import { makeAutoObservable, reaction, runInAction } from 'mobx';
import { AppState, type AppStateStatus } from 'react-native';
import { themeStore } from '@/shared/config';
import { appEvents, currentPosition, hydrateStorage, startGeoTracking, stopGeoTracking, storage } from '@/shared/lib';
import type { Driver, MrmAdmin } from '@/entities/driver/@x/session';
import { MessageStore } from '@/entities/message/@x/session';
import { loginByPin, loginMrm as loginMrmRequest, logout as logoutRequest, sendHeartbeat } from '@/entities/driver/@x/session';
import type { AppScreen, ThemeMode } from './types';
import {
  clearMrmAdmin,
  clearSession,
  persistDriver,
  persistMrmAdmin,
  persistSession,
  sessionStartedAt,
  storedDriver,
  storedMrmAdmin,
  storedToken,
} from './sessionStorage';

const HEARTBEAT_INTERVAL = 10_000;
const SPEED_INTERVAL = 3_000;

function themeStorageKey(driverId: string): string {
  return `kiosk:theme:${driverId}`;
}

export class SessionStore {
  readonly messageStore = new MessageStore();

  screen: AppScreen = 'login';
  driver: Driver | null = null;
  mrmAdmin: MrmAdmin | null = null;
  sessionKicked = false;
  ready = false;

  theme: ThemeMode = 'dark';
  isDark = true;

  isMoving = true;
  speed = 32;
  currentStopIndex = 3;

  loginError: string | null = null;
  loginLoading = false;

  private heartbeatTimer: ReturnType<typeof setInterval> | null = null;
  private speedTimer: ReturnType<typeof setInterval> | null = null;
  private appStateSub: { remove: () => void } | null = null;

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    reaction(
      () => this.isDark,
      (isDark) => themeStore.setDark(isDark),
      { fireImmediately: true },
    );
  }

  async init(): Promise<void> {
    if (this.ready) return;
    await hydrateStorage();
    runInAction(() => {
      this.driver = storedDriver();
      this.mrmAdmin = storedMrmAdmin();
      this.restore();
      this.ready = true;
    });
    this.start();
  }

  get messages() {
    return this.messageStore.messages;
  }

  get connection() {
    return this.messageStore.connection;
  }

  get pendingImportant() {
    return this.messageStore.pendingImportant;
  }

  get pendingCount() {
    return this.messageStore.pendingCount;
  }

  get unreadCount() {
    return this.messageStore.unreadCount;
  }

  private restore(): void {
    if (this.mrmAdmin) {
      this.screen = 'main';
    } else if (storedToken() && this.driver) {
      this.screen = 'main';
      this.messageStore.hydrateFromCache();
    }
    if (this.driver) this.applyStoredTheme(this.driver.id);
    this.isDark = this.theme === 'dark';
  }

  start(): void {
    this.speedTimer = setInterval(() => {
      if (this.screen !== 'main') return;
      runInAction(() => {
        this.speed = Math.max(0, Math.min(60, this.speed + (Math.random() - 0.5) * 8));
      });
    }, SPEED_INTERVAL);
    this.startSessionLoop();
  }

  stop(): void {
    if (this.speedTimer) clearInterval(this.speedTimer);
    this.stopSessionLoop();
    this.messageStore.stop();
  }

  private startSessionLoop(): void {
    if (this.screen === 'login' || this.screen === 'welcome') return;
    startGeoTracking();
    this.messageStore.start();
    void this.heartbeat();
    this.heartbeatTimer = setInterval(() => void this.heartbeat(), HEARTBEAT_INTERVAL);
    this.appStateSub = AppState.addEventListener('change', (state: AppStateStatus) => {
      if (state === 'active') void this.heartbeat();
    });
  }

  private stopSessionLoop(): void {
    if (this.heartbeatTimer) clearInterval(this.heartbeatTimer);
    this.heartbeatTimer = null;
    this.appStateSub?.remove();
    this.appStateSub = null;
    stopGeoTracking();
  }

  private async heartbeat(): Promise<void> {
    const result = await sendHeartbeat(
      storedToken(),
      currentPosition(),
      this.driver?.deviationSettings?.updatedAt ?? null,
    );
    if (result.sessionExpired) {
      runInAction(() => {
        this.sessionKicked = true;
        this.driver = null;
        this.screen = 'login';
      });
      clearSession();
      this.stopSessionLoop();
      return;
    }
    if (result.deviationSettings && this.driver) {
      runInAction(() => {
        this.driver = { ...this.driver!, deviationSettings: result.deviationSettings! };
      });
      persistDriver(this.driver);
    }
  }

  private applyStoredTheme(driverId: string): void {
    const raw = storage.get(themeStorageKey(driverId));
    if (raw === 'light' || raw === 'dark') this.theme = raw;
  }

  private mapDriver(raw: Record<string, unknown>): Driver {
    return {
      id: String(raw.id),
      name: raw.name as string,
      vehicleType: raw.vehicleType as Driver['vehicleType'],
      vehicleNumber: raw.vehicleNumber as string,
      routeNumber: raw.routeNumber as string,
      routeId: (raw.routeId as string) ?? undefined,
      shiftStart: (raw.shiftStart as string) || '08:00',
      dispatcherName: (raw.dispatcherName as string) ?? undefined,
      deviationSettings: (raw.deviationSettings as Driver['deviationSettings']) ?? undefined,
    };
  }

  async login(employeeId: string, pin: string): Promise<boolean> {
    this.loginError = null;
    this.loginLoading = true;
    this.sessionKicked = false;
    try {
      const { driver, token } = await loginByPin(employeeId, pin);
      persistSession(token, driver);
      runInAction(() => {
        this.driver = driver;
        this.messageStore.reset();
      });
      this.startShift();
      return true;
    } catch (error) {
      runInAction(() => {
        this.loginError = error instanceof Error ? error.message : 'Ошибка входа';
      });
      return false;
    } finally {
      runInAction(() => (this.loginLoading = false));
    }
  }

  loginSmsVerified(data: { token: string; driver: Record<string, unknown> }): void {
    const driver = this.mapDriver(data.driver);
    persistSession(data.token, driver);
    this.driver = driver;
    this.messageStore.reset();
    this.loginError = null;
    this.startShift();
  }

  async loginMrm(login: string, password: string): Promise<void> {
    this.loginError = null;
    this.loginLoading = true;
    try {
      const admin = await loginMrmRequest(login, password);
      persistMrmAdmin(admin);
      runInAction(() => {
        this.mrmAdmin = admin;
        this.screen = 'main';
      });
      this.startSessionLoop();
    } catch (error) {
      runInAction(() => {
        this.loginError = error instanceof Error ? error.message : 'Ошибка входа';
      });
    } finally {
      runInAction(() => (this.loginLoading = false));
    }
  }

  startShift(): void {
    this.screen = 'main';
    this.isMoving = true;
    this.startSessionLoop();
  }

  setScreen(screen: AppScreen): void {
    this.screen = screen;
  }

  async logout(): Promise<void> {
    const token = storedToken();
    clearSession();
    clearMrmAdmin();
    this.stopSessionLoop();
    this.messageStore.stop();
    runInAction(() => {
      this.driver = null;
      this.mrmAdmin = null;
      this.messageStore.reset();
      this.screen = 'login';
      this.isMoving = false;
    });
    await logoutRequest(token);
  }

  dismissSessionKicked(): void {
    this.sessionKicked = false;
  }

  toggleTheme(): void {
    this.theme = this.theme === 'light' ? 'dark' : 'light';
    this.isDark = this.theme === 'dark';
    this.persistTheme();
    appEvents.emit('theme:changed', this.theme);
  }

  setTheme(theme: ThemeMode): void {
    this.theme = theme;
    this.isDark = this.theme === 'dark';
    this.persistTheme();
  }

  private persistTheme(): void {
    if (!this.driver) return;
    storage.set(themeStorageKey(this.driver.id), this.theme);
  }

  get sessionStartedAt(): number | null {
    return sessionStartedAt();
  }
}

export const sessionStore = new SessionStore();