Implement Phase 1.2: Database with encryption at rest and core infrastructure

Co-authored-by: southseact-3d <217551146+southseact-3d@users.noreply.github.com>

chat/src/database/connection.js

@@ -0,0 +1,143 @@
+/**
+ * Database connection module with SQLite support
+ * Uses better-sqlite3 for synchronous operations
+ * Note: SQLCipher support requires special compilation, using AES-256-GCM encryption at field level instead
+ */
+
+const Database = require('better-sqlite3');
+const path = require('path');
+const fs = require('fs');
+
+let db = null;
+let dbPath = null;
+
+/**
+ * Initialize database connection
+ * @param {string} databasePath - Path to the database file
+ * @param {Object} options - Database options
+ * @returns {Database} Database instance
+ */
+function initDatabase(databasePath, options = {}) {
+  if (db) {
+    return db;
+  }
+
+  dbPath = databasePath;
+  
+  // Ensure database directory exists
+  const dbDir = path.dirname(databasePath);
+  if (!fs.existsSync(dbDir)) {
+    fs.mkdirSync(dbDir, { recursive: true });
+  }
+
+  // Initialize database with options
+  const dbOptions = {
+    verbose: options.verbose ? console.log : null,
+    fileMustExist: false,
+    timeout: options.timeout || 5000,
+    ...options
+  };
+
+  db = new Database(databasePath, dbOptions);
+
+  // Enable WAL mode for better concurrency
+  if (options.walMode !== false) {
+    db.pragma('journal_mode = WAL');
+  }
+
+  // Set reasonable defaults
+  db.pragma('synchronous = NORMAL');
+  db.pragma('cache_size = -64000'); // 64MB cache
+  db.pragma('temp_store = MEMORY');
+  db.pragma('foreign_keys = ON');
+
+  console.log('✅ Database connected:', databasePath);
+  
+  return db;
+}
+
+/**
+ * Get database instance
+ * @returns {Database|null} Database instance or null if not initialized
+ */
+function getDatabase() {
+  return db;
+}
+
+/**
+ * Close database connection
+ */
+function closeDatabase() {
+  if (db) {
+    try {
+      db.close();
+      console.log('✅ Database connection closed');
+    } catch (error) {
+      console.error('Error closing database:', error);
+    } finally {
+      db = null;
+      dbPath = null;
+    }
+  }
+}
+
+/**
+ * Check if database is initialized
+ * @returns {boolean}
+ */
+function isDatabaseInitialized() {
+  return db !== null && db.open;
+}
+
+/**
+ * Get database path
+ * @returns {string|null}
+ */
+function getDatabasePath() {
+  return dbPath;
+}
+
+/**
+ * Create a backup of the database
+ * @param {string} backupPath - Path to backup file
+ * @returns {Promise<void>}
+ */
+async function backupDatabase(backupPath) {
+  if (!db) {
+    throw new Error('Database not initialized');
+  }
+
+  return new Promise((resolve, reject) => {
+    try {
+      const backup = db.backup(backupPath);
+      backup.step(-1); // Copy all pages at once
+      backup.finish();
+      console.log('✅ Database backup created:', backupPath);
+      resolve();
+    } catch (error) {
+      reject(error);
+    }
+  });
+}
+
+/**
+ * Execute a transaction
+ * @param {Function} fn - Function to execute in transaction
+ * @returns {*} Result of the function
+ */
+function transaction(fn) {
+  if (!db) {
+    throw new Error('Database not initialized');
+  }
+  return db.transaction(fn)();
+}
+
+module.exports = {
+  initDatabase,
+  getDatabase,
+  closeDatabase,
+  isDatabaseInitialized,
+  getDatabasePath,
+  backupDatabase,
+  transaction
+};