const TOKEN_KEY = "sac_token";
const ROLE_KEY = "sac_role";

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

export function getRole(): string | null {
  return localStorage.getItem(ROLE_KEY);
}

export function isAdmin(): boolean {
  return getRole() === "admin";
}

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

export function setRole(role: string): void {
  localStorage.setItem(ROLE_KEY, role);
}

export function setAuth(token: string, role: string): void {
  setToken(token);
  setRole(role);
}

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

export class ApiError extends Error {
  status: number;

  constructor(message: string, status: number) {
    super(message);
    this.name = "ApiError";
    this.status = status;
  }
}

export function redirectToErrorPage(status: 401 | 403 | 429): void {
  window.location.href = `/${status}`;
}

export async function apiFetch<T>(path: string, init: RequestInit = {}): Promise<T> {
  const headers = new Headers(init.headers);
  if (!headers.has("Content-Type") && init.body) {
    headers.set("Content-Type", "application/json");
  }
  const token = getToken();
  const hadToken = !!token;
  if (token) {
    headers.set("Authorization", `Bearer ${token}`);
  }
  const res = await fetch(path, { ...init, headers });
  const text = await res.text();
  if (res.status === 401) {
    if (hadToken) {
      clearToken();
      redirectToErrorPage(401);
    }
    throw new ApiError(parseApiError(text) || "Unauthorized", 401);
  }
  if (res.status === 403) {
    if (hadToken) {
      redirectToErrorPage(403);
    }
    throw new ApiError(parseApiError(text) || "Forbidden", 403);
  }
  if (res.status === 429) {
    redirectToErrorPage(429);
    throw new ApiError(parseApiError(text) || "Too many requests", 429);
  }
  if (!res.ok) {
    throw new ApiError(parseApiError(text) || res.statusText, res.status);
  }
  if (!text) {
    return undefined as T;
  }
  return JSON.parse(text) as T;
}

export interface TokenResponse {
  access_token: string;
  token_type: string;
  username: string;
  role: string;
}

export interface MeResponse {
  username: string;
  role: string;
}

export function fetchMe(): Promise<MeResponse> {
  return apiFetch<MeResponse>("/api/v1/auth/me");
}

export function parseApiError(text: string): string {
  if (!text) return "";
  try {
    const data = JSON.parse(text) as { detail?: string | Array<{ msg?: string }> };
    if (typeof data.detail === "string") return data.detail;
    if (Array.isArray(data.detail)) {
      return data.detail.map((item) => item.msg ?? String(item)).join("; ");
    }
  } catch {
    /* plain text */
  }
  return text;
}

export interface UserSummary {
  id: number;
  username: string;
  role: string;
  is_active: boolean;
  created_at: string;
}

export interface UserListResponse {
  items: UserSummary[];
}

export interface UpdateUserPayload {
  username?: string;
  role?: string;
  password?: string;
  is_active?: boolean;
}

export function fetchUsers(): Promise<UserListResponse> {
  return apiFetch<UserListResponse>("/api/v1/users");
}

export function createUser(payload: {
  username: string;
  password: string;
  role: string;
}): Promise<UserSummary> {
  return apiFetch<UserSummary>("/api/v1/users", {
    method: "POST",
    body: JSON.stringify(payload),
  });
}

export function updateUser(userId: number, payload: UpdateUserPayload): Promise<UserSummary> {
  return apiFetch<UserSummary>(`/api/v1/users/${userId}`, {
    method: "PATCH",
    body: JSON.stringify(payload),
  });
}

export interface EventSummary {
  id: number;
  event_id: string;
  host_id: number;
  hostname: string;
  display_name?: string | null;
  product_version?: string | null;
  occurred_at: string;
  received_at: string;
  category: string;
  type: string;
  severity: string;
  title: string;
  summary: string;
  actor_user?: string | null;
}

export interface EventListResponse {
  items: EventSummary[];
  total: number;
  page: number;
  page_size: number;
}

export interface EventDetail extends EventSummary {
  details: Record<string, unknown> | null;
  raw: Record<string, unknown> | null;
  payload: Record<string, unknown>;
}

export interface HostSummary {
  id: number;
  hostname: string;
  display_name: string | null;
  os_family: string;
  os_version?: string | null;
  product: string;
  product_version: string | null;
  ipv4: string | null;
  last_seen_at: string;
  event_count: number | null;
  last_heartbeat_at: string | null;
  last_daily_report_at: string | null;
  last_inventory_at?: string | null;
  agent_status: "online" | "stale" | "unknown";
}

export interface HostDetail extends HostSummary {
  agent_instance_id: string | null;
  ipv6: string | null;
  tags: string[] | null;
  use_sac_mode: string | null;
  inventory: Record<string, unknown> | null;
  inventory_updated_at: string | null;
  created_at: string | null;
}

export function fetchHost(id: number): Promise<HostDetail> {
  return apiFetch<HostDetail>(`/api/v1/hosts/${id}`);
}

export function fetchRecentEvents(limit = 1): Promise<EventSummary[]> {
  return apiFetch<EventSummary[]>(`/api/v1/dashboards/recent-events?limit=${limit}`);
}

export interface HostListResponse {
  items: HostSummary[];
  total: number;
  page: number;
  page_size: number;
  latest_agent_versions?: Record<string, string>;
}

export interface ProblemSummary {
  id: number;
  host_id: number | null;
  hostname: string | null;
  display_name?: string | null;
  title: string;
  summary: string;
  severity: string;
  status: string;
  rule_id: string | null;
  fingerprint?: string;
  event_count?: number;
  last_seen_at?: string;
  created_at: string;
  updated_at: string;
}

export interface ProblemListResponse {
  items: ProblemSummary[];
  total: number;
  page: number;
  page_size: number;
}

export interface ProblemEventItem {
  id: number;
  event_id: string;
  occurred_at: string;
  type: string;
  severity: string;
  title: string;
  summary: string;
}

export interface ProblemDetail extends ProblemSummary {
  events: ProblemEventItem[];
}

export function fetchProblem(id: number): Promise<ProblemDetail> {
  return apiFetch<ProblemDetail>(`/api/v1/problems/${id}`);
}

export async function ackProblem(problemId: number): Promise<{ id: number; status: string }> {
  return apiFetch(`/api/v1/problems/${problemId}/ack`, { method: "POST" });
}

export async function resolveProblem(problemId: number): Promise<{ id: number; status: string }> {
  return apiFetch(`/api/v1/problems/${problemId}/resolve`, { method: "POST" });
}

export interface TopHostItem {
  host_id: number;
  hostname: string;
  display_name?: string | null;
  count: number;
}

export interface TopTypeItem {
  type: string;
  count: number;
}

export interface MobileSettings {
  devices_allowed: boolean;
  max_devices_per_user: number;
  min_app_version: string | null;
  fcm_enabled: boolean;
  fcm_configured: boolean;
  source: string;
}

export interface MobileEnrollmentCode {
  id: number;
  label: string;
  code_prefix: string;
  target_user_id: number | null;
  target_username: string | null;
  login_mode: string;
  max_uses: number;
  use_count: number;
  expires_at: string;
  revoked_at: string | null;
  created_at: string;
  is_active: boolean;
}

export interface MobileEnrollmentCodeCreated extends MobileEnrollmentCode {
  enrollment_code: string;
}

export interface MobileDevice {
  id: number;
  user_id: number;
  username: string;
  device_uuid: string;
  display_name: string;
  platform: string;
  app_version: string | null;
  has_fcm_token: boolean;
  enrolled_at: string;
  last_seen_at: string | null;
  revoked_at: string | null;
  is_active: boolean;
}

export function fetchMobileSettings(): Promise<MobileSettings> {
  return apiFetch<MobileSettings>("/api/v1/mobile/settings");
}

export function updateMobileSettings(payload: {
  devices_allowed: boolean;
  max_devices_per_user: number;
  min_app_version?: string | null;
}): Promise<MobileSettings> {
  return apiFetch<MobileSettings>("/api/v1/mobile/settings", {
    method: "PUT",
    body: JSON.stringify(payload),
  });
}

export function fetchMobileEnrollmentCodes(): Promise<MobileEnrollmentCode[]> {
  return apiFetch<MobileEnrollmentCode[]>("/api/v1/mobile/enrollment-codes");
}

export function createMobileEnrollmentCode(payload: {
  label?: string;
  target_user_id?: number | null;
  login_mode?: string;
  max_uses?: number;
  expires_in_hours?: number;
}): Promise<MobileEnrollmentCodeCreated> {
  return apiFetch<MobileEnrollmentCodeCreated>("/api/v1/mobile/enrollment-codes", {
    method: "POST",
    body: JSON.stringify(payload),
  });
}

export function revokeMobileEnrollmentCode(codeId: number): Promise<void> {
  return apiFetch<void>(`/api/v1/mobile/enrollment-codes/${codeId}`, { method: "DELETE" });
}

export function fetchMobileDevices(): Promise<MobileDevice[]> {
  return apiFetch<MobileDevice[]>("/api/v1/mobile/devices");
}

export function revokeMobileDevice(deviceId: number): Promise<MobileDevice> {
  return apiFetch<MobileDevice>(`/api/v1/mobile/devices/${deviceId}/revoke`, { method: "POST" });
}

export function deleteMobileDevice(deviceId: number): Promise<void> {
  return apiFetch<void>(`/api/v1/mobile/devices/${deviceId}`, { method: "DELETE" });
}

export function testMobileDevicePush(deviceId: number): Promise<{ message: string }> {
  return apiFetch(`/api/v1/mobile/devices/${deviceId}/test-push`, { method: "POST" });
}

export interface DashboardSummary {
  events_last_24h: number;
  hosts_total: number;
  hosts_stale: number;
  heartbeats_24h: number;
  daily_reports_24h: number;
  problems_open: number;
  problems_opened_24h: number;
  problems_resolved_24h: number;
  severity_24h: Record<string, number>;
  top_hosts: TopHostItem[];
  top_event_types: TopTypeItem[];
  recent_events: EventSummary[];
}