src/NexusReader.UI.Shared/Components/MarkdownEditor.razor

@@ -42,6 +42,7 @@
     private readonly CancellationTokenSource _cts = new();
     private IJSObjectReference? _module;
     private DotNetObjectReference<MarkdownEditor>? _dotNetHelper;
+    private string? _lastInitializedEditorId;
 
     private enum SaveStatus
     {
@@ -136,9 +137,11 @@
 
     protected override async Task OnAfterRenderAsync(bool firstRender)
     {
-        if (firstRender || _reinitializeEditor)
+        var shouldInit = (firstRender || _reinitializeEditor) && (EditorId != _lastInitializedEditorId);
+        if (shouldInit)
         {
             _reinitializeEditor = false;
+            _lastInitializedEditorId = EditorId; // Set immediately before any async yield to prevent concurrent triggers
 
             if (firstRender)
             {
@@ -153,7 +156,7 @@
                 {
                     _module = await JS.InvokeAsync<IJSObjectReference>(
                         "import", 
-                        "./_content/NexusReader.UI.Shared/js/milkdownWrapper.js"
+                        $"./_content/NexusReader.UI.Shared/js/milkdownWrapper.js?v={Guid.NewGuid():N}"
                     );
                 }
                 await _module.InvokeVoidAsync("initEditor", EditorId, _dotNetHelper, InitialMarkdown);
@@ -178,7 +181,7 @@
             {
                 _module = await JS.InvokeAsync<IJSObjectReference>(
                     "import", 
-                    "./_content/NexusReader.UI.Shared/js/milkdownWrapper.js"
+                    $"./_content/NexusReader.UI.Shared/js/milkdownWrapper.js?v={Guid.NewGuid():N}"
                 );
             }
 
@@ -507,11 +510,31 @@
             }
         }
 
+        try
+        {
+            // Always try to destroy via global window registration first to handle null _module
+            await JS.InvokeVoidAsync("milkdownWrapper.destroyEditor", EditorId);
+        }
+        catch
+        {
+            // Fallback to module if global is not set
+            if (_module is not null)
+            {
+                try
+                {
+                    await _module.InvokeVoidAsync("destroyEditor", EditorId);
+                }
+                catch
+                {
+                    // Fail silently
+                }
+            }
+        }
+
         try
         {
             if (_module is not null)
             {
-                await _module.InvokeVoidAsync("destroyEditor", EditorId);
                 await _module.DisposeAsync();
             }
         }

src/NexusReader.UI.Shared/Layout/MainHubLayout.razor

@@ -183,10 +183,11 @@
         InvokeAsync(StateHasChanged);
     }
 
-    protected override void OnAfterRender(bool firstRender)
+    protected override async Task OnAfterRenderAsync(bool firstRender)
     {
         if (firstRender)
         {
+            await ThemeService.InitializeAsync();
             _isFullyLoaded = true;
             StateHasChanged();
         }

src/NexusReader.UI.Shared/Layout/MainHubLayout.razor.css

@@ -354,6 +354,8 @@
 /* --- Desktop Sidebar: warm paper shadow --- */
 .theme-light ::deep .hub-sidebar {
     box-shadow: 4px 0 20px rgba(139, 130, 115, 0.08);
+    background: var(--bg-surface) !important;
+    border-right: 1px solid var(--border) !important;
 }
 
 /* --- Logo icon: remove neon glow --- */

src/NexusReader.UI.Shared/Pages/CreatorEdit.razor

@@ -2,66 +2,185 @@
 @page "/creator/edit/{BookId}/{ChapterId}"
 @layout MainHubLayout
 @attribute [Authorize]
+@using NexusReader.UI.Shared.Components
 
-<div class="creator-edit-fullscreen-wrapper">
+@if (_loadingChapters)
-    
+{
-    <div class="chapters-sidebar">
+    <div class="hub-loading" style="height: calc(100vh - 4rem); display: flex; flex-direction: column; justify-content: center; align-items: center; background-color: var(--bg-base);">
-        <div class="sidebar-meta-header">
+        <div class="nexus-loader"></div>
-            <h2>Rozdziały</h2>
+        <p style="margin-top: 1rem; color: var(--text-muted); font-family: var(--nexus-font-sans);">Ładowanie struktury książki...</p>
-        </div>
-        <div class="chapters-list-wrapper">
-            <div class="chapter-item active">
-                <div class="active-indicator"></div>
-                <i class="fa-solid fa-book-open chapter-icon"></i>
-                <span class="chapter-title-text">1. Rozdział 1: Wprowadzenie do Zen Mode</span>
-            </div>
-            <div class="chapter-item">
-                <i class="fa-solid fa-file-lines chapter-icon"></i>
-                <span class="chapter-title-text">2. Rozdział 2: Zabezpieczenia i Architektura</span>
-            </div>
-        </div>
     </div>
-
+}
-    <div class="editor-workspace-area">
+else
+{
+    <div class="creator-edit-fullscreen-wrapper">
         
-        <div class="editor-header-row">
+        <div class="chapters-sidebar">
-            <div class="title-zone">
+            <div class="sidebar-meta-header">
-                <h1 class="chapter-title">Rozdział 1: Wprowadzenie do Zen Mode</h1>
+                <h2>Rozdziały</h2>
             </div>
-            <div class="telemetry-zone">
+            <div class="chapters-list-wrapper">
-                <span class="chapter-id-badge">ID: @ChapterId</span>
+                @foreach (var ch in _chapters)
+                {
+                    var isActive = ch.Id == _activeChapterId;
+                    <a class="chapter-item @(isActive ? "active" : "")" href="/creator/edit/@BookId/@ch.Id">
+                        @if (isActive)
+                        {
+                            <div class="active-indicator"></div>
+                            <i class="fa-solid fa-book-open chapter-icon"></i>
+                        }
+                        else
+                        {
+                            <i class="fa-solid fa-file-lines chapter-icon"></i>
+                        }
+                        <span class="chapter-title-text">@ch.Title</span>
+                    </a>
+                }
             </div>
         </div>
 
-        <div class="editor-canvas-card">
+        <div class="editor-workspace-area">
             
-            <div class="milkdown-premium-container" spellcheck="false">
+            <div class="editor-header-row">
-                <div id="editor"></div>
+                <div class="title-zone">
-            </div>
+                    <h1 class="chapter-title">@_activeChapterTitle</h1>
-            
+                </div>
-            <div class="editor-footer-bar">
+                <div class="telemetry-zone">
-                <div class="cloud-status-container">
+                    <span class="chapter-id-badge">ID: @_activeChapterId</span>
-                    <span class="cloud-status-pulse"></span>
-                    <span class="cloud-status-text">Saved to Cloud</span>
                 </div>
-                
-                <button class="btn-nexus-premium" @onclick="FetchContent">
-                    <span>Fetch Markdown Content</span>
-                    <i class="fa-solid fa-arrow-right-long"></i>
-                </button>
             </div>
 
+            <div class="editor-canvas-card">
+                @if (_loadingChapter)
+                {
+                    <div class="hub-loading" style="height: 100%; display: flex; flex-direction: column; justify-content: center; align-items: center;">
+                        <div class="nexus-loader"></div>
+                        <p style="margin-top: 1rem; color: var(--text-muted); font-family: var(--nexus-font-sans);">Wczytywanie treści rozdziału...</p>
+                    </div>
+                }
+                else if (_isChapterLoaded)
+                {
+                    <div class="milkdown-premium-container" spellcheck="false">
+                        <MarkdownEditor @key="_activeChapterId"
+                                        ChapterId="_activeChapterId"
+                                        InitialMarkdown="@_initialMarkdown"
+                                        ShowFetchButton="false" />
+                    </div>
+                }
+                else
+                {
+                    <div style="height: 100%; display: flex; flex-direction: column; justify-content: center; align-items: center; color: var(--text-muted); font-family: var(--nexus-font-sans);">
+                        <p>Wybierz lub utwórz rozdział, aby rozpocząć edycję.</p>
+                    </div>
+                }
+            </div>
         </div>
     </div>
-</div>
+}
 
 @code {
+    [Inject] private HttpClient Http { get; set; } = default!;
+    [Inject] private NavigationManager NavigationManager { get; set; } = default!;
+
     [Parameter] public string BookId { get; set; } = string.Empty;
     [Parameter] public string ChapterId { get; set; } = string.Empty;
-    private string _retrievedMarkdown = string.Empty;
 
-    private async Task FetchContent()
+    private List<ChapterListItem> _chapters = new();
+    private Guid _parsedBookId = Guid.Empty;
+    private Guid _activeChapterId = Guid.Empty;
+    private string _activeChapterTitle = string.Empty;
+    private string _initialMarkdown = string.Empty;
+    private bool _loadingChapters = true;
+    private bool _loadingChapter = false;
+    private bool _isChapterLoaded = false;
+
+    private class ChapterListItem
     {
-        await Task.CompletedTask;
+        public Guid Id { get; set; }
+        public string Title { get; set; } = string.Empty;
+        public int SortOrder { get; set; }
+    }
+
+    private class ChapterDetail
+    {
+        public Guid Id { get; set; }
+        public string Title { get; set; } = string.Empty;
+        public string MarkdownContent { get; set; } = string.Empty;
+    }
+
+    protected override async Task OnParametersSetAsync()
+    {
+        await base.OnParametersSetAsync();
+
+        if (!Guid.TryParse(BookId, out var parsedBookId))
+        {
+            NavigationManager.NavigateTo("/creator");
+            return;
+        }
+
+        _parsedBookId = parsedBookId;
+
+        // Fetch chapters list if empty or if book ID has changed
+        if (_chapters.Count == 0)
+        {
+            _loadingChapters = true;
+            try
+            {
+                var chapters = await Http.GetFromJsonAsync<List<ChapterListItem>>($"/api/creator/books/{_parsedBookId}/chapters");
+                _chapters = chapters ?? new();
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine($"[CreatorEdit] Error fetching chapters list: {ex.Message}");
+            }
+            finally
+            {
+                _loadingChapters = false;
+            }
+        }
+
+        // If ChapterId is empty/null, select the first chapter from list and navigate
+        if (string.IsNullOrEmpty(ChapterId))
+        {
+            if (_chapters.Any())
+            {
+                NavigationManager.NavigateTo($"/creator/edit/{BookId}/{_chapters.First().Id}");
+            }
+            return;
+        }
+
+        if (Guid.TryParse(ChapterId, out var parsedChapterId))
+        {
+            // If active chapter changed, fetch its details
+            if (parsedChapterId != _activeChapterId)
+            {
+                _activeChapterId = parsedChapterId;
+                var ch = _chapters.FirstOrDefault(c => c.Id == _activeChapterId);
+                _activeChapterTitle = ch?.Title ?? "Rozdział";
+
+                _loadingChapter = true;
+                _isChapterLoaded = false;
+                StateHasChanged();
+
+                try
+                {
+                    var detail = await Http.GetFromJsonAsync<ChapterDetail>($"/api/chapters/{_activeChapterId}");
+                    if (detail != null)
+                    {
+                        _initialMarkdown = detail.MarkdownContent;
+                        _isChapterLoaded = true;
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Console.WriteLine($"[CreatorEdit] Error fetching chapter content: {ex.Message}");
+                }
+                finally
+                {
+                    _loadingChapter = false;
+                }
+            }
+        }
     }
 }
+

src/NexusReader.UI.Shared/Pages/CreatorEdit.razor.css

@@ -185,7 +185,7 @@
 }
 
 /* DEEP MOUNTING COMPONENT INTEROP */
-::deep .milkdown {
+.milkdown-premium-container ::deep .milkdown {
     background: transparent !important;
     box-shadow: none !important;
     border: none !important;
@@ -196,7 +196,7 @@
     width: 100%;
 }
 
-::deep .ProseMirror {
+.milkdown-premium-container ::deep .ProseMirror {
     color: #e4e1d9 !important;
     background-color: transparent !important;
     font-size: 1.15rem !important;
@@ -209,87 +209,132 @@
     width: 100%;
 }
 
-.theme-light ::deep .ProseMirror {
+.theme-light .milkdown-premium-container ::deep .ProseMirror {
     color: #2d2a26 !important;
 }
 
 /* Precise matching text selection token */
-::deep .ProseMirror ::selection {
+.milkdown-premium-container ::deep .ProseMirror ::selection {
     background-color: rgba(0, 255, 153, 0.2) !important;
 }
 
-.theme-light ::deep .ProseMirror ::selection {
+.theme-light .milkdown-premium-container ::deep .ProseMirror ::selection {
     background-color: rgba(16, 185, 129, 0.18) !important;
 }
 
 /* Core webkit custom scrollbar mapping */
-::deep .ProseMirror::-webkit-scrollbar {
+.milkdown-premium-container ::deep .ProseMirror::-webkit-scrollbar {
     width: 6px;
 }
-::deep .ProseMirror::-webkit-scrollbar-track {
+.milkdown-premium-container ::deep .ProseMirror::-webkit-scrollbar-track {
     background: transparent;
 }
-::deep .ProseMirror::-webkit-scrollbar-thumb {
+.milkdown-premium-container ::deep .ProseMirror::-webkit-scrollbar-thumb {
     background: rgba(255, 255, 255, 0.08);
     border-radius: 4px;
 }
 
-.theme-light ::deep .ProseMirror::-webkit-scrollbar-thumb {
+.theme-light .milkdown-premium-container ::deep .ProseMirror::-webkit-scrollbar-thumb {
     background: #dcd7cc;
 }
 
-/* 5. SEAMLESS INTEGRATED ACTIONS FOOTER BAR */
+/* 5. SEAMLESS INTEGRATED ACTIONS FOOTER BAR (OVERWRITING FOR MARKDOWNEDITOR COMPONENT INTEGRATION) */
-.editor-footer-bar {
+.milkdown-premium-container ::deep .markdown-editor-container {
+    display: flex;
+    flex-direction: column;
+    flex-grow: 1;
+    overflow: hidden;
+    height: 100%;
+}
+
+.milkdown-premium-container ::deep .milkdown-editor-wrapper {
+    background: transparent !important;
+    border: none !important;
+    box-shadow: none !important;
+    padding: 0 !important;
+    flex-grow: 1;
+    overflow: hidden !important;
+    display: flex;
+    flex-direction: column;
+}
+
+.milkdown-premium-container ::deep .milkdown {
+    flex-grow: 1;
+    overflow: hidden !important;
+}
+
+.milkdown-premium-container ::deep .editor-footer {
     display: flex;
     justify-content: space-between;
     align-items: center;
-    margin-top: 2rem;
+    margin-top: 2rem !important;
-    padding-top: 1.5rem;
+    padding: 1.5rem 0 0 0 !important;
-    border-top: 1px solid rgba(255, 255, 255, 0.04);
+    border: none !important;
+    border-top: 1px solid rgba(255, 255, 255, 0.04) !important;
+    background: transparent !important;
+    border-radius: 0 !important;
     flex-shrink: 0;
     width: 100%;
 }
 
-.theme-light .editor-footer-bar {
+.theme-light .milkdown-premium-container ::deep .editor-footer {
-    border-top: 1px solid #dcd7cc;
+    border-top: 1px solid #dcd7cc !important;
 }
 
-/* Telemetry cloud synchronization line */
+/* Telemetry cloud synchronization line mapping */
-.cloud-status-container {
+.milkdown-premium-container ::deep .status-indicator {
     display: flex;
     align-items: center;
     gap: 12px;
-}
-
-.cloud-status-pulse {
-    width: 7px;
-    height: 7px;
-    background-color: #00ff99;
-    border-radius: 50%;
-    display: inline-block;
-    box-shadow: 0 0 10px rgba(0, 255, 153, 0.8);
-}
-
-.theme-light .cloud-status-pulse {
-    background-color: #10b981;
-    box-shadow: 0 0 10px rgba(16, 185, 129, 0.6);
-}
-
-.cloud-status-text {
     font-family: 'Azeret Mono', monospace;
     font-size: 0.82rem;
     color: #71717a;
     letter-spacing: 0.1px;
 }
 
+.theme-light .milkdown-premium-container ::deep .status-indicator {
+    color: #78716c;
+}
+
+.milkdown-premium-container ::deep .status-dot {
+    width: 7px;
+    height: 7px;
+    border-radius: 50%;
+    display: inline-block;
+}
+
+.milkdown-premium-container ::deep .status-dot.saved {
+    background-color: #00ff99 !important;
+    box-shadow: 0 0 10px rgba(0, 255, 153, 0.8) !important;
+    color: #00ff99 !important;
+}
+
+.theme-light .milkdown-premium-container ::deep .status-dot.saved {
+    background-color: #10b981 !important;
+    box-shadow: 0 0 10px rgba(16, 185, 129, 0.6) !important;
+    color: #10b981 !important;
+}
+
+.milkdown-premium-container ::deep .status-dot.saving {
+    background-color: #F59E0B !important;
+    box-shadow: 0 0 10px rgba(245, 158, 11, 0.8) !important;
+    color: #F59E0B !important;
+}
+
+.milkdown-premium-container ::deep .status-dot.offline {
+    background-color: #EF4444 !important;
+    box-shadow: 0 0 10px rgba(239, 68, 68, 0.8) !important;
+    color: #EF4444 !important;
+}
+
 /* Premium Tactile Operational Button Trigger */
-.btn-nexus-premium {
+.milkdown-premium-container ::deep .nexus-btn {
     background-color: #00ff99 !important;
     color: #121214 !important;
     font-weight: 700;
     font-size: 0.9rem;
     letter-spacing: -0.1px;
-    padding: 11px 24px;
+    padding: 11px 24px !important;
     border: none !important;
     border-radius: 10px;
     cursor: pointer;
@@ -298,28 +343,23 @@
     gap: 10px;
     transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
     box-shadow: 0 4px 20px rgba(0, 255, 153, 0.15);
+    height: auto !important;
+    min-height: unset !important;
 }
 
-.theme-light .btn-nexus-premium {
+.theme-light .milkdown-premium-container ::deep .nexus-btn {
     background-color: #10b981 !important;
     color: #ffffff !important;
     box-shadow: 0 4px 20px rgba(16, 185, 129, 0.15);
 }
 
-.btn-nexus-premium i {
+.milkdown-premium-container ::deep .nexus-btn:hover {
-    font-size: 0.85rem;
-    transition: transform 0.2s ease;
-}
-
-.btn-nexus-premium:hover {
     transform: translateY(-1px);
     box-shadow: 0 8px 24px rgba(0, 255, 153, 0.3);
 }
 
-.theme-light .btn-nexus-premium:hover {
+.theme-light .milkdown-premium-container ::deep .nexus-btn:hover {
     box-shadow: 0 8px 24px rgba(16, 185, 129, 0.3);
 }
 
-.btn-nexus-premium:hover i {
+
-    transform: translateX(3px);
-}

src/NexusReader.UI.Shared/wwwroot/js/milkdownWrapper.js

@@ -1,5 +1,11 @@
-// Map to keep track of active Crepe editor instances by elementId (container ID)
+// Initialize global stores on window to share state across dynamically imported module instances (preventing cache-buster isolation)
-const editorCache = new Map();
+if (typeof window !== 'undefined') {
+    if (!window.editorCache) window.editorCache = new Map();
+    if (!window.editorStates) window.editorStates = new Map();
+}
+
+const editorCache = typeof window !== 'undefined' ? window.editorCache : new Map();
+const editorStates = typeof window !== 'undefined' ? window.editorStates : new Map();
 
 /**
  * Asynchronously injects a stylesheet link tag into the document head
@@ -23,19 +29,64 @@ async function ensureStylesheet(href) {
  * Initializes a Milkdown Crepe editor on the specified element.
  */
 export async function initEditor(elementId, dotNetHelper, initialMarkdown) {
+    // Check if already destroyed or initializing
+    if (editorStates.get(elementId) === 'destroyed') {
+        console.warn(`[Milkdown] initEditor called on already destroyed element: ${elementId}. Aborting.`);
+        return;
+    }
+    if (editorStates.get(elementId) === 'initializing' || editorStates.get(elementId) === 'ready') {
+        console.warn(`[Milkdown] Editor is already initializing or ready for element: ${elementId}. Ignoring.`);
+        return;
+    }
+
+    editorStates.set(elementId, 'initializing');
+
+    // Guard 1: Destroy previous cached editor instance with the same ID if it exists
+    if (editorCache.has(elementId)) {
+        console.warn(`[Milkdown] Editor instance already exists in cache for: ${elementId}. Destroying first.`);
+        await destroyEditor(elementId);
+    }
+
     const container = document.getElementById(elementId);
     if (!container) {
         console.error(`[Milkdown] Container with ID "${elementId}" not found.`);
+        editorStates.delete(elementId);
         return;
     }
 
+    // Guard 2: Clear container children to prevent double-initialization of crepe editor DOM
+    if (container.children.length > 0) {
+        console.warn(`[Milkdown] Container "${elementId}" is not empty. Clearing children before initialization.`);
+        container.innerHTML = '';
+    }
+
+    // Guard 3: Search the parent workspace card to purge any other leftover editor components
+    const parentCard = container.closest('.milkdown-premium-container') || container.parentElement;
+    if (parentCard) {
+        const existingEditors = parentCard.querySelectorAll('.milkdown, .crepe');
+        if (existingEditors.length > 0) {
+            console.warn(`[Milkdown] Found ${existingEditors.length} leftover editor DOM elements in the workspace card. Purging them.`);
+            existingEditors.forEach(el => el.remove());
+        }
+    }
+
     try {
         // Condition 2: Prevent FOUC by loading stylesheets before instantiating the editor
         await ensureStylesheet('/_content/NexusReader.UI.Shared/css/vendor/milkdown-crepe.css');
 
+        if (editorStates.get(elementId) === 'destroyed') {
+            console.warn(`[Milkdown] Element ${elementId} destroyed during stylesheet loading. Aborting.`);
+            return;
+        }
+
         // Dynamically import the local JS bundle
         await import('/_content/NexusReader.UI.Shared/js/vendor/milkdown-crepe.js');
 
+        if (editorStates.get(elementId) === 'destroyed') {
+            console.warn(`[Milkdown] Element ${elementId} destroyed during crepe bundle loading. Aborting.`);
+            return;
+        }
+
         // Get Crepe constructor from the global window.milkdownCrepe namespace
         const Crepe = window.milkdownCrepe?.Crepe;
         if (!Crepe) {
@@ -100,6 +151,7 @@ export async function initEditor(elementId, dotNetHelper, initialMarkdown) {
                     clearTimeout(debounceTimeout);
                 }
                 debounceTimeout = setTimeout(() => {
+                    if (editorStates.get(elementId) === 'destroyed') return;
                     dotNetHelper.invokeMethodAsync('OnEditorContentChanged', markdown)
                         .catch(err => console.error("[Milkdown] Failed to notify editor content changed:", err));
                 }, 300);
@@ -112,8 +164,17 @@ export async function initEditor(elementId, dotNetHelper, initialMarkdown) {
         // Create the editor view asynchronously
         await crepe.create();
 
+        if (editorStates.get(elementId) === 'destroyed') {
+            console.warn(`[Milkdown] Element ${elementId} destroyed during crepe.create(). Cleaning up.`);
+            await crepe.destroy();
+            editorCache.delete(elementId);
+            return;
+        }
+
+        editorStates.set(elementId, 'ready');
         console.log(`[Milkdown] Editor successfully initialized on element: ${elementId}`);
     } catch (error) {
+        editorStates.delete(elementId);
         console.error(`[Milkdown] Failed to initialize editor on "${elementId}":`, error);
     }
 }
@@ -134,6 +195,8 @@ export function getMarkdownContent(elementId) {
  * Safely disposes of the editor instance to prevent memory leaks in WASM.
  */
 export async function destroyEditor(elementId) {
+    editorStates.set(elementId, 'destroyed');
+
     const crepe = editorCache.get(elementId);
     if (crepe) {
         try {
@@ -144,6 +207,12 @@ export async function destroyEditor(elementId) {
         }
         editorCache.delete(elementId);
     }
+    
+    // Explicitly clean up container DOM children
+    const container = document.getElementById(elementId);
+    if (container) {
+        container.innerHTML = '';
+    }
 }
 
 /**
@@ -163,3 +232,13 @@ export function getBackupKeys() {
     }
     return keys;
 }
+
+// Attach to window for global access (especially from DisposeAsync when module reference is null)
+if (typeof window !== 'undefined') {
+    window.milkdownWrapper = {
+        initEditor,
+        getMarkdownContent,
+        destroyEditor,
+        getBackupKeys
+    };
+}