Safety & Fund Recovery

┌─────────────┐     ┌──────────┐     ┌───────────────────┐     ┌──────────┐     ┌───────────┐
│  INITIATED  │ ──▶ │ BRIDGING │ ──▶ │ BRIDGE_CONFIRMED  │ ──▶ │ SWAPPING │ ──▶ │ COMPLETED │
└─────────────┘     └──────────┘     └───────────────────┘     └──────────┘     └───────────┘
                                              │                      │                 ✅
                                              │                      │
                                              │                      └── 3 retries failed ──▶ ┌────────────────┐
                                              │                                               │ FALLBACK_SENT  │
                                              │                                               │ (USDCh to user)│
                                              │                                               └────────────────┘
                                              │                                                       ⚠️
                                              └── unrecoverable (rare) ───▶ ┌────────┐
                                                                            │ FAILED │
                                                                            └────────┘
                                                                               ❌

INITIATED → BRIDGING → BRIDGE_CONFIRMED → SWAPPING → COMPLETED

// 1. Ask the user for their Step 1 tx hash (they have it in their wallet history)
const txHash = "0x…"; // from user input

// 2. Build the EIP-712 message using the canonical domain
const eip712 = {
  domain: {
    name: "HypermidInboundReceiver",
    version: "1",
    chainId: 8453, // source chain of Step 1
  },
  types: {
    RegisterDeposit: [
      { name: "txHash",            type: "bytes32" },
      { name: "toAddress",         type: "address" },
      { name: "outputToken",       type: "address" },
      { name: "destinationDomain", type: "uint32"  },
    ],
  },
  primaryType: "RegisterDeposit",
  message: {
    txHash,
    toAddress: userAddress,
    outputToken: "0xA1077a294dDE1B09bB078844df40758a5D0f9a27", // e.g. WPLS
    destinationDomain: 369,
  },
};

// 3. Have the user sign (gasless)
const signature = await wallet.signTypedData(eip712);

// 4. POST to the API
await fetch("https://api.hypermid.io/v1/inbound-receiver/register", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    txHash,
    fromAddress: userAddress,
    toAddress: userAddress,
    outputToken: eip712.message.outputToken,
    destinationDomain: 369,
    signature,
  }),
});