added first slashcommand and refactored the preview cog as result of breaking changes in slashcommand

jeevesbot/database.py

@@ -0,0 +1,34 @@
+#!/usr/bin/env python3
+
+import sqlite3
+
+def init_db():
+    conn = sqlite3.connect(r"jeevesbot/databases/reminders.db")
+    c = conn.cursor()
+    c.execute('''
+    CREATE TABLE IF NOT EXISTS reminders (
+        id INTEGER PRIMARY KEY,
+        user_id INTEGER,
+        message TEXT,
+        reminder_time TIMESTAMP
+    )
+    ''')
+    conn.commit()
+    conn.close()
+
+def add_reminder(user_id, message, reminder_time):
+    conn = sqlite3.connect(r"jeevesbot/databases/reminders.db")
+    c = conn.cursor()
+    c.execute('INSERT INTO reminders (user_id, message, reminder_time) VALUES (?, ?, ?)', (user_id, message, reminder_time))
+    conn.commit()
+    conn.close()
+
+def get_due_reminders(current_time):
+    conn = sqlite3.connect(r"jeevesbot/databases/reminders.db")
+    c = conn.cursor()
+    c.execute('SELECT id, user_id, message FROM reminders WHERE reminder_time <= ?', (current_time,))
+    reminders = c.fetchall()
+    c.execute('DELETE FROM reminders WHERE reminder_time <= ?', (current_time,))
+    conn.commit()
+    conn.close()
+    return reminders