplier accounts field.

        Delegates to SupplierAccountsNormalizer.
        """
        return FieldNormalizer._supplier_accounts.normalize(value)

    @staticmethod
    def normalize_customer_number(value: str) -> list[str]:
        """
        Normalize customer number.

        Delegates to CustomerNumberNormalizer.
        """
        return FieldNormalizer._customer_number.normalize(value)

    @staticmethod
    def normalize_amount(value: str) -> list[str]:
        """
        Normalize monetary amount.

        Delegates to AmountNormalizer.
        """
        return FieldNormalizer._amount.normalize(value)

    @staticmethod
    def normalize_date(value: str) -> list[str]:
        """
        Normalize date to YYYY-MM-DD and generate variants.

        Delegates to DateNormalizer.
        """
        return FieldNormalizer._date.normalize(value)


# Field type to normalizer mapping
NORMALIZERS: dict[str, Callable[[str], list[str]]] = {
    'InvoiceNumber': FieldNormalizer.normalize_invoice_number,
    'OCR': FieldNormalizer.normalize_ocr_number,
    'Bankgiro': FieldNormalizer.normalize_bankgiro,
    'Plusgiro': FieldNormalizer.normalize_plusgiro,
    'Amount': FieldNormalizer.normalize_amount,
    'InvoiceDate': FieldNormalizer.normalize_date,
    'InvoiceDueDate': FieldNormalizer.normalize_date,
    'supplier_organisation_number': FieldNormalizer.normalize_organisation_number,
    'supplier_accounts': FieldNormalizer.normalize_supplier_accounts,
    'customer_number': FieldNormalizer.normalize_customer_number,
}


def normalize_field(field_name: str, value: str) -> list[str]:
    """
    Normalize a field value based on its type.

    Args:
        field_name: Name of the field (e.g., 'InvoiceNumber', 'Amount')
        value: Raw value to normalize

    Returns:
        List of normalized variants
    """
    if value is None or (isinstance(value, str) and not value.strip()):
        return []

    value = str(value)
    normalizer = NORMALIZERS.get(field_name)

    if normalizer:
        return normalizer(value)

    # Default: just clean the text
    return [FieldNormalizer.clean_text(value)]