Merge branch 'develop' into rewrite-swiftui

readium · Sep 19, 2024 · a579cb5 · a579cb5
2 parents 7c53197 + 0cfb105
commit a579cb5
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,7 +4,14 @@ All notable changes to this project will be documented in this file. Take a look
 
 **Warning:** Features marked as *alpha* may change or be removed in a future release without notice. Use with caution.
 
-<!-- ## [Unreleased] -->
+## [Unreleased]
+
+### Fixed
+
+#### Navigator
+
+* [#459](https://github.com/readium/swift-toolkit/issues/459) Fixed the stack overflow issue that occurred when running the text-to-speech on an EPUB file with many empty resources.
+
 
 ## [3.0.0-alpha.2]
 

diff --git a/Sources/Navigator/TTS/PublicationSpeechSynthesizer.swift b/Sources/Navigator/TTS/PublicationSpeechSynthesizer.swift
@@ -339,15 +339,14 @@ public class PublicationSpeechSynthesizer: Loggable {
     /// Loads the utterances for the next publication `ContentElement` item in the given `direction`.
     private func loadNextUtterances(_ direction: Direction) async -> Bool {
         do {
-            guard let content = try await publicationIterator?.next(direction) else {
-                return false
-            }
-
-            let nextUtterances = try tokenize(content)
-                .flatMap { utterances(for: $0) }
+            var nextUtterances: [Utterance] = []
+            while nextUtterances.isEmpty {
+                guard let content = try await publicationIterator?.next(direction) else {
+                    return false
+                }
 
-            if nextUtterances.isEmpty {
-                return await loadNextUtterances(direction)
+                nextUtterances = try tokenize(content)
+                    .flatMap { utterances(for: $0) }
             }
 
             utterances = CursorList(

diff --git a/Sources/Shared/Publication/Services/Search/StringSearchService.swift b/Sources/Shared/Publication/Services/Search/StringSearchService.swift
@@ -102,37 +102,37 @@ public class StringSearchService: SearchService {
         private var index = -1
 
         func next() async -> SearchResult<LocatorCollection?> {
-            guard index < publication.readingOrder.count - 1 else {
-                return .success(nil)
-            }
+            while index < publication.readingOrder.count - 1 {
+                index += 1
+
+                let link = publication.readingOrder[index]
+
+                guard
+                    let resource = publication.get(link),
+                    let mediaType = link.mediaType,
+                    let extractor = extractorFactory.makeExtractor(for: resource, mediaType: mediaType)
+                else {
+                    log(.warning, "Cannot extract text from resource: \(link.href)")
+                    continue
+                }
 
-            index += 1
+                switch await extractor.extractText(of: resource) {
+                case let .success(text):
+                    let locators = await findLocators(in: link, resourceIndex: index, text: text)
+                    // If no occurrences were found in the current resource, skip to the next one automatically.
+                    guard !locators.isEmpty else {
+                        continue
+                    }
 
-            let link = publication.readingOrder[index]
+                    resultCount = (resultCount ?? 0) + locators.count
+                    return .success(LocatorCollection(locators: locators))
 
-            guard
-                let resource = publication.get(link),
-                let mediaType = link.mediaType,
-                let extractor = extractorFactory.makeExtractor(for: resource, mediaType: mediaType)
-            else {
-                log(.warning, "Cannot extract text from resource: \(link.href)")
-                return await next()
-            }
-
-            switch await extractor.extractText(of: resource) {
-            case let .success(text):
-                let locators = await findLocators(in: link, resourceIndex: index, text: text)
-                // If no occurrences were found in the current resource, skip to the next one automatically.
-                guard !locators.isEmpty else {
-                    return await next()
+                case let .failure(error):
+                    return .failure(.reading(error))
                 }
-
-                resultCount = (resultCount ?? 0) + locators.count
-                return .success(LocatorCollection(locators: locators))
-
-            case let .failure(error):
-                return .failure(.reading(error))
             }
+
+            return .success(nil)
         }
 
         private func findLocators(in link: Link, resourceIndex: Int, text: String) async -> [Locator] {