Method UpdateChunkStatus

internal/engine/types/progress.go:434–518

UpdateChunkStatus updates the bitmap based on byte range

(offset, length int64, status ChunkStatus)

// UpdateChunkStatus updates the bitmap based on byte range
func (ps *ProgressState) UpdateChunkStatus(offset, length int64, status ChunkStatus) {
	ps.mu.Lock()

	if ps.ActualChunkSize == 0 || len(ps.ChunkBitmap) == 0 {
		utils.Debug("UpdateChunkStatus skipped: ActualChunkSize=%d, BitmapLen=%d", ps.ActualChunkSize, len(ps.ChunkBitmap))
		ps.mu.Unlock()
		return
	}

	if len(ps.ChunkProgress) != ps.BitmapWidth {
		utils.Debug("UpdateChunkStatus: Initializing ChunkProgress array (width=%d)", ps.BitmapWidth)
		ps.ChunkProgress = make([]int64, ps.BitmapWidth)
	}

	startIdx := int(offset / ps.ActualChunkSize)
	endIdx := int((offset + length - 1) / ps.ActualChunkSize)

	if startIdx < 0 {
		startIdx = 0
	}
	if endIdx >= ps.BitmapWidth {
		endIdx = ps.BitmapWidth - 1
	}

	var totalIncrement int64

	for i := startIdx; i <= endIdx; i++ {
		// Calculate precise overlap with this chunk
		chunkStart := int64(i) * ps.ActualChunkSize
		chunkEnd := chunkStart + ps.ActualChunkSize
		if chunkEnd > ps.TotalSize {
			chunkEnd = ps.TotalSize
		}

		updateStart := offset
		if updateStart < chunkStart {
			updateStart = chunkStart
		}

		updateEnd := offset + length
		if updateEnd > chunkEnd {
			updateEnd = chunkEnd
		}

		overlap := updateEnd - updateStart
		if overlap < 0 {
			overlap = 0
		}

		switch status {
		case ChunkCompleted:
			increment := overlap
			remainingSpace := (chunkEnd - chunkStart) - ps.ChunkProgress[i]

			if increment > remainingSpace {
				increment = remainingSpace
			}