IBC Cross-Chain Transfers

import { useMemo } from "react";
import { useParaCosmjsProtoSigner, useParaCosmjsSignAndBroadcast } from "@getpara/react-sdk/cosmos";
import { SigningStargateClient, coins } from "@cosmjs/stargate";
import { MsgTransfer } from "cosmjs-types/ibc/applications/transfer/v1/tx";
import { Height } from "cosmjs-types/ibc/core/client/v1/client";

const RPC_URL = "https://rpc.cosmos.directory/cosmoshub";

function IBCTransfer() {
  const { protoSigner, isLoading } = useParaCosmjsProtoSigner();

  const address = protoSigner?.address;

  const client = useMemo(
    () => protoSigner ? SigningStargateClient.connectWithSigner(RPC_URL, protoSigner) : undefined,
    [protoSigner]
  );

  const { signAndBroadcastAsync, isPending } = useParaCosmjsSignAndBroadcast(protoSigner, client);

  const sendIBCTransfer = async () => {
    if (!protoSigner || !address || !client) return;

    const resolvedClient = await client;
    const currentHeight = await resolvedClient.getHeight();

    const timeoutHeight = Height.fromPartial({
      revisionNumber: 1n,
      revisionHeight: BigInt(currentHeight + 1000),
    });

    const msgTransfer = {
      typeUrl: "/ibc.applications.transfer.v1.MsgTransfer",
      value: MsgTransfer.fromPartial({
        sourcePort: "transfer",
        sourceChannel: "channel-141",
        token: {
          denom: "uatom",
          amount: "1000000",
        },
        sender: address,
        receiver: "osmo1...",
        timeoutHeight: timeoutHeight,
        timeoutTimestamp: 0n,
      }),
    };

    const fee = {
      amount: coins(5000, "uatom"),
      gas: "250000",
    };

    try {
      const result = await signAndBroadcastAsync({
        messages: [msgTransfer],
        fee,
        memo: "IBC transfer via Para",
      });

      console.log("IBC transfer initiated:", result.transactionHash);
    } catch (error) {
      console.error("IBC transfer failed:", error);
    }
  };

  if (isLoading) return <div>Loading...</div>;

  return (
    <div>
      <p>From: {address}</p>
      <button onClick={sendIBCTransfer} disabled={isPending}>
        {isPending ? "Transferring..." : "Send 1 ATOM to Osmosis"}
      </button>
    </div>
  );
}