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chrome-devtools-frontend

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// Copyright 2016 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. import * as Platform from '../platform/platform.js'; export class Segment<T> { begin: number; end: number; data: T; constructor(begin: number, end: number, data: T) { if (begin > end) { throw new Error('Invalid segment'); } this.begin = begin; this.end = end; this.data = data; } intersects(that: Segment<T>): boolean { return this.begin < that.end && that.begin < this.end; } } export class SegmentedRange<T> { #segmentsInternal: Segment<T>[]; readonly #mergeCallback: ((arg0: Segment<T>, arg1: Segment<T>) => Segment<T>| null)|undefined; constructor(mergeCallback?: ((arg0: Segment<T>, arg1: Segment<T>) => Segment<T>| null)) { this.#segmentsInternal = []; this.#mergeCallback = mergeCallback; } append(newSegment: Segment<T>): void { // 1. Find the proper insertion point for new segment let startIndex = Platform.ArrayUtilities.lowerBound(this.#segmentsInternal, newSegment, (a, b) => a.begin - b.begin); let endIndex = startIndex; let merged: (Segment<T>|null)|null = null; if (startIndex > 0) { // 2. Try mering the preceding segment const precedingSegment = this.#segmentsInternal[startIndex - 1]; merged = this.tryMerge(precedingSegment, newSegment); if (merged) { --startIndex; newSegment = merged; } else if (this.#segmentsInternal[startIndex - 1].end >= newSegment.begin) { // 2a. If merge failed and segments overlap, adjust preceding segment. // If an old segment entirely contains new one, split it in two. if (newSegment.end < precedingSegment.end) { this.#segmentsInternal.splice( startIndex, 0, new Segment<T>(newSegment.end, precedingSegment.end, precedingSegment.data)); } precedingSegment.end = newSegment.begin; } } // 3. Consume all segments that are entirely covered by the new one. while (endIndex < this.#segmentsInternal.length && this.#segmentsInternal[endIndex].end <= newSegment.end) { ++endIndex; } // 4. Merge or adjust the succeeding segment if it overlaps. if (endIndex < this.#segmentsInternal.length) { merged = this.tryMerge(newSegment, this.#segmentsInternal[endIndex]); if (merged) { endIndex++; newSegment = merged; } else if (newSegment.intersects(this.#segmentsInternal[endIndex])) { this.#segmentsInternal[endIndex].begin = newSegment.end; } } this.#segmentsInternal.splice(startIndex, endIndex - startIndex, newSegment); } appendRange(that: SegmentedRange<T>): void { that.segments().forEach(segment => this.append(segment)); } segments(): Segment<T>[] { return this.#segmentsInternal; } private tryMerge(first: Segment<T>, second: Segment<T>): Segment<T>|null { const merged = this.#mergeCallback && this.#mergeCallback(first, second); if (!merged) { return null; } merged.begin = first.begin; merged.end = Math.max(first.end, second.end); return merged; } }