feat: fix database connection & memory leaks, consolidate code duplication

Co-authored-by: cetinmustafa83 <30570791+cetinmustafa83@users.noreply.github.com>

scripts/audit-memory-leaks.mjs

@@ -0,0 +1,124 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const projectRoot = path.join(__dirname, '..');
+const srcDir = path.join(projectRoot, 'src');
+
+// Patterns indicating potential memory leaks
+const leakPatterns = {
+  uncleared_listeners: {
+    pattern: /addEventListener\s*\([^)]*\)/g,
+    warning: 'Event listener without removeEventListener cleanup'
+  },
+  uncleared_timers: {
+    pattern: /(setInterval|setTimeout)\s*\(/g,
+    warning: 'Timer without clear/clearInterval cleanup'
+  },
+  missing_cleanup: {
+    pattern: /useEffect\s*\(\s*\([^)]*\)\s*=>\s*\{[^}]*\},\s*\[\s*\]\s*\)/g,
+    warning: 'useEffect with empty dependency array but no cleanup'
+  },
+  unsubscribe: {
+    pattern: /\.subscribe\s*\([^)]*\)/g,
+    warning: 'Observable subscription without unsubscribe'
+  }
+};
+
+let issuesFound = 0;
+let filesScanned = 0;
+
+function scanFile(filePath) {
+  filesScanned++;
+  const content = fs.readFileSync(filePath, 'utf8');
+  const lines = content.split('\n');
+  
+  let fileIssues = 0;
+
+  // Check for uncleared event listeners
+  const hasAddEventListener = content.includes('addEventListener');
+  if (hasAddEventListener) {
+    const addCount = (content.match(/addEventListener/g) || []).length;
+    const removeCount = (content.match(/removeEventListener/g) || []).length;
+    if (addCount > removeCount) {
+      console.log(`\n⚠️  ${path.relative(projectRoot, filePath)}`);
+      console.log(`   Found ${addCount} addEventListener but only ${removeCount} removeEventListener`);
+      issuesFound++;
+      fileIssues++;
+    }
+  }
+
+  // Check for uncleared timers
+  const hasSetInterval = content.includes('setInterval');
+  if (hasSetInterval) {
+    const setCount = (content.match(/setInterval/g) || []).length;
+    const clearCount = (content.match(/clearInterval/g) || []).length;
+    if (setCount > clearCount) {
+      console.log(`\n⚠️  ${path.relative(projectRoot, filePath)}`);
+      console.log(`   Found ${setCount} setInterval but only ${clearCount} clearInterval`);
+      issuesFound++;
+      fileIssues++;
+    }
+  }
+
+  // Check for setTimeout without cleanup
+  const hasSetTimeout = content.includes('setTimeout');
+  if (hasSetTimeout && !content.includes('clearTimeout')) {
+    console.log(`\n⚠️  ${path.relative(projectRoot, filePath)}`);
+    console.log(`   Found setTimeout but no clearTimeout found`);
+    issuesFound++;
+    fileIssues++;
+  }
+
+  // Check for subscriptions without unsubscribe
+  const hasSubscribe = content.includes('.subscribe(');
+  if (hasSubscribe && !content.includes('.unsubscribe()')) {
+    console.log(`\n⚠️  ${path.relative(projectRoot, filePath)}`);
+    console.log(`   Found .subscribe() but no .unsubscribe() found`);
+    issuesFound++;
+    fileIssues++;
+  }
+
+  // Check for useEffect with empty deps but complex logic
+  const useEffectMatches = content.matchAll(/useEffect\s*\(\s*\([^)]*\)\s*=>\s*\{([^}]+)\},\s*\[\s*\]\s*\)/g);
+  for (const match of useEffectMatches) {
+    const body = match[1];
+    if (body.includes('addEventListener') || body.includes('setInterval') || body.includes('subscribe')) {
+      console.log(`\n⚠️  ${path.relative(projectRoot, filePath)}`);
+      console.log(`   useEffect with [] deps contains event/timer/subscription logic`);
+      issuesFound++;
+      fileIssues++;
+    }
+  }
+
+  return fileIssues;
+}
+
+function walkDirectory(dir) {
+  const files = fs.readdirSync(dir);
+  
+  for (const file of files) {
+    const filePath = path.join(dir, file);
+    const stat = fs.statSync(filePath);
+    
+    if (stat.isDirectory() && !file.startsWith('.') && file !== 'node_modules') {
+      walkDirectory(filePath);
+    } else if (file.endsWith('.tsx') || file.endsWith('.ts')) {
+      scanFile(filePath);
+    }
+  }
+}
+
+console.log('🔍 Memory Leak Audit\n');
+console.log(`Scanning ${srcDir}...\n`);
+
+walkDirectory(srcDir);
+
+console.log('\n' + '='.repeat(60));
+console.log(`\nResults:`);
+console.log(`- Files scanned: ${filesScanned}`);
+console.log(`- Issues found: ${issuesFound}`);
+console.log(`\n✅ Run 'npm run memory-fix' to auto-fix common issues\n`);
+
+process.exit(issuesFound > 0 ? 1 : 0);