Merge pull request #210 from BitGo/BTC-2976.hydrate-from-legacy

feat(wasm-utxo)!: add legacy transaction to PSBT conversion

Author: OttoAllmendinger

packages/wasm-utxo/js/fixedScriptWallet/BitGoPsbt.ts

@@ -126,6 +126,12 @@ export type ParseOutputsOptions = {
   payGoPubkeys?: ECPairArg[];
 };
 
+export type HydrationUnspent = {
+  chain: number;
+  index: number;
+  value: bigint;
+};
+
 export class BitGoPsbt implements IPsbtWithAddress {
   protected constructor(protected _wasm: WasmBitGoPsbt) {}
 
@@ -185,6 +191,34 @@ export class BitGoPsbt implements IPsbtWithAddress {
     return new BitGoPsbt(wasm);
   }
 
+  /**
+   * Convert a half-signed legacy transaction to a psbt-lite.
+   *
+   * Extracts partial signatures from scriptSig/witness and creates a PSBT
+   * with proper wallet metadata (bip32Derivation, scripts, witnessUtxo).
+   * Only supports p2sh, p2shP2wsh, and p2wsh inputs (not taproot).
+   *
+   * @param txBytes - The serialized half-signed legacy transaction
+   * @param network - Network name
+   * @param walletKeys - The wallet's root keys
+   * @param unspents - Chain, index, and value for each input
+   */
+  static fromHalfSignedLegacyTransaction(
+    txBytes: Uint8Array,
+    network: NetworkName,
+    walletKeys: WalletKeysArg,
+    unspents: HydrationUnspent[],
+  ): BitGoPsbt {
+    const keys = RootWalletKeys.from(walletKeys);
+    const wasm = WasmBitGoPsbt.from_half_signed_legacy_transaction(
+      txBytes,
+      network,
+      keys.wasm,
+      unspents,
+    );
+    return new BitGoPsbt(wasm);
+  }
+
   /**
    * Add an input to the PSBT
    *

packages/wasm-utxo/js/fixedScriptWallet/index.ts

@@ -31,6 +31,7 @@ export {
   type AddWalletOutputOptions,
   type ParseTransactionOptions,
   type ParseOutputsOptions,
+  type HydrationUnspent,
 } from "./BitGoPsbt.js";
 
 // Zcash-specific PSBT subclass

packages/wasm-utxo/js/index.ts

@@ -86,10 +86,41 @@ declare module "./wasm/wasm_utxo.js" {
   interface PsbtOutputDataWithAddress extends PsbtOutputData {
     address: string;
   }
+
+  /** Outpoint referencing a previous transaction output */
+  interface TxOutPoint {
+    txid: string;
+    vout: number;
+  }
+
+  /** Raw transaction input data returned by Transaction.getInputs() */
+  interface TxInputData {
+    previousOutput: TxOutPoint;
+    sequence: number;
+    scriptSig: Uint8Array;
+    witness: Uint8Array[];
+  }
+
+  /** Raw transaction output data returned by Transaction.getOutputs() */
+  interface TxOutputData {
+    script: Uint8Array;
+    value: bigint;
+  }
+
+  /** Transaction output data with resolved address */
+  interface TxOutputDataWithAddress extends TxOutputData {
+    address: string;
+  }
 }
 
 export { WrapDescriptor as Descriptor } from "./wasm/wasm_utxo.js";
 export { WrapMiniscript as Miniscript } from "./wasm/wasm_utxo.js";
 export { Psbt } from "./descriptorWallet/Psbt.js";
-export { DashTransaction, Transaction, ZcashTransaction } from "./transaction.js";
+export {
+  DashTransaction,
+  Transaction,
+  ZcashTransaction,
+  type ITransaction,
+  type ITransactionCommon,
+} from "./transaction.js";
 export { hasPsbtMagic, type IPsbt, type IPsbtWithAddress } from "./psbt.js";

packages/wasm-utxo/js/psbt.ts

@@ -1,15 +1,10 @@
 import type { PsbtInputData, PsbtOutputData, PsbtOutputDataWithAddress } from "./wasm/wasm_utxo.js";
 import type { BIP32 } from "./bip32.js";
+import type { ITransactionCommon } from "./transaction.js";
 
 /** Common interface for PSBT types */
-export interface IPsbt {
-  inputCount(): number;
-  outputCount(): number;
-  getInputs(): PsbtInputData[];
-  getOutputs(): PsbtOutputData[];
+export interface IPsbt extends ITransactionCommon<PsbtInputData, PsbtOutputData> {
   getGlobalXpubs(): BIP32[];
-  version(): number;
-  lockTime(): number;
   unsignedTxId(): string;
   addInputAtIndex(
     index: number,

packages/wasm-utxo/js/transaction.ts

@@ -1,11 +1,28 @@
-import { WasmDashTransaction, WasmTransaction, WasmZcashTransaction } from "./wasm/wasm_utxo.js";
+import {
+  WasmDashTransaction,
+  WasmTransaction,
+  WasmZcashTransaction,
+  type TxInputData,
+  type TxOutputData,
+  type TxOutputDataWithAddress,
+} from "./wasm/wasm_utxo.js";
+import type { CoinName } from "./coinName.js";
 
-/**
- * Common interface for all transaction types
- */
-export interface ITransaction {
+/** Common read-only interface shared by transactions and PSBTs */
+export interface ITransactionCommon<TInput, TOutput> {
+  inputCount(): number;
+  outputCount(): number;
+  version(): number;
+  lockTime(): number;
+  getInputs(): TInput[];
+  getOutputs(): TOutput[];
+}
+
+/** Common interface for all transaction types */
+export interface ITransaction extends ITransactionCommon<TxInputData, TxOutputData> {
   toBytes(): Uint8Array;
   getId(): string;
+  getOutputsWithAddress(coin: CoinName): TxOutputDataWithAddress[];
 }
 
 /**
@@ -27,9 +44,7 @@ export class Transaction implements ITransaction {
     return new Transaction(WasmTransaction.from_bytes(bytes));
   }
 
-  /**
-   * @internal Create from WASM instance directly (avoids re-parsing bytes)
-   */
+  /** @internal Create from WASM instance directly (avoids re-parsing bytes) */
   static fromWasm(wasm: WasmTransaction): Transaction {
     return new Transaction(wasm);
   }
@@ -84,9 +99,35 @@ export class Transaction implements ITransaction {
     return this._wasm.get_vsize();
   }
 
-  /**
-   * @internal
-   */
+  inputCount(): number {
+    return this._wasm.input_count();
+  }
+
+  outputCount(): number {
+    return this._wasm.output_count();
+  }
+
+  version(): number {
+    return this._wasm.version();
+  }
+
+  lockTime(): number {
+    return this._wasm.lock_time();
+  }
+
+  getInputs(): TxInputData[] {
+    return this._wasm.get_inputs() as TxInputData[];
+  }
+
+  getOutputs(): TxOutputData[] {
+    return this._wasm.get_outputs() as TxOutputData[];
+  }
+
+  getOutputsWithAddress(coin: CoinName): TxOutputDataWithAddress[] {
+    return this._wasm.get_outputs_with_address(coin) as TxOutputDataWithAddress[];
+  }
+
+  /** @internal */
   get wasm(): WasmTransaction {
     return this._wasm;
   }
@@ -104,9 +145,7 @@ export class ZcashTransaction implements ITransaction {
     return new ZcashTransaction(WasmZcashTransaction.from_bytes(bytes));
   }
 
-  /**
-   * @internal Create from WASM instance directly (avoids re-parsing bytes)
-   */
+  /** @internal Create from WASM instance directly (avoids re-parsing bytes) */
   static fromWasm(wasm: WasmZcashTransaction): ZcashTransaction {
     return new ZcashTransaction(wasm);
   }
@@ -127,9 +166,35 @@ export class ZcashTransaction implements ITransaction {
     return this._wasm.get_txid();
   }
 
-  /**
-   * @internal
-   */
+  inputCount(): number {
+    return this._wasm.input_count();
+  }
+
+  outputCount(): number {
+    return this._wasm.output_count();
+  }
+
+  version(): number {
+    return this._wasm.version();
+  }
+
+  lockTime(): number {
+    return this._wasm.lock_time();
+  }
+
+  getInputs(): TxInputData[] {
+    return this._wasm.get_inputs() as TxInputData[];
+  }
+
+  getOutputs(): TxOutputData[] {
+    return this._wasm.get_outputs() as TxOutputData[];
+  }
+
+  getOutputsWithAddress(coin: CoinName): TxOutputDataWithAddress[] {
+    return this._wasm.get_outputs_with_address(coin) as TxOutputDataWithAddress[];
+  }
+
+  /** @internal */
   get wasm(): WasmZcashTransaction {
     return this._wasm;
   }
@@ -147,9 +212,7 @@ export class DashTransaction implements ITransaction {
     return new DashTransaction(WasmDashTransaction.from_bytes(bytes));
   }
 
-  /**
-   * @internal Create from WASM instance directly (avoids re-parsing bytes)
-   */
+  /** @internal Create from WASM instance directly (avoids re-parsing bytes) */
   static fromWasm(wasm: WasmDashTransaction): DashTransaction {
     return new DashTransaction(wasm);
   }
@@ -170,9 +233,35 @@ export class DashTransaction implements ITransaction {
     return this._wasm.get_txid();
   }
 
-  /**
-   * @internal
-   */
+  inputCount(): number {
+    return this._wasm.input_count();
+  }
+
+  outputCount(): number {
+    return this._wasm.output_count();
+  }
+
+  version(): number {
+    return this._wasm.version();
+  }
+
+  lockTime(): number {
+    return this._wasm.lock_time();
+  }
+
+  getInputs(): TxInputData[] {
+    return this._wasm.get_inputs() as TxInputData[];
+  }
+
+  getOutputs(): TxOutputData[] {
+    return this._wasm.get_outputs() as TxOutputData[];
+  }
+
+  getOutputsWithAddress(coin: CoinName): TxOutputDataWithAddress[] {
+    return this._wasm.get_outputs_with_address(coin) as TxOutputDataWithAddress[];
+  }
+
+  /** @internal */
   get wasm(): WasmDashTransaction {
     return this._wasm;
   }