IBC Cross-Chain Transfers

import { useMemo } from 'react';
import { View, Text, Button } from 'react-native';
import { useParaCosmjsProtoSigner, useParaCosmjsSignAndBroadcast } from '@getpara/react-native-wallet/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 <Text>Loading...</Text>;

  return (
    <View>
      <Text>From: {address}</Text>
      <Button
        title={isPending ? 'Transferring...' : 'Send 1 ATOM to Osmosis'}
        onPress={sendIBCTransfer}
        disabled={isPending}
      />
    </View>
  );
}