Desktop app (#308)

* Implement build profiles and feature policy for offline desktop builds

* Introduce unified cross-platform Settings Hub

* Refactor main settings into a hierarchical page-based navigation model

* Refactor library projection to use shared multiplatform logic

* Refactor UI state consumption by removing intermediate screen models

* Introduce AndroidSharedStateBridge to centralize state mapping and reduction logic

* Refactor state management for tabs, selection, and pinning to use shared bridge logic

* Refactor file type management and validation into a centralized shared module

* Centralize file type resolution and improve handling of unknown types

* Centralize book import logic with SharedImportPlanner

* Refactor magnifier geometry logic and coordinate mapping

* Properly handle orientation changes in scroll-locked PDF reader

* Add screen orientation controls to EPUB and PDF readers

* Implement right-to-left (RTL) pagination support and refactor reader menus

* Separate right-to-left pagination settings for PDF and EPUB

* Ensure PDF page data is scoped by document key for multi tab support

* Implement theme-aware link styling for the epub reader

* Implement jump history for back and forward navigation in the epub reader

* Improve locator handling and navigation logic in paginated reader mode

* Implement stable pagination navigation and location tracking

* Centralize banner message management and auto-dismiss logic in MainViewModel

* Implement zoom and pan state preservation for PDF pan lock mode

* Enhance reader navigation UI and workspace layout management in desktop app

* Refactor reader navigation sidebar and relocate search controls in desktop app

* Enhance reader UI with redesigned selection menus and bottom sheet overlays

* Implement custom highlight palettes and reader theme customization in desktop app

* Implement cross-platform modal layer and refine reader UI styling

* Improve highlight accuracy and implement metadata enrichment on book open in desktop app

* Implement two-page spread layout for paginated reader on desktop

* Implement persistent caching for book loading and pagination in desktop app

* Implement persistent caching for book loading and pagination in desktop app

* Optimize reader settings updates by separating layout and appearance changes in desktop app

* Improve desktop window branding and native Windows styling

* Enhance reader selection interactions and UI across EPUB and PDF viewers in desktop app

* Refine selection handle positioning and interaction logic

* Implement EPUB selection debug logging and improve handle targeting

* Optimize desktop book loading performance and UI responsiveness

* Implement anchored zoom gestures and rendering optimizations for the Desktop PDF viewer.

* Implement smooth zoom preview for the PDF reader in desktop app

* Optimize PDF rendering performance and responsiveness in the desktop reader

* Implement conditional diagnostic logging and update desktop build configuration

* Implemented hierarchical TOC, custom scrollbars, and improved desktop modal handling

* Added management options for annotations and highlights in the sidebar in desktop app

* Implemented `SharedStableOutlinedTextField` and updated text input fields to use `TextFieldValue` for improved cursor and selection stability.

* Refined library filters and enhanced OPDS functionality in desktop app

* Improved EPUB pagination measurement and implemented layout diagnostic logging for desktop app

* Added PPTX support including document parsing, rendering, and indexing

* Improved PPTX rendering and layout accuracy

* Implemented text autofit support for PPTX rendering

* Enhanced PPTX rendering with support for custom geometry, automatic numbering, table styles, and image opacity

* Improved EPUB pagination accuracy and added layout telemetry in desktop app

* Improved folder synchronization with metadata-only mode and hashed sidecar management in desktop app

* Implemented rich text font scaling and migrated desktop ink tools to custom pointer input handling

* Implemented billing account obfuscation

* Implemented hierarchical folder navigation and improved library selection functionality in desktop app

* Implemented platform-aware directory resolution and multi-platform native library support for desktop

* Added full-screen mode for the reader workspace

* Added PDF zoom indicator and interactive vertical scrollbar with page tooltips

* Refactored speech bubble prefetching to use a limited radius and improved ML detector initialization and lifecycle management

* Updated PDF indexing to replace existing page text and removed search result item keys

* Implemented "preparing" foreground notification for TTS service

* Optimized PDF rendering performance by pre-calculating page-specific annotations

* Refactored desktop packaging tasks and improved distribution configuration

* Optimized EPUB parser memory usage and added path traversal protection

* Refactored WorkManager monitoring logic and added work pruning

* Implemented comprehensive resource cleanup and memory management for WebView-based components to prevent memory leaks

* Implemented bitmap size limits and scaling to prevent canvas rendering errors

* Split long text paragraphs into multiple semantic blocks during HTML parsing

* Implemented local ActionMode for text selection to prevent platform crashes

* Refactored PPTX text layout, optimized HtmlParser block detection, and improved banner dismissal logic

* Added desktop startup splash screen and deferred WebView initialization

* Reorganized settings hub and added separate PDF reader defaults

* Implemented embedded cover extraction and metadata support for MOBI and FB2 formats

* Implemented batching for MetadataExtractionWorker and optimized EPUB metadata extraction performance.

* Implemented procedurally generated book covers and replaced static placeholders

* Redesigned search UI with a top bar and results overlay in desktop app

* Added PDF page gap and overlay visibility options and implemented DesktopBookImporter

* Refactored PDF reader UI with tabbed inspector and improved theme background handling in desktop

* Implemented PDF viewport persistence for zoom and scroll positions in desktop app

* Improved desktop fullscreen implementation and state restoration

* Implemented desktop window state persistence

* Implemented flavor-based branding and ProGuard configuration for desktop builds

* Implemented precise reader positioning and improved highlight rendering logic in desktop app

* Added support for user-editable book metadata

* Enhanced book metadata support and integrated info/edit dialogs

* Implemented embedded EPUB metadata editing

* Improved highlight mapping and added custom scrollbar styling for the reader.

* Reduced desktop WebView bundle size by excluding unused locales and runtime files

* Added neutral pan mode as the default PDF interaction state.

* Refactored library empty states and updated primary navigation tabs in desktop app

* Implemented native paginated reader and unified content rendering architecture in desktop epub reader

* Implemented native EPUB image rendering for desktop and improved block layout spacing with margin collapsing.

* Improved pagination overflow detection in desktop

* Implemented multi-block text selection with interactive handles and CFI support in desktop epub pagination

app/src/main/java/com/aryan/reader/tts/TtsPlaybackManager.kt

@@ -83,7 +83,9 @@ private const val PREFETCH_LOOKAHEAD = 3
 class TtsPlaybackManager(
     private val player: Player,
     private val generateAudioChunk: suspend (bookTitle: String, chapterTitle: String?, chunkIndex: Int, totalChunks: Int, textChunk: String, speakerId: String, mode: TtsMode, authToken: String?) -> TtsAudioData,
-    private val onResetContext: () -> Unit
+    private val onResetContext: () -> Unit,
+    private val onPlaybackSessionPreparing: (bookTitle: String?, chapterTitle: String?) -> Unit = { _, _ -> },
+    private val onPlaybackSessionStopped: () -> Unit = {}
 ) : MediaSession.Callback, Player.Listener {
 
     private val scope = CoroutineScope(Dispatchers.IO + SupervisorJob())
@@ -415,6 +417,8 @@ class TtsPlaybackManager(
             handleStopTts(clearState = false)
         }
 
+        onPlaybackSessionPreparing(bookTitle, chapterTitle)
+
         textChunks = chunks
         currentSpeakerId = speakerId
         currentTtsMode = ttsMode
@@ -550,6 +554,7 @@ class TtsPlaybackManager(
         val firstChunk = textChunks.getOrNull(startAtIndex)
         if (firstChunk == null) {
             _ttsState.value = _ttsState.value.copy(isLoading = false, errorMessage = "Error starting playback.")
+            onPlaybackSessionStopped()
             return
         }
 
@@ -627,6 +632,7 @@ class TtsPlaybackManager(
                 isLoading = false,
                 errorMessage = ttsAudioData.error ?: "Failed to load audio."
             )
+            onPlaybackSessionStopped()
         }
     }
 
@@ -667,6 +673,7 @@ class TtsPlaybackManager(
         Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
             "handleStopTts. clearState=$clearState, userInitiated=$userInitiated"
         )
+        onPlaybackSessionStopped()
         onResetContext()
         preparationJob?.cancel()
         wordTrackingJob?.cancel()