Invoice types

The types the invoice domain defines, with the fields other domains add to them.

Objects

`Invoice`

An amount a company owes, issued as a document and settled separately from the orders it bills. One invoice may cover several orders, and an order paid on account is billed by one later.

Field	Type	Description
`id`	`ID!`	Unique identifier of the invoice
`invoiceNumber`	`String!`	Invoice number as the issuing system assigned it
`invoiceDate`	`Date!`	Calendar date the invoice was issued
`dueDate`	`Date`	Calendar date payment is due. Null where the issuer set no term.
`status`	`InvoiceStatusType!`	Where the invoice stands, derived from what has been collected
`total`	`Money!`	What the invoice bills in total
`amountPaid`	`Money!`	What has been collected against it
`amountDue`	`Money!`	What is still to be collected
`reference`	`String`	The issuer's own reference, usually the buyer's, shown on the document
`invoiceUrl`	`URL`	Link to the invoice document, where the issuer publishes one
`orderNumbers`	`[String!]!`	Numbers of the orders this invoice bills
`payable`	`Boolean!`	Whether a payment may be started against this invoice right now. False once nothing is outstanding, and false while a payment is already underway. A client cannot derive the second: an invoice with a pending charge still shows a balance, and offering to pay it again is how the same amount gets collected twice.
`availablePaymentMethods`	`[PaymentMethod!]!`	How this invoice may be paid. Not the same list a cart gets: paying on account is left out, because the invoice exists in the first place because credit was granted, and settling it on account would grant the same credit again.Arguments: `device`

`InvoiceResult`

Paginated result containing invoices

Field	Type	Description
`items`	`[Invoice!]!`	Invoices in the current page
`pagination`	`Pagination!`	Where this page sits within the full result set
`statusCounts`	`[InvoiceStatusCount!]`	How many invoices each status holds under this list's search term and date range, whatever its status filter, so every status tab can show a count. Asked of the engine once per status, so query it where the tabs are shown. Null when the engine cannot count per status.

`InvoiceStatusCount`

The number of invoices in one status

Field	Type	Description
`status`	`InvoiceStatusType!`
`count`	`Int!`

Enums

`InvoiceStatusType`

Where an invoice stands, derived on read from what has been collected against it. Nothing stores this: a status field and a ledger of transactions can disagree, and only one of them is what the money did.

`OPEN`	Nothing collected, and the due date has not passed
`OVERDUE`	Nothing collected, and the due date has passed
`PAYMENT_UNDERWAY`	A payment has been started against it and has not finished
`PARTLY_PAID`	Some of it has been collected and a balance remains
`PAID`	Collected in full
`CREDITED`	Credited back, in whole or in part