build(spf): build26 from 45504a2b

dist/dev/media/buffer/back-buffer.js

@@ -0,0 +1,46 @@
+//#region src/media/buffer/back-buffer.ts
+/**
+* Default back buffer configuration.
+*/
+const DEFAULT_BACK_BUFFER_CONFIG = { keepSegments: 2 };
+/**
+* Calculate back buffer flush point.
+*
+* Determines where to flush old segments from the back buffer.
+* Keeps a fixed number of segments behind the current playback position.
+*
+* Algorithm:
+* 1. Find segments before currentTime
+* 2. Count back N segments (keepSegments)
+* 3. Return startTime of segment N+1 back (flush everything before this)
+*
+* @param segments - Available segments (should be sorted by startTime)
+* @param currentTime - Current playback position in seconds
+* @param config - Optional back buffer configuration
+* @returns Time in seconds to flush up to (flush range: [0, flushEnd))
+*
+* @example
+* const segments = [
+*   { startTime: 0, duration: 6, ... },
+*   { startTime: 6, duration: 6, ... },
+*   { startTime: 12, duration: 6, ... },
+*   { startTime: 18, duration: 6, ... },
+* ];
+*
+* // Playing at 18s, keep 2 segments
+* const flushEnd = calculateBackBufferFlushPoint(segments, 18);
+* // Returns 6 (flush [0, 6), keep [6-18))
+*/
+function calculateBackBufferFlushPoint(segments, currentTime, config = DEFAULT_BACK_BUFFER_CONFIG) {
+	if (segments.length === 0) return 0;
+	const segmentsBefore = segments.filter((seg) => seg.startTime < currentTime);
+	if (segmentsBefore.length === 0) return 0;
+	const segmentsToFlush = segmentsBefore.length - config.keepSegments;
+	if (segmentsToFlush <= 0) return 0;
+	if (segmentsToFlush >= segmentsBefore.length) return currentTime;
+	return segmentsBefore[segmentsToFlush].startTime;
+}
+//#endregion
+export { DEFAULT_BACK_BUFFER_CONFIG, calculateBackBufferFlushPoint };
+
+//# sourceMappingURL=back-buffer.js.map