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> Index of every page on this site: [llms.txt](https://quittio.dev/llms.txt)

[API reference](https://quittio.dev/docs/api)

# Quittio\\Core

## quittio/core \#

### [Quittio\\Core](https://quittio.dev/docs/api/Quittio/Core)

- [`Config`](https://quittio.dev/docs/api/Quittio/Core/Config)Configuration of the core without Laravel. The Laravel package translates config/quittio.php into it (Quittio\\Laravel\\Support\\ConfigMapper), whose layout differs from the keys of fromArray().
- [`Quittio`](https://quittio.dev/docs/api/Quittio/Core/Quittio)Entry point without Laravel:

### [Quittio\\Core\\Builder](https://quittio.dev/docs/api/Quittio/Core/Builder)

- [`InvoiceBuilder`](https://quittio.dev/docs/api/Quittio/Core/Builder/InvoiceBuilder)Fluent builder for InvoiceData.
- [`Line`](https://quittio.dev/docs/api/Quittio/Core/Builder/Line)Starts an invoice line for InvoiceBuilder::line() and lines() without a callback: ->line(Line::make('Consulting', netPrice: '120.00')->sellerId('C-1')). Simple lines need no builder: ->line('Consulting', netPrice: '120.00', quantity: 4, unit: UnitCode::Hour).
- [`LineBuilder`](https://quittio.dev/docs/api/Quittio/Core/Builder/LineBuilder)Fluent builder for an invoice line (BG-25).
- [`Party`](https://quittio.dev/docs/api/Quittio/Core/Builder/Party)Starts a seller or buyer for InvoiceBuilder::seller() and buyer() without a callback: ->buyer(Party::make('Kunde AG')->vatId('DE987654321')->address('Weg 1', '54321', 'Beispielstadt', 'DE')).
- [`PartyBuilder`](https://quittio.dev/docs/api/Quittio/Core/Builder/PartyBuilder)Fluent builder for the seller (BG-4), the buyer (BG-7) and the payee (BG-10).
- [`PaymentTermsBuilder`](https://quittio.dev/docs/api/Quittio/Core/Builder/PaymentTermsBuilder)Fluent builder for structured payment terms (BT-20, BT-9).

### [Quittio\\Core\\Builder\\Concerns](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns)

- [`BuildsAllowancesAndCharges`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsAllowancesAndCharges) traitDocument level allowances and charges (BG-20, BG-21) and discounts split over the VAT rates.
- [`BuildsDelivery`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsDelivery) traitDelivery information (BG-13) and the invoicing period (BG-14).
- [`BuildsExtensions`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsExtensions) traitData of the EXTENDED profile and of the XRechnung extension.
- [`BuildsHeader`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsHeader) traitInvoice number, dates, type, currencies, business process and standard version.
- [`BuildsLines`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsLines) traitInvoice lines (BG-25) and their groups.
- [`BuildsNotesAndAttachments`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsNotesAndAttachments) traitInvoice notes (BG-1) and supporting documents (BG-24).
- [`BuildsParties`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsParties) traitSeller, buyer, payee and tax representative (BG-4, BG-7, BG-10, BG-11).
- [`BuildsPayment`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsPayment) traitPayment instructions (BG-16 to BG-19), payment terms and the prepaid and rounding amounts (BT-113, BT-114).
- [`BuildsPresentationAndMeta`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsPresentationAndMeta) traitPresentation, locale, time zone, custom values, flags and the source of the invoice.
- [`BuildsReferences`](https://quittio.dev/docs/api/Quittio/Core/Builder/Concerns/BuildsReferences) traitDocument references (BT-10 to BT-19, BG-3) and the invoiced object.

### [Quittio\\Core\\Calculation](https://quittio.dev/docs/api/Quittio/Core/Calculation)

- [`AllowanceSplitter`](https://quittio.dev/docs/api/Quittio/Core/Calculation/AllowanceSplitter)Splits a document discount over several VAT groups.
- [`CalculationException`](https://quittio.dev/docs/api/Quittio/Core/Calculation/CalculationException)
- [`CalculationPolicy`](https://quittio.dev/docs/api/Quittio/Core/Calculation/CalculationPolicy)Decisions of the calculator that are not fixed by EN 16931. The policy is configuration of the run and not stored with the invoice: the same data calculated under another policy can give other amounts.
- [`DeclaredAmounts`](https://quittio.dev/docs/api/Quittio/Core/Calculation/DeclaredAmounts)Declared amounts of an existing document (Meta::FLAG\_DECLARED\_AMOUNTS): whether they are needed at all, and the fingerprint of the amount inputs they belong to.
- [`DeclaredAmountsMode`](https://quittio.dev/docs/api/Quittio/Core/Calculation/DeclaredAmountsMode) enumWhat the calculator does with the declared amounts of an existing document (line net amounts BT-131 and VAT breakdown BT-116, BT-117 that another system rounded differently, see Meta::FLAG\_DECLARED\_AMOUNTS).
- [`En16931Calculator`](https://quittio.dev/docs/api/Quittio/Core/Calculation/En16931Calculator)Calculation according to EN 16931.
- [`GrossPriceConverter`](https://quittio.dev/docs/api/Quittio/Core/Calculation/GrossPriceConverter)Gross price mode for B2C and shops.
- [`LargestRemainder`](https://quittio.dev/docs/api/Quittio/Core/Calculation/LargestRemainder)Distributes an amount over weights so that the rounded parts add up exactly (largest remainder method).
- [`LineCalculator`](https://quittio.dev/docs/api/Quittio/Core/Calculation/LineCalculator)Calculates the invoice line net amount (BT-131):
- [`TotalsCalculator`](https://quittio.dev/docs/api/Quittio/Core/Calculation/TotalsCalculator) interfaceCalculates line amounts, allowances and charges, the VAT breakdown and totals.

### [Quittio\\Core\\Codes](https://quittio.dev/docs/api/Quittio/Core/Codes)

- [`CodeList`](https://quittio.dev/docs/api/Quittio/Core/Codes/CodeList)Access to the official code lists generated from the EN 16931 rules and, for Peppol, the Peppol BIS rules (resources/codelists/\*.json, see tools/codelists/update.php).
- [`CodeListGenerator`](https://quittio.dev/docs/api/Quittio/Core/Codes/CodeListGenerator)Generates the code list files (resources/codelists/\*.json) from the official EN 16931 Schematron rules (BR-CL-\*), as shipped with the KoSIT validator configuration, and the narrower Peppol lists from the Peppol BIS Schematron.
- [`RawCode`](https://quittio.dev/docs/api/Quittio/Core/Codes/RawCode)A code that is not (yet) part of the code list enums shipped with the package.

### [Quittio\\Core\\Contracts](https://quittio.dev/docs/api/Quittio/Core/Contracts)

- [`ProvidesInvoiceData`](https://quittio.dev/docs/api/Quittio/Core/Contracts/ProvidesInvoiceData) interfaceImplemented by application models that can be turned into an invoice (e.g. an order).
- [`ProvidesInvoiceLine`](https://quittio.dev/docs/api/Quittio/Core/Contracts/ProvidesInvoiceLine) interfaceImplemented by application models that describe an invoice line (e.g. an order item).
- [`ProvidesParty`](https://quittio.dev/docs/api/Quittio/Core/Contracts/ProvidesParty) interfaceImplemented by application models that describe a trade party (e.g. a customer).

### [Quittio\\Core\\Corrections](https://quittio.dev/docs/api/Quittio/Core/Corrections)

- [`Cancellation`](https://quittio.dev/docs/api/Quittio/Core/Corrections/Cancellation)Full cancellation of an issued invoice: a new invoice with its own number that reverses the original and refers to it (BG-3).
- [`CancellationHistory`](https://quittio.dev/docs/api/Quittio/Core/Corrections/CancellationHistory)What the earlier partial cancellations of an invoice cancelled per VAT group (category and rate), so that the VAT of the next partial cancellation is rounded cumulatively.
- [`Correction`](https://quittio.dev/docs/api/Quittio/Core/Corrections/Correction)Corrected invoice (type code 384) that replaces an issued invoice: a copy of the original with its own number, the reference to the original (BG-3) and the note "Diese Rechnung berichtigt und ersetzt die Rechnung … vom …" (BT-22), so that it states by a specific and unambiguous reference that it corrects the original (section 31 (5) UStDV, section 15.2a (7) UStAE). Change what was wrong on the returned builder.
- [`PriceReduction`](https://quittio.dev/docs/api/Quittio/Core/Corrections/PriceReduction)Document on a reduction of the consideration of an issued invoice (section 17 UStG), e.g. a cash discount taken, a reduction because of a complaint about defects or a bonus: a credit note (type code 381, positive amounts) with one line per VAT group of the original, the reference to the original (BG-3) and a note that names the reduction of the net amount and of the VAT per rate (BT-22), titled "Entgeltminderung" in Germany.
- [`PriceReductionReason`](https://quittio.dev/docs/api/Quittio/Core/Corrections/PriceReductionReason) enumWhy the consideration of an invoice was reduced (PriceReduction); the note names it.

### [Quittio\\Core\\Countries](https://quittio.dev/docs/api/Quittio/Core/Countries)

- [`AbstractCountryPack`](https://quittio.dev/docs/api/Quittio/Core/Countries/AbstractCountryPack)Base class with neutral defaults, so that country packs only override what differs.
- [`CorrectionPolicy`](https://quittio.dev/docs/api/Quittio/Core/Countries/CorrectionPolicy)Default handling of cancellations and corrections in a country, and the titles of these documents. Quittio::cancellation() takes the cancellation strategy and the titles "cancellation" and "cancellation\_self\_billed"; Quittio::correction() the title "correction", Quittio::priceReduction() the title "price\_reduction"; the title "self\_billed" is the title of self-billed invoices in PDF and HTML (InvoiceTitle::policyTitle()); the Managed layer takes the correction strategy.
- [`CountryDefaults`](https://quittio.dev/docs/api/Quittio/Core/Countries/CountryDefaults)Defaults of a country.
- [`CountryGeneric`](https://quittio.dev/docs/api/Quittio/Core/Countries/CountryGeneric)Neutral pack for countries without an installed country pack: EN 16931 rules only and international formatting. A warning is issued when an invoice is validated with this pack.
- [`CountryPack`](https://quittio.dev/docs/api/Quittio/Core/Countries/CountryPack) interfaceEverything that differs between countries.
- [`CountryRegistry`](https://quittio.dev/docs/api/Quittio/Core/Countries/CountryRegistry)Installed country packs.
- [`CountryResolver`](https://quittio.dev/docs/api/Quittio/Core/Countries/CountryResolver) interfaceSelects the country packs for an invoice.
- [`DefaultCountryResolver`](https://quittio.dev/docs/api/Quittio/Core/Countries/DefaultCountryResolver)The seller's country (BT-40) determines the leading pack. The buyer's country (BT-55) adds rules for cross-border invoices. A country without a pack of its own takes the pack of the country whose VAT territory it belongs to (VatTerritory::vatCountry(): Monaco the French, Liechtenstein the Swiss pack). Without an installed pack, a generic pack is used.
- [`DunningLaw`](https://quittio.dev/docs/api/Quittio/Core/Countries/DunningLaw)Statutory late payment rules (EU late payment directive plus national law). Amounts and percentage points are decimal strings.
- [`Exporter`](https://quittio.dev/docs/api/Quittio/Core/Countries/Exporter) interfaceCountry specific export format (e.g. DATEV for Germany, FEC for France). Country packs only declare which exporters they provide (CountryPack::exporters()); Quittio runs none of them, applications may.
- [`LegalTextCatalog`](https://quittio.dev/docs/api/Quittio/Core/Countries/LegalTextCatalog)Legal and informational texts of a country pack per locale.
- [`MandatoryField`](https://quittio.dev/docs/api/Quittio/Core/Countries/MandatoryField)A value that must appear in the PDF (checked by the mandatory field guard).
- [`MandatoryFieldList`](https://quittio.dev/docs/api/Quittio/Core/Countries/MandatoryFieldList)Values that must be output in the PDF for one invoice.
- [`NumberingRules`](https://quittio.dev/docs/api/Quittio/Core/Countries/NumberingRules)Requirements for invoice numbering in a country. The Managed layer applies the default pattern, the default reset and the allowed resets.
- [`ResolvedCountries`](https://quittio.dev/docs/api/Quittio/Core/Countries/ResolvedCountries)Leading pack (seller side) and, for cross-border invoices, the buyer's pack.
- [`RetentionRule`](https://quittio.dev/docs/api/Quittio/Core/Countries/RetentionRule)Retention period for invoices.
- [`VatTerritory`](https://quittio.dev/docs/api/Quittio/Core/Countries/VatTerritory)The EU VAT territory (Art. 5 to 7 of Directive 2006/112/EC) as far as it can be told from a country code and a postcode.

### [Quittio\\Core\\Countries\\Capabilities](https://quittio.dev/docs/api/Quittio/Core/Countries/Capabilities)

- [`CompletesInvoices`](https://quittio.dev/docs/api/Quittio/Core/Countries/Capabilities/CompletesInvoices) interfaceA country pack that completes an invoice before it is calculated, validated and rendered, e.g. with a notice the law of the country expects for some buyers. The render pipeline calls it for the leading pack of the invoice; what it adds is part of the rendered data.
- [`ProvidesFormats`](https://quittio.dev/docs/api/Quittio/Core/Countries/Capabilities/ProvidesFormats) interfaceA country pack that brings output formats, e.g. a national e-invoice format, with their aliases and the serializers of their syntaxes. Quittio::registerCountry() registers them. AbstractCountryPack implements it with empty defaults.
- [`ProvidesReferenceRates`](https://quittio.dev/docs/api/Quittio/Core/Countries/Capabilities/ProvidesReferenceRates) interfaceA country pack whose late payment law has a reference interest rate, so that Dunning\\DefaultInterest::forCountry() calculates default interest for it.

### [Quittio\\Core\\Data](https://quittio.dev/docs/api/Quittio/Core/Data)

- [`Identifier`](https://quittio.dev/docs/api/Quittio/Core/Data/Identifier)Identifier with an optional scheme (ISO/IEC 6523 ICD or another code list depending on the field).
- [`InvoiceData`](https://quittio.dev/docs/api/Quittio/Core/Data/InvoiceData)Root of the semantic invoice model (EN 16931, superset of the 2017 and 2026 versions).
- [`Meta`](https://quittio.dev/docs/api/Quittio/Core/Data/Meta)Package-internal metadata: locale, time zone, exchange rate, free data for templates and flags for country packs.
- [`Note`](https://quittio.dev/docs/api/Quittio/Core/Data/Note)Invoice note (BG-1).

### [Quittio\\Core\\Data\\AllowanceCharge](https://quittio.dev/docs/api/Quittio/Core/Data/AllowanceCharge)

- [`DocumentAllowance`](https://quittio.dev/docs/api/Quittio/Core/Data/AllowanceCharge/DocumentAllowance)Document level allowance (BG-20). An allowance has exactly one VAT category and rate.
- [`DocumentAllowanceCharge`](https://quittio.dev/docs/api/Quittio/Core/Data/AllowanceCharge/DocumentAllowanceCharge)Common structure of document level allowances (BG-20) and charges (BG-21).
- [`DocumentCharge`](https://quittio.dev/docs/api/Quittio/Core/Data/AllowanceCharge/DocumentCharge)Document level charge (BG-21).
- [`LineAllowance`](https://quittio.dev/docs/api/Quittio/Core/Data/AllowanceCharge/LineAllowance)Invoice line allowance (BG-27).
- [`LineAllowanceCharge`](https://quittio.dev/docs/api/Quittio/Core/Data/AllowanceCharge/LineAllowanceCharge)Common structure of invoice line allowances (BG-27) and charges (BG-28). Line allowances and charges have no VAT category of their own; they inherit the line's category.
- [`LineCharge`](https://quittio.dev/docs/api/Quittio/Core/Data/AllowanceCharge/LineCharge)Invoice line charge (BG-28).

### [Quittio\\Core\\Data\\Attachments](https://quittio.dev/docs/api/Quittio/Core/Data/Attachments)

- [`Attachment`](https://quittio.dev/docs/api/Quittio/Core/Data/Attachments/Attachment)Additional supporting document (BG-24).

### [Quittio\\Core\\Data\\Concerns](https://quittio.dev/docs/api/Quittio/Core/Data/Concerns)

- [`Immutable`](https://quittio.dev/docs/api/Quittio/Core/Data/Concerns/Immutable) traitGeneric copy-on-write helper for readonly DTOs whose properties are all promoted constructor parameters.

### [Quittio\\Core\\Data\\Delivery](https://quittio.dev/docs/api/Quittio/Core/Data/Delivery)

- [`Delivery`](https://quittio.dev/docs/api/Quittio/Core/Data/Delivery/Delivery)Delivery information (BG-13).
- [`Period`](https://quittio.dev/docs/api/Quittio/Core/Data/Delivery/Period)Invoicing period (BG-14: BT-73, BT-74) or invoice line period (BG-26: BT-134, BT-135). At least one of start or end must be set; the end must not lie before the start.

### [Quittio\\Core\\Data\\Extensions](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions)

- [`ExtendedData`](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions/ExtendedData)Document level data that exists only in the Factur-X/ZUGFeRD EXTENDED profile. The selection covers the practically relevant elements.
- [`ExtendedParty`](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions/ExtendedParty)Additional trade party of profile EXTENDED (invoicer, invoicee, ultimate customer, ship-from, line ship-to).
- [`IncludedProduct`](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions/IncludedProduct)Component of a set or bundle (profile EXTENDED).
- [`Installment`](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions/Installment)One of several payment terms with its own due date (profile EXTENDED), e.g. instalments.
- [`LineExtendedData`](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions/LineExtendedData)Line level data that exists only in the Factur-X/ZUGFeRD EXTENDED profile.
- [`ThirdPartyPayment`](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions/ThirdPartyPayment)Amount collected on behalf of a third party (XRechnung extension, group BG-DEX-09). It is added to the amount due (BR-DEX-09).
- [`XRechnungExtensionData`](https://quittio.dev/docs/api/Quittio/Core/Data/Extensions/XRechnungExtensionData)Data of the XRechnung extension. Sub invoice lines are modelled via InvoiceLine::$subLines.

### [Quittio\\Core\\Data\\Lines](https://quittio.dev/docs/api/Quittio/Core/Data/Lines)

- [`Classification`](https://quittio.dev/docs/api/Quittio/Core/Data/Lines/Classification)Item classification identifier (BT-158) with scheme (BT-158-1) and scheme version (BT-158-2), e.g. eCl@ss, UNSPSC, CPV or customs tariff numbers.
- [`InvoiceLine`](https://quittio.dev/docs/api/Quittio/Core/Data/Lines/InvoiceLine)Invoice line (BG-25).
- [`Item`](https://quittio.dev/docs/api/Quittio/Core/Data/Lines/Item)Item information (BG-31).
- [`ItemAttribute`](https://quittio.dev/docs/api/Quittio/Core/Data/Lines/ItemAttribute)Item attribute (BG-32), e.g. colour, size, vehicle identification number.
- [`LineVat`](https://quittio.dev/docs/api/Quittio/Core/Data/Lines/LineVat)Line VAT information (BG-30).
- [`Price`](https://quittio.dev/docs/api/Quittio/Core/Data/Lines/Price)Price details (BG-29). Prices may have more than two decimals.

### [Quittio\\Core\\Data\\Party](https://quittio.dev/docs/api/Quittio/Core/Data/Party)

- [`Address`](https://quittio.dev/docs/api/Quittio/Core/Data/Party/Address)Postal address (BG-5 seller, BG-8 buyer, BG-12 tax representative, BG-15 deliver to).
- [`BuyerParty`](https://quittio.dev/docs/api/Quittio/Core/Data/Party/BuyerParty)Buyer (BG-7).
- [`Contact`](https://quittio.dev/docs/api/Quittio/Core/Data/Party/Contact)Contact (BG-6 seller: BT-41/42/43, BG-9 buyer: BT-56/57/58).
- [`ElectronicAddress`](https://quittio.dev/docs/api/Quittio/Core/Data/Party/ElectronicAddress)Electronic address (BT-34 seller, BT-49 buyer) with its EAS scheme. For Peppol, the electronic address is also the participant identifier.
- [`PayeeParty`](https://quittio.dev/docs/api/Quittio/Core/Data/Party/PayeeParty)Payee (BG-10), only when different from the seller (factoring, collection, group company).
- [`SellerParty`](https://quittio.dev/docs/api/Quittio/Core/Data/Party/SellerParty)Seller (BG-4).
- [`TaxRepresentativeParty`](https://quittio.dev/docs/api/Quittio/Core/Data/Party/TaxRepresentativeParty)Seller tax representative (BG-11).

### [Quittio\\Core\\Data\\Payment](https://quittio.dev/docs/api/Quittio/Core/Data/Payment)

- [`CashDiscount`](https://quittio.dev/docs/api/Quittio/Core/Data/Payment/CashDiscount)Cash discount ("Skonto") granted for payment within $days days.
- [`CreditTransfer`](https://quittio.dev/docs/api/Quittio/Core/Data/Payment/CreditTransfer)Credit transfer (BG-17).
- [`DirectDebit`](https://quittio.dev/docs/api/Quittio/Core/Data/Payment/DirectDebit)Direct debit (BG-19).
- [`PaymentCard`](https://quittio.dev/docs/api/Quittio/Core/Data/Payment/PaymentCard)Payment card information (BG-18). Only the last 4 to 6 digits of the card number may be stored.
- [`PaymentInstructions`](https://quittio.dev/docs/api/Quittio/Core/Data/Payment/PaymentInstructions)Payment instructions (BG-16).
- [`PaymentTerms`](https://quittio.dev/docs/api/Quittio/Core/Data/Payment/PaymentTerms)Structured payment terms. Serialised into BT-20 text (and structured elements where the profile allows).
- [`PenaltyTerms`](https://quittio.dev/docs/api/Quittio/Core/Data/Payment/PenaltyTerms)Late payment terms. Structured only in profile EXTENDED, otherwise rendered as text.

### [Quittio\\Core\\Data\\Presentation](https://quittio.dev/docs/api/Quittio/Core/Data/Presentation)

- [`Colors`](https://quittio.dev/docs/api/Quittio/Core/Data/Presentation/Colors)Colours used by the PDF template.
- [`LineGroup`](https://quittio.dev/docs/api/Quittio/Core/Data/Presentation/LineGroup)Group of invoice lines with an optional subtotal. Presentation only.
- [`LinePresentation`](https://quittio.dev/docs/api/Quittio/Core/Data/Presentation/LinePresentation)PDF-only presentation hints for an invoice line. Never written to XML.
- [`Presentation`](https://quittio.dev/docs/api/Quittio/Core/Data/Presentation/Presentation)Data used only for the PDF. Never written to XML.

### [Quittio\\Core\\Data\\References](https://quittio.dev/docs/api/Quittio/Core/Data/References)

- [`DocumentReference`](https://quittio.dev/docs/api/Quittio/Core/Data/References/DocumentReference)Reference to a related document on line level or as additional reference (profile EXTENDED), e.g. delivery note, order, contract or receiving advice.
- [`PrecedingInvoiceReference`](https://quittio.dev/docs/api/Quittio/Core/Data/References/PrecedingInvoiceReference)Preceding invoice reference (BG-3), used for cancellations, corrections and final invoices.
- [`ProjectReference`](https://quittio.dev/docs/api/Quittio/Core/Data/References/ProjectReference)Project reference (BT-11). CII requires a name in addition to the identifier.

### [Quittio\\Core\\Data\\Totals](https://quittio.dev/docs/api/Quittio/Core/Data/Totals)

- [`Totals`](https://quittio.dev/docs/api/Quittio/Core/Data/Totals/Totals)Document totals (BG-22), calculated by the calculator.
- [`VatBreakdown`](https://quittio.dev/docs/api/Quittio/Core/Data/Totals/VatBreakdown)VAT breakdown (BG-23), one entry per combination of VAT category and rate.

### [Quittio\\Core\\Documents](https://quittio.dev/docs/api/Quittio/Core/Documents)

- [`AccountStatement`](https://quittio.dev/docs/api/Quittio/Core/Documents/AccountStatement)Account statement for a customer: open and paid invoices of a period.
- [`BonusStatement`](https://quittio.dev/docs/api/Quittio/Core/Documents/BonusStatement)Data of a bonus statement: a reduction of the consideration of all supplies of a period, e.g. an annual bonus, documented in one statement instead of one document per invoice (in Germany section 17 (4) UStG). The reduction per VAT rate is in the lines of the document.
- [`DocumentBuilder`](https://quittio.dev/docs/api/Quittio/Core/Documents/DocumentBuilder)Fluent builder for documents. Parties, lines, notes, discounts and payment data work exactly like in the {@see InvoiceBuilder}.
- [`DocumentCalculator`](https://quittio.dev/docs/api/Quittio/Core/Documents/DocumentCalculator)Calculates documents with the invoice calculator. Optional and alternative lines get their line amounts but are excluded from the totals.
- [`DocumentData`](https://quittio.dev/docs/api/Quittio/Core/Documents/DocumentData)Quote, order confirmation, delivery note, proforma invoice, payment reminder, account statement or bonus statement. Shares parties, lines and calculation with {@see InvoiceData}, but never produces e-invoice XML. Payment reminders and account statements have no lines: their amount comes from {@see Dunning} and {@see AccountStatement}.
- [`DocumentLineOptions`](https://quittio.dev/docs/api/Quittio/Core/Documents/DocumentLineOptions)Document specific line details, keyed by line identifier in {@see DocumentData}.
- [`DocumentType`](https://quittio.dev/docs/api/Quittio/Core/Documents/DocumentType) enumCommercial documents that share templates and calculation with invoices but carry no e-invoice XML.
- [`Dunning`](https://quittio.dev/docs/api/Quittio/Core/Documents/Dunning)Data of a payment reminder: open items, fees, interest and the new deadline.
- [`DunningFee`](https://quittio.dev/docs/api/Quittio/Core/Documents/DunningFee)Fee of a payment reminder (e.g. costs of the reminder, flat rate according to national law).
- [`DunningFeeKind`](https://quittio.dev/docs/api/Quittio/Core/Documents/DunningFeeKind) enumWhat a fee of a payment reminder is.
- [`InterestCharge`](https://quittio.dev/docs/api/Quittio/Core/Documents/InterestCharge)Default interest on an open amount for a period (simple interest).
- [`OpenItem`](https://quittio.dev/docs/api/Quittio/Core/Documents/OpenItem)An invoice in a payment reminder or account statement.
- [`Package`](https://quittio.dev/docs/api/Quittio/Core/Documents/Package)Package of a delivery note.

### [Quittio\\Core\\Dunning](https://quittio.dev/docs/api/Quittio/Core/Dunning)

- [`DefaultInterest`](https://quittio.dev/docs/api/Quittio/Core/Dunning/DefaultInterest)Default interest of a late payment law: the reference rate plus the points of the DunningLaw (business or consumer debtors), split at every change of the reference rate, with the day count basis of the law; a fixed rate of the law for businesses or consumers instead, if it has one. The result goes into DocumentBuilder::interestCharge().
- [`ReferenceRates`](https://quittio.dev/docs/api/Quittio/Core/Dunning/ReferenceRates) interfaceThe reference interest rate of a country's late payment law, e.g. the German Basiszinssatz (section 247 BGB) or the ECB main refinancing rate. Default interest is the reference rate plus the points of the DunningLaw.

### [Quittio\\Core\\Enums](https://quittio.dev/docs/api/Quittio/Core/Enums)

- [`AllowanceReasonCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/AllowanceReasonCode) enumAllowance reason code (BT-98, BT-140), UNTDID 5189 subset.
- [`ChargeReasonCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/ChargeReasonCode) enumCharge reason code (BT-105, BT-145), UNTDID 7161 subset. Further codes can be used as RawCode.
- [`DocumentReferenceTypeCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/DocumentReferenceTypeCode) enumDocument type code for additional supporting documents (BG-24), UNTDID 1001 subset.
- [`ElectronicAddressScheme`](https://quittio.dev/docs/api/Quittio/Core/Enums/ElectronicAddressScheme) enumElectronic address scheme (BT-34-1, BT-49-1), CEF EAS code list. Further codes can be used as RawCode.
- [`IdentifierScheme`](https://quittio.dev/docs/api/Quittio/Core/Enums/IdentifierScheme) enumIdentifier scheme (ISO/IEC 6523 ICD), e.g. for BT-29, BT-46, BT-157. Further codes can be used as RawCode.
- [`InvoiceTypeCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/InvoiceTypeCode) enumDocument type code (BT-3), UNTDID 1001 subset allowed by EN 16931.
- [`ItemClassificationScheme`](https://quittio.dev/docs/api/Quittio/Core/Enums/ItemClassificationScheme) enumItem classification scheme (BT-158-1), UNTDID 7143 subset. Further codes can be used as RawCode.
- [`MimeType`](https://quittio.dev/docs/api/Quittio/Core/Enums/MimeType) enumMIME code of an attached document (BT-125-1). Xml (application/xml) is not part of the EN 16931 code list (BR-CL-24); only the XRechnung extension allows it (BR-DEX-01).
- [`NoteSubjectCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/NoteSubjectCode) enumInvoice note subject code (BT-21), UNTDID 4451 subset. Further codes can be used as RawCode.
- [`PaymentMeansCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/PaymentMeansCode) enumPayment means type code (BT-81), UNTDID 4461. Further codes can be used as RawCode.
- [`TaxPointDateCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/TaxPointDateCode) enumValue added tax point date code (BT-8).
- [`UnitCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/UnitCode) enumUnit of measure (BT-130, BT-150), UN/ECE Recommendation 20 and 21. Further codes can be used as RawCode.
- [`VatCategory`](https://quittio.dev/docs/api/Quittio/Core/Enums/VatCategory) enumVAT category code (BT-95, BT-102, BT-118, BT-151), UNTDID 5305 subset.
- [`VatExemptionReasonCode`](https://quittio.dev/docs/api/Quittio/Core/Enums/VatExemptionReasonCode) enumVAT exemption reason code (BT-121), VATEX code list. Further codes can be used as RawCode.

### [Quittio\\Core\\Enums\\Concerns](https://quittio.dev/docs/api/Quittio/Core/Enums/Concerns)

- [`HasLabel`](https://quittio.dev/docs/api/Quittio/Core/Enums/Concerns/HasLabel) traitTranslated labels for code list enums, e.g. "Stunde" for HUR.

### [Quittio\\Core\\Exceptions](https://quittio.dev/docs/api/Quittio/Core/Exceptions)

- [`ConfigurationException`](https://quittio.dev/docs/api/Quittio/Core/Exceptions/ConfigurationException)Invalid configuration or an unsupported combination of format and profile.
- [`HydrationException`](https://quittio.dev/docs/api/Quittio/Core/Exceptions/HydrationException)Array or JSON input does not match the invoice data model.
- [`InvalidArgumentException`](https://quittio.dev/docs/api/Quittio/Core/Exceptions/InvalidArgumentException)\\InvalidArgumentException thrown by Quittio; catch QuittioException for every error of the library.
- [`InvalidInvoiceData`](https://quittio.dev/docs/api/Quittio/Core/Exceptions/InvalidInvoiceData)Builder or data input is structurally incomplete.
- [`LogicException`](https://quittio.dev/docs/api/Quittio/Core/Exceptions/LogicException)\\LogicException thrown by Quittio; catch QuittioException for every error of the library.
- [`QuittioException`](https://quittio.dev/docs/api/Quittio/Core/Exceptions/QuittioException) interfaceMarker interface for all exceptions thrown by Quittio.
- [`RuntimeException`](https://quittio.dev/docs/api/Quittio/Core/Exceptions/RuntimeException)\\RuntimeException thrown by Quittio; catch QuittioException for every error of the library.

### [Quittio\\Core\\Formats](https://quittio.dev/docs/api/Quittio/Core/Formats)

- [`DefaultFormatResolver`](https://quittio.dev/docs/api/Quittio/Core/Formats/DefaultFormatResolver)Format resolution in this order:
- [`ExtendedFeatures`](https://quittio.dev/docs/api/Quittio/Core/Formats/ExtendedFeatures)Detects data that only the profile EXTENDED can carry (sub lines, EXTENDED-only fields).
- [`FormatChoice`](https://quittio.dev/docs/api/Quittio/Core/Formats/FormatChoice)Result of the format resolution: output format key and profile key.
- [`FormatRegistry`](https://quittio.dev/docs/api/Quittio/Core/Formats/FormatRegistry)Known output formats. Country and network packages can register national formats.
- [`FormatResolver`](https://quittio.dev/docs/api/Quittio/Core/Formats/FormatResolver) interfaceChooses format and profile when none is given.
- [`FormatRule`](https://quittio.dev/docs/api/Quittio/Core/Formats/FormatRule) interfaceA rule of a country pack that decides the output format of an invoice.
- [`OutputFormat`](https://quittio.dev/docs/api/Quittio/Core/Formats/OutputFormat)Definition of an output format.

### [Quittio\\Core\\I18n](https://quittio.dev/docs/api/Quittio/Core/I18n)

- [`ArrayTranslator`](https://quittio.dev/docs/api/Quittio/Core/I18n/ArrayTranslator)Translator backed by PHP array files: {path}/{locale}/{group}.php.
- [`Translations`](https://quittio.dev/docs/api/Quittio/Core/I18n/Translations)Holds the translator used for code labels and validation messages.
- [`Translator`](https://quittio.dev/docs/api/Quittio/Core/I18n/Translator) interfaceMinimal translator contract so that the core works without Laravel. Keys use the form "group.key" (e.g. "labels.due\_date", "rules.BR-CO-25.message").

### [Quittio\\Core\\Mapping](https://quittio.dev/docs/api/Quittio/Core/Mapping)

- [`FieldDefinition`](https://quittio.dev/docs/api/Quittio/Core/Mapping/FieldDefinition)Metadata of one DTO field, read from its mapping attributes.
- [`FieldMatrix`](https://quittio.dev/docs/api/Quittio/Core/Mapping/FieldMatrix)Field metadata of all DTOs, derived from the mapping attributes (single source for profile validation, documentation and coverage reports).
- [`FieldReference`](https://quittio.dev/docs/api/Quittio/Core/Mapping/FieldReference)Generates docs/field-reference.md from the mapping attributes of the data model.

### [Quittio\\Core\\Mapping\\Attributes](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes)

- [`Binary`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Binary)Binary string; arrays and JSON carry it base64 encoded.
- [`Bt`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Bt)Business term or business group identifier from EN 16931 (e.g. BT-1, BG-25).
- [`Cardinality`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Cardinality)Cardinality according to EN 16931: 1, 0..1, 0..n or 1..n.
- [`Cii`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Cii)Location of the field in UN/CEFACT CII, relative to the parent element (informative).
- [`Computed`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Computed)The value is set by the calculator and is not a user input.
- [`ExtendedOnly`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/ExtendedOnly)The value exists only in the Factur-X/ZUGFeRD EXTENDED profile.
- [`InputFor`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/InputFor)Marks a user input that the calculator copies into the given business term.
- [`Internal`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Internal)Package-internal value without an EN 16931 business term (not written to XML).
- [`Level`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Level)Lowest Factur-X/ZUGFeRD profile level in which the field may be used. Fields without this attribute are available from level EN 16931 on.
- [`ListOf`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/ListOf)Element type of an array property, used for hydration and schema generation.
- [`MapOf`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/MapOf)Value type of an array property keyed by strings, e.g. line options keyed by line identifier; the hydrator keeps the keys.
- [`PdfOnly`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/PdfOnly)The value is used for the PDF only and never written to XML.
- [`RequiredIn`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/RequiredIn)Profile keys in which an optional EN 16931 field becomes mandatory (e.g. "xrechnung").
- [`Since`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Since)The field exists from the given version of EN 16931 on.
- [`TaxCurrency`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/TaxCurrency)Monetary value expressed in the VAT accounting currency (BT-6) instead of the invoice currency.
- [`Ubl`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Ubl)Location of the field in UBL 2.1, relative to the parent element (informative).
- [`Until`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/Until)The field exists up to and including the given version of EN 16931.
- [`XRechnungExtensionOnly`](https://quittio.dev/docs/api/Quittio/Core/Mapping/Attributes/XRechnungExtensionOnly)The value exists only in the XRechnung extension.

### [Quittio\\Core\\Pdf](https://quittio.dev/docs/api/Quittio/Core/Pdf)

- [`EmbeddedXml`](https://quittio.dev/docs/api/Quittio/Core/Pdf/EmbeddedXml)Invoice XML to be embedded into a PDF/A-3 (ZUGFeRD/Factur-X, XRechnung in PDF).
- [`LogoCache`](https://quittio.dev/docs/api/Quittio/Core/Pdf/LogoCache)Prepares logos for the PDF and caches the result.
- [`PdfEmbeddedFileExtractor`](https://quittio.dev/docs/api/Quittio/Core/Pdf/PdfEmbeddedFileExtractor)Extracts the embedded invoice XML from PDF files (ZUGFeRD 2.x, Factur-X, XRechnung in PDF).
- [`PdfException`](https://quittio.dev/docs/api/Quittio/Core/Pdf/PdfException)
- [`PdfRenderer`](https://quittio.dev/docs/api/Quittio/Core/Pdf/PdfRenderer) interfaceTurns HTML (from the template) into a PDF, embedding the invoice XML if requested.
- [`RemoteImageFetcher`](https://quittio.dev/docs/api/Quittio/Core/Pdf/RemoteImageFetcher)Downloads remote logos without server-side request forgery: only http and https, only hosts whose every resolved address (IPv4 and IPv6) is publicly routable, the connection pinned to the checked address (no second DNS lookup) and every redirect checked again.
- [`RenderRequest`](https://quittio.dev/docs/api/Quittio/Core/Pdf/RenderRequest)Input for a PDF renderer.

### [Quittio\\Core\\Pdf\\PostProcessing](https://quittio.dev/docs/api/Quittio/Core/Pdf/PostProcessing)

- [`MpdfPostProcessor`](https://quittio.dev/docs/api/Quittio/Core/Pdf/PostProcessing/MpdfPostProcessor)Imports the pages of an existing PDF (FPDI via mPDF), embeds the XML and writes PDF/A-3 metadata and output intent.
- [`PdfPostProcessor`](https://quittio.dev/docs/api/Quittio/Core/Pdf/PostProcessing/PdfPostProcessor) interfaceTurns an existing PDF into PDF/A-3 with embedded invoice XML (for callback and passthrough renderers).

### [Quittio\\Core\\Pdf\\Qr](https://quittio.dev/docs/api/Quittio/Core/Pdf/Qr)

- [`EpcGiroCodeGenerator`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Qr/EpcGiroCodeGenerator)EPC QR code ("GiroCode") for SEPA credit transfers, guideline EPC069-12 version 002.
- [`PaymentQrGenerator`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Qr/PaymentQrGenerator) interfaceCreates the payload of a payment QR code (GiroCode, Swiss QR bill, …).
- [`PaymentSlip`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Qr/PaymentSlip)The texts of a payment slip with receipt (ProvidesPaymentSlip), laid out by the templates after the Swiss QR bill: receipt (62 mm) and payment part (148 mm) in a strip of 210 × 105 mm at the bottom of the page, with the code at 46 × 46 mm.
- [`ProvidesPaymentSlip`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Qr/ProvidesPaymentSlip) interfaceA payment QR code generator whose code belongs on a payment slip of its own, e.g. the payment part and receipt of the Swiss QR bill. The default templates then print the slip at the bottom of a page of its own instead of the small code next to the bank details.
- [`QrImage`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Qr/QrImage)Renders QR codes as SVG data URIs for templates (no further dependency besides mpdf/qrcode).

### [Quittio\\Core\\Pdf\\Renderers](https://quittio.dev/docs/api/Quittio/Core/Pdf/Renderers)

- [`CallbackRenderer`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Renderers/CallbackRenderer)Own rendering function (e.g. Browsershot, Gotenberg) that returns PDF binary data. PDF/A and the embedded XML are added by the post processor.
- [`DenyingHttpClient`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Renderers/DenyingHttpClient)mPDF HTTP client that refuses every request (defence in depth).
- [`MpdfRenderer`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Renderers/MpdfRenderer)Default renderer: HTML/CSS to PDF/A-3b with mPDF, in pure PHP.
- [`PassthroughRenderer`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Renderers/PassthroughRenderer)Uses a finished PDF supplied by the application; only PDF/A and the XML are added.

### [Quittio\\Core\\Pdf\\Xmp](https://quittio.dev/docs/api/Quittio/Core/Pdf/Xmp)

- [`FacturXXmp`](https://quittio.dev/docs/api/Quittio/Core/Pdf/Xmp/FacturXXmp)XMP metadata for Factur-X/ZUGFeRD: the fx description and the PDF/A extension schema. Without the extension schema the PDF is readable, but not valid PDF/A.

### [Quittio\\Core\\Profiles](https://quittio.dev/docs/api/Quittio/Core/Profiles)

- [`AbstractProfile`](https://quittio.dev/docs/api/Quittio/Core/Profiles/AbstractProfile)Defaults shared by all profiles. Profiles override what differs.
- [`Basic`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Basic)Factur-X/ZUGFeRD BASIC: a subset of EN 16931 with lines.
- [`BasicWl`](https://quittio.dev/docs/api/Quittio/Core/Profiles/BasicWl)Factur-X/ZUGFeRD BASIC WL (without lines). Not an e-invoice in the sense of EN 16931.
- [`En16931`](https://quittio.dev/docs/api/Quittio/Core/Profiles/En16931)EN 16931 core invoice (Factur-X/ZUGFeRD profile EN 16931, also as plain CII or UBL).
- [`Extended`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Extended)Factur-X/ZUGFeRD EXTENDED: EN 16931 plus additional elements.
- [`Minimum`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Minimum)Factur-X/ZUGFeRD MINIMUM. Not an e-invoice in the sense of EN 16931; booking aid only.
- [`PeppolBis3`](https://quittio.dev/docs/api/Quittio/Core/Profiles/PeppolBis3)Peppol BIS Billing 3.0, a UBL based CIUS of EN 16931.
- [`Profile`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Profile) interfaceAn e-invoice profile (CIUS or extension): which fields are allowed or mandatory, which identifier goes into BT-24 and which additional rules apply.
- [`ProfileLevel`](https://quittio.dev/docs/api/Quittio/Core/Profiles/ProfileLevel) enumOrdered Factur-X/ZUGFeRD profile levels. Each level contains all fields of the lower levels.
- [`ProfileRegistry`](https://quittio.dev/docs/api/Quittio/Core/Profiles/ProfileRegistry)Known profiles by key. Country packs and network packages register further profiles.
- [`Syntax`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Syntax) enumXML syntax of an e-invoice.

### [Quittio\\Core\\Profiles\\Capabilities](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities)

- [`DescribesEmbeddedXml`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/DescribesEmbeddedXml) interfaceFor profiles whose XML is embedded in a PDF/A-3 with other XMP metadata than Factur-X ("Factur-X/ZUGFeRD Invoice", fx:Version "1.0"), e.g. XRechnung in ZUGFeRD.
- [`ExtendsCodeLists`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/ExtendsCodeLists) interfaceProfiles that accept additional codes on top of the EN 16931 code lists, e.g. the identifier schemes XR01 to XR03 of the XRechnung extension.
- [`ReplacesRules`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/ReplacesRules) interfaceProfiles that replace built-in rules with own rules under other codes, as the official validator configuration does, e.g. the XRechnung extension: BR-CO-16 by BR-DEX-09. The PHP rules driver does not run the replaced rules for this profile, so a violation is reported once.
- [`RequiresVatBreakdownRate`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/RequiresVatBreakdownRate) interfaceMarker for profiles that require the VAT category rate (BT-119) in every VAT breakdown, including category "O" (written as 0). Example: XRechnung (BR-DE-14).
- [`StructuredCashDiscountText`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/StructuredCashDiscountText) interfaceMarker for profiles that expect cash discounts as structured lines in BT-20, e.g. XRechnung: "#SKONTO#TAGE=14#PROZENT=2.00#".
- [`SupportsExtensionFields`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/SupportsExtensionFields) interfaceProfiles that transmit the fields of extensions of EN 16931, e.g. "xrechnung" for the fields marked with Mapping\\Attributes\\XRechnungExtensionOnly.
- [`SupportsSubLines`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/SupportsSubLines) interfaceProfiles that transmit sub lines (BG-DEX-01 of the XRechnung extension, the line hierarchy of EXTENDED). Invoices with sub lines are not upgraded to EXTENDED when they use such a profile.
- [`SupportsThirdPartyPayments`](https://quittio.dev/docs/api/Quittio/Core/Profiles/Capabilities/SupportsThirdPartyPayments) interfaceProfiles whose UBL invoices transmit third party payments (BG-DEX-09 of the XRechnung extension) without contradicting BR-CO-16.

### [Quittio\\Core\\Reading](https://quittio.dev/docs/api/Quittio/Core/Reading)

- [`DeclaredExemptionReasons`](https://quittio.dev/docs/api/Quittio/Core/Reading/DeclaredExemptionReasons)EN 16931 carries the VAT exemption reason (BT-120, BT-121) only on the VAT breakdown, the data model takes it from the lines (LineVat) and document allowances and charges. Readers copy the declared reasons back, so that a recalculation keeps them.
- [`DiagnosingXmlExtractor`](https://quittio.dev/docs/api/Quittio/Core/Reading/DiagnosingXmlExtractor) interfaceAn extractor that also reports where the XML came from and what it noticed on the way.
- [`EmbeddedXmlExtractor`](https://quittio.dev/docs/api/Quittio/Core/Reading/EmbeddedXmlExtractor) interfaceExtracts the embedded invoice XML from a hybrid PDF (ZUGFeRD/Factur-X, XRechnung in PDF).
- [`ExtractedXml`](https://quittio.dev/docs/api/Quittio/Core/Reading/ExtractedXml)The invoice XML found in a hybrid PDF, with the file specification it came from.
- [`FormatReader`](https://quittio.dev/docs/api/Quittio/Core/Reading/FormatReader) interfaceReads one XML invoice format into the data model.
- [`InvoiceReader`](https://quittio.dev/docs/api/Quittio/Core/Reading/InvoiceReader)Reads e-invoices from XML or PDF.
- [`ReadResult`](https://quittio.dev/docs/api/Quittio/Core/Reading/ReadResult)Result of reading an e-invoice: the parsed data, the totals declared in the document (kept unchanged for comparison), findings and the raw input.
- [`UnreadableInvoiceException`](https://quittio.dev/docs/api/Quittio/Core/Reading/UnreadableInvoiceException)The input is not a supported e-invoice.

### [Quittio\\Core\\Rendering](https://quittio.dev/docs/api/Quittio/Core/Rendering)

- [`PendingDocument`](https://quittio.dev/docs/api/Quittio/Core/Rendering/PendingDocument)Fluent render call for documents: Quittio::document($quote)->locale('de')->render().
- [`PendingInvoice`](https://quittio.dev/docs/api/Quittio/Core/Rendering/PendingInvoice)Fluent render call: Quittio::make($data)->profile()->format()->locale()->render().
- [`PreparedInvoice`](https://quittio.dev/docs/api/Quittio/Core/Rendering/PreparedInvoice)Calculated and validated invoice data plus the decisions a render run would take (format, profile, country pack, locale), without rendering anything. The XML of every format (also the one "pdf" embeds with b2cEmbedXml) is generated for the validation only. Used by the Managed layer to freeze an invoice before its documents are rendered; the validation always runs, whatever the validation mode.
- [`RenderedDocument`](https://quittio.dev/docs/api/Quittio/Core/Rendering/RenderedDocument)Rendered quote, delivery note, reminder or other document (PDF and HTML, never XML).
- [`RenderedInvoice`](https://quittio.dev/docs/api/Quittio/Core/Rendering/RenderedInvoice)Result of a render run. With several formats, every format is reachable via {@see self::as()}; all share the same calculation.
- [`RenderOptions`](https://quittio.dev/docs/api/Quittio/Core/Rendering/RenderOptions)Per call options of a render run; unset values fall back to the configuration.

### [Quittio\\Core\\Serialization](https://quittio.dev/docs/api/Quittio/Core/Serialization)

- [`ArrayHydrator`](https://quittio.dev/docs/api/Quittio/Core/Serialization/ArrayHydrator)Builds DTOs from plain arrays (the inverse of ArrayNormalizer).
- [`ArrayNormalizer`](https://quittio.dev/docs/api/Quittio/Core/Serialization/ArrayNormalizer)Converts DTOs into plain arrays (scalars only) for JSON, storage and APIs.
- [`JsonSchemaGenerator`](https://quittio.dev/docs/api/Quittio/Core/Serialization/JsonSchemaGenerator)Generates the JSON Schema (draft 2020-12) of InvoiceData::toArray() from the constructor signatures and mapping attributes, so that the schema never drifts from the model.
- [`JsonSchemaValidator`](https://quittio.dev/docs/api/Quittio/Core/Serialization/JsonSchemaValidator)Validates JSON input against the shipped invoice schema before hydration (requires the optional package opis/json-schema).

### [Quittio\\Core\\Serialization\\Snapshots](https://quittio.dev/docs/api/Quittio/Core/Serialization/Snapshots)

- [`SnapshotUpcaster`](https://quittio.dev/docs/api/Quittio/Core/Serialization/Snapshots/SnapshotUpcaster) interfaceMigrates a stored invoice snapshot from one version to the next one.
- [`SnapshotUpcasterChain`](https://quittio.dev/docs/api/Quittio/Core/Serialization/Snapshots/SnapshotUpcasterChain)Brings stored snapshots step by step to the current version (v1 → v2 → … → current).
- [`SnapshotVersionException`](https://quittio.dev/docs/api/Quittio/Core/Serialization/Snapshots/SnapshotVersionException)A snapshot cannot be brought to the current version: an upcaster is missing, or the snapshot was written by a newer version of the package.

### [Quittio\\Core\\Standards](https://quittio.dev/docs/api/Quittio/Core/Standards)

- [`StandardVersion`](https://quittio.dev/docs/api/Quittio/Core/Standards/StandardVersion) enumVersion of the semantic standard EN 16931-1.

### [Quittio\\Core\\Support](https://quittio.dev/docs/api/Quittio/Core/Support)

- [`Amount`](https://quittio.dev/docs/api/Quittio/Core/Support/Amount)Factory for monetary amounts.
- [`Date`](https://quittio.dev/docs/api/Quittio/Core/Support/Date)Calendar date without time of day.
- [`DatedValues`](https://quittio.dev/docs/api/Quittio/Core/Support/DatedValues)Values that change on dates, e.g. tax rates or reference interest rates: every value holds from its date until the next change.
- [`Decimal`](https://quittio.dev/docs/api/Quittio/Core/Support/Decimal)Helpers for exact decimal arithmetic. Floats are rejected on purpose, see rejectFloat().
- [`Macroable`](https://quittio.dev/docs/api/Quittio/Core/Support/Macroable) traitLightweight macro support without a dependency on Laravel. Country packs use it to add helpers such as smallAmount() to the invoice builder.
- [`Process`](https://quittio.dev/docs/api/Quittio/Core/Support/Process)Minimal external process runner with stdin, timeout and captured output.

### [Quittio\\Core\\Tax](https://quittio.dev/docs/api/Quittio/Core/Tax)

- [`CountryDefaultVat`](https://quittio.dev/docs/api/Quittio/Core/Tax/CountryDefaultVat)Default VAT of lines without VAT treatment, for InvoiceBuilder::useDefaultVat():
- [`CustomTaxPreset`](https://quittio.dev/docs/api/Quittio/Core/Tax/CustomTaxPreset)Ad-hoc tax preset, e.g. for an exemption with a specific legal reference.
- [`DatedTaxPreset`](https://quittio.dev/docs/api/Quittio/Core/Tax/DatedTaxPreset) interfaceA preset whose rate depends on the date of the supply, e.g. a standard rate that was lowered for half a year. The builder resolves it with the supply date of each line (SupplyDate); rate() returns the rate of today.
- [`StatesInvoiceNote`](https://quittio.dev/docs/api/Quittio/Core/Tax/StatesInvoiceNote) interfaceA preset that requires a note on the invoice, e.g. a statement the law prescribes for the special scheme of the preset. The builder adds the note once (BT-22, subject REG) when a line uses the preset, unless the invoice has a note with the same text already.
- [`SupplyDate`](https://quittio.dev/docs/api/Quittio/Core/Tax/SupplyDate)The date that decides the VAT rate of a line: the end of the line period (BT-135), its start (BT-134), the VAT point date (BT-7), the actual delivery date (BT-72), the end of the invoicing period (BT-74) and finally the issue date (BT-2), in this order.
- [`TaxPreset`](https://quittio.dev/docs/api/Quittio/Core/Tax/TaxPreset) interfaceA named VAT treatment provided by a country pack, e.g. "standard rate 19 %" or "small business exemption". Presets set category, rate, VATEX code and legal note text.
- [`TaxPresetCollection`](https://quittio.dev/docs/api/Quittio/Core/Tax/TaxPresetCollection)

### [Quittio\\Core\\Templates](https://quittio.dev/docs/api/Quittio/Core/Templates)

- [`PhpTemplateEngine`](https://quittio.dev/docs/api/Quittio/Core/Templates/PhpTemplateEngine)Plain PHP templates for use without Laravel.
- [`TemplateEngine`](https://quittio.dev/docs/api/Quittio/Core/Templates/TemplateEngine) interfaceTurns the view model into HTML for the PDF renderer (Blade, plain PHP, Twig …).

### [Quittio\\Core\\Testing](https://quittio.dev/docs/api/Quittio/Core/Testing)

- [`InvoiceFactory`](https://quittio.dev/docs/api/Quittio/Core/Testing/InvoiceFactory)Test data factory: InvoiceData::factory()->reverseCharge()->withLines(5)->make().
- [`Scenarios`](https://quittio.dev/docs/api/Quittio/Core/Testing/Scenarios)Example invoices for previews, tests and the official validation runs.

### [Quittio\\Core\\Validation](https://quittio.dev/docs/api/Quittio/Core/Validation)

- [`InvoiceValidator`](https://quittio.dev/docs/api/Quittio/Core/Validation/InvoiceValidator)Runs all configured validation drivers and merges their results.
- [`Messages`](https://quittio.dev/docs/api/Quittio/Core/Validation/Messages)Creates validation messages from the message catalog.
- [`Rule`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rule) interfaceA business or plausibility rule checked in PHP (levels L1 to L3 and L7).
- [`RuleOverrides`](https://quittio.dev/docs/api/Quittio/Core/Validation/RuleOverrides)Changes to the PHP rules by rule code: rules switched off, findings with another severity and rules replaced by own implementations. Codes match exactly or, with a trailing "\*", by prefix (e.g. "DE-USTG-\*"). The overrides apply to the PHP rules only; the findings of the XSD schema, KoSIT and veraPDF are never changed.
- [`Severity`](https://quittio.dev/docs/api/Quittio/Core/Validation/Severity) enum
- [`ValidationContext`](https://quittio.dev/docs/api/Quittio/Core/Validation/ValidationContext)Information available to rules while validating an invoice.
- [`ValidationDriver`](https://quittio.dev/docs/api/Quittio/Core/Validation/ValidationDriver) interfaceA validation driver checks one or more levels (PHP rules, XSD, KoSIT, veraPDF, …).
- [`ValidationException`](https://quittio.dev/docs/api/Quittio/Core/Validation/ValidationException)Thrown when an invoice does not pass validation. The full result is attached.
- [`ValidationLevel`](https://quittio.dev/docs/api/Quittio/Core/Validation/ValidationLevel) enumValidation levels.
- [`ValidationMessage`](https://quittio.dev/docs/api/Quittio/Core/Validation/ValidationMessage)A single validation finding.
- [`ValidationResult`](https://quittio.dev/docs/api/Quittio/Core/Validation/ValidationResult)Result of a validation run.
- [`ValidationSubject`](https://quittio.dev/docs/api/Quittio/Core/Validation/ValidationSubject)What is validated: the calculated data and, where available, the generated XML and PDF.

### [Quittio\\Core\\Validation\\Drivers](https://quittio.dev/docs/api/Quittio/Core/Validation/Drivers)

- [`KositArtifacts`](https://quittio.dev/docs/api/Quittio/Core/Validation/Drivers/KositArtifacts)Downloads the KoSIT validator and the XRechnung validator configuration (level L5) and compiles the Peppol BIS Billing 3.0 Schematron to XSLT with the Saxon bundled in the validator (requires Java).
- [`KositReportParser`](https://quittio.dev/docs/api/Quittio/Core/Validation/Drivers/KositReportParser)Converts a KoSIT validator report (VARL) into validation messages.
- [`KositValidator`](https://quittio.dev/docs/api/Quittio/Core/Validation/Drivers/KositValidator)Official Schematron validation (level L5) with the KoSIT validator.
- [`PhpRulesDriver`](https://quittio.dev/docs/api/Quittio/Core/Validation/Drivers/PhpRulesDriver)Built-in PHP rules: levels L1 (structure), L2 (profile), L3 (business rules) and L7 (plausibility).
- [`VeraPdfValidator`](https://quittio.dev/docs/api/Quittio/Core/Validation/Drivers/VeraPdfValidator)PDF/A conformance check (level L6) with veraPDF.
- [`XsdValidator`](https://quittio.dev/docs/api/Quittio/Core/Validation/Drivers/XsdValidator)XML schema validation (level L4) with the bundled CII D16B and UBL 2.1 schemas. XML of another syntax read by the reader of a country pack (e.g. ebInterface) is not checked here: the reader checks its structure.

### [Quittio\\Core\\Validation\\Plausibility](https://quittio.dev/docs/api/Quittio/Core/Validation/Plausibility)

- [`Iban`](https://quittio.dev/docs/api/Quittio/Core/Validation/Plausibility/Iban)IBAN check digit validation (ISO 13616, mod 97-10) without extensions.
- [`VatIdFormat`](https://quittio.dev/docs/api/Quittio/Core/Validation/Plausibility/VatIdFormat)Format of VAT identification numbers by country prefix (structure only, no check digits).
- [`VatIdVerification`](https://quittio.dev/docs/api/Quittio/Core/Validation/Plausibility/VatIdVerification)Result of an online VAT identifier check. $valid is null if no statement is possible: the service was not reachable or answered with an error, or it does not cover the identifier ($supported = false).
- [`VatIdVerifier`](https://quittio.dev/docs/api/Quittio/Core/Validation/Plausibility/VatIdVerifier) interfaceOnline check of VAT identifiers (e.g. EU VIES). Implementations must never throw because a service is unavailable; they return a result with $valid = null instead.
- [`ViesVerifier`](https://quittio.dev/docs/api/Quittio/Core/Validation/Plausibility/ViesVerifier)VAT identifier check via the REST interface of the EU VIES service.

### [Quittio\\Core\\Validation\\Rules](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules)

- [`CallbackRule`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/CallbackRule)A rule defined by a closure. The closure receives the invoice and a reporter.
- [`CodeListRules`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/CodeListRules)Code list rules of EN 16931 (BR-CL-…), based on the official code lists.
- [`En16931Rules`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/En16931Rules)EN 16931 business rules (BR-…) and conditions (BR-CO-…) checked on the data model.
- [`FieldMatrixRule`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/FieldMatrixRule)Mandatory and allowed fields of the selected profile (level L2), derived from the mapping attributes of the data model and the profile's additional requirements.
- [`Inspect`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/Inspect)Helpers shared by the rule sets.
- [`PeppolRules`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/PeppolRules)The Peppol BIS Billing 3.0 rules (PEPPOL-EN16931-…, PEPPOL-COMMON-…) that the data of an invoice can violate, with readable messages. Rules that the UBL writer always satisfies and rules covered by an identical EN 16931 rule are not repeated (docs/validation.md lists them). The complete rule set is checked with the official artifacts (level L5).
- [`PlausibilityRules`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/PlausibilityRules)Plausibility checks (level L7): IBAN check digits, BIC and VAT identifier formats, e-mail addresses, date logic and the VAT category against the destination country. The VIES check is added only if a verifier is given.
- [`QuittioRules`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/QuittioRules)Package rules (QUITTIO-…) that go beyond EN 16931.
- [`RuleReporter`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/RuleReporter)Collects the findings of one rule.
- [`StructureRules`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/StructureRules)Structure and data format checks of the data model (level L1).
- [`VatCategoryRules`](https://quittio.dev/docs/api/Quittio/Core/Validation/Rules/VatCategoryRules)VAT category rules of EN 16931 (BR-S, BR-Z, BR-E, BR-AE, BR-IC, BR-G, BR-O, BR-AF, BR-AG, BR-B).

### [Quittio\\Core\\View](https://quittio.dev/docs/api/Quittio/Core/View)

- [`AccessLog`](https://quittio.dev/docs/api/Quittio/Core/View/AccessLog)Records which view model fields a template read (for the mandatory field guard).
- [`AddressFormatter`](https://quittio.dev/docs/api/Quittio/Core/View/AddressFormatter) interfaceFormats postal addresses according to the conventions of a country.
- [`CountryNames`](https://quittio.dev/docs/api/Quittio/Core/View/CountryNames)Country names from ext-intl with the ISO code as fallback.
- [`FormattedValue`](https://quittio.dev/docs/api/Quittio/Core/View/FormattedValue)A value for templates: formatted for display and available in raw form. Casting to string returns the formatted value, so {{ $value }} prints it.
- [`Formatter`](https://quittio.dev/docs/api/Quittio/Core/View/Formatter) interfaceFormats values for display according to a locale.
- [`InternationalAddressFormatter`](https://quittio.dev/docs/api/Quittio/Core/View/InternationalAddressFormatter)Fallback address format: street lines, "postcode city", subdivision and, for foreign recipients, the country name in upper case as the last line.
- [`IntlFormatter`](https://quittio.dev/docs/api/Quittio/Core/View/IntlFormatter)Locale aware formatting with ext-intl and a fallback for German and English conventions.
- [`InvoiceTitle`](https://quittio.dev/docs/api/Quittio/Core/View/InvoiceTitle)Label key of the document title for a type code (BT-3).
- [`InvoiceViewModel`](https://quittio.dev/docs/api/Quittio/Core/View/InvoiceViewModel)The only object templates receive. Every value is available formatted ($value->formatted or {{ $value }}) and raw ($value->raw).
- [`LetterLayout`](https://quittio.dev/docs/api/Quittio/Core/View/LetterLayout)Position of the address field and marks on the first page, in millimetres from the top left corner (e.g. DIN 5008 form A/B in the German country pack).
- [`MandatoryFieldGuard`](https://quittio.dev/docs/api/Quittio/Core/View/MandatoryFieldGuard)Checks after rendering that the template printed all mandatory values.
- [`MandatoryFieldMissing`](https://quittio.dev/docs/api/Quittio/Core/View/MandatoryFieldMissing)A template omitted mandatory invoice information.
- [`Markdown`](https://quittio.dev/docs/api/Quittio/Core/View/Markdown)Safe Markdown subset for texts: paragraphs, lists, bold and italic. HTML in the input is shown as text, links keep only their text.
- [`ResolvedLogo`](https://quittio.dev/docs/api/Quittio/Core/View/ResolvedLogo)A logo of the presentation as the renderer gets it: a local file or a checked data URI (Pdf\\LogoCache), resolved before the view model is built, so that the view layer does no I/O.
- [`ViewContext`](https://quittio.dev/docs/api/Quittio/Core/View/ViewContext)Everything the view model factory needs besides the invoice data.
- [`ViewModelFactory`](https://quittio.dev/docs/api/Quittio/Core/View/ViewModelFactory)Builds the template view model from calculated invoice data.
- [`ViewNode`](https://quittio.dev/docs/api/Quittio/Core/View/ViewNode)Read-only node of the invoice view model with recorded property access.

### [Quittio\\Core\\View\\Model](https://quittio.dev/docs/api/Quittio/Core/View/Model)

- [`AccountView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/AccountView)A credit transfer account (BG-17).
- [`AddressView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/AddressView)A postal address.
- [`AllowanceChargeView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/AllowanceChargeView)An allowance or charge on document level (BG-20, BG-21).
- [`AttachmentView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/AttachmentView)An attached document (BG-24).
- [`AttributeView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/AttributeView)An item attribute (BG-32).
- [`CardView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/CardView)A payment card (BG-18).
- [`ContactView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/ContactView)Contact details of a party.
- [`DeliveryView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DeliveryView)Delivery information (BG-13).
- [`DescribedAmountView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DescribedAmountView)An amount with its description: a third party payment or a reminder fee.
- [`DescriptionView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DescriptionView)The item description of a line.
- [`DesignView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DesignView)The design values: colours, font, logo, letter layout, sender line and footer.
- [`DirectDebitView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DirectDebitView)A direct debit (BG-19).
- [`DiscountView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DiscountView)A cash discount of the payment terms.
- [`DocumentInfoView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DocumentInfoView)Information of documents (quotes, delivery notes, reminders, statements …).
- [`DocumentView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DocumentView)The "document" node: type and kind of the invoice or document.
- [`DunningView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/DunningView)A payment reminder.
- [`InterestView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/InterestView)An interest charge of a reminder.
- [`LineAllowanceChargeView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/LineAllowanceChargeView)An allowance or charge of a line (BG-27, BG-28).
- [`LineGroupView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/LineGroupView)A group of lines for display.
- [`LineOptionsView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/LineOptionsView)The options of a document line.
- [`LineView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/LineView)An invoice line (BG-25), also a sub line.
- [`MetaView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/MetaView)Locale, custom values and source of the invoice.
- [`NoteView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/NoteView)A note (BG-1) other than the legal notes.
- [`OpenItemView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/OpenItemView)An open invoice of a reminder or statement.
- [`PackageView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PackageView)A package of a delivery note.
- [`PartyView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PartyView)A party: "seller" and "buyer", and "issuer" and "recipient", which stand for one of them.
- [`PayeeView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PayeeView)The payee (BG-10).
- [`PaymentSlipSectionView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PaymentSlipSectionView)One heading of a payment slip with its lines; without lines an empty field to fill in by hand.
- [`PaymentSlipView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PaymentSlipView)The payment slip of a payment QR code, e.g. the payment part and receipt of the Swiss QR bill.
- [`PaymentTermsView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PaymentTermsView)The payment terms (BT-20) with due date and cash discounts.
- [`PaymentView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PaymentView)The payment instructions (BG-16).
- [`PrecedingInvoiceView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/PrecedingInvoiceView)A preceding invoice reference (BG-3).
- [`QrCodeView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/QrCodeView)The payment QR code.
- [`ReferenceView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/ReferenceView)A filled document reference, e.g. the purchase order.
- [`StatementView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/StatementView)An account statement.
- [`TaxRepresentativeView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/TaxRepresentativeView)The seller tax representative (BG-11).
- [`TextsView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/TextsView)The texts of the presentation.
- [`TotalsView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/TotalsView)The document totals (BG-22).
- [`UnitView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/UnitView)The unit of measure of a line.
- [`VatRowView`](https://quittio.dev/docs/api/Quittio/Core/View/Model/VatRowView)A row of the VAT breakdown (BG-23).
- [`ViewList`](https://quittio.dev/docs/api/Quittio/Core/View/Model/ViewList)A list (or a map, such as "labels") of the view model whose entries have one type, e.g. ViewList\<LineView> for "lines" or ViewList\<string> for "legalNotes".

### [Quittio\\Core\\Xml](https://quittio.dev/docs/api/Quittio/Core/Xml)

- [`Format`](https://quittio.dev/docs/api/Quittio/Core/Xml/Format)Number formats for XML: dot as decimal separator, no grouping, no exponent.
- [`PaymentTermsText`](https://quittio.dev/docs/api/Quittio/Core/Xml/PaymentTermsText)Builds the payment terms text (BT-20) from structured payment terms.
- [`SerializationOptions`](https://quittio.dev/docs/api/Quittio/Core/Xml/SerializationOptions)Options for XML serialisation.
- [`UnsafeXmlException`](https://quittio.dev/docs/api/Quittio/Core/Xml/UnsafeXmlException)Rejected XML input (DOCTYPE, too large, not well-formed).
- [`XmlSecurity`](https://quittio.dev/docs/api/Quittio/Core/Xml/XmlSecurity)Safe XML loading for untrusted input.
- [`XmlSerializer`](https://quittio.dev/docs/api/Quittio/Core/Xml/XmlSerializer) interfaceWrites calculated invoice data as XML in one syntax.

### [Quittio\\Core\\Xml\\Cii](https://quittio.dev/docs/api/Quittio/Core/Xml/Cii)

- [`CiiReader`](https://quittio.dev/docs/api/Quittio/Core/Xml/Cii/CiiReader)Reads UN/CEFACT Cross Industry Invoices (Factur-X/ZUGFeRD, XRechnung CII) into the data model.
- [`CiiWriter`](https://quittio.dev/docs/api/Quittio/Core/Xml/Cii/CiiWriter)Writes UN/CEFACT Cross Industry Invoice (D16B) according to the EN 16931 binding (CEN/TS 16931-3-3) and the Factur-X/ZUGFeRD profiles.

### [Quittio\\Core\\Xml\\Ubl](https://quittio.dev/docs/api/Quittio/Core/Xml/Ubl)

- [`UblReader`](https://quittio.dev/docs/api/Quittio/Core/Xml/Ubl/UblReader)Reads UBL 2.1 Invoice and CreditNote documents (EN 16931, XRechnung UBL, Peppol BIS) into the data model.
- [`UblWriter`](https://quittio.dev/docs/api/Quittio/Core/Xml/Ubl/UblWriter)Writes OASIS UBL 2.1 Invoice and CreditNote documents according to the EN 16931 binding (CEN/TS 16931-3-2). Credit note type codes produce a CreditNote document.

```json
{"@context":"https://schema.org","@graph":[{"@id":"https://quittio.dev/#website","@type":"WebSite","description":"E-Rechnungen für PHP und Laravel: ZUGFeRD, XRechnung und Peppol erstellen, prüfen, lesen und archivieren.","inLanguage":"de-DE","name":"Quittio","url":"https://quittio.dev/","publisher":{"@id":"https://quittio.dev/#identity"},"workTranslation":{"@id":"https://quittio.dev/en#website"}},{"@id":"https://quittio.dev/docs/api/Quittio/Core#webpage","@type":"WebPage","description":"The public classes in Quittio\\Core.","name":"Quittio\\Core – API-Referenz","url":"https://quittio.dev/docs/api/Quittio/Core","isPartOf":{"@id":"https://quittio.dev/#website"},"potentialAction":[{"@type":"ReadAction","target":["https://quittio.dev/docs/api/Quittio/Core"]}],"primaryImageOfPage":{"@id":"https://quittio.dev/#logo"}},{"@id":"https://quittio.dev/#identity","@type":"Organization","description":"Open-Source-Bibliothek für E-Rechnungen in PHP und Laravel (ZUGFeRD, XRechnung, Peppol) und Quittio Managed.","email":"kontakt@niklasforst.de","legalName":"Niklas Forst – Softwareentwicklung","name":"Quittio","url":"https://quittio.dev","founder":{"@type":"Person","name":"Niklas Forst","url":"https://quittio.dev/ueber"},"logo":{"@id":"https://quittio.dev/#logo"},"sameAs":["https://github.com/Quittio/quittio","https://packagist.org/packages/quittio/quittio"]},{"@id":"https://quittio.dev/#logo","@type":"ImageObject","caption":"Quittio","contentUrl":"https://quittio.dev/logo.png","inLanguage":"de-DE","url":"https://quittio.dev/logo.png"}]}
```