import { createReducer } from '@reduxjs/toolkit';
import { getStaffNotifications, markNotificationRead, clearNotifications } from './thunk';
import { NotificationItem } from '@interfaces';

export interface NotificationState {
  items: NotificationItem[];
  loading: boolean;
  error: string | null;
  hasFetched: boolean;
}

const initialState: NotificationState = {
  items: [],
  loading: false,
  error: null,
  hasFetched: false,
};

export const reducers = createReducer(initialState, builder => {
  builder
    .addCase(getStaffNotifications.pending, acc => {
      acc.loading = true;
      acc.error = null;
    })
    .addCase(getStaffNotifications.fulfilled, (acc, action) => {
      acc.loading = false;
      acc.items = action.payload;
      acc.error = null;
      acc.hasFetched = true;
    })
    .addCase(getStaffNotifications.rejected, (acc, action) => {
      acc.loading = false;
      acc.hasFetched = true;
      acc.error =
        (action.payload as string) ??
        action.error.message ??
        'Failed to load notifications';
    })
    .addCase(markNotificationRead.pending, (acc, action) => {
      // Optimistic update: mark as read immediately
      const item = acc.items.find(i => i.id === action.meta.arg.notificationId);
      if (item) {
        item.isread = '1';
      }
    })
    .addCase(markNotificationRead.rejected, (acc, action) => {
      // If it fails, revert it (simple approach: you could also re-fetch)
      const item = acc.items.find(i => i.id === action.meta.arg.notificationId);
      if (item) {
        item.isread = '0';
      }
      acc.error = (action.payload as string) ?? 'Failed to mark notification as read';
    })
    .addCase(clearNotifications.pending, (acc) => {
      // Optimistic update: clear items immediately
      acc.items = [];
    })
    .addCase(clearNotifications.rejected, (acc, action) => {
      acc.error = (action.payload as string) ?? 'Failed to clear notifications';
    });
});

export default reducers;