fix: use strftime for millisecond timestamp precision in SQLite

src/db.ts

@@ -15,11 +15,12 @@ export function initializeDatabase(instance: Database) {
   instance.exec(`PRAGMA foreign_keys = ON;`);
 
   // Create users table first as others depend on it
+  // Use TEXT for timestamps to store higher precision ISO8601 format easily
   instance.exec(`
     CREATE TABLE IF NOT EXISTS users (
       id TEXT PRIMARY KEY, -- WhatsApp user ID (normalized)
-      first_seen TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
-      last_seen TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+      first_seen TEXT DEFAULT (strftime('%Y-%m-%d %H:%M:%f', 'now')),
+      last_seen TEXT DEFAULT (strftime('%Y-%m-%d %H:%M:%f', 'now'))
     );
   `);
 
@@ -29,7 +30,7 @@ export function initializeDatabase(instance: Database) {
       id TEXT PRIMARY KEY, -- Group ID (normalized)
       community_id TEXT NOT NULL,
       name TEXT,
-      last_verified TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+      last_verified TEXT DEFAULT (strftime('%Y-%m-%d %H:%M:%f', 'now')),
       active BOOLEAN DEFAULT TRUE
     );
   `);
@@ -39,10 +40,10 @@ export function initializeDatabase(instance: Database) {
     CREATE TABLE IF NOT EXISTS tasks (
       id INTEGER PRIMARY KEY AUTOINCREMENT,
       description TEXT NOT NULL,
-      created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
-      due_date TIMESTAMP NULL,
+      created_at TEXT DEFAULT (strftime('%Y-%m-%d %H:%M:%f', 'now')),
+      due_date TEXT NULL, -- Store dates as ISO8601 strings or YYYY-MM-DD
       completed BOOLEAN DEFAULT FALSE,
-      completed_at TIMESTAMP NULL,
+      completed_at TEXT NULL,
       group_id TEXT NULL, -- Normalized group ID
       created_by TEXT NOT NULL, -- Normalized user ID
       FOREIGN KEY (created_by) REFERENCES users(id) ON DELETE CASCADE,
@@ -56,7 +57,7 @@ export function initializeDatabase(instance: Database) {
       task_id INTEGER NOT NULL,
       user_id TEXT NOT NULL, -- Normalized user ID
       assigned_by TEXT NOT NULL, -- Normalized user ID
-      assigned_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+      assigned_at TEXT DEFAULT (strftime('%Y-%m-%d %H:%M:%f', 'now')),
       PRIMARY KEY (task_id, user_id),
       FOREIGN KEY (task_id) REFERENCES tasks(id) ON DELETE CASCADE,
       FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
@@ -70,6 +71,7 @@ export function initializeDatabase(instance: Database) {
  * If the user exists, updates their last_seen timestamp.
  * If the user does not exist, creates them.
  * Uses the normalizeWhatsAppId utility.
+ * Stores timestamps with millisecond precision.
  * 
  * @param rawUserId The raw WhatsApp ID (e.g., '12345@s.whatsapp.net').
  * @param instance The database instance to use (defaults to the main db).
@@ -84,25 +86,24 @@ export function ensureUserExists(rawUserId: string | null | undefined, instance:
   }
 
   try {
-    // Use INSERT OR IGNORE to add the user only if they don't exist,
-    // then UPDATE their last_seen timestamp regardless.
-    // This is often more efficient than SELECT followed by INSERT/UPDATE.
+    // Use strftime for millisecond precision timestamps
     const insertStmt = instance.prepare(`
       INSERT INTO users (id, first_seen, last_seen) 
-      VALUES (?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP)
+      VALUES (?, strftime('%Y-%m-%d %H:%M:%f', 'now'), strftime('%Y-%m-%d %H:%M:%f', 'now'))
       ON CONFLICT(id) DO NOTHING;
     `);
     
     const updateStmt = instance.prepare(`
       UPDATE users 
-      SET last_seen = CURRENT_TIMESTAMP 
+      SET last_seen = strftime('%Y-%m-%d %H:%M:%f', 'now')
       WHERE id = ?;
     `);
 
     // Run as transaction for atomicity
     instance.transaction(() => {
       insertStmt.run(normalizedId);
-      updateStmt.run(normalizedId);
+      // Update last_seen even if the user was just inserted or already existed
+      updateStmt.run(normalizedId); 
     })(); // Immediately invoke the transaction
 
     return normalizedId;