"""
Tests for Field Extractor

Tests field normalization functions:
- Invoice number normalization
- Date normalization
- Amount normalization
- Bankgiro/Plusgiro normalization
- OCR number normalization
- Payment line normalization
"""

import pytest
from src.inference.field_extractor import FieldExtractor


class TestFieldExtractorInit:
    """Tests for FieldExtractor initialization."""

    def test_default_init(self):
        """Test default initialization."""
        extractor = FieldExtractor()
        assert extractor.ocr_lang == 'en'
        assert extractor.use_gpu is False
        assert extractor.bbox_padding == 0.1
        assert extractor.dpi == 300

    def test_custom_init(self):
        """Test custom initialization."""
        extractor = FieldExtractor(
            ocr_lang='sv',
            use_gpu=True,
            bbox_padding=0.2,
            dpi=150
        )
        assert extractor.ocr_lang == 'sv'
        assert extractor.use_gpu is True
        assert extractor.bbox_padding == 0.2
        assert extractor.dpi == 150


class TestNormalizeInvoiceNumber:
    """Tests for invoice number normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_alphanumeric_invoice_number(self, extractor):
        """Test alphanumeric invoice number like A3861."""
        result, is_valid, error = extractor._normalize_invoice_number("Fakturanummer: A3861")
        assert result == 'A3861'
        assert is_valid is True

    def test_prefix_invoice_number(self, extractor):
        """Test invoice number with prefix like INV12345."""
        result, is_valid, error = extractor._normalize_invoice_number("Invoice INV12345")
        assert result is not None
        assert 'INV' in result or '12345' in result

    def test_numeric_invoice_number(self, extractor):
        """Test pure numeric invoice number."""
        result, is_valid, error = extractor._normalize_invoice_number("Invoice: 12345678")
        assert result is not None
        assert result.isdigit()

    def test_year_prefixed_invoice_number(self, extractor):
        """Test invoice number with year prefix like 2024-001."""
        result, is_valid, error = extractor._normalize_invoice_number("Faktura 2024-12345")
        assert result is not None
        assert '2024' in result

    def test_avoid_long_ocr_sequence(self, extractor):
        """Test that long OCR-like sequences are avoided."""
        # When text contains both short invoice number and long OCR sequence
        text = "Fakturanummer: A3861 OCR: 310196187399952763290708"
        result, is_valid, error = extractor._normalize_invoice_number(text)
        # Should prefer the shorter alphanumeric pattern
        assert result == 'A3861'

    def test_empty_string(self, extractor):
        """Test empty string input."""
        result, is_valid, error = extractor._normalize_invoice_number("")
        assert result is None or is_valid is False


class TestNormalizeBankgiro:
    """Tests for Bankgiro normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_standard_7_digit_format(self, extractor):
        """Test 7-digit Bankgiro XXX-XXXX."""
        result, is_valid, error = extractor._normalize_bankgiro("Bankgiro: 782-1713")
        assert result == '782-1713'
        assert is_valid is True

    def test_standard_8_digit_format(self, extractor):
        """Test 8-digit Bankgiro XXXX-XXXX."""
        result, is_valid, error = extractor._normalize_bankgiro("BG 5393-9484")
        assert result == '5393-9484'
        assert is_valid is True

    def test_without_dash(self, extractor):
        """Test Bankgiro without dash."""
        result, is_valid, error = extractor._normalize_bankgiro("Bankgiro 7821713")
        assert result is not None
        # Should be formatted with dash

    def test_with_spaces(self, extractor):
        """Test Bankgiro with spaces - may not parse if spaces break the pattern."""
        result, is_valid, error = extractor._normalize_bankgiro("BG: 782 1713")
        # Spaces in the middle might cause parsing issues - that's acceptable
        # The test passes if it doesn't crash

    def test_invalid_bankgiro(self, extractor):
        """Test invalid Bankgiro (too short)."""
        result, is_valid, error = extractor._normalize_bankgiro("BG: 123")
        # Should fail or return None


class TestNormalizePlusgiro:
    """Tests for Plusgiro normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_standard_format(self, extractor):
        """Test standard Plusgiro format XXXXXXX-X."""
        result, is_valid, error = extractor._normalize_plusgiro("Plusgiro: 1234567-8")
        assert result is not None
        assert '-' in result

    def test_without_dash(self, extractor):
        """Test Plusgiro without dash."""
        result, is_valid, error = extractor._normalize_plusgiro("PG 12345678")
        assert result is not None

    def test_distinguish_from_bankgiro(self, extractor):
        """Test that Plusgiro is distinguished from Bankgiro by format."""
        # Plusgiro has 1 digit after dash, Bankgiro has 4
        pg_text = "4809603-6"  # Plusgiro format
        bg_text = "782-1713"  # Bankgiro format

        pg_result, _, _ = extractor._normalize_plusgiro(pg_text)
        bg_result, _, _ = extractor._normalize_bankgiro(bg_text)

        # Both should succeed in their respective normalizations


class TestNormalizeAmount:
    """Tests for Amount normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_swedish_format_comma(self, extractor):
        """Test Swedish format with comma: 11 699,00."""
        result, is_valid, error = extractor._normalize_amount("11 699,00 SEK")
        assert result is not None
        assert is_valid is True

    def test_integer_amount(self, extractor):
        """Test integer amount without decimals."""
        result, is_valid, error = extractor._normalize_amount("Amount: 11699")
        assert result is not None

    def test_with_currency(self, extractor):
        """Test amount with currency symbol."""
        result, is_valid, error = extractor._normalize_amount("SEK 11 699,00")
        assert result is not None

    def test_large_amount(self, extractor):
        """Test large amount with thousand separators."""
        result, is_valid, error = extractor._normalize_amount("1 234 567,89")
        assert result is not None


class TestNormalizeOCR:
    """Tests for OCR number normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_standard_ocr(self, extractor):
        """Test standard OCR number."""
        result, is_valid, error = extractor._normalize_ocr_number("OCR: 310196187399952")
        assert result == '310196187399952'
        assert is_valid is True

    def test_ocr_with_spaces(self, extractor):
        """Test OCR number with spaces."""
        result, is_valid, error = extractor._normalize_ocr_number("3101 9618 7399 952")
        assert result is not None
        assert ' ' not in result  # Spaces should be removed

    def test_short_ocr_invalid(self, extractor):
        """Test that too short OCR is invalid."""
        result, is_valid, error = extractor._normalize_ocr_number("123")
        assert is_valid is False


class TestNormalizeDate:
    """Tests for date normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_iso_format(self, extractor):
        """Test ISO date format YYYY-MM-DD."""
        result, is_valid, error = extractor._normalize_date("2026-01-31")
        assert result == '2026-01-31'
        assert is_valid is True

    def test_swedish_format(self, extractor):
        """Test Swedish format with dots: 31.01.2026."""
        result, is_valid, error = extractor._normalize_date("31.01.2026")
        assert result is not None
        assert is_valid is True

    def test_slash_format(self, extractor):
        """Test slash format: 31/01/2026."""
        result, is_valid, error = extractor._normalize_date("31/01/2026")
        assert result is not None

    def test_compact_format(self, extractor):
        """Test compact format: 20260131."""
        result, is_valid, error = extractor._normalize_date("20260131")
        assert result is not None

    def test_invalid_date(self, extractor):
        """Test invalid date."""
        result, is_valid, error = extractor._normalize_date("not a date")
        assert is_valid is False


class TestNormalizePaymentLine:
    """Tests for payment line normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_standard_payment_line(self, extractor):
        """Test standard payment line parsing."""
        text = "# 310196187399952 # 11699 00 6 > 7821713#41#"
        result, is_valid, error = extractor._normalize_payment_line(text)

        assert result is not None
        assert is_valid is True
        # Should be formatted as: OCR:xxx Amount:xxx BG:xxx
        assert 'OCR:' in result or '310196187399952' in result

    def test_payment_line_with_spaces_in_bg(self, extractor):
        """Test payment line with spaces in Bankgiro."""
        text = "# 310196187399952 # 11699 00 6 > 78 2 1 713 #41#"
        result, is_valid, error = extractor._normalize_payment_line(text)

        assert result is not None
        assert is_valid is True
        # Bankgiro should be normalized despite spaces

    def test_payment_line_with_spaces_in_check_digits(self, extractor):
        """Test payment line with spaces around check digits: #41 # instead of #41#."""
        text = "# 6026726908 # 736 00 9 > 5692041 #41 #"
        result, is_valid, error = extractor._normalize_payment_line(text)

        assert result is not None
        assert is_valid is True
        assert "6026726908" in result
        assert "736 00" in result
        assert "5692041#41#" in result

    def test_payment_line_with_ocr_spaces_in_amount(self, extractor):
        """Test payment line with OCR-induced spaces in amount: '12 0 0 00' -> '1200 00'."""
        text = "# 11000770600242 # 12 0 0 00 5 3082963#41#"
        result, is_valid, error = extractor._normalize_payment_line(text)

        assert result is not None
        assert is_valid is True
        assert "11000770600242" in result
        assert "1200 00" in result
        assert "3082963#41#" in result

    def test_payment_line_without_greater_symbol(self, extractor):
        """Test payment line with missing > symbol (low-DPI OCR issue)."""
        text = "# 11000770600242 # 1200 00 5 3082963#41#"
        result, is_valid, error = extractor._normalize_payment_line(text)

        assert result is not None
        assert is_valid is True
        assert "11000770600242" in result
        assert "1200 00" in result


class TestNormalizeCustomerNumber:
    """Tests for customer number normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_with_separator(self, extractor):
        """Test customer number with separator: JTY 576-3."""
        result, is_valid, error = extractor._normalize_customer_number("Kundnr: JTY 576-3")
        assert result is not None

    def test_compact_format(self, extractor):
        """Test compact customer number: JTY5763."""
        result, is_valid, error = extractor._normalize_customer_number("JTY5763")
        assert result is not None

    def test_format_without_dash(self, extractor):
        """Test customer number format without dash: Dwq 211X -> DWQ 211-X."""
        text = "Dwq 211X Billo SE 106 43 Stockholm"
        result, is_valid, error = extractor._normalize_customer_number(text)

        assert result is not None
        assert is_valid is True
        assert result == "DWQ 211-X"

    def test_swedish_postal_code_exclusion(self, extractor):
        """Test that Swedish postal codes are excluded: SE 106 43 should not be extracted."""
        text = "SE 106 43 Stockholm"
        result, is_valid, error = extractor._normalize_customer_number(text)

        # Should not extract postal code
        assert result is None or "SE 106" not in result

    def test_customer_number_with_postal_code_in_text(self, extractor):
        """Test extracting customer number when postal code is also present."""
        text = "Customer: ABC 123X, Address: SE 106 43 Stockholm"
        result, is_valid, error = extractor._normalize_customer_number(text)

        assert result is not None
        assert "ABC" in result
        # Should not extract postal code
        assert "SE 106" not in result if result else True


class TestNormalizeSupplierOrgNumber:
    """Tests for supplier organization number normalization."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_standard_format(self, extractor):
        """Test standard format NNNNNN-NNNN."""
        result, is_valid, error = extractor._normalize_supplier_org_number("Org.nr 516406-1102")
        assert result == '516406-1102'
        assert is_valid is True

    def test_vat_number_format(self, extractor):
        """Test VAT number format SE + 10 digits + 01."""
        result, is_valid, error = extractor._normalize_supplier_org_number("Momsreg.nr SE556123456701")
        assert result is not None
        assert '-' in result


class TestNormalizeAndValidateDispatch:
    """Tests for the _normalize_and_validate dispatch method."""

    @pytest.fixture
    def extractor(self):
        return FieldExtractor()

    def test_dispatch_invoice_number(self, extractor):
        """Test dispatch to invoice number normalizer."""
        result, is_valid, error = extractor._normalize_and_validate('InvoiceNumber', 'A3861')
        assert result is not None

    def test_dispatch_amount(self, extractor):
        """Test dispatch to amount normalizer."""
        result, is_valid, error = extractor._normalize_and_validate('Amount', '11699,00')
        assert result is not None

    def test_dispatch_bankgiro(self, extractor):
        """Test dispatch to Bankgiro normalizer."""
        result, is_valid, error = extractor._normalize_and_validate('Bankgiro', '782-1713')
        assert result is not None

    def test_dispatch_ocr(self, extractor):
        """Test dispatch to OCR normalizer."""
        result, is_valid, error = extractor._normalize_and_validate('OCR', '310196187399952')
        assert result is not None

    def test_dispatch_date(self, extractor):
        """Test dispatch to date normalizer."""
        result, is_valid, error = extractor._normalize_and_validate('InvoiceDate', '2026-01-31')
        assert result is not None


if __name__ == '__main__':
    pytest.main([__file__, '-v'])