{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "#/components/schemas/Invoice",
  "title": "Invoice",
  "type": "object",
  "properties": {
    "id": {
      "type": "integer"
    },
    "state": {
      "type": "string",
      "enum": [
        "open",
        "pending",
        "unpaid",
        "paid",
        "failed",
        "cancelled"
      ]
    },
    "friendly_id": {
      "type": "string",
      "description": "Human-readable invoice ID (e.g., 2026-00000001)"
    },
    "month": {
      "type": "string",
      "description": "Billing month in YYYY-MM format"
    },
    "due_on": {
      "type": "string",
      "format": "date"
    },
    "created_at": {
      "type": "string",
      "format": "date-time"
    },
    "updated_at": {
      "type": "string",
      "format": "date-time"
    },
    "cost": {
      "type": "number",
      "format": "float",
      "description": "Invoice total amount"
    },
    "currency": {
      "type": "string",
      "description": "ISO 4217 currency code"
    },
    "account": {
      "type": "object",
      "properties": {
        "id": {
          "type": "integer"
        },
        "org_name": {
          "type": "string"
        }
      }
    },
    "line_items": {
      "type": "array",
      "items": {
        "$ref": "#/components/schemas/InvoiceLineItem"
      }
    }
  }
}