28 lines
735 B
TypeScript
28 lines
735 B
TypeScript
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import batch from 'it-batch'
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import type { FileLayout } from './index.js'
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import type { InProgressImportResult } from '../index.js'
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const DEFAULT_MAX_CHILDREN_PER_NODE = 174
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export interface BalancedOptions {
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maxChildrenPerNode?: number
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}
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export function balanced (options?: BalancedOptions): FileLayout {
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const maxChildrenPerNode = options?.maxChildrenPerNode ?? DEFAULT_MAX_CHILDREN_PER_NODE
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return async function balancedLayout (source, reduce): Promise<InProgressImportResult> {
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const roots = []
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for await (const chunked of batch(source, maxChildrenPerNode)) {
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roots.push(await reduce(chunked))
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}
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if (roots.length > 1) {
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return balancedLayout(roots, reduce)
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}
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return roots[0]
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}
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}
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