| import CoreMedia |
| import Foundation |
| import NaturalLanguage |
|
|
| extension AttributedString { |
| public func sentences(maxLength: Int? = nil) -> [AttributedString] { |
| let tokenizer = NLTokenizer(unit: .sentence) |
| let string = String(characters) |
| tokenizer.string = string |
| let sentenceRanges = tokenizer.tokens(for: string.startIndex..<string.endIndex).map { |
| ( |
| $0, |
| AttributedString.Index($0.lowerBound, within: self)! |
| ..< |
| AttributedString.Index($0.upperBound, within: self)!) |
| } |
| let ranges = sentenceRanges.flatMap { sentenceStringRange, sentenceRange in |
| let sentence = self[sentenceRange] |
| guard let maxLength, sentence.characters.count > maxLength else { |
| return [sentenceRange] |
| } |
|
|
| let wordTokenizer = NLTokenizer(unit: .word) |
| wordTokenizer.string = string |
| var wordRanges = wordTokenizer.tokens(for: sentenceStringRange).map { |
| AttributedString.Index($0.lowerBound, within: self)! |
| ..< |
| AttributedString.Index($0.upperBound, within: self)! |
| } |
| guard !wordRanges.isEmpty else { return [sentenceRange] } |
| wordRanges[0] = sentenceRange.lowerBound..<wordRanges[0].upperBound |
| wordRanges[wordRanges.count - 1] = wordRanges[wordRanges.count - 1].lowerBound..<sentenceRange.upperBound |
|
|
| var ranges: [Range<AttributedString.Index>] = [] |
| for wordRange in wordRanges { |
| if let lastRange = ranges.last, |
| self[lastRange].characters.count + self[wordRange].characters.count <= maxLength { |
| ranges[ranges.count - 1] = lastRange.lowerBound..<wordRange.upperBound |
| } else { |
| ranges.append(wordRange) |
| } |
| } |
|
|
| return ranges |
| } |
|
|
| return ranges.compactMap { range in |
| let audioTimeRanges = self[range].runs.filter { |
| !String(self[$0.range].characters) |
| .trimmingCharacters(in: .whitespacesAndNewlines).isEmpty |
| }.compactMap(\.audioTimeRange) |
| guard !audioTimeRanges.isEmpty else { return nil } |
| let start = audioTimeRanges.first!.start |
| let end = audioTimeRanges.last!.end |
| var attributes = AttributeContainer() |
| attributes[AttributeScopes.SpeechAttributes.TimeRangeAttribute.self] = CMTimeRange( |
| start: start, |
| end: end) |
| return AttributedString(self[range].characters, attributes: attributes) |
| } |
| } |
| } |
|
|
