Adding a puzzle

We're going to make a new puzzle, which means we need to provide the smart contract with a set of clues and info about the answers.

Of course, we'll not be sending the answers to the smart contract, otherwise everyone could see. We will, however, send details about each clue, including:

The clue number
Whether it's a down or across clue
The coordinates (x and y position)
The length of the clue. (How many letters)

Essentially, we're going to tell the smart contract enough information for an empty puzzle like this:

Blank crossword for chapter 2 of the crossword puzzle smart contract tutorial

(Note that we aren't showing the human-readable clues in the above screenshot, but we will provide that as well.)

Building and deploying#

Let's use the same steps we learned from the first chapter:

Teacher shows chalkboard with instructions on how to properly deploy a smart contract. 1. Build smart contract. 2. Create a subaccount (or delete and recreate if it exists) 3. Deploy to subaccount. 4. Interact. Art created by herogranada.near — Art by herogranada.near

Navigate to the contract directory, then run the build script for your system:

./build.sh

If following from the previous chapter, you'll likely have a subaccount already created. For the purpose of demonstration, we're calling the subaccount (where we deploy the contract) crossword.friend.testnet and the parent account is thus friend.testnet.

Let's delete the subaccount and recreate it, to start from a blank slate.

Animation of an alien in space with a computer deleting and re-writing the account crossword.friend.testnet Art by 3one9.near — Art by 3one9.near

Here's how to delete and recreate the subaccount using NEAR CLI:

# Delete the subaccount and send remaining balance to friend.testnet
near delete crossword.friend.testnet friend.testnet
# Create the subaccount again 
near create-account crossword.friend.testnet --masterAccount friend.testnet
# Deploy, calling the "new" method with the the parameter for owner_id
near deploy crossword.friend.testnet --wasmFile res/crossword_tutorial_chapter_2.wasm --initFunction new --initArgs '{"owner_id": "crossword.friend.testnet"}'

Now we're ready to construct our new crossword puzzle and add it via the new_puzzle method. Let's start with the clues for this new puzzle.

The clues#

We're going to use these clues below for our improved puzzle. The Answer column will not get sent to the smart contract when we call new_puzzle.

Number	Answer	Clue	(x, y) coords	length
1	paras	NFT market on NEAR that specializes in cards and comics.	(1, 1)	5
2	rainbowbridge	You can move assets between NEAR and different chains, including Ethereum, by visiting __.app	(0, 2)	13
3	mintbase	NFT market on NEAR with art, physical items, tickets, and more.	(9, 1)	8
4	yoctonear	The smallest denomination of the native token on NEAR.	(3, 8)	9
5	cli	You typically deploy a smart contract with the NEAR ___ tool.	(5, 8)	3

The x and y coordinates have their origin in the upper-left side of the puzzle grid, and each row and column start at 0.

Solution hash#

Let's derive the sha256 hash using an easy online tool (there are many other offline methods as well) to discover the solution hash:

d1a5cf9ad1adefe0528f7d31866cf901e665745ff172b96892693769ad284010

Add the puzzle#

Add a new puzzle using NEAR CLI with this long command, replacing crossword.friend.testnet with your subaccount:

near call crossword.friend.testnet new_puzzle '{
  "solution_hash": "d1a5cf9ad1adefe0528f7d31866cf901e665745ff172b96892693769ad284010",
  "answers": [
   {
     "num": 1,
     "start": {
       "x": 1,
       "y": 1
     },
     "direction": "Down",
     "length": 5,
     "clue": "NFT market on NEAR that specializes in cards and comics."
   },
   {
     "num": 2,
     "start": {
       "x": 0,
       "y": 2
     },
     "direction": "Across",
     "length": 13,
     "clue": "You can move assets between NEAR and different chains, including Ethereum, by visiting ______.app"
   },
   {
     "num": 3,
     "start": {
       "x": 9,
       "y": 1
     },
     "direction": "Down",
     "length": 8,
     "clue": "NFT market on NEAR with art, physical items, tickets, and more."
   },
   {
     "num": 4,
     "start": {
       "x": 3,
       "y": 8
     },
     "direction": "Across",
     "length": 9,
     "clue": "The smallest denomination of the native token on NEAR."
   },
   {
     "num": 5,
     "start": {
       "x": 5,
       "y": 8
     },
     "direction": "Down",
     "length": 3,
     "clue": "You typically deploy a smart contract with the NEAR ___ tool."
   }
  ]
}' --accountId crossword.friend.testnet

Note that our contract name and the account we're calling this from are both crossword.friend.testnet. That's because we added a check at the top of new_puzzle to make sure the predecessor is the owner_id.

Now our smart contract has information about this second crossword puzzle.

Let's explore how to make our frontend have a login button and truly turn this into a decentralized app (dApp)!