docs: add more comments around the create-fuels template app

templates/nextjs/fuels.config.ts

@@ -6,11 +6,12 @@ dotenv.config({
   path: ['.env.local', '.env'],
 });
 
+// If your node is running on a port other than 4000, you can set it here
 const fuelCorePort = +(process.env.NEXT_PUBLIC_FUEL_NODE_PORT as string) || 4000;
 
 export default createConfig({
-  workspace: './sway-programs',
-  output: './src/sway-api',
+  workspace: './sway-programs', // Path to your Sway workspace
+  output: './src/sway-api', // Where your generated types will be saved
   fuelCorePort,
   providerUrl: NODE_URL,
   forcPath: 'fuels-forc',

templates/nextjs/src/app/faucet/page.tsx

@@ -9,7 +9,7 @@ import { useEffect, useState } from "react";
 import toast from "react-hot-toast";
 
 export default function Faucet() {
-  const { faucetWallet } = useFaucet();
+  const { faucetWallet } = useFaucet(); // Get the faucet wallet instance from the useFaucet hook
   const { wallet, refreshWalletBalance } = useActiveWallet();
 
   const [receiverAddress, setReceiverAddress] = useState<string>("");
@@ -34,6 +34,7 @@ export default function Faucet() {
       return toast.error("Amount cannot be empty");
     }
 
+    // Transfer the specified amount of ETH to the receiver address
     const tx = await faucetWallet.transfer(
       receiverAddress,
       bn.parseUnits(amountToSend.toString()),

templates/nextjs/src/app/layout.tsx

@@ -17,6 +17,7 @@ import {
 import { NODE_URL } from "@/lib";
 import { ActiveWalletProvider } from "@/hooks/useActiveWallet";
 
+// react-query is a peer dependency of @fuels/react, so we set it up here. See https://docs.fuel.network/docs/wallet/dev/getting-started/#installation-1
 const queryClient = new QueryClient();
 
 interface RootLayoutProps {
@@ -25,12 +26,13 @@ interface RootLayoutProps {
 
 export default function RootLayout({ children }: RootLayoutProps) {
   const [isMounted, setIsMounted] = useState(false);
-  const providerToUse = useMemo(() => Provider.create(NODE_URL), [NODE_URL]);
+  const providerToUse = useMemo(() => Provider.create(NODE_URL), [NODE_URL]); // Create a Provider instance. We memoize it to avoid creating a new instance on every render.
 
   useEffect(() => {
     setIsMounted(true);
   }, []);
 
+  // Only render the component if the page has been mounted, and `window` is defined.
   if (!isMounted) return null;
 
   return (
@@ -40,6 +42,7 @@ export default function RootLayout({ children }: RootLayoutProps) {
           <QueryClientProvider client={queryClient}>
             <FuelProvider
               fuelConfig={{
+                // The list of wallet connectors. You can add or remove connectors from here based on your needs.
                 connectors: [
                   new FuelWalletConnector(),
                   new BurnerWalletConnector({

templates/nextjs/src/app/page.tsx

@@ -29,8 +29,11 @@ export default function Home() {
    */
   useAsync(async () => {
     if (wallet) {
+      // Create a new instance of the contract
       const testContract = TestContractAbi__factory.connect(contractId, wallet);
       setContract(testContract);
+
+      // Read the current value of the counter
       const { value } = await testContract.functions.get_count().get();
       setCounter(value.toNumber());
     }
@@ -48,10 +51,12 @@ export default function Home() {
       );
     }
 
+    // Call the increment_counter function on the contract
     const { waitForResult } = await contract.functions
       .increment_counter(bn(1))
       .call();
 
+    // Wait for the transaction to be mined, and then read the value returned by the contract call
     const { value } = await waitForResult();
 
     setCounter(value.toNumber());

templates/nextjs/src/app/predicate/page.tsx

@@ -26,6 +26,7 @@ export default function PredicateExample() {
   useAsync(async () => {
     if (wallet) {
       baseAssetId = wallet.provider.getBaseAssetId();
+      // Initialize a new predicate instance
       const predicate = TestPredicateAbi__factory.createInstance(
         wallet.provider,
       );
@@ -63,6 +64,7 @@ export default function PredicateExample() {
         return toast.error("Wallet not loaded");
       }
 
+      // Initialize a new predicate instance with the entered pin
       const reInitializePredicate = TestPredicateAbi__factory.createInstance(
         wallet.provider,
         [bn(pin)],
@@ -72,6 +74,11 @@ export default function PredicateExample() {
         return toast.error("Failed to initialize predicate");
       }
 
+      /*
+        Try to 'unlock' the predicate and transfer the funds back to the wallet.
+        If the pin is correct, this transfer transaction will succeed.
+        If the pin is incorrect, this transaction will fail.
+       */
       const tx = await reInitializePredicate.transfer(
         wallet.address,
         amount,

templates/nextjs/src/app/script/page.tsx

@@ -20,6 +20,7 @@ export default function ScriptExample() {
 
   useAsync(async () => {
     if (wallet) {
+      // Initialize script instance
       const script = TestScriptAbi__factory.createInstance(wallet);
       setScript(script);
     }
@@ -31,6 +32,7 @@ export default function ScriptExample() {
         return toast.error("Script not loaded");
       }
 
+      // Call the script with the input value
       const { waitForResult } = await script.functions.main(bn(input)).call();
       const { value } = await waitForResult();
 

templates/nextjs/src/components/Layout.tsx

@@ -29,6 +29,7 @@ export const Layout = ({ children }: { children: React.ReactNode }) => {
       return console.error("Unable to topup wallet because wallet is not set.");
     }
 
+    // If the current environment is local, transfer 5 ETH to the wallet from the local faucet wallet
     if (CURRENT_ENVIRONMENT === "local") {
       if (!faucetWallet) {
         return toast.error("Faucet wallet not found.");
@@ -45,6 +46,7 @@ export const Layout = ({ children }: { children: React.ReactNode }) => {
       return await refreshWalletBalance?.();
     }
 
+    // If the current environment is testnet, open the testnet faucet link in a new tab
     if (CURRENT_ENVIRONMENT === "testnet") {
       return window.open(
         `${TESTNET_FAUCET_LINK}?address=${wallet.address.toAddress()}`,

templates/nextjs/src/hooks/useActiveWallet.tsx

@@ -6,6 +6,9 @@ import { AppWallet } from "@/lib";
 /**
  * burner -> a burner wallet embedded inside of the template app and stored in local storage
  * browser -> a wallet connected via a browser extension like the Fuel Wallet
+ *
+ * Whenever a browser wallet is connected, this hook will return an instance of the browser wallet.
+ * Otherwise, it will return an instance of a local burner wallet.
  */
 type WalletTypes = "burner" | "browser";
 

templates/nextjs/src/hooks/useBrowserWallet.tsx

@@ -9,6 +9,9 @@ interface BrowserWallet extends AppWallet {
   network: any;
 }
 
+/**
+ * This hook returns an instance of the browser wallet connected via any of the supported connectors.
+ **/
 export const useBrowserWallet: () => BrowserWallet = () => {
   const { wallet } = useWallet();
   const [browserWalletBalance, setBrowserWalletBalance] = useState<BN>();

templates/nextjs/src/hooks/useBurnerWallet.tsx

@@ -5,6 +5,9 @@ import useAsync from "react-use/lib/useAsync";
 
 const BURNER_WALLET_LOCAL_STORAGE_KEY = "create-fuels-burner-wallet-pk";
 
+/**
+ * This hook returns an instance of a burner wallet that lives in local storage.
+ */
 export const useBurnerWallet: () => AppWallet = () => {
   const [burnerWallet, setBurnerWallet] = useState<WalletUnlocked>();
   const [burnerWalletBalance, setBurnerWalletBalance] = useState<BN>();

templates/nextjs/src/hooks/useFaucet.tsx

@@ -3,6 +3,10 @@ import { Provider, Wallet, WalletUnlocked } from "fuels";
 import { useState } from "react";
 import useAsync from "react-use/lib/useAsync";
 
+/**
+ * This hook returns an instance of a faucet wallet.
+ * The value of `FAUCET_PRIVATE_KEY` depends on your chain config.
+ */
 export const useFaucet = () => {
   const [faucetWallet, setFaucetWallet] = useState<WalletUnlocked>();
 

templates/nextjs/src/lib.ts

@@ -1,14 +1,17 @@
 import { Account, BN, TESTNET_NETWORK_URL } from 'fuels';
 
+// The two environments for the dapp are local and testnet.
 export const Environments = {
   LOCAL: 'local',
   TESTNET: 'testnet',
 } as const;
 type Environment = (typeof Environments)[keyof typeof Environments];
 
+// The current environment is determined by the `NEXT_PUBLIC_DAPP_ENVIRONMENT` environment variable. If it's not set, the default is `local`.
 export const CURRENT_ENVIRONMENT: Environment =
   (process.env.NEXT_PUBLIC_DAPP_ENVIRONMENT as Environment) || Environments.LOCAL;
 
+// The node URL is determined by the current environment too.
 export const NODE_URL =
   CURRENT_ENVIRONMENT === Environments.LOCAL
     ? `http://127.0.0.1:${process.env.NEXT_PUBLIC_FUEL_NODE_PORT || 4000}/v1/graphql`

templates/nextjs/sway-programs/contract/src/main.sw

@@ -1,5 +1,6 @@
 contract;
 
+// The abi defines the blueprint for the contract.
 abi Counter {
     #[storage(read)]
     fn get_count() -> u64;
@@ -8,16 +9,19 @@ abi Counter {
     fn increment_counter(amount: u64) -> u64;
 }
 
+// The storage variables for the contract. In this case, there is only one variable called `counter` which is initialized to 0.
 storage {
     counter: u64 = 0,
 }
 
 impl Counter for Contract {
+    // The `get_count` function returns the current value of the counter.
     #[storage(read)]
     fn get_count() -> u64 {
         storage.counter.read()
     }
 
+    // The `increment_counter` function increments the counter by the given amount.
     #[storage(write, read)]
     fn increment_counter(amount: u64) -> u64 {
         let current = storage.counter.read();

templates/nextjs/sway-programs/predicate/src/main.sw

@@ -1,5 +1,6 @@
 predicate;
 
+// This predicate checks if the given password is 1337. If it is, the predicate is 'unlocked' and the transaction is allowed to proceed. Otherwise, it is reverted.
 fn main(password: u64) -> bool {
     return password == 1337;
 }

templates/nextjs/sway-programs/script/src/main.sw

@@ -1,5 +1,6 @@
 script;
 
+// This script simply returns the input value.
 fn main(input: u64) -> u64 {
     return input;
 }