Add makeTx function with NetworkProvider interface

integrations/javascript/@planetarium/lib9c/README.md

@@ -3,3 +3,25 @@
 This npm package provides functions to build actions equivalent to [Lib9c].
 
 [Lib9c]: https://github.com/planetarium/lib9c
+
+## Usage Example
+
+```typescript
+import { HeadlessNetworkProvider } from "@planetarium/9c-headless-network-provider";
+import { RawPrivateKey, Address } from "@planetarium/account";
+import { signTx } from "@planetarium/tx";
+import { makeTx, ClaimStakeReward } from "@planetarium/lib9c";
+
+const networkProvider = new HeadlessNetworkProvider("https://9c-main-full-state.nine-chronicles.com/graphql");
+const account = RawPrivateKey.generate();  // Temporary private key key.
+
+const unsignedTx = await makeTx(account, networkProvider, new ClaimStakeReward({
+  avatarAddress: Address.fromHex('<ADDRESS>'),
+}));
+
+console.log(unsignedTx);
+
+const signedTx = await signTx(unsignedTx, account);
+
+console.log(signedTx);
+```

integrations/javascript/@planetarium/lib9c/src/index.ts

@@ -64,3 +64,4 @@ export {
   type MigratePledgeToGuildArgs,
 } from "./actions/migrate_pledge_to_guild.js";
 export { MakeGuild } from "./actions/make_guild.js";
+export { makeTx, type NetworkProvider } from "./tx.js";

integrations/javascript/@planetarium/lib9c/src/tx.ts

@@ -0,0 +1,40 @@
+import { Buffer } from "buffer";
+import { type Account, Address } from "@planetarium/account";
+import type { UnsignedTx } from "@planetarium/tx";
+import type { PolymorphicAction } from "./actions/common.js";
+import { TransferAsset } from "./actions/transfer_asset.js";
+import { TransferAssets } from "./actions/transfer_assets.js";
+import { MEAD, fav } from "./models/currencies.js";
+
+export interface NetworkProvider {
+  getNextNonce(address: Address): Promise<bigint>;
+  getGenesisHash(): Promise<string>;
+}
+
+export async function makeTx(
+  account: Account,
+  provider: NetworkProvider,
+  action: PolymorphicAction,
+): Promise<UnsignedTx> {
+  const publicKey = await account.getPublicKey();
+  const signer = Address.deriveFrom(publicKey);
+  const nonce = await provider.getNextNonce(signer);
+  const genesisHash = await provider.getGenesisHash();
+
+  const gasLimit =
+    action instanceof TransferAsset || action instanceof TransferAssets
+      ? 4n
+      : 1n;
+
+  return {
+    nonce,
+    genesisHash: Buffer.from(genesisHash, "hex"),
+    signer: signer.toBytes(),
+    updatedAddresses: new Set(),
+    actions: [action.bencode()],
+    publicKey: publicKey.toBytes("uncompressed"),
+    timestamp: new Date(),
+    gasLimit,
+    maxGasPrice: fav(MEAD, 1n),
+  };
+}