Invoice Token

interface InvoiceMetadata {
  invoiceNumber:       string;
  debtorReference:     string;
  faceValueUSD:        bigint;   // 18 decimals
  discountRateBps:     bigint;   // e.g. 200 = 2% discount
  issuanceDate:        bigint;   // Unix timestamp
  dueDate:             bigint;   // Unix timestamp
  invoiceDocumentHash: string;   // bytes32 — IPFS hash
  currency:            string;   // ISO 4217: NGN | GHS | KES | USD
  lastUpdated:         bigint;
}

PENDING (0)   ← Invoice issued, not yet funded
FUNDED  (1)   ← Invoice has been funded by investor(s)
REPAID  (2)   ← Debtor has repaid
DEFAULTED (3) ← Debtor has defaulted

const now     = BigInt(Math.floor(Date.now() / 1000));
const ninetyDays = BigInt(90 * 24 * 60 * 60);

const result = await factory.deployInvoice({
  name:        "Dangote Supply Invoice Q1",
  symbol:      "DSI",
  assetId:     "INV-2025-0042",
  countryCode: "NG",
  metadata: {
    invoiceNumber:       "INV-2025-0042",
    debtorReference:     "DANGOTE-CEMENT",
    faceValueUSD:        ethers.parseEther("250000"),
    discountRateBps:     BigInt(180),    // 1.8% discount
    issuanceDate:        now,
    dueDate:             now + ninetyDays,
    invoiceDocumentHash: ethers.ZeroHash,
    currency:            "NGN",
    lastUpdated:         now,
  },
});

Transfer(address indexed from, address indexed to, uint256 value)
MetadataUpdated(uint256 indexed version, uint256 timestamp)
InvoiceStatusChanged(uint8 indexed oldStatus, uint8 indexed newStatus, uint256 timestamp)