Analytics heatmaps and segment engagement #215

Summary

Add detailed analytics showing which parts of videos are watched, skipped, or rewatched.

Current State

Analytics track total views, watch time, and completion rates. No granular segment-level data.

Proposed Features

Engagement Heatmap

• Visual heatmap showing viewer engagement across video timeline
• Identify popular segments (high rewatch)
• Identify drop-off points (where viewers leave)
• Identify skipped sections

Data Collection

• Track segment views (e.g., 10-second buckets)
• Track seek events (skip forward/backward)
• Track pause/resume patterns
• Aggregate data for privacy (no per-user tracking)

Visualization

• Heatmap overlay on video timeline in admin
• Per-video engagement report
• Comparative analysis across videos

Database Schema

CREATE TABLE segment_analytics (
  video_id TEXT REFERENCES videos(id),
  segment_start REAL,  -- seconds
  segment_end REAL,
  view_count INTEGER DEFAULT 0,
  rewatch_count INTEGER DEFAULT 0,
  skip_count INTEGER DEFAULT 0,
  updated_at TIMESTAMP,
  PRIMARY KEY (video_id, segment_start)
);

API Endpoints

GET /admin/videos/{id}/heatmap
POST /api/analytics/segment  # Record segment view (batched)

Client-Side Integration

• Batch segment tracking to reduce API calls
• 10-second segment granularity
• Send on pause, seek, and periodically

Use Cases

• Content creators: Understand what content resonates
• Educators: Identify confusing sections needing revision
• Marketers: Optimize video length and pacing

Priority

Lower - advanced analytics feature