create the CanvasOnchain contract and write the test

package.json

@@ -38,6 +38,7 @@
   },
   "packageManager": "[email protected]",
   "devDependencies": {
+    "@nomicfoundation/hardhat-network-helpers": "^1.0.12",
     "husky": "^9.1.6",
     "lint-staged": "^15.2.10"
   },

packages/hardhat/contracts/CanvasOnchain.sol

@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+
+import "@openzeppelin/contracts/access/Ownable.sol";
+
+contract PixelCanvas is Ownable {
+    // Canvas Dimensions
+    uint256 public constant CANVAS_WIDTH = 64;
+    uint256 public constant CANVAS_HEIGHT = 64;
+
+    // Color Palette (Limited Options)
+    enum Color {
+        WHITE,
+        BLACK,
+        RED,
+        GREEN,
+        BLUE,
+        YELLOW,
+        PURPLE,
+        ORANGE
+    }
+
+    // Pixel Structure
+    struct Pixel {
+        address author;
+        Color color;
+        uint256 timestamp;
+    }
+
+    // 2D Mapping to store pixels
+    Pixel[CANVAS_WIDTH][CANVAS_HEIGHT] public canvas;
+
+    // Events
+    event PixelPlaced(address indexed author, uint256 x, uint256 y, Color color);
+
+    // Constructor to initialize default Buidlguidl Batch11 drawing
+    constructor() Ownable(msg.sender){
+
+        // Initial drawing representing Buidlguidl Batch11 logo
+        initializeBuidlGuidlLogo();
+    }
+
+    /**
+     * @dev Initialize a default Buidlguidl Batch11 inspired pixel art
+     * This is a simplified representation and can be customized
+     */
+    function initializeBuidlGuidlLogo() private {
+        // B letter representation
+        for (uint256 x = 10; x < 20; x++) {
+            for (uint256 y = 10; y < 50; y++) {
+                canvas[x][y] = Pixel({
+                    author: owner(),
+                    color: Color.BLUE,
+                    timestamp: block.timestamp
+                });
+            }
+        }
+
+        // 11 representation with some pixels
+        for (uint256 x = 30; x < 40; x++) {
+            for (uint256 y = 20; y < 30; y++) {
+                canvas[x][y] = Pixel({
+                    author: owner(),
+                    color: Color.GREEN,
+                    timestamp: block.timestamp
+                });
+            }
+        }
+
+        // Add some distinctive pixels to represent Buidlguidl spirit
+        canvas[32][25] = Pixel({
+            author: owner(),
+            color: Color.RED,
+            timestamp: block.timestamp
+        });
+    }
+
+    /**
+     * @dev Place a pixel on the canvas
+     * @param x X-coordinate of the pixel
+     * @param y Y-coordinate of the pixel
+     * @param color Color of the pixel
+     */
+    function placePixel(uint256 x, uint256 y, Color color) external {
+        // Validate pixel coordinates
+        require(x < CANVAS_WIDTH, "X coordinate out of bounds");
+        require(y < CANVAS_HEIGHT, "Y coordinate out of bounds");
+
+        // Update pixel
+        canvas[x][y] = Pixel({
+            author: msg.sender,
+            color: color,
+            timestamp: block.timestamp
+        });
+
+        // Emit event
+        emit PixelPlaced(msg.sender, x, y, color);
+    }
+
+    /**
+     * @dev Get pixel information
+     * @param x X-coordinate of the pixel
+     * @param y Y-coordinate of the pixel
+     * @return Pixel details
+     */
+    function getPixel(uint256 x, uint256 y) external view returns (Pixel memory) {
+        require(x < CANVAS_WIDTH, "X coordinate out of bounds");
+        require(y < CANVAS_HEIGHT, "Y coordinate out of bounds");
+        return canvas[x][y];
+    }
+
+
+
+
+    /**
+     * @dev Get canvas snapshot (useful for viewing entire canvas)
+     * @return Array of pixels
+     */
+    function getCanvasSnapshot() external view returns (Pixel[CANVAS_WIDTH][CANVAS_HEIGHT] memory) {
+        return canvas;
+    }
+}

packages/hardhat/hardhat.config.ts

@@ -7,6 +7,7 @@ import "@typechain/hardhat";
 import "hardhat-gas-reporter";
 import "solidity-coverage";
 import "@nomicfoundation/hardhat-verify";
+import "@nomicfoundation/hardhat-network-helpers";
 import "hardhat-deploy";
 import "hardhat-deploy-ethers";
 

packages/hardhat/test/CanvasOnchain.ts

@@ -0,0 +1,83 @@
+import { loadFixture } from "@nomicfoundation/hardhat-network-helpers";
+import { expect } from "chai";
+import hre from "hardhat";
+
+describe("PixelCanvas", function () {
+  async function deployPixelCanvas() {
+    const [owner, user1, user2] = await hre.ethers.getSigners();
+    const pixel = await hre.ethers.getContractFactory("PixelCanvas");
+    const Pixel = await pixel.deploy();
+    return { owner, user1, user2, Pixel };
+  }
+
+  describe("Deployment", function () {
+    it("Should set the correct owner", async function () {
+      const { owner, Pixel } = await loadFixture(deployPixelCanvas);
+      expect(await Pixel.owner()).to.equal(owner.address);
+    });
+
+    it("Should initialize canvas with predefined pixels", async function () {
+      // Check a few predefined pixels from initializeBuidlGuidlLogo()
+      const { owner, Pixel } = await loadFixture(deployPixelCanvas);
+      const bluePixel = await Pixel.canvas(15, 25);
+      expect(bluePixel.color).to.equal(4); // Blue is enum index 1
+      expect(bluePixel.author).to.equal(owner.address);
+    });
+  });
+
+  describe("Pixel Placement", function () {
+    it("Should allow placing a pixel", async function () {
+      const x = 10;
+      const y = 20;
+      const color = 2; // Red from enum
+      const { user1, Pixel } = await loadFixture(deployPixelCanvas);
+      // Place pixel from user1
+      await Pixel.connect(user1).placePixel(x, y, color);
+
+      const pixel = await Pixel.canvas(x, y);
+      expect(pixel.author).to.equal(user1.address);
+      expect(pixel.color).to.equal(color);
+    });
+
+    it("Should reject out-of-bounds pixel placement", async function () {
+      const { Pixel } = await loadFixture(deployPixelCanvas);
+      await expect(Pixel.placePixel(64, 10, 0)).to.be.revertedWith("X coordinate out of bounds");
+
+      await expect(Pixel.placePixel(10, 64, 0)).to.be.revertedWith("Y coordinate out of bounds");
+    });
+
+    it("Should emit PixelPlaced event", async function () {
+      const x = 30;
+      const y = 40;
+
+      const color = 3; // Green from enum
+      const { user1, Pixel } = await loadFixture(deployPixelCanvas);
+      await expect(Pixel.connect(user1).placePixel(x, y, color))
+        .to.emit(Pixel, "PixelPlaced")
+        .withArgs(user1.address, x, y, color);
+    });
+  });
+
+  describe("Pixel Retrieval", function () {
+    it("Should retrieve pixel information", async function () {
+      const x = 12;
+      const y = 15;
+      const color = 4; // Blue from enum
+      const { user1, Pixel } = await loadFixture(deployPixelCanvas);
+      await Pixel.connect(user1).placePixel(x, y, color);
+
+      const pixel = await Pixel.getPixel(x, y);
+      expect(pixel.author).to.equal(user1.address);
+      expect(pixel.color).to.equal(color);
+    });
+  });
+
+  describe("Canvas Snapshot", function () {
+    it("Should return full canvas snapshot", async function () {
+      const { Pixel } = await loadFixture(deployPixelCanvas);
+      const snapshot = await Pixel.getCanvasSnapshot();
+      expect(snapshot.length).to.equal(64);
+      expect(snapshot[0].length).to.equal(64);
+    });
+  });
+});

yarn.lock

@@ -1739,6 +1739,17 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@nomicfoundation/hardhat-network-helpers@npm:^1.0.12":
+  version: 1.0.12
+  resolution: "@nomicfoundation/hardhat-network-helpers@npm:1.0.12"
+  dependencies:
+    ethereumjs-util: ^7.1.4
+  peerDependencies:
+    hardhat: ^2.9.5
+  checksum: 7e1b91789dd4e73464b4eec919b1e67c6d482dd7534f4f7cae73fb5bdddd69f2a47143754b34385b098a1df0f4875cd4d2e1109fc3d847db76f4b0a9a44bd959
+  languageName: node
+  linkType: hard
+
 "@nomicfoundation/hardhat-verify@npm:^2.0.10":
   version: 2.0.10
   resolution: "@nomicfoundation/hardhat-verify@npm:2.0.10"
@@ -11941,6 +11952,7 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "se-2@workspace:."
   dependencies:
+    "@nomicfoundation/hardhat-network-helpers": ^1.0.12
     husky: ^9.1.6
     lint-staged: ^15.2.10
     react-icons: ^5.3.0