Added a State Machine Pattern

contracts/solidity_patterns/StateMachine.sol

@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.9;
+
+import "@nilfoundation/smart-contracts/contracts/NilBase.sol";
+
+contract StateMachine is NilBase {
+    enum Stages {
+        Initialize,
+        Processing,
+        Completed,
+        Failed
+    }
+
+    Stages public currentStage;
+
+    uint256 public processValue;
+    mapping(address => bool) public hasParticipated;
+
+    event StageAdvanced(Stages newStage);
+    event ProcessValueUpdated(uint256 newValue);
+
+    modifier atStage(Stages _stage) {
+        require(currentStage == _stage, "Invalid stage");
+        _;
+    }
+
+    modifier transitionAfter() {
+        _;
+        _nextStage();
+    }
+
+    constructor() {
+        currentStage = Stages.Initialize;
+    }
+
+    function startProcess() external atStage(Stages.Initialize) transitionAfter {
+        processValue = 0;
+        emit ProcessValueUpdated(processValue);
+    }
+
+    function participate() external atStage(Stages.Processing) {
+        require(!hasParticipated[msg.sender], "Already participated");
+
+        hasParticipated[msg.sender] = true;
+        processValue += 1;
+
+        emit ProcessValueUpdated(processValue);
+
+        if (processValue >= 5) {
+            currentStage = Stages.Completed;
+            emit StageAdvanced(Stages.Completed);
+        }
+    }
+
+    function _nextStage() internal {
+        currentStage = Stages(uint(currentStage) + 1);
+        emit StageAdvanced(currentStage);
+    }
+
+    function reset() external onlyInternal {
+        require(currentStage == Stages.Completed || currentStage == Stages.Failed, 
+                "Can only reset from Completed or Failed state");
+        currentStage = Stages.Initialize;
+        processValue = 0;
+        emit StageAdvanced(Stages.Initialize);
+        emit ProcessValueUpdated(processValue);
+    }
+} 

scripts/cli.js

@@ -51,9 +51,22 @@ function copyFile(srcFilePath, destFilePath) {
     }
 }
 
+function addPatternCommand() {
+    const packageJsonPath = path.join(projectPath, 'package.json');
+    const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf-8'));
+
+    // Add create-pattern command to scripts
+    packageJson.scripts = packageJson.scripts || {};
+    packageJson.scripts['create-pattern'] = 'node scripts/create-pattern.js';
+
+    fs.writeFileSync(packageJsonPath, JSON.stringify(packageJson, null, 2));
+}
+
 createPackageJson(templatePath, projectPath);
 copyFile('.env.example', '.env');
 copyFile('ignition/modules/Incrementer.ts', 'ignition/modules/Incrementer.ts');
 copyFile('contracts/Incrementer.sol', 'contracts/Incrementer.sol');
+copyFile('scripts/create-pattern.js', 'scripts/create-pattern.js');
+addPatternCommand();
 
 console.log('Project setup complete!');

scripts/create-pattern.js

@@ -0,0 +1,40 @@
+#!/usr/bin/env node
+const fs = require('fs');
+const path = require('path');
+
+const PATTERNS = {
+    'access': 'AccessRestriction.sol',
+    'state': 'StateMachine.sol',
+    'guard': 'GuardCheck.sol',
+    'proxy': 'ProxyDelegate.sol',
+    'check': 'CheckEffectsInteraction.sol'
+};
+
+function createPattern(patternName, projectPath) {
+    if (!PATTERNS[patternName]) {
+        console.error(`Invalid pattern name. Available patterns: ${Object.keys(PATTERNS).join(', ')}`);
+        process.exit(1);
+    }
+
+    const templatePath = path.join(__dirname, '..', 'contracts', 'solidity_patterns', PATTERNS[patternName]);
+    const destPath = path.join(projectPath, 'contracts', 'patterns', PATTERNS[patternName]);
+
+    // Create directories if they don't exist
+    fs.mkdirSync(path.join(projectPath, 'contracts', 'patterns'), { recursive: true });
+
+    // Copy pattern file
+    fs.copyFileSync(templatePath, destPath);
+    console.log(`Created ${patternName} pattern at: ${destPath}`);
+}
+
+// Get command line arguments
+const patternName = process.argv[2];
+const projectDir = process.argv[3] || '.';
+
+if (!patternName) {
+    console.error('Please specify a pattern name');
+    console.log(`Available patterns: ${Object.keys(PATTERNS).join(', ')}`);
+    process.exit(1);
+}
+
+createPattern(patternName.toLowerCase(), path.resolve(projectDir));