diff --git a/Dreamio/StreamResolver.swift b/Dreamio/StreamResolver.swift index 55e790e..1ee8cbc 100644 --- a/Dreamio/StreamResolver.swift +++ b/Dreamio/StreamResolver.swift @@ -97,7 +97,7 @@ final class SubtitleResolver: SubtitleResolving { } private func cacheSubtitleDataIfNeeded(_ data: Data, original: SubtitleCandidate) -> SubtitleCandidate? { - guard let subtitleType = Self.subtitleType(in: data) else { + guard let subtitleType = Self.subtitleType(in: data, sourceURL: original.url) else { return nil } @@ -204,7 +204,7 @@ final class SubtitleResolver: SubtitleResolving { } } - private static func subtitleType(in data: Data) -> SubtitlePayloadType? { + private static func subtitleType(in data: Data, sourceURL: URL? = nil) -> SubtitlePayloadType? { guard !data.isEmpty, let text = String(data: data.prefix(4096), encoding: .utf8)? .trimmingCharacters(in: .whitespacesAndNewlines), @@ -228,9 +228,32 @@ final class SubtitleResolver: SubtitleResolving { ) != nil { return .srt } + if let sourceURL, + isStremioSubtitleDownloadURL(sourceURL), + isPlausiblePlainSubtitleText(text) { + return .srt + } return nil } + private static func isPlausiblePlainSubtitleText(_ text: String) -> Bool { + let lowercased = text.lowercased() + guard !lowercased.hasPrefix("{"), + !lowercased.hasPrefix("["), + !lowercased.hasPrefix("") + || lowercased.contains(" 1 + } + private static func logRejected(_ candidate: SubtitleCandidate, responseURL: URL?, data: Data) -> SubtitleCandidate? { #if DEBUG let responseDescription = responseURL.map { URLRedactor.redactedURLString($0.absoluteString) } ?? "none" @@ -244,10 +267,21 @@ final class SubtitleResolver: SubtitleResolving { } else { bodyKind = "unreadable" } - print("[DreamioSubtitles] rejected candidate reason=\(bodyKind) url=\(URLRedactor.redactedURLString(candidate.url.absoluteString)) responseURL=\(responseDescription)") + print("[DreamioSubtitles] rejected candidate reason=\(bodyKind) url=\(URLRedactor.redactedURLString(candidate.url.absoluteString)) responseURL=\(responseDescription) preview=\(rejectionPreview(data))") #endif return nil } + +#if DEBUG + private static func rejectionPreview(_ data: Data) -> String { + guard let text = String(data: data.prefix(180), encoding: .utf8) else { + return "unreadable" + } + return text + .replacingOccurrences(of: "\n", with: "\\n") + .replacingOccurrences(of: "\r", with: "\\r") + } +#endif } protocol StreamResolving { diff --git a/Tests/StreamResolverTests.swift b/Tests/StreamResolverTests.swift index a513abb..09986e0 100644 --- a/Tests/StreamResolverTests.swift +++ b/Tests/StreamResolverTests.swift @@ -17,6 +17,7 @@ struct StreamResolverTests { testOpenSubtitlesV3DownloadResponseResolution() testOpenSubtitlesNestedDownloadResponseResolution() await testSubtitleResolverCachesStremioDownloadBody() + await testSubtitleResolverCachesPlainStremioDownloadBody() await testSubtitleResolverDownloadJSONReturningLink() await testSubtitleResolverRedirectToDirectSubtitle() await testSubtitleResolverRejectsNonSubtitleAPIResponse() @@ -476,6 +477,41 @@ struct StreamResolverTests { assertEqual(cachedBody, subtitleBody) } + private static func testSubtitleResolverCachesPlainStremioDownloadBody() async { + let sourceURL = "https://subs5.strem.io/en/download/subencoding-stremio-utf8/src-api/file/1952341942" + let subtitleBody = """ + 00:01.000 --> 00:02.000 + Plain cue text without an index + + """ + MockURLProtocol.handler = nil + MockURLProtocol.handlers = [ + sourceURL: ( + 200, + URL(string: sourceURL)!, + subtitleBody.data(using: .utf8)! + ) + ] + + let cacheDirectory = FileManager.default.temporaryDirectory + .appendingPathComponent("DreamioSubtitleResolverTests-\(UUID().uuidString)", isDirectory: true) + defer { + try? FileManager.default.removeItem(at: cacheDirectory) + } + + let resolver = SubtitleResolver(session: mockSession(), cacheDirectory: cacheDirectory) + let candidate = await resolver.resolve(SubtitleCandidate( + url: URL(string: sourceURL)!, + label: "English", + language: "eng" + )) + + assertEqual(candidate?.url.isFileURL, true) + assertEqual(candidate?.url.pathExtension, "srt") + let cachedBody = try? String(contentsOf: candidate!.url, encoding: .utf8) + assertEqual(cachedBody, subtitleBody) + } + private static func testSubtitleResolverDownloadJSONReturningLink() async { MockURLProtocol.handler = nil MockURLProtocol.handlers = [ diff --git a/docs/turns/2026-05-25-queue-vlc-subtitles-until-media-start.html b/docs/turns/2026-05-25-queue-vlc-subtitles-until-media-start.html index 9d94d10..9132542 100644 --- a/docs/turns/2026-05-25-queue-vlc-subtitles-until-media-start.html +++ b/docs/turns/2026-05-25-queue-vlc-subtitles-until-media-start.html @@ -346,9 +346,166 @@

Related Beads issue: dreamio-771.

+ +
+

New Changes as of May 25, 2026 at 7:00 PM EDT

+

Summary of changes

+

Device logs showed Stremio subtitle downloads returning text, but the strict resolver detector rejected every body as text-without-direct-subtitle. The resolver now accepts plausible plain subtitle text from Stremio download endpoints and caches it as a local .srt file.

+

Why this change was made

+

The previous cache step only recognized classic indexed SRT, WebVTT, and ASS signatures. The live Stremio payloads appear to be subtitle-like text without matching that narrow signature, so they never reached VLC. This update keeps strict handling for general URLs while applying a provider-specific fallback for Stremio subtitle downloads.

+

Code diffs

+
Dreamio/StreamResolver.swift
-3+37
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    }

+
    private func cacheSubtitleDataIfNeeded(_ data: Data, original: SubtitleCandidate) -> SubtitleCandidate? {
        guard let subtitleType = Self.subtitleType(in: data) else {
            return nil
        }

+
100 unmodified lines
        }
    }

+
    private static func subtitleType(in data: Data) -> SubtitlePayloadType? {
        guard !data.isEmpty,
              let text = String(data: data.prefix(4096), encoding: .utf8)?
                .trimmingCharacters(in: .whitespacesAndNewlines),
17 unmodified lines
        ) != nil {
            return .srt
        }
        return nil
    }

+
    private static func logRejected(_ candidate: SubtitleCandidate, responseURL: URL?, data: Data) -> SubtitleCandidate? {
#if DEBUG
        let responseDescription = responseURL.map { URLRedactor.redactedURLString($0.absoluteString) } ?? "none"
7 unmodified lines
        } else {
            bodyKind = "unreadable"
        }
        print("[DreamioSubtitles] rejected candidate reason=\(bodyKind) url=\(URLRedactor.redactedURLString(candidate.url.absoluteString)) responseURL=\(responseDescription)")
#endif
        return nil
    }
}

+
protocol StreamResolving {
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    }

+
    private func cacheSubtitleDataIfNeeded(_ data: Data, original: SubtitleCandidate) -> SubtitleCandidate? {
        guard let subtitleType = Self.subtitleType(in: data, sourceURL: original.url) else {
            return nil
        }

+
100 unmodified lines
        }
    }

+
    private static func subtitleType(in data: Data, sourceURL: URL? = nil) -> SubtitlePayloadType? {
        guard !data.isEmpty,
              let text = String(data: data.prefix(4096), encoding: .utf8)?
                .trimmingCharacters(in: .whitespacesAndNewlines),
17 unmodified lines
        ) != nil {
            return .srt
        }
        if let sourceURL,
           isStremioSubtitleDownloadURL(sourceURL),
           isPlausiblePlainSubtitleText(text) {
            return .srt
        }
        return nil
    }

+
    private static func isPlausiblePlainSubtitleText(_ text: String) -> Bool {
        let lowercased = text.lowercased()
        guard !lowercased.hasPrefix("{"),
              !lowercased.hasPrefix("["),
              !lowercased.hasPrefix("<!doctype"),
              !lowercased.hasPrefix("<html"),
              !lowercased.hasPrefix("<?xml")
        else {
            return false
        }

+
        return lowercased.contains("-->")
            || lowercased.contains("<font")
            || lowercased.contains("{\\")
            || lowercased.contains("\\n")
            || lowercased.split(whereSeparator: \.isNewline).count > 1
    }

+
    private static func logRejected(_ candidate: SubtitleCandidate, responseURL: URL?, data: Data) -> SubtitleCandidate? {
#if DEBUG
        let responseDescription = responseURL.map { URLRedactor.redactedURLString($0.absoluteString) } ?? "none"
7 unmodified lines
        } else {
            bodyKind = "unreadable"
        }
        print("[DreamioSubtitles] rejected candidate reason=\(bodyKind) url=\(URLRedactor.redactedURLString(candidate.url.absoluteString)) responseURL=\(responseDescription) preview=\(rejectionPreview(data))")
#endif
        return nil
    }

+
#if DEBUG
    private static func rejectionPreview(_ data: Data) -> String {
        guard let text = String(data: data.prefix(180), encoding: .utf8) else {
            return "unreadable"
        }
        return text
            .replacingOccurrences(of: "\n", with: "\\n")
            .replacingOccurrences(of: "\r", with: "\\r")
    }
#endif
}

+
protocol StreamResolving {
Tests/StreamResolverTests.swift
+36
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        testOpenSubtitlesV3DownloadResponseResolution()
        testOpenSubtitlesNestedDownloadResponseResolution()
        await testSubtitleResolverCachesStremioDownloadBody()
        await testSubtitleResolverDownloadJSONReturningLink()
        await testSubtitleResolverRedirectToDirectSubtitle()
        await testSubtitleResolverRejectsNonSubtitleAPIResponse()
453 unmodified lines
        assertEqual(cachedBody, subtitleBody)
    }

+
    private static func testSubtitleResolverDownloadJSONReturningLink() async {
        MockURLProtocol.handler = nil
        MockURLProtocol.handlers = [
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        testOpenSubtitlesV3DownloadResponseResolution()
        testOpenSubtitlesNestedDownloadResponseResolution()
        await testSubtitleResolverCachesStremioDownloadBody()
        await testSubtitleResolverCachesPlainStremioDownloadBody()
        await testSubtitleResolverDownloadJSONReturningLink()
        await testSubtitleResolverRedirectToDirectSubtitle()
        await testSubtitleResolverRejectsNonSubtitleAPIResponse()
453 unmodified lines
        assertEqual(cachedBody, subtitleBody)
    }

+
    private static func testSubtitleResolverCachesPlainStremioDownloadBody() async {
        let sourceURL = "https://subs5.strem.io/en/download/subencoding-stremio-utf8/src-api/file/1952341942"
        let subtitleBody = """
        00:01.000 --> 00:02.000
        Plain cue text without an index

+
        """
        MockURLProtocol.handler = nil
        MockURLProtocol.handlers = [
            sourceURL: (
                200,
                URL(string: sourceURL)!,
                subtitleBody.data(using: .utf8)!
            )
        ]

+
        let cacheDirectory = FileManager.default.temporaryDirectory
            .appendingPathComponent("DreamioSubtitleResolverTests-\(UUID().uuidString)", isDirectory: true)
        defer {
            try? FileManager.default.removeItem(at: cacheDirectory)
        }

+
        let resolver = SubtitleResolver(session: mockSession(), cacheDirectory: cacheDirectory)
        let candidate = await resolver.resolve(SubtitleCandidate(
            url: URL(string: sourceURL)!,
            label: "English",
            language: "eng"
        ))

+
        assertEqual(candidate?.url.isFileURL, true)
        assertEqual(candidate?.url.pathExtension, "srt")
        let cachedBody = try? String(contentsOf: candidate!.url, encoding: .utf8)
        assertEqual(cachedBody, subtitleBody)
    }

+
    private static func testSubtitleResolverDownloadJSONReturningLink() async {
        MockURLProtocol.handler = nil
        MockURLProtocol.handlers = [
+

Related issues or PRs

+

Related Beads issue: dreamio-8oe.

+
+

Expected Impact for End-Users

-

When an MKV stream opens through the real local range buffer, subtitles discovered before playback should still appear in the captions menu and be eligible for auto-selection once VLC exposes the track list. Stremio subtitle downloads should now reach VLC as local subtitle files rather than extensionless provider URLs.

+

When an MKV stream opens through the real local range buffer, subtitles discovered before playback should still appear in the captions menu and be eligible for auto-selection once VLC exposes the track list. Stremio subtitle downloads should now reach VLC as local subtitle files rather than extensionless provider URLs, including plain cue-text payloads that do not match classic indexed SRT.

@@ -357,21 +514,21 @@
  • Ran git diff --check: passed.
  • Ran pod install to restore missing local CocoaPods support files in this worktree.
  • Ran xcodebuild -workspace Dreamio.xcworkspace -scheme Dreamio -destination 'generic/platform=iOS Simulator' -quiet build: passed.
    • -
  • Ran swiftc -parse-as-library -D DEBUG Dreamio/StreamCandidate.swift Dreamio/StreamResolver.swift Dreamio/ProgressiveHTTPRangeCache.swift Tests/StreamResolverTests.swift -o /tmp/StreamResolverTests && /tmp/StreamResolverTests: passed, including the new Stremio subtitle cache test.
    • +
  • Ran swiftc -parse-as-library -D DEBUG Dreamio/StreamCandidate.swift Dreamio/StreamResolver.swift Dreamio/ProgressiveHTTPRangeCache.swift Tests/StreamResolverTests.swift -o /tmp/StreamResolverTests && /tmp/StreamResolverTests: passed, including the Stremio subtitle cache tests for strict SRT and plain cue text.
  • The build still reports existing MobileVLCKit warnings about simulator deployment target and a run-script phase, but compilation succeeded.

    • Issues, Limitations, and Mitigations

    -

    This addresses the pre-media attachment race shown in the logs and the follow-on issue where extensionless Stremio subtitle download URLs were accepted by VLC without visible tracks. If a provider returns a compressed archive, a non-UTF-8 payload, or a format outside SRT, VTT, ASS, SSA, and SUB, that would still need a separate resolver enhancement.

    +

    This addresses the pre-media attachment race shown in the logs and the follow-on issue where extensionless Stremio subtitle download URLs were accepted by VLC without visible tracks. If a provider returns a compressed archive, a non-UTF-8 payload, HTML/XML, JSON without a direct subtitle link, or a format VLC cannot parse after local caching, that would still need a separate resolver enhancement.

    Follow-up Work