import { createSlice, type PayloadAction } from '@reduxjs/toolkit';
import type { AuthState, LoginSuccessPayload } from '@/features/auth/authTypes';
import { STORAGE_KEYS } from '@/utils/storage';
import { clearAuthTokens, getAccessToken, isAccessTokenExpired, storeAuthTokens } from '@/utils/authToken';

const clearPersistedAuthState = () => {
  localStorage.removeItem(STORAGE_KEYS.accessToken);
  localStorage.removeItem(STORAGE_KEYS.user);
  localStorage.removeItem(STORAGE_KEYS.authState);
  clearAuthTokens();
};

const loadPersistedAuthState = (): AuthState => {
  const loggedOutState: AuthState = { user: null, accessToken: null, isAuthenticated: false };
  const storedAuth = localStorage.getItem(STORAGE_KEYS.authState);
  const storedAccessToken = getAccessToken();

  if (!storedAuth) {
    return loggedOutState;
  }

  try {
    const parsed = JSON.parse(storedAuth) as AuthState;
    const accessToken = parsed.accessToken || storedAccessToken;

    if (accessToken && parsed.user && !isAccessTokenExpired()) {
      return { user: parsed.user, accessToken, isAuthenticated: true };
    }
  } catch {
    // fall through to the logged-out default below
  }

  clearPersistedAuthState();
  return loggedOutState;
};

const authSlice = createSlice({
  name: 'auth',
  initialState: loadPersistedAuthState(),
  reducers: {
    loginSuccess: (state, action: PayloadAction<LoginSuccessPayload>) => {
      state.user = action.payload.user;
      state.accessToken = action.payload.accessToken;
      state.isAuthenticated = true;

      localStorage.setItem(STORAGE_KEYS.accessToken, action.payload.accessToken);
      localStorage.setItem(STORAGE_KEYS.user, JSON.stringify(action.payload.user));
      storeAuthTokens({
        access_token: action.payload.accessToken,
        refresh_token: action.payload.refreshToken ?? '',
      });
      localStorage.setItem(
        STORAGE_KEYS.authState,
        JSON.stringify({
          user: action.payload.user,
          accessToken: action.payload.accessToken,
          isAuthenticated: true,
        }),
      );
    },
    logout: (state) => {
      state.user = null;
      state.accessToken = null;
      state.isAuthenticated = false;

      clearPersistedAuthState();
    },
    hydrateAuth: () => loadPersistedAuthState(),
  },
});

export const { loginSuccess, logout, hydrateAuth } = authSlice.actions;
export default authSlice.reducer;