PrismatIQ::ThemeDetector

Thread-safe theme detector with instance-based caching.

This class detects whether a color scheme is light or dark based on relative luminance calculations. Results are cached for performance.

Thread Safety Guarantees

• Instance Isolation: Each ThemeDetector instance has its own cache. Multiple threads can safely use different instances without coordination.
• Internal Synchronization: Caches use ThreadSafeCache with mutex synchronization.
• No Global State: No class variables or shared mutable state between instances.
• Safe Concurrent Access: Multiple fibers/threads can call methods on the same instance simultaneously without race conditions.

Usage Patterns

Create instances as needed - they can be safely shared across threads:

# Safe to share across multiple fibers
detector = ThemeDetector.new
spawn { detector.detect_theme(color1) }
spawn { detector.detect_theme(color2) }

Migration Note

This replaces the deprecated module-level PrismatIQ::Theme methods which were not thread-safe due to shared global state.

• Each instance has its own cache (no shared global state)
• Safe to share a single instance across fibers, or create per-fiber instances
• Caching uses ThreadSafeCache with mutex synchronization

Example

detector = ThemeDetector.new

# These calls are thread-safe
theme = detector.detect_theme(color)
info = detector.detect_theme_info(color)

# Clear cache when done (also thread-safe)
detector.clear_cache