feat(ios): improve share preview (#15538)

#### PR Dependency Tree

* **PR #15538** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Added rich link previews to mobile and iOS sharing, including images,
metadata, transcripts, and selected text.
* Share imports can now create structured content blocks, embeds,
bookmarks, and transcript callouts.
* Added workspace-aware preview handling for cloud, self-hosted, and
signed-out modes.
* **Accessibility**
* Improved collapse/expand controls with semantic buttons and ARIA
relationships.
* **Bug Fixes**
  * Enhanced URL and error sanitization in server logs.
* Improved link-preview CORS support, validation, and request handling.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/apps/ios/App/Shared/ShareInbox/ShareInboxConstants.swift

@@ -10,5 +10,9 @@ enum ShareInboxConstants {
   static let inboxDirectoryName = "ShareInbox"
   static let attachmentsDirectoryName = "Attachments"
   static let invalidDirectoryName = "Invalid"
+  static let workspaceModeFileName = "ShareWorkspaceMode.json"
+  static let officialLinkPreviewURL = URL(
+    string: "https://app.affine.pro/api/worker/link-preview"
+  )!
   static let openInboxURL = URL(string: "affine://share-inbox")!
 }

packages/frontend/apps/ios/App/Shared/ShareInbox/ShareInboxModels.swift

@@ -36,6 +36,7 @@ struct ShareInboxItem: Codable, Equatable, Identifiable {
   var createdAt: Date
   var title: String
   var content: ShareInboxContent
+  var previewRoute: SharePreviewRoute?
   var target: ShareInboxTarget?
   var previewText: String?
   var attachments: [ShareInboxAttachment]
@@ -48,6 +49,7 @@ struct ShareInboxItem: Codable, Equatable, Identifiable {
     createdAt: Date = Date(),
     title: String,
     content: ShareInboxContent,
+    previewRoute: SharePreviewRoute? = nil,
     target: ShareInboxTarget? = nil,
     previewText: String? = nil,
     attachments: [ShareInboxAttachment] = [],
@@ -59,6 +61,7 @@ struct ShareInboxItem: Codable, Equatable, Identifiable {
     self.createdAt = createdAt
     self.title = title
     self.content = content
+    self.previewRoute = previewRoute
     self.target = target
     self.previewText = previewText
     self.attachments = attachments

packages/frontend/apps/ios/App/Shared/ShareInbox/ShareInboxSafety.swift

@@ -1,6 +1,44 @@
 import Foundation
 
+enum ShareWorkspaceMode: String, Codable {
+  case selfHostedPresent
+  case cloudOnly
+  case signedOut
+  case unknown
+}
+
+enum SharePreviewRoute: String, Codable {
+  case official
+  case deferred
+}
+
+struct ShareWorkspaceModeSnapshot: Codable, Equatable {
+  static let schemaVersion = 1
+
+  var mode: ShareWorkspaceMode
+  var schemaVersion: Int
+  var updatedAt: Date
+
+  init(mode: ShareWorkspaceMode, updatedAt: Date = Date()) {
+    self.mode = mode
+    self.schemaVersion = Self.schemaVersion
+    self.updatedAt = updatedAt
+  }
+}
+
 enum ShareInboxSafety {
+  private static let workspaceModeMaxAge: TimeInterval = 24 * 60 * 60
+
+  static func manifestTitle(original: String, userEdited: String?) -> String {
+    (userEdited ?? original).trimmingCharacters(in: .whitespacesAndNewlines)
+  }
+
+  static func previewTitle(original: String, userEdited: String?, serverTitle: String?) -> String {
+    if let userEdited { return userEdited }
+    guard let serverTitle, !serverTitle.isEmpty else { return original }
+    return serverTitle
+  }
+
   static func normalizedManifestID(_ value: String) -> String? {
     UUID(uuidString: value)?.uuidString
   }
@@ -22,6 +60,56 @@ enum ShareInboxSafety {
     return url.absoluteString
   }
 
+  static func isOfficialPreviewURL(_ value: String) -> Bool {
+    guard let normalized = normalizedWebURL(value), let url = URL(string: normalized) else {
+      return false
+    }
+    let host = url.host?.lowercased()
+    let components = url.pathComponents.filter { $0 != "/" }
+    if ["x.com", "www.x.com", "twitter.com", "www.twitter.com"].contains(host) {
+      return components.count == 3
+        && components[1] == "status"
+        && !components[2].isEmpty
+        && components[2].allSatisfy(\.isNumber)
+    }
+    if host == "youtu.be" {
+      return components.count == 1 && !components[0].isEmpty
+    }
+    if ["youtube.com", "www.youtube.com", "m.youtube.com"].contains(host) {
+      if url.path == "/watch" {
+        return !(URLComponents(url: url, resolvingAgainstBaseURL: false)?
+          .queryItems?.first(where: { $0.name == "v" })?.value?.isEmpty ?? true)
+      }
+      return components.count == 2
+        && ["shorts", "live", "embed"].contains(components[0])
+        && !components[1].isEmpty
+    }
+    return false
+  }
+
+  static func previewRoute(mode: ShareWorkspaceMode, url: String) -> SharePreviewRoute {
+    if isOfficialPreviewURL(url) { return .official }
+    switch mode {
+    case .cloudOnly, .signedOut:
+      return .official
+    case .selfHostedPresent, .unknown:
+      return .deferred
+    }
+  }
+
+  static func workspaceMode(from data: Data?, now: Date = Date()) -> ShareWorkspaceMode {
+    guard let data else { return .unknown }
+    let decoder = JSONDecoder()
+    decoder.dateDecodingStrategy = .iso8601
+    guard let snapshot = try? decoder.decode(ShareWorkspaceModeSnapshot.self, from: data),
+          snapshot.schemaVersion == ShareWorkspaceModeSnapshot.schemaVersion,
+          (0...workspaceModeMaxAge).contains(now.timeIntervalSince(snapshot.updatedAt))
+    else {
+      return .unknown
+    }
+    return snapshot.mode
+  }
+
   static func detectRasterImageMimeType(_ data: Data) -> String? {
     let bytes = [UInt8](data.prefix(12))
     if bytes.starts(with: [0xFF, 0xD8, 0xFF]) {

packages/frontend/apps/ios/App/Shared/ShareInbox/ShareInboxStore.swift

@@ -102,6 +102,21 @@ final class ShareInboxStore {
     try encoder.encode(item).write(to: fileURL, options: .atomic)
   }
 
+  func updateWorkspaceMode(_ mode: ShareWorkspaceMode) throws {
+    guard let containerURL else { throw ShareInboxError.containerUnavailable }
+    let url = containerURL.appendingPathComponent(ShareInboxConstants.workspaceModeFileName)
+    try encoder.encode(ShareWorkspaceModeSnapshot(mode: mode)).write(to: url, options: .atomic)
+  }
+
+  func workspaceMode() -> ShareWorkspaceMode {
+    guard let containerURL,
+          let data = try? Data(
+            contentsOf: containerURL.appendingPathComponent(ShareInboxConstants.workspaceModeFileName)
+          )
+    else { return .unknown }
+    return ShareInboxSafety.workspaceMode(from: data)
+  }
+
   func pendingItems() -> [ShareInboxItem] {
     guard ensureDirectories(), let inboxDirectoryURL else { return [] }
     guard let urls = try? fileManager.contentsOfDirectory(

packages/frontend/apps/ios/App/Shared/ShareInbox/ShareLinkPreview.swift

@@ -0,0 +1,164 @@
+import Foundation
+import UIKit
+
+struct ShareLinkPreview: Decodable, Equatable {
+  struct Author: Decodable, Equatable {
+    var name: String
+    var handle: String?
+    var avatar: String?
+  }
+
+  struct Transcript: Decodable, Equatable {
+    struct Segment: Decodable, Equatable {
+      var text: String
+      var startSeconds: Double?
+      var durationSeconds: Double?
+      var speaker: String?
+    }
+
+    struct Chapter: Decodable, Equatable {
+      var title: String
+      var startSeconds: Double
+    }
+
+    var language: String?
+    var segments: [Segment]
+    var chapters: [Chapter]?
+    var truncated: Bool?
+  }
+
+  var url: String
+  var title: String?
+  var siteName: String?
+  var description: String?
+  var images: [String]?
+  var favicons: [String]?
+  var mediaType: String?
+  var provider: String?
+  var author: Author?
+  var publishedAt: String?
+  var durationSeconds: Double?
+  var transcript: Transcript?
+}
+
+extension ShareLinkPreview.Transcript {
+  var previewText: String? {
+    let text = segments
+      .map { $0.text.split(whereSeparator: \.isWhitespace).joined(separator: " ") }
+      .filter { !$0.isEmpty }
+      .joined(separator: " ")
+    guard !text.isEmpty else { return nil }
+    guard text.count > 240 else { return text }
+    return String(text.prefix(240)) + "…"
+  }
+}
+
+enum ShareLinkPreviewState: Equatable {
+  case idle
+  case deferred
+  case loading
+  case loaded(ShareLinkPreview)
+  case failed
+}
+
+struct ShareLinkPreviewClient {
+  private let session: URLSession
+  private let appVersion: String
+
+  init(session: URLSession? = nil, appVersion: String? = nil) {
+    self.appVersion = appVersion ?? Self.bundledAppVersion
+    if let session {
+      self.session = session
+    } else {
+      let configuration = URLSessionConfiguration.ephemeral
+      configuration.timeoutIntervalForRequest = 4
+      configuration.timeoutIntervalForResource = 6
+      configuration.requestCachePolicy = .reloadIgnoringLocalCacheData
+      configuration.urlCache = nil
+      self.session = URLSession(configuration: configuration)
+    }
+  }
+
+  func fetch(url: String) async throws -> ShareLinkPreview {
+    guard let normalized = ShareInboxSafety.normalizedWebURL(url) else {
+      throw URLError(.badURL)
+    }
+    var request = URLRequest(url: ShareInboxConstants.officialLinkPreviewURL)
+    request.httpMethod = "POST"
+    request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+    addClientHeaders(to: &request)
+    request.httpBody = try JSONEncoder().encode(
+      Request(url: normalized, include: ["transcript"])
+    )
+    let (data, response) = try await session.data(for: request)
+    guard let response = response as? HTTPURLResponse, response.statusCode == 200 else {
+      throw URLError(.badServerResponse)
+    }
+    return try JSONDecoder().decode(ShareLinkPreview.self, from: data)
+  }
+
+  func fetchImage(url value: String) async throws -> UIImage {
+    guard let candidate = URL(
+      string: value,
+      relativeTo: ShareInboxConstants.officialLinkPreviewURL
+    ) else {
+      throw URLError(.badURL)
+    }
+    let resolved = candidate.absoluteURL
+    guard
+      let normalized = ShareInboxSafety.normalizedWebURL(resolved.absoluteString),
+      let url = URL(string: normalized)
+    else {
+      throw URLError(.badURL)
+    }
+    var request = URLRequest(
+      url: url,
+      cachePolicy: .reloadIgnoringLocalCacheData,
+      timeoutInterval: 3
+    )
+    addClientHeaders(to: &request)
+    let (data, response) = try await session.data(for: request)
+    guard let response = response as? HTTPURLResponse, response.statusCode == 200 else {
+      throw URLError(.badServerResponse)
+    }
+    guard let image = UIImage(data: data) else {
+      throw URLError(.cannotDecodeContentData)
+    }
+    return image
+  }
+
+  func fetchImageIfPresent(url: String?) async -> UIImage? {
+    guard let url else { return nil }
+    return try? await fetchImage(url: url)
+  }
+
+  private func addClientHeaders(to request: inout URLRequest) {
+    request.setValue("AFFiNE/\(appVersion)", forHTTPHeaderField: "User-Agent")
+    request.setValue(appVersion, forHTTPHeaderField: "x-affine-version")
+  }
+
+  private struct Request: Encodable {
+    var url: String
+    var include: [String]
+  }
+
+  private struct AppConfig: Decodable {
+    var affineVersion: String
+  }
+
+  private static var bundledAppVersion: String {
+    if let url = Bundle.main.url(forResource: "capacitor.config", withExtension: "json"),
+       let data = try? Data(contentsOf: url),
+       let version = try? JSONDecoder().decode(AppConfig.self, from: data).affineVersion,
+       !version.isEmpty
+    {
+      return version
+    }
+    if let version = Bundle.main.object(
+      forInfoDictionaryKey: "CFBundleShortVersionString"
+    ) as? String, !version.isEmpty {
+      return version
+    }
+    return "0.2"
+  }
+}