{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/ordway/main/json-schema/invoice.json",
  "title": "Invoice",
  "description": "An Ordway billing invoice",
  "type": "object",
  "required": ["company_id", "invoice_id", "invoice_line_no"],
  "properties": {
    "company_id": {
      "type": "string",
      "description": "Identifier for the Ordway company account"
    },
    "invoice_id": {
      "type": "string",
      "description": "Unique identifier for the invoice"
    },
    "invoice_line_no": {
      "type": "string",
      "description": "Line number within the invoice"
    },
    "customer_id": {
      "type": "string",
      "description": "ID of the billed customer"
    },
    "customer_name": {
      "type": ["string", "null"],
      "description": "Name of the billed customer"
    },
    "invoice_date": {
      "type": ["string", "null"],
      "format": "date",
      "description": "Date the invoice was issued"
    },
    "due_date": {
      "type": ["string", "null"],
      "format": "date",
      "description": "Date payment is due"
    },
    "billing_run_id": {
      "type": ["string", "null"],
      "description": "ID of the billing run that generated this invoice"
    },
    "subtotal": {
      "type": ["number", "null"],
      "description": "Invoice subtotal before tax"
    },
    "invoice_tax": {
      "type": ["number", "null"],
      "description": "Total tax amount"
    },
    "invoice_amount": {
      "type": ["number", "null"],
      "description": "Total invoice amount including tax"
    },
    "paid_amount": {
      "type": ["number", "null"],
      "description": "Amount paid against this invoice"
    },
    "balance": {
      "type": ["number", "null"],
      "description": "Remaining balance due"
    },
    "status": {
      "type": ["string", "null"],
      "enum": ["draft", "open", "paid", "void", "posted", null],
      "description": "Invoice status"
    },
    "notes": {
      "type": ["string", "null"],
      "description": "Notes or comments on the invoice"
    },
    "currency": {
      "type": ["string", "null"],
      "description": "Invoice currency (ISO 4217)"
    },
    "payment_terms": {
      "type": ["string", "null"],
      "description": "Payment terms for this invoice"
    },
    "subscription_id": {
      "type": ["string", "null"],
      "description": "ID of the source subscription"
    },
    "product_id": {
      "type": ["string", "null"],
      "description": "ID of the billed product"
    },
    "product_name": {
      "type": ["string", "null"],
      "description": "Name of the billed product"
    },
    "charge_id": {
      "type": ["string", "null"],
      "description": "ID of the charge"
    },
    "charge_name": {
      "type": ["string", "null"],
      "description": "Name of the charge"
    },
    "charge_type": {
      "type": ["string", "null"],
      "description": "Type of charge (recurring, one_time, usage)"
    },
    "description": {
      "type": ["string", "null"],
      "description": "Line item description"
    },
    "start_date": {
      "type": ["string", "null"],
      "format": "date",
      "description": "Service period start date"
    },
    "end_date": {
      "type": ["string", "null"],
      "format": "date",
      "description": "Service period end date"
    },
    "quantity": {
      "type": ["number", "null"],
      "description": "Quantity billed"
    },
    "discount": {
      "type": ["number", "null"],
      "description": "Discount percentage applied"
    },
    "effective_price": {
      "type": ["number", "null"],
      "description": "Effective price after discounts"
    },
    "invoice_pdf_url": {
      "type": ["string", "null"],
      "format": "uri",
      "description": "URL to download the invoice PDF"
    },
    "emailed": {
      "type": ["boolean", "null"],
      "description": "Whether the invoice has been emailed to the customer"
    },
    "exchange_rate": {
      "type": ["number", "null"],
      "description": "Currency exchange rate applied"
    },
    "custom_fields": {
      "type": ["object", "null"],
      "additionalProperties": true,
      "description": "User-defined custom fields"
    },
    "created_by": {
      "type": ["string", "null"],
      "description": "User who created the record"
    },
    "updated_by": {
      "type": ["string", "null"],
      "description": "User who last updated the record"
    },
    "created_date": {
      "type": ["string", "null"],
      "format": "date-time",
      "description": "Timestamp when the record was created"
    },
    "updated_date": {
      "type": ["string", "null"],
      "format": "date-time",
      "description": "Timestamp when the record was last updated"
    }
  }
}