update readme

README.md

@@ -28,19 +28,20 @@ let transfer_action = Action::Transfer(TransferAction { deposit: U128(1) });
 let actions = vec![transfer_action];
 
 let near_tx = TransactionBuilder::new::<NEAR>()
-        .signer_id(signer_id.to_string())
-        .signer_public_key(signer_public_key.to_public_key().unwrap())
-        .nonce(nonce)
-        .receiver_id(receiver_id.to_string())
-        .block_hash(block_hash_str.to_block_hash().unwrap())
-        .actions(actions)
-        .build();
+    .signer_id(signer_id.to_string())
+    .signer_public_key(signer_public_key.to_public_key().unwrap())
+    .nonce(nonce)
+    .receiver_id(receiver_id.to_string())
+    .block_hash(block_hash_str.to_block_hash().unwrap())
+    .actions(actions)
+    .build();
 
 // Now you have access to build_for_signing that returns the encoded payload
 let near_tx_encoded = near_tx.build_for_signing();
 ```
 
-Building Ethereum transaction:
+Building an Ethereum transaction:
+
 ```rust
 let to_address_str = "d8dA6BF26964aF9D7eEd9e03E53415D37aA96045";
 let to_address = parse_eth_address(to_address_str);
@@ -53,16 +54,59 @@ let data: Vec<u8> = vec![];
 let value: u128 = 10000000000000000; // 0.01 ETH
 
 let evm_tx = TransactionBuilder::new::<EVM>()
-        .nonce(nonce)
-        .to(to_address)
-        .value(value)
-        .input(data.clone())
-        .max_priority_fee_per_gas(max_priority_fee_per_gas)
-        .max_fee_per_gas(max_gas_fee)
-        .gas_limit(gas_limit)
-        .chain_id(chain_id)
-        .build();
+    .nonce(nonce)
+    .to(to_address)
+    .value(value)
+    .input(data.clone())
+    .max_priority_fee_per_gas(max_priority_fee_per_gas)
+    .max_fee_per_gas(max_gas_fee)
+    .gas_limit(gas_limit)
+    .chain_id(chain_id)
+    .build();
 
 // Now you have access to build_for_signing that returns the encoded payload
 let rlp_encoded = evm_tx.build_for_signing();
 ```
+
+Building a Bitcoin transaction:
+
+```rust
+let txid_str = "2ece6cd71fee90ff613cee8f30a52c3ecc58685acf9b817b9c467b7ff199871c";
+let hash = Hash::from_hex(txid_str).unwrap();
+let txid = Txid(hash);
+let vout = 0;
+
+let txin: TxIn = TxIn {
+    previous_output: OutPoint::new(txid, vout as u32),
+    script_sig: ScriptBuf::default(), // For a p2pkh script_sig is initially empty.
+    sequence: Sequence::MAX,
+    witness: Witness::default(),
+};
+
+let sender_script_pubkey_hex = "76a914cb8a3018cf279311b148cb8d13728bd8cbe95bda88ac";
+let sender_script_pubkey = ScriptBuf(sender_script_pubkey_hex.as_bytes().to_vec());
+
+let receiver_script_pubkey_hex = "76a914406cf8a18b97a230d15ed82f0d251560a05bda0688ac";
+let receiver_script_pubkey = ScriptBuf(receiver_script_pubkey_hex.as_bytes().to_vec());
+
+// The spend output is locked to a key controlled by the receiver.
+let spend_txout: TxOut = TxOut {
+    value: Amount::from_sat(500_000_000),
+    script_pubkey: receiver_script_pubkey,
+};
+
+let change_txout = TxOut {
+    value: Amount::from_sat(100_000_000),
+    script_pubkey: sender_script_pubkey,
+};
+
+let bitcoin_tx = TransactionBuilder::new::<BITCOIN>()
+    .version(Version::One)
+    .inputs(vec![txin])
+    .outputs(vec![spend_txout, change_txout])
+    .lock_time(LockTime::from_height(0).unwrap())
+    .build();
+
+// Prepare the transaction for signing
+let encoded_tx = bitcoin_tx.build_for_signing_legacy(EcdsaSighashType::All);
+```