course,tasklist,task and completed validation

Signed-off-by: Kenneth Obsequio <k80308392@gmail.com>

services/playback_position.service.js

@@ -0,0 +1,40 @@
+/***********************************************************************************************************************************************************************
+ * File Name: playback_position.service.js
+ * Type of Program: Service
+ * Description: Last-known video/audio playback position per (user, lesson, block) — entirely
+ *              decoupled from CompletionRequirement, tracked for ANY video/audio block regardless
+ *              of whether the lesson has a watch-type completion requirement configured. Powers
+ *              "resume where I left off" only; no anti-cheat/wall-clock validation here since
+ *              there's nothing being gated — see completion_requirements.service.js for that.
+ *
+ *   recordPlaybackPosition — last-write-wins upsert (not a ratcheted max — a deliberate rewind
+ *                             should resume there, not snap back to a prior high-water mark).
+ *   getPlaybackPositions   — { [block_id]: percent } for every block tracked on a lesson.
+ *
+ * Author: Kenneth Obsequio (@lash0000)
+ * Date Created: Jul. 17, 2026
+ ***********************************************************************************************************************************************************************/
+'use strict';
+
+const MediaPlaybackPosition = require('../models/courses/media_playback_position.mdl');
+
+async function recordPlaybackPosition(userId, { lessonId, blockId, percent }) {
+    if (!blockId) return;
+
+    await MediaPlaybackPosition.upsert({
+        user_id:   userId,
+        lesson_id: lessonId,
+        block_id:  blockId,
+        percent:   Math.min(100, Math.max(0, Math.round(percent))),
+    }, { conflictFields: ['user_id', 'lesson_id', 'block_id'] });
+}
+
+async function getPlaybackPositions(userId, lessonId) {
+    const rows = await MediaPlaybackPosition.findAll({
+        where: { user_id: userId, lesson_id: lessonId },
+        attributes: ['block_id', 'percent'],
+    });
+    return Object.fromEntries(rows.map((r) => [r.block_id, r.percent]));
+}
+
+module.exports = { recordPlaybackPosition, getPlaybackPositions };