Bitcoin Integration

Tomo Extension Wallet injects tomo_btc into the window object in your browser. dApp can easily interact with the wallet via window.tomo_btc. The following demo code shows how it works:

const example = async () => {
    // connect to tomo wallet and get accounts
    const accounts = await window.tomo_btc.requestAccounts()
    
    // the first account is the selected account
    const account = accounts[0]
        
    const signature = await window.tomo_btc.signMessage('Hello Tomo', 'bip322-simple')
    // do something about the signature
}

Tomo extension wallet follows the wallet adaptor interface defined by Babylon chain. Any Bitcoin ecosystem dApps can use the following Tomo implementation.

import { WalletProvider, Network, Fees, UTXO, WalletInfo } from "./wallet_provider";
import {
  getAddressBalance,
  getTipHeight,
  getFundingUTXOs,
  getNetworkFees,
  pushTx
} from "../mempool_api";

export class TOMOWallet extends WalletProvider {
  private tomoWalletInfo: WalletInfo | undefined;

  constructor() {
    super();
  }

  connectWallet = async (): Promise<this> => {
    const workingVersion = "1.1.1";
    if (!window.tomo_btc) {
      throw new Error("Tomo extension wallet not found");
    }

    const tomowallet = window.tomo_btc;
    let result = null;
    try {
      result = await tomowallet?.requestAccounts();
    } catch (error) {
      throw new Error("Bitcoin is not enabled in Tomo wallet");
    }

    let compressedPublicKey = null;
    try {
      compressedPublicKey = await tomowallet?.getPublicKey();
    } catch (error) {
      throw new Error("Bitcoin is not enabled in Tomo wallet");
    }

    if (compressedPublicKey && result[0]) {
      this.tomoWalletInfo = {
        publicKeyHex: compressedPublicKey,
        address: result[0],
      };
      return this;
    } else {
      throw new Error("Failed to connect to Tomo wallet");
    }
  };

  getWalletProviderName = async (): Promise<string> => {
    return "Tomo";
  };

  getAddress = async (): Promise<string> => {
    if (!this.tomoWalletInfo) {
      throw new Error("Tomo wallet not connected");
    }
    return this.tomoWalletInfo.address;
  };

  getPublicKeyHex = async (): Promise<string> => {
    if (!this.tomoWalletInfo) {
      throw new Error("Tomo wallet not connected");
    }
    return this.tomoWalletInfo.publicKeyHex;
  };

  signPsbt = async (psbtHex: string): Promise<string> => {
    if (!this.tomoWalletInfo) {
      throw new Error("Tomo wallet not connected");
    }
    return await window?.tomo_btc?.signPsbt(psbtHex);
  };

  signPsbts = async (psbtsHexes: string[]): Promise<string[]> => {
    if (!this.tomoWalletInfo) {
      throw new Error("Tomo wallet not connected");
    }
    return await window?.tomo_btc?.signPsbts(psbtsHexes);
  };

  signMessageBIP322 = async (message: string): Promise<string> => {
    if (!this.tomoWalletInfo) {
      throw new Error("TOMO Wallet not connected");
    }
    return await window?.tomo_btc?.signMessage(
      message,
      "bip322-simple",
    );
  };

  getNetwork = async (): Promise<Network> => {
    return "testnet";
  };

  on = (eventName: string, callBack: () => void) => {
    if (!this.tomoWalletInfo) {
      throw new Error("TOMO Wallet not connected");
    }
    if (eventName === "accountChanged") {
      return window.tomo_btc.on(eventName, callBack);
    }
  };

  getBalance = async (): Promise<number> => {
    return await getAddressBalance(await this.getAddress());
  };

  getNetworkFees = async (): Promise<Fees> => {
    return await getNetworkFees();
  };

  pushTx = async (txHex: string): Promise<string> => {
    return await pushTx(txHex);
  };

  getUtxos = async (address: string, amount: number): Promise<UTXO[]> => {
    return await getFundingUTXOs(address, amount);
  };

  getBTCTipHeight = async (): Promise<number> => {
    return await getTipHeight();
  };
}

Address Type

Tomo extension wallet supports the following Bitcoin wallet type:

• Legacy (P2PKH)

• Nested SegWit (P2SH)

• Native SegWit (P2WPKH)

• Taproot (P2TR)

Message Signing

Tomo extension wallet support the ECDSA signature of the above four wallet types.

PSBT Signing

Tomo extension wallet supports the PSBT signing of the following wallet types:

• Nested SegWit (P2SH)

• Native SegWit (P2WPKH)

• Taproot (P2TR)