import { signal, computed } from '@preact/signals';
import { endpoints } from '../api/client';
import type { AuthLoginRequest, AuthLoginResponse, UserProfile } from '../api/types';

// Types
export interface UserPreferences {
  theme: 'light' | 'dark' | 'auto';
  sidebarCollapsed: boolean;
  panelHeight: number;
  defaultTeam: string;
  keyboardShortcutsEnabled: boolean;
  notificationsEnabled: boolean;
}

// Default preferences
const DEFAULT_PREFERENCES: UserPreferences = {
  theme: 'auto',
  sidebarCollapsed: false,
  panelHeight: 280,
  defaultTeam: 'ui',
  keyboardShortcutsEnabled: true,
  notificationsEnabled: true
};

// User State Signals
export const user = signal<UserProfile | null>(null);
export const preferences = signal<UserPreferences>(DEFAULT_PREFERENCES);

// Computed Values
export const isAuthenticated = computed(() => user.value !== null);
export const userId = computed(() => user.value?.id ?? 1);
export const userName = computed(() => user.value?.display_name ?? user.value?.email ?? 'Guest');
export const userInitials = computed(() => {
  const name = user.value?.display_name ?? user.value?.email ?? 'Guest';
  return name.split(' ').filter(Boolean).map(n => n[0]).join('').toUpperCase().slice(0, 2);
});

// Actions
export function loadUserPreferences(): void {
  if (typeof window === 'undefined') return;

  const saved = localStorage.getItem('dss-preferences');
  if (saved) {
    try {
      const parsed = JSON.parse(saved);
      preferences.value = { ...DEFAULT_PREFERENCES, ...parsed };
    } catch {
      preferences.value = DEFAULT_PREFERENCES;
    }
  }
}

export function saveUserPreferences(): void {
  if (typeof window === 'undefined') return;
  localStorage.setItem('dss-preferences', JSON.stringify(preferences.value));
}

export function updatePreferences(updates: Partial<UserPreferences>): void {
  preferences.value = { ...preferences.value, ...updates };
  saveUserPreferences();
}

export function setUser(userData: UserProfile | null): void {
  user.value = userData;
}

export function logout(): void {
  user.value = null;
  localStorage.removeItem('dss-token');
}

export async function refreshUser(): Promise<void> {
  if (typeof window === 'undefined') return;

  const token = localStorage.getItem('dss-token');
  if (!token) {
    user.value = null;
    return;
  }

  try {
    const profile = await endpoints.auth.me();
    user.value = profile;
  } catch {
    // Token is invalid/expired; clear it.
    localStorage.removeItem('dss-token');
    user.value = null;
  }
}

export async function loginWithAtlassian(credentials: AuthLoginRequest): Promise<AuthLoginResponse> {
  const response = await endpoints.auth.login(credentials);
  localStorage.setItem('dss-token', response.token);
  // Prefer server truth; also supports older login response shapes.
  user.value = {
    id: response.user.id,
    email: response.user.email,
    display_name: response.user.display_name,
    atlassian_url: response.user.atlassian_url,
    atlassian_service: response.user.service,
    last_login: new Date().toISOString(),
  };
  return response;
}

// Keyboard shortcuts state
export const keyboardShortcutsEnabled = computed(() =>
  preferences.value.keyboardShortcutsEnabled
);