import {
  APIKey,
  AuthStatus,
  DashboardStats,
  Document,
  DocumentBlock,
  DocShare,
  DocLockInfo,
  KanbanColumn,
  ListItem,
  ListShare,
  Organization,
  PriorityLevel,
  SharedList,
  SharedFolder,
  FolderShare,
  Space,
  SpaceMember,
  SpaceShare,
  SystemSettings,
  Team,
  TaskList,
  TaskListShare,
  Thought,
  SubTask,
  TagDetails,
  TagSummary,
  User,
  UserInvite,
  WSMessage,
} from './types';

const TOKEN_STORAGE_KEY = 'mindsift_jwt_token';
const OFFLINE_QUEUE_KEY = 'mindsift_offline_capture_queue';

export function getToken(): string | null {
  return localStorage.getItem(TOKEN_STORAGE_KEY);
}

export function setToken(token: string): void {
  localStorage.setItem(TOKEN_STORAGE_KEY, token);
}

export function clearToken(): void {
  localStorage.removeItem(TOKEN_STORAGE_KEY);
}

export function triggerHaptic(pattern: number | number[] = 15): void {
  try {
    if (typeof navigator !== 'undefined' && 'vibrate' in navigator) {
      navigator.vibrate(pattern);
    }
  } catch {
    // Ignore on desktop browsers
  }
}

function ensureArray<T>(val: T[] | null | undefined): T[] {
  return Array.isArray(val) ? val : [];
}

async function request<T>(path: string, options: RequestInit = {}): Promise<T> {
  const token = getToken();
  const headers: Record<string, string> = {
    'Content-Type': 'application/json',
    'Cache-Control': 'no-cache',
    ...(options.headers as Record<string, string>),
  };

  if (token) {
    headers['Authorization'] = `Bearer ${token}`;
  }

  const controller = new AbortController();
  const timeoutId = window.setTimeout(() => controller.abort(), 12000);

  let res: Response;
  try {
    res = await fetch(path, {
      ...options,
      headers,
      cache: 'no-store',
      signal: controller.signal,
    });
  } finally {
    window.clearTimeout(timeoutId);
  }

  if (
    res.status === 401 &&
    !path.includes('/auth/login') &&
    !path.includes('/auth/register') &&
    !path.includes('/auth/setup') &&
    !path.includes('/auth/status')
  ) {
    clearToken();
    window.dispatchEvent(new CustomEvent('mindsift:unauthorized'));
  }

  if (!res.ok) {
    let errMsg = `HTTP ${res.status}`;
    try {
      const errData = await res.json();
      if (errData.error) errMsg = errData.error;
    } catch {
      // ignore
    }
    throw new Error(errMsg);
  }

  return res.json();
}

export const api = {
  // --- AUTH, FIRST-BOOT SETUP & SETTINGS ---
  async getAuthStatus(): Promise<AuthStatus> {
    return request<AuthStatus>('/api/v1/auth/status');
  },

  async completeSetup(payload: {
    email: string;
    password: string;
    displayName: string;
    instanceName?: string;
    sharingMode?: 'open' | 'teams_only' | 'strict_private';
    allowRegistration?: boolean;
    createSampleData?: boolean;
  }): Promise<{ token: string; user: User }> {
    const res = await request<{ token: string; user: User }>('/api/v1/auth/setup', {
      method: 'POST',
      body: JSON.stringify(payload),
    });
    setToken(res.token);
    return res;
  },

  async login(loginOrEmail: string, password: string): Promise<{ token: string; user: User }> {
    const res = await request<{ token: string; user: User }>('/api/v1/auth/login', {
      method: 'POST',
      body: JSON.stringify({ email: loginOrEmail, username: loginOrEmail, login: loginOrEmail, password }),
    });
    setToken(res.token);
    return res;
  },

  async register(
    email: string,
    password: string,
    displayName: string,
    inviteCode?: string
  ): Promise<{ token: string; user: User }> {
    const res = await request<{ token: string; user: User }>('/api/v1/auth/register', {
      method: 'POST',
      body: JSON.stringify({ email, password, displayName, inviteCode: inviteCode || '' }),
    });
    setToken(res.token);
    return res;
  },

  async getMe(): Promise<{ user: User; stats: DashboardStats }> {
    return request<{ user: User; stats: DashboardStats }>('/api/v1/auth/me');
  },

  async updateSettings(patch: {
    displayName?: string;
    email?: string;
    password?: string;
    avatarUrl?: string;
    alarmChannels?: string[];
    alarmEmail?: string;
    discordWebhookUrl?: string;
    customWebhookUrl?: string;
    notifyBeforeMinutes?: number;
  }): Promise<User> {
    return request<User>('/api/v1/auth/settings', {
      method: 'PATCH',
      body: JSON.stringify(patch),
    });
  },

  async testAlarmChannel(
    channel: 'email' | 'discord' | 'webhook',
    target?: string
  ): Promise<{ status: string }> {
    return request<{ status: string }>('/api/v1/auth/alarms/test', {
      method: 'POST',
      body: JSON.stringify({ channel, target: target || '' }),
    });
  },

  async getStats(): Promise<DashboardStats> {
    return request<DashboardStats>('/api/v1/stats');
  },

  async getUsersDirectory(): Promise<User[]> {
    const res = await request<User[]>('/api/v1/users/directory');
    return ensureArray(res);
  },

  // --- INSTANT CAPTURE & OFFLINE SYNC ---
  async captureThought(
    content: string,
    priority: PriorityLevel = 'normal',
    source: 'manual' | 'voice' = 'manual',
    dueDate = '',
    options?: {
      target?: 'inbox' | 'task' | 'list_item' | 'document';
      targetListId?: string;
      taskListId?: string;
    }
  ): Promise<Thought> {
    try {
      const thought = await request<Thought>('/api/v1/inbox', {
        method: 'POST',
        body: JSON.stringify({
          content,
          priority,
          source,
          dueDate,
          target: options?.target || 'inbox',
          targetListId: options?.targetListId || '',
          taskListId: options?.taskListId || '',
        }),
      });
      return thought;
    } catch {
      // Queue locally if offline
      const queue = getOfflineQueue();
      const offlineThought: Thought = {
        id: `th_offline_${Date.now()}`,
        userId: 'offline',
        content,
        tags: (content.match(/#([a-zA-Z0-9äöüÄÖÜß_-]+)/g) || []).map((t) => t.slice(1).toLowerCase()),
        priority,
        source,
        status: 'inbox',
        isCompleted: false,
        dueDate,
        taskListId: options?.taskListId || '',
        createdAt: new Date().toISOString(),
      };
      queue.push(offlineThought);
      localStorage.setItem(OFFLINE_QUEUE_KEY, JSON.stringify(queue));
      return offlineThought;
    }
  },

  async flushOfflineQueue(): Promise<number> {
    const queue = getOfflineQueue();
    if (queue.length === 0) return 0;

    let synced = 0;
    const remaining: Thought[] = [];

    for (const item of queue) {
      try {
        await request<Thought>('/api/v1/inbox', {
          method: 'POST',
          body: JSON.stringify({
            content: item.content,
            priority: item.priority,
            source: item.source,
            dueDate: item.dueDate || '',
            taskListId: item.taskListId || '',
          }),
        });
        synced++;
      } catch {
        remaining.push(item);
      }
    }

    localStorage.setItem(OFFLINE_QUEUE_KEY, JSON.stringify(remaining));
    return synced;
  },

  // --- THOUGHTS, TRIAGE & TASKS ---
  async getTriageDeck(): Promise<Thought[]> {
    const res = await request<Thought[]>('/api/v1/triage/deck');
    return ensureArray(res);
  },

  async getThoughts(status = 'all'): Promise<Thought[]> {
    const res = await request<Thought[]>(`/api/v1/thoughts?status=${encodeURIComponent(status)}`);
    return ensureArray(res);
  },

  async triageAction(
    thoughtId: string,
    action: 'keep' | 'discard' | 'restore',
    options?: {
      convertTo?: 'task' | 'document' | 'list_item';
      targetListId?: string;
      taskListId?: string;
      dueDate?: string;
    }
  ): Promise<Thought> {
    return request<Thought>(`/api/v1/triage/${thoughtId}`, {
      method: 'PATCH',
      body: JSON.stringify({
        action,
        convertTo: options?.convertTo || '',
        targetListId: options?.targetListId || '',
        taskListId: options?.taskListId || '',
        dueDate: options?.dueDate || '',
      }),
    });
  },

  async getTasks(taskListId?: string): Promise<Thought[]> {
    const query = taskListId ? `?taskListId=${encodeURIComponent(taskListId)}` : '';
    const res = await request<Thought[]>(`/api/v1/tasks${query}`);
    return ensureArray(res);
  },

  async reorderTasks(items: { id: string; sortOrder: number; kanbanStatus?: string }[], taskListId?: string): Promise<{ success: boolean }> {
    const url = taskListId ? `/api/v1/task-lists/${taskListId}/tasks/reorder` : '/api/v1/tasks/reorder';
    return request<{ success: boolean }>(url, {
      method: 'POST',
      body: JSON.stringify({ items }),
    });
  },

  async updateThought(
    thoughtId: string,
    patch: {
      content?: string;
      isCompleted?: boolean;
      dueDate?: string;
      priority?: string;
      taskListId?: string;
      kanbanStatus?: string;
      notes?: string;
      subtasks?: SubTask[];
      tags?: string[];
    }
  ): Promise<Thought> {
    return request<Thought>(`/api/v1/thoughts/${thoughtId}`, {
      method: 'PATCH',
      body: JSON.stringify(patch),
    });
  },

  async deleteThought(thoughtId: string): Promise<void> {
    await request(`/api/v1/thoughts/${thoughtId}`, { method: 'DELETE' });
  },

  async purgeDiscarded(): Promise<{ purged: number }> {
    return request<{ purged: number }>('/api/v1/thoughts/discarded/purge', { method: 'DELETE' });
  },

  // --- TASK LISTS ---
  async getTaskLists(): Promise<TaskList[]> {
    const res = await request<TaskList[]>('/api/v1/task-lists');
    return ensureArray(res).map((tl) => ({
      ...tl,
      members: ensureArray(tl.members),
      shares: ensureArray(tl.shares),
      columns: ensureArray(tl.columns),
    }));
  },

  async createTaskList(payload: {
    title: string;
    icon?: string;
    color?: string;
    teamId?: string;
    spaceId?: string;
    columns?: KanbanColumn[];
  }): Promise<TaskList> {
    return request<TaskList>('/api/v1/task-lists', {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async updateTaskList(
    id: string,
    patch: {
      title?: string;
      icon?: string;
      color?: string;
      teamId?: string;
      spaceId?: string;
      columns?: KanbanColumn[];
    }
  ): Promise<TaskList> {
    return request<TaskList>(`/api/v1/task-lists/${id}`, {
      method: 'PUT',
      body: JSON.stringify(patch),
    });
  },

  async deleteTaskList(id: string): Promise<void> {
    await request(`/api/v1/task-lists/${id}`, { method: 'DELETE' });
  },

  async getTaskListShares(id: string): Promise<TaskListShare[]> {
    const res = await request<TaskListShare[]>(`/api/v1/task-lists/${id}/shares`);
    return ensureArray(res);
  },

  async addTaskListShare(
    id: string,
    payload: { targetType: 'team' | 'user'; targetId: string }
  ): Promise<TaskListShare> {
    return request<TaskListShare>(`/api/v1/task-lists/${id}/shares`, {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async removeTaskListShare(id: string, shareId: string): Promise<void> {
    await request(`/api/v1/task-lists/${id}/shares/${shareId}`, { method: 'DELETE' });
  },

  // --- WORKSPACE FOLDERS ---
  async getFolders(): Promise<string[]> {
    const res = await request<string[]>('/api/v1/folders');
    return ensureArray(res);
  },

  async createFolder(path: string): Promise<{ path: string }> {
    return request<{ path: string }>('/api/v1/folders', {
      method: 'POST',
      body: JSON.stringify({ path }),
    });
  },

  async deleteFolder(path: string): Promise<{ deleted: boolean; deletedDocIds: string[] }> {
    return request<{ deleted: boolean; deletedDocIds: string[] }>(
      `/api/v1/folders?path=${encodeURIComponent(path)}`,
      { method: 'DELETE' }
    );
  },

  async moveFolder(sourcePath: string, targetParentPath: string): Promise<{ newPath: string; movedDocIds: string[] }> {
    return request<{ newPath: string; movedDocIds: string[] }>('/api/v1/folders/move', {
      method: 'POST',
      body: JSON.stringify({ sourcePath, targetParentPath }),
    });
  },

  // --- WORKSPACE SHARED FOLDERS ---
  async getSharedFolders(): Promise<SharedFolder[]> {
    const res = await request<SharedFolder[]>('/api/v1/workspace/folders/shared');
    return ensureArray(res);
  },

  async createSharedFolder(payload: { name: string; mountPath?: string }): Promise<SharedFolder> {
    return request<SharedFolder>('/api/v1/workspace/folders/shared', {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async getSharedFolder(id: string): Promise<SharedFolder> {
    return request<SharedFolder>(`/api/v1/workspace/folders/shared/${id}`);
  },

  async deleteSharedFolder(id: string): Promise<void> {
    await request(`/api/v1/workspace/folders/shared/${id}`, { method: 'DELETE' });
  },

  async updateFolderMount(id: string, mountPath: string): Promise<void> {
    await request(`/api/v1/workspace/folders/shared/${id}/mount`, {
      method: 'PUT',
      body: JSON.stringify({ mountPath }),
    });
  },

  async getFolderShares(folderId: string): Promise<FolderShare[]> {
    const res = await request<FolderShare[]>(`/api/v1/workspace/folders/shared/${folderId}/shares`);
    return ensureArray(res);
  },

  async createFolderShare(
    folderId: string,
    payload: { targetType?: 'team' | 'user'; targetId?: string; userId?: string; email?: string; teamId?: string; permission: 'read' | 'write' }
  ): Promise<FolderShare> {
    return request<FolderShare>(`/api/v1/workspace/folders/shared/${folderId}/shares`, {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async deleteFolderShare(folderId: string, shareId: string): Promise<void> {
    await request(`/api/v1/workspace/folders/shared/${folderId}/shares/${shareId}`, { method: 'DELETE' });
  },

  // --- WORKSPACE TAGS ---
  async getWorkspaceTags(): Promise<TagSummary[]> {
    const res = await request<TagSummary[]>('/api/v1/workspace/tags');
    return ensureArray(res);
  },

  async getTagDetails(tag: string): Promise<TagDetails> {
    const clean = encodeURIComponent(tag.replace(/^#/, ''));
    const res = await request<TagDetails>(`/api/v1/workspace/tags/${clean}`);
    return {
      ...res,
      documents: ensureArray(res.documents).map((doc) => ({
        ...doc,
        matchedBlocks: ensureArray(doc.matchedBlocks).map((mb) => ({
          rootBlock: mb.rootBlock,
          children: ensureArray(mb.children),
        })),
      })),
    };
  },

  async updateTagPageNote(
    tag: string,
    content: string
  ): Promise<{ tag: string; content: string; updatedAt: string }> {
    const clean = encodeURIComponent(tag.replace(/^#/, ''));
    return request<{ tag: string; content: string; updatedAt: string }>(
      `/api/v1/workspace/tags/${clean}/note`,
      {
        method: 'PUT',
        body: JSON.stringify({ content }),
      }
    );
  },

  // --- WORKSPACE DOCUMENTS ---
  async getDocuments(): Promise<Document[]> {
    const res = await request<Document[]>('/api/v1/documents');
    return ensureArray(res).map((d) => ({
      ...d,
      blocks: ensureArray(d.blocks),
      tags: ensureArray(d.tags),
    }));
  },

  async getDocument(id: string): Promise<Document> {
    const d = await request<Document>(`/api/v1/documents/${id}`);
    return {
      ...d,
      blocks: ensureArray(d.blocks),
      tags: ensureArray(d.tags),
    };
  },

  async createDocument(payload: {
    title: string;
    icon?: string;
    folderPath?: string;
    blocks?: DocumentBlock[];
    tags?: string[];
    isPinned?: boolean;
  }): Promise<Document> {
    const d = await request<Document>('/api/v1/documents', {
      method: 'POST',
      body: JSON.stringify(payload),
    });
    return {
      ...d,
      blocks: ensureArray(d.blocks),
      tags: ensureArray(d.tags),
    };
  },

  async updateDocument(
    id: string,
    patch: {
      title?: string;
      icon?: string;
      folderPath?: string;
      blocks?: DocumentBlock[];
      tags?: string[];
      isPinned?: boolean;
    }
  ): Promise<Document> {
    const d = await request<Document>(`/api/v1/documents/${id}`, {
      method: 'PUT',
      body: JSON.stringify(patch),
    });
    return {
      ...d,
      blocks: ensureArray(d.blocks),
      tags: ensureArray(d.tags),
    };
  },

  async patchDocumentBlocks(
    id: string,
    payload: {
      upserted?: DocumentBlock[];
      deletedIds?: string[];
      blockOrder?: string[];
    }
  ): Promise<Document> {
    const d = await request<Document>(`/api/v1/documents/${id}/blocks`, {
      method: 'PATCH',
      body: JSON.stringify(payload),
    });
    return {
      ...d,
      blocks: ensureArray(d.blocks),
      tags: ensureArray(d.tags),
    };
  },

  async getDocumentCRDT(id: string): Promise<{ docId: string; state?: string; updates?: string[] }> {
    return request<{ docId: string; state?: string; updates?: string[] }>(`/api/v1/documents/${id}/crdt`);
  },

  async saveDocumentCRDT(id: string, payload: string | { state?: string; update?: string }): Promise<{ success: boolean }> {
    const body = typeof payload === 'string' ? { state: payload } : payload;
    return request<{ success: boolean }>(`/api/v1/documents/${id}/crdt`, {
      method: 'PUT',
      body: JSON.stringify(body),
    });
  },

  async sendDocumentAwareness(id: string, payload: any): Promise<{ success: boolean }> {
    return request<{ success: boolean }>(`/api/v1/documents/${id}/awareness`, {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async clearDocumentAwareness(id: string): Promise<{ success: boolean }> {
    return request<{ success: boolean }>(`/api/v1/documents/${id}/awareness`, {
      method: 'DELETE',
    });
  },

  async joinSSERoom(sseId: string, room: string, action: 'join' | 'leave' = 'join'): Promise<{ success: boolean }> {
    return request<{ success: boolean }>('/api/v1/events/rooms', {
      method: 'POST',
      body: JSON.stringify({ sseId, room, action }),
    });
  },

  async deleteDocument(id: string): Promise<void> {
    await request(`/api/v1/documents/${id}`, { method: 'DELETE' });
  },

  async moveDocument(id: string, folderPath: string): Promise<Document> {
    const d = await request<Document>(`/api/v1/documents/${id}/move`, {
      method: 'PUT',
      body: JSON.stringify({ folderPath }),
    });
    return {
      ...d,
      blocks: ensureArray(d.blocks),
      tags: ensureArray(d.tags),
    };
  },

  // --- DOCUMENT SHARING ---
  async getDocShares(docId: string): Promise<DocShare[]> {
    const res = await request<DocShare[]>(`/api/v1/documents/${docId}/shares`);
    return ensureArray(res);
  },

  async createDocShare(
    docId: string,
    payload: { userId?: string; email?: string; teamId?: string; permission: 'read' | 'write' }
  ): Promise<DocShare> {
    return request<DocShare>(`/api/v1/documents/${docId}/shares`, {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async deleteDocShare(docId: string, userId: string): Promise<void> {
    await request(`/api/v1/documents/${docId}/shares/${userId}`, { method: 'DELETE' });
  },

  async getCollaborators(): Promise<User[]> {
    const res = await request<User[]>('/api/v1/collaborators');
    return ensureArray(res);
  },

  // --- DOCUMENT LOCKING ---
  async getDocLock(docId: string): Promise<{ locked: boolean; lock?: DocLockInfo }> {
    return request<{ locked: boolean; lock?: DocLockInfo }>(`/api/v1/documents/${docId}/lock`);
  },

  async lockDocument(
    docId: string
  ): Promise<{ locked: boolean; acquired: boolean; lock?: DocLockInfo; message?: string }> {
    try {
      return await request<{ locked: boolean; acquired: boolean; lock?: DocLockInfo; message?: string }>(
        `/api/v1/documents/${docId}/lock`,
        { method: 'POST' }
      );
    } catch (e: any) {
      return { locked: true, acquired: false, message: e.message };
    }
  },

  async heartbeatDocLock(docId: string): Promise<{ extended: boolean }> {
    try {
      return await request<{ extended: boolean }>(`/api/v1/documents/${docId}/lock/heartbeat`, {
        method: 'POST',
      });
    } catch {
      return { extended: false };
    }
  },

  async unlockDocument(docId: string): Promise<{ unlocked: boolean }> {
    try {
      return await request<{ unlocked: boolean }>(`/api/v1/documents/${docId}/lock`, {
        method: 'DELETE',
      });
    } catch {
      return { unlocked: false };
    }
  },

  // --- SPACES & REALTIME LISTS ---
  async getSpaces(): Promise<Space[]> {
    const res = await request<Space[]>('/api/v1/spaces');
    return ensureArray(res).map((s) => ({
      ...s,
      members: ensureArray(s.members),
      shares: ensureArray(s.shares),
    }));
  },

  async getSpaceShares(spaceId: string): Promise<SpaceShare[]> {
    const res = await request<SpaceShare[]>(`/api/v1/spaces/${spaceId}/shares`);
    return ensureArray(res);
  },

  async createSpace(name: string, icon: string, description: string): Promise<Space> {
    return request<Space>('/api/v1/spaces', {
      method: 'POST',
      body: JSON.stringify({ name, icon, description }),
    });
  },

  async joinSpace(inviteCode: string): Promise<Space> {
    return request<Space>('/api/v1/spaces/join', {
      method: 'POST',
      body: JSON.stringify({ inviteCode }),
    });
  },

  async addSpaceMember(spaceId: string, target: { userId?: string; email?: string; teamId?: string; role?: string }): Promise<any> {
    return request<any>(`/api/v1/spaces/${spaceId}/members`, {
      method: 'POST',
      body: JSON.stringify(target),
    });
  },

  async removeSpaceMember(spaceId: string, userId: string): Promise<void> {
    await request(`/api/v1/spaces/${spaceId}/members/${userId}`, {
      method: 'DELETE',
    });
  },

  async getSpaceLists(spaceId: string): Promise<SharedList[]> {
    const res = await request<SharedList[]>(`/api/v1/spaces/${spaceId}/lists`);
    return ensureArray(res).map((l) => ({
      ...l,
      items: ensureArray(l.items),
    }));
  },

  async getAllLists(): Promise<SharedList[]> {
    const res = await request<SharedList[]>('/api/v1/lists');
    return ensureArray(res).map((l) => ({
      ...l,
      items: ensureArray(l.items),
      shares: ensureArray(l.shares),
    }));
  },

  async getListById(listId: string): Promise<SharedList> {
    const l = await request<SharedList>(`/api/v1/lists/${listId}`);
    return {
      ...l,
      items: ensureArray(l.items),
      shares: ensureArray(l.shares),
    };
  },

  async createList(titleOrSpaceId: string, titleOrIcon?: string, iconOrType?: string, listType?: 'shopping' | 'checklist' | 'vacation'): Promise<SharedList> {
    let title = titleOrSpaceId;
    let icon = titleOrIcon || '🛒';
    let type = (iconOrType as any) || 'shopping';
    if (listType !== undefined) {
      title = titleOrIcon || '';
      icon = iconOrType || '🛒';
      type = listType;
    }
    const l = await request<SharedList>('/api/v1/lists', {
      method: 'POST',
      body: JSON.stringify({ title, icon, listType: type }),
    });
    return {
      ...l,
      items: ensureArray(l.items),
      shares: ensureArray(l.shares),
    };
  },

  async deleteList(listId: string): Promise<void> {
    await request(`/api/v1/lists/${listId}`, { method: 'DELETE' });
  },

  async getListShares(listId: string): Promise<ListShare[]> {
    const res = await request<ListShare[]>(`/api/v1/lists/${listId}/shares`);
    return ensureArray(res);
  },

  async addListShare(listId: string, target: { targetType: 'team' | 'user'; targetId: string; role?: string }): Promise<ListShare> {
    return request<ListShare>(`/api/v1/lists/${listId}/shares`, {
      method: 'POST',
      body: JSON.stringify(target),
    });
  },

  async removeListShare(listId: string, shareId: string): Promise<void> {
    await request(`/api/v1/lists/${listId}/shares/${shareId}`, { method: 'DELETE' });
  },

  async createListItem(listId: string, content: string, category = '', quantity = ''): Promise<ListItem> {
    return request<ListItem>(`/api/v1/lists/${listId}/items`, {
      method: 'POST',
      body: JSON.stringify({ content, category, quantity }),
    });
  },

  async toggleListItem(listId: string, itemId: string, isCompleted?: boolean): Promise<ListItem> {
    return request<ListItem>(`/api/v1/lists/${listId}/items/${itemId}`, {
      method: 'PATCH',
      body: JSON.stringify({ isCompleted }),
    });
  },

  async deleteListItem(listId: string, itemId: string): Promise<void> {
    await request(`/api/v1/lists/${listId}/items/${itemId}`, { method: 'DELETE' });
  },

  async clearCompletedItems(listId: string): Promise<{ removed: number }> {
    return request<{ removed: number }>(`/api/v1/lists/${listId}/clear-completed`, {
      method: 'POST',
    });
  },

  async reorderListItems(
    listId: string,
    items: { id: string; sortOrder: number; category?: string; content?: string }[]
  ): Promise<{ success: boolean }> {
    return request<{ success: boolean }>(`/api/v1/lists/${listId}/items/reorder`, {
      method: 'POST',
      body: JSON.stringify({ items }),
    });
  },

  // --- ORGANIZATIONS & TEAMS ---
  async getOrganizations(): Promise<Organization[]> {
    const res = await request<Organization[]>('/api/v1/organizations');
    return ensureArray(res).map((o) => ({
      ...o,
      teams: ensureArray(o.teams).map((t) => ({
        ...t,
        members: ensureArray(t.members),
      })),
    }));
  },

  async createOrganization(name: string): Promise<Organization> {
    return request<Organization>('/api/v1/organizations', {
      method: 'POST',
      body: JSON.stringify({ name }),
    });
  },

  async deleteOrganization(id: string): Promise<void> {
    await request(`/api/v1/organizations/${id}`, { method: 'DELETE' });
  },

  async getOrgTeams(orgId: string): Promise<Team[]> {
    const res = await request<Team[]>(`/api/v1/organizations/${orgId}/teams`);
    return ensureArray(res).map((t) => ({ ...t, members: ensureArray(t.members) }));
  },

  async createOrgTeam(orgId: string, name: string, description: string): Promise<Team> {
    return request<Team>(`/api/v1/organizations/${orgId}/teams`, {
      method: 'POST',
      body: JSON.stringify({ name, description }),
    });
  },

  async createTeam(name: string, description = ''): Promise<Team> {
    return request<Team>('/api/v1/teams', {
      method: 'POST',
      body: JSON.stringify({ name, description }),
    });
  },

  async updateTeam(teamId: string, name: string, description = ''): Promise<Team> {
    return request<Team>(`/api/v1/teams/${teamId}`, {
      method: 'PUT',
      body: JSON.stringify({ name, description }),
    });
  },

  async deleteTeam(teamId: string): Promise<void> {
    await request(`/api/v1/teams/${teamId}`, { method: 'DELETE' });
  },

  async getUserTeams(): Promise<Team[]> {
    const res = await request<Team[]>('/api/v1/teams');
    return ensureArray(res).map((t) => ({ ...t, members: ensureArray(t.members) }));
  },

  async addTeamMember(
    teamId: string,
    payload: { userId?: string; email?: string; role: string }
  ): Promise<void> {
    await request(`/api/v1/teams/${teamId}/members`, {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async updateTeamMemberRole(
    teamId: string,
    userId: string,
    role: 'admin' | 'member'
  ): Promise<void> {
    await request(`/api/v1/teams/${teamId}/members/${userId}`, {
      method: 'PUT',
      body: JSON.stringify({ role }),
    });
  },

  async removeTeamMember(teamId: string, userId: string): Promise<void> {
    await request(`/api/v1/teams/${teamId}/members/${userId}`, { method: 'DELETE' });
  },

  // --- ADMIN & STAFF PANEL ---
  async adminGetUsers(): Promise<User[]> {
    const res = await request<User[]>('/api/v1/admin/users');
    return ensureArray(res);
  },

  async adminCreateUser(payload: {
    email: string;
    password: string;
    displayName: string;
    role: string;
  }): Promise<User> {
    return request<User>('/api/v1/admin/users', {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async adminUpdateUser(
    id: string,
    patch: {
      displayName?: string;
      email?: string;
      role?: string;
      isActive?: boolean;
      discordWebhookUrl?: string;
    }
  ): Promise<User> {
    return request<User>(`/api/v1/admin/users/${id}`, {
      method: 'PATCH',
      body: JSON.stringify(patch),
    });
  },

  async adminResetPassword(id: string, password: string): Promise<void> {
    await request(`/api/v1/admin/users/${id}/password`, {
      method: 'PUT',
      body: JSON.stringify({ password }),
    });
  },

  async adminDeleteUser(id: string): Promise<void> {
    await request(`/api/v1/admin/users/${id}`, { method: 'DELETE' });
  },

  async adminGetInvites(): Promise<UserInvite[]> {
    const res = await request<UserInvite[]>('/api/v1/admin/invites');
    return ensureArray(res);
  },

  async adminCreateInvite(payload: {
    email?: string;
    role: string;
    teamId?: string;
  }): Promise<UserInvite> {
    return request<UserInvite>('/api/v1/admin/invites', {
      method: 'POST',
      body: JSON.stringify(payload),
    });
  },

  async adminDeleteInvite(id: string): Promise<void> {
    await request(`/api/v1/admin/invites/${id}`, { method: 'DELETE' });
  },

  async adminGetSettings(): Promise<SystemSettings> {
    return request<SystemSettings>('/api/v1/admin/settings');
  },

  async adminUpdateSettings(settings: SystemSettings): Promise<SystemSettings> {
    return request<SystemSettings>('/api/v1/admin/settings', {
      method: 'PUT',
      body: JSON.stringify(settings),
    });
  },

  async adminTestSMTP(toEmail: string): Promise<{ status: string }> {
    return request<{ status: string }>('/api/v1/admin/smtp/test', {
      method: 'POST',
      body: JSON.stringify({ toEmail }),
    });
  },

  // --- API KEYS, WEBHOOKS & EXPORT ---
  async getAPIKeys(): Promise<APIKey[]> {
    const res = await request<APIKey[]>('/api/v1/keys');
    return ensureArray(res);
  },

  async createAPIKey(name: string): Promise<APIKey> {
    return request<APIKey>('/api/v1/keys', {
      method: 'POST',
      body: JSON.stringify({ name }),
    });
  },

  async deleteAPIKey(id: string): Promise<void> {
    await request(`/api/v1/keys/${id}`, { method: 'DELETE' });
  },

  async testWebhookIngest(
    token: string,
    title: string,
    priority: PriorityLevel,
    tags: string[]
  ): Promise<{ status: string; thought: Thought }> {
    return request<{ status: string; thought: Thought }>(
      `/api/v1/webhooks/ingest?token=${encodeURIComponent(token)}`,
      {
        method: 'POST',
        body: JSON.stringify({ title, priority, tags }),
      }
    );
  },

  async searchAll(q: string): Promise<{ thoughts: Thought[]; documents: Document[] }> {
    return request<{ thoughts: Thought[]; documents: Document[] }>(
      `/api/v1/search?q=${encodeURIComponent(q)}`
    );
  },

  async exportAll(): Promise<any> {
    return request<any>('/api/v1/export');
  },
};

export function getOfflineQueue(): Thought[] {
  try {
    const raw = localStorage.getItem(OFFLINE_QUEUE_KEY);
    if (!raw) return [];
    return JSON.parse(raw);
  } catch {
    return [];
  }
}

export type RealtimeTransport = 'ws' | 'sse' | 'none';

let activeTransport: RealtimeTransport = 'none';
let activeGlobalWS: WebSocket | null = null;
let activeGlobalSSE: EventSource | null = null;
let activeSSEId: string | null = null;
let wsReconnectTimer: any = null;
let wsConnectionWatchdog: any = null;
let wsListeners: ((msg: WSMessage) => void)[] = [];
let realtimeStatusListeners: ((connected: boolean, transport: RealtimeTransport) => void)[] = [];
let isRealtimeConnectedState = false;
let manualDisconnect = false;
let wsReconnectDelay = 2000;

export function buildWebSocketURL(listId?: string): string {
  const protocol = window.location.protocol === 'https:' ? 'wss:' : 'ws:';
  const token = getToken() || '';
  if (listId) {
    return `${protocol}//${window.location.host}/api/v1/ws/lists/${encodeURIComponent(listId)}?token=${encodeURIComponent(token)}`;
  }
  return `${protocol}//${window.location.host}/api/v1/ws?token=${encodeURIComponent(token)}`;
}

export function buildSSEURL(listId?: string, docId?: string, rooms?: string[]): string {
  const token = getToken() || '';
  const params = new URLSearchParams();
  if (token) params.set('token', token);
  if (listId) params.set('listId', listId);
  if (docId) params.set('docId', docId);
  if (rooms && rooms.length > 0) params.set('rooms', rooms.join(','));
  return `/api/v1/events?${params.toString()}`;
}

export function isWebSocketConnected(): boolean {
  return activeTransport === 'ws' && activeGlobalWS !== null && activeGlobalWS.readyState === WebSocket.OPEN;
}

export function isRealtimeConnected(): boolean {
  return isRealtimeConnectedState;
}

export function getRealtimeTransport(): RealtimeTransport {
  return activeTransport;
}

export function getSSEId(): string | null {
  return activeSSEId;
}

export function onWebSocketStatus(callback: (connected: boolean) => void): () => void {
  const wrapper = (connected: boolean) => callback(connected);
  realtimeStatusListeners.push(wrapper);
  callback(isRealtimeConnected());
  return () => {
    realtimeStatusListeners = realtimeStatusListeners.filter((fn) => fn !== wrapper);
  };
}

export function onRealtimeStatus(callback: (connected: boolean, transport: RealtimeTransport) => void): () => void {
  realtimeStatusListeners.push(callback);
  callback(isRealtimeConnected(), activeTransport);
  return () => {
    realtimeStatusListeners = realtimeStatusListeners.filter((fn) => fn !== callback);
  };
}

let isWsBlockedByProxy = false;
let sseReconnectTimer: any = null;
let sseReconnectDelay = 2000;
const globalSubscribedRooms = new Set<string>();

function notifyRealtimeStatusChange(connected: boolean, transport: RealtimeTransport) {
  isRealtimeConnectedState = connected;
  activeTransport = transport;
  realtimeStatusListeners.forEach((fn) => {
    try {
      fn(connected, transport);
    } catch (e) {
      console.error('Realtime status listener error', e);
    }
  });
  window.dispatchEvent(new CustomEvent('mindsift:ws:status', { detail: { connected, transport } }));
}

export function connectSSE(rooms?: string[]): void {
  if (rooms) {
    rooms.forEach((r) => globalSubscribedRooms.add(r));
  }
  clearTimeout(sseReconnectTimer);
  clearTimeout(wsReconnectTimer);
  clearTimeout(wsConnectionWatchdog);

  if (activeGlobalSSE) {
    try { activeGlobalSSE.close(); } catch {}
    activeGlobalSSE = null;
  }

  try {
    const url = buildSSEURL(undefined, undefined, Array.from(globalSubscribedRooms));
    const es = new EventSource(url);
    activeGlobalSSE = es;

    es.onopen = () => {
      console.info('[MindSift Realtime] Server-Sent Events (SSE) verbunden (Proxy-Fallback aktiv).');
      sseReconnectDelay = 2000;
      notifyRealtimeStatusChange(true, 'sse');
      if (activeSSEId && globalSubscribedRooms.size > 0) {
        globalSubscribedRooms.forEach((room) => {
          api.joinSSERoom(activeSSEId!, room, 'join').catch(() => {});
        });
      }
    };

    es.onmessage = (event) => {
      try {
        const msg = JSON.parse(event.data) as WSMessage;
        if (msg.event === 'SSE_CONNECTED') {
          activeSSEId = msg.payload?.sseId || null;
          if (activeSSEId && globalSubscribedRooms.size > 0) {
            globalSubscribedRooms.forEach((room) => {
              api.joinSSERoom(activeSSEId!, room, 'join').catch(() => {});
            });
          }
        }
        wsListeners.forEach((fn) => {
          try {
            fn(msg);
          } catch (e) {
            console.error('SSE listener error', e);
          }
        });
        window.dispatchEvent(new CustomEvent('mindsift:ws', { detail: msg }));
      } catch (err) {
        console.error('Failed to parse SSE message', err);
      }
    };

    es.onerror = (e) => {
      if (activeTransport === 'sse') {
        notifyRealtimeStatusChange(false, 'none');
      }
      try { es.close(); } catch {}
      activeGlobalSSE = null;
      if (!manualDisconnect && getToken()) {
        clearTimeout(sseReconnectTimer);
        const delay = sseReconnectDelay;
        sseReconnectDelay = Math.min(30000, Math.round(sseReconnectDelay * 1.5));
        sseReconnectTimer = setTimeout(() => {
          if (!manualDisconnect && getToken()) {
            if (isWsBlockedByProxy) {
              connectSSE();
            } else {
              connectWebSocket();
            }
          }
        }, delay);
      }
    };
  } catch (err) {
    console.error('Failed to initialize EventSource SSE', err);
    notifyRealtimeStatusChange(false, 'none');
  }
}

export function connectWebSocket(): void {
  const token = getToken();
  if (!token) return;
  manualDisconnect = false;

  // If proxy blocked WebSocket previously, do not attempt failing WebSocket; stay on SSE
  if (isWsBlockedByProxy) {
    connectSSE();
    return;
  }

  if (activeGlobalWS && (activeGlobalWS.readyState === WebSocket.OPEN || activeGlobalWS.readyState === WebSocket.CONNECTING)) {
    return;
  }

  clearTimeout(wsConnectionWatchdog);
  clearTimeout(wsReconnectTimer);
  clearTimeout(sseReconnectTimer);

  try {
    const url = buildWebSocketURL();
    const ws = new WebSocket(url);
    activeGlobalWS = ws;

    // 3.5s watchdog for corporate proxies silently stripping Upgrade header
    wsConnectionWatchdog = setTimeout(() => {
      if (ws && ws.readyState !== WebSocket.OPEN) {
        console.warn('[MindSift Realtime] WebSocket connection timeout (Proxy Upgrade Block). Wechsle automatisch zu SSE...');
        isWsBlockedByProxy = true;
        try { ws.close(); } catch {}
        activeGlobalWS = null;
        connectSSE();
      }
    }, 3500);

    ws.onopen = () => {
      clearTimeout(wsConnectionWatchdog);
      if (activeGlobalSSE) {
        try { activeGlobalSSE.close(); } catch {}
        activeGlobalSSE = null;
      }
      wsReconnectDelay = 2000;
      notifyRealtimeStatusChange(true, 'ws');
      if (globalSubscribedRooms.size > 0) {
        globalSubscribedRooms.forEach((room) => {
          try {
            ws.send(JSON.stringify({ event: 'JOIN_ROOM', room }));
          } catch {}
        });
      }
    };

    ws.onmessage = (event) => {
      try {
        const msg = JSON.parse(event.data) as WSMessage;
        wsListeners.forEach((fn) => {
          try {
            fn(msg);
          } catch (e) {
            console.error('WS listener error', e);
          }
        });
        window.dispatchEvent(new CustomEvent('mindsift:ws', { detail: msg }));
      } catch (err) {
        console.error('Failed to parse WS message', err);
      }
    };

    ws.onclose = (evt: CloseEvent) => {
      clearTimeout(wsConnectionWatchdog);
      activeGlobalWS = null;

      const isProxyIssue = evt?.code === 1006 || evt?.code === 1002 || evt?.code === 1008;
      if (isProxyIssue && !manualDisconnect && getToken()) {
        console.warn('[MindSift Realtime] Proxy/Firewall Inkompatibilität erkannt (Code ' + evt.code + '). Wechsle dauerhaft zu SSE...');
        isWsBlockedByProxy = true;
        connectSSE();
        return;
      }

      if (activeTransport === 'ws') {
        notifyRealtimeStatusChange(false, 'none');
      }

      if (!manualDisconnect && getToken() && activeTransport !== 'sse') {
        clearTimeout(wsReconnectTimer);
        const delay = wsReconnectDelay;
        wsReconnectDelay = Math.min(30000, Math.round(wsReconnectDelay * 1.5));
        wsReconnectTimer = setTimeout(() => {
          if (!manualDisconnect && getToken()) {
            connectWebSocket();
          }
        }, delay);
      }
    };

    ws.onerror = (e) => {
      clearTimeout(wsConnectionWatchdog);
      try {
        ws.close();
      } catch {}
    };
  } catch (e) {
    clearTimeout(wsConnectionWatchdog);
    isWsBlockedByProxy = true;
    connectSSE();
  }
}

// Ensure reconnect when browser recovers from sleep or tab visibility
if (typeof window !== 'undefined') {
  window.addEventListener('online', () => {
    if (getToken() && !isRealtimeConnected()) {
      if (isWsBlockedByProxy) {
        connectSSE();
      } else {
        connectWebSocket();
      }
    }
  });
  document.addEventListener('visibilitychange', () => {
    if (document.visibilityState === 'visible' && getToken() && !isRealtimeConnected()) {
      if (isWsBlockedByProxy) {
        connectSSE();
      } else {
        connectWebSocket();
      }
    }
  });
}

export function disconnectWebSocket(): void {
  manualDisconnect = true;
  clearTimeout(wsReconnectTimer);
  clearTimeout(wsConnectionWatchdog);
  clearTimeout(sseReconnectTimer);
  if (activeGlobalWS) {
    try {
      activeGlobalWS.close();
    } catch {}
    activeGlobalWS = null;
  }
  if (activeGlobalSSE) {
    try {
      activeGlobalSSE.close();
    } catch {}
    activeGlobalSSE = null;
  }
  notifyRealtimeStatusChange(false, 'none');
}

export function sendWebSocketMessage(msg: any): void {
  if (activeGlobalWS && activeGlobalWS.readyState === WebSocket.OPEN) {
    activeGlobalWS.send(typeof msg === 'string' ? msg : JSON.stringify(msg));
    return;
  }

  // SSE Fallback: dispatch via REST endpoints
  try {
    const parsed = typeof msg === 'string' ? JSON.parse(msg) : msg;
    if (parsed.event === 'CRDT_UPDATE' && parsed.docId) {
      api.saveDocumentCRDT(parsed.docId, { update: parsed.payload?.update }).catch(() => {});
    } else if (parsed.event === 'CRDT_AWARENESS' && parsed.docId) {
      api.sendDocumentAwareness(parsed.docId, parsed.payload).catch(() => {});
    } else if (parsed.event === 'CRDT_LEAVE' && parsed.docId) {
      api.clearDocumentAwareness(parsed.docId).catch(() => {});
      if (activeSSEId) api.joinSSERoom(activeSSEId, `doc:${parsed.docId}`, 'leave').catch(() => {});
    } else if (parsed.event === 'CRDT_JOIN' && parsed.docId) {
      if (activeSSEId) api.joinSSERoom(activeSSEId, `doc:${parsed.docId}`, 'join').catch(() => {});
    } else if (parsed.event === 'JOIN_ROOM' && parsed.room) {
      if (activeSSEId) api.joinSSERoom(activeSSEId, parsed.room, 'join').catch(() => {});
    } else if (parsed.event === 'LEAVE_ROOM' && parsed.room) {
      if (activeSSEId) api.joinSSERoom(activeSSEId, parsed.room, 'leave').catch(() => {});
    } else if (parsed.event === 'LOCK_DOC' && parsed.docId) {
      api.lockDocument(parsed.docId).catch(() => {});
    } else if (parsed.event === 'UNLOCK_DOC' && parsed.docId) {
      api.unlockDocument(parsed.docId).catch(() => {});
    }
  } catch (err) {
    console.error('Error dispatching fallback REST message for SSE:', err);
  }
}

export function onWebSocketMessage(callback: (msg: WSMessage) => void): () => void {
  wsListeners.push(callback);
  return () => {
    wsListeners = wsListeners.filter((fn) => fn !== callback);
  };
}

export function createRealtimeConnection(options: {
  listId?: string;
  docId?: string;
  rooms?: string[];
  onMessage?: (msg: WSMessage) => void;
  onStatusChange?: (status: { connected: boolean; transport: RealtimeTransport; reason?: string }) => void;
}) {
  let isClosed = false;

  const joinedRooms: string[] = [];
  if (options.docId) joinedRooms.push(`doc:${options.docId}`);
  if (options.listId) joinedRooms.push(options.listId);
  if (options.rooms) {
    options.rooms.forEach((r) => {
      if (!joinedRooms.includes(r)) joinedRooms.push(r);
    });
  }

  joinedRooms.forEach((r) => globalSubscribedRooms.add(r));

  // Subscribe to status changes
  const unsubStatus = onRealtimeStatus((connected, transport) => {
    if (isClosed) return;
    options.onStatusChange?.({
      connected,
      transport,
      reason: connected ? undefined : 'Verbindung getrennt',
    });
  });

  // Subscribe to messages
  let unsubMsg: (() => void) | null = null;
  if (options.onMessage) {
    unsubMsg = onWebSocketMessage((msg) => {
      if (isClosed) return;
      options.onMessage?.(msg);
    });
  }

  // Join rooms on the active connection
  const joinAll = () => {
    joinedRooms.forEach((r) => {
      if (r.startsWith('doc:')) {
        sendWebSocketMessage({ event: 'CRDT_JOIN', docId: r.slice(4) });
      } else {
        sendWebSocketMessage({ event: 'JOIN_ROOM', room: r });
      }
    });
  };

  if (isRealtimeConnected()) {
    joinAll();
  }

  const unsubRejoin = onRealtimeStatus((connected) => {
    if (isClosed) return;
    if (connected) {
      joinAll();
    }
  });

  return {
    getTransport: () => activeTransport,
    isConnected: () => isRealtimeConnected(),
    send: (msg: any) => {
      if (isClosed) return;
      sendWebSocketMessage(msg);
    },
    close: () => {
      isClosed = true;
      unsubStatus();
      unsubRejoin();
      if (unsubMsg) unsubMsg();
      joinedRooms.forEach((r) => {
        globalSubscribedRooms.delete(r);
        if (r.startsWith('doc:')) {
          sendWebSocketMessage({ event: 'CRDT_LEAVE', docId: r.slice(4) });
        } else {
          sendWebSocketMessage({ event: 'LEAVE_ROOM', room: r });
        }
      });
    },
  };
}