WealthySmart/frontend/src/hooks/useBudget.ts

import { useState } from 'react';
import { useQuery, useQueryClient } from '@tanstack/react-query';
import { toast } from 'sonner';
import {
  type RecurringItemCreate,
  type RecurringItemUpdate,
  getYearlyProjection,
  getMonthlyDetail,
  getRecurringItems,
  createRecurringItem,
  updateRecurringItem as apiUpdateItem,
  deleteRecurringItem as apiDeleteItem,
  upsertBalanceOverride,
  deleteBalanceOverride,
} from '@/lib/api';

/** All budget data hangs off the ['budget', ...] key family; every mutation
 * invalidates the family so projection, month detail and items stay in sync. */
export function useBudget(initialYear: number) {
  const queryClient = useQueryClient();
  const [year, setYear] = useState(initialYear);
  const [selectedMonth, setSelectedMonth] = useState<number>(
    new Date().getMonth() + 1,
  );

  const projectionQ = useQuery({
    queryKey: ['budget', 'projection', year],
    queryFn: () => getYearlyProjection(year).then((r) => r.data),
  });

  const monthDetailQ = useQuery({
    queryKey: ['budget', 'month', year, selectedMonth],
    queryFn: () => getMonthlyDetail(year, selectedMonth).then((r) => r.data),
    placeholderData: (prev) => prev, // keep last month visible while navigating
  });

  const recurringQ = useQuery({
    queryKey: ['budget', 'recurring'],
    queryFn: () => getRecurringItems().then((r) => r.data),
  });

  const invalidate = () =>
    queryClient.invalidateQueries({ queryKey: ['budget'] });

  async function mutateWithToast(
    action: () => Promise<unknown>,
    success: string,
    failure: string,
  ) {
    try {
      await action();
    } catch (err) {
      toast.error(failure);
      throw err;
    }
    toast.success(success);
    await invalidate();
  }

  return {
    year,
    setYear,
    selectedMonth,
    setSelectedMonth,
    projection: projectionQ.data ?? null,
    monthDetail: monthDetailQ.data ?? null,
    recurringItems: recurringQ.data ?? [],
    loading: projectionQ.isPending,
    monthLoading: monthDetailQ.isFetching,
    error: projectionQ.error ?? monthDetailQ.error ?? recurringQ.error ?? null,
    addItem: (data: RecurringItemCreate) =>
      mutateWithToast(
        () => createRecurringItem(data),
        'Item recurrente creado',
        'No se pudo crear el item',
      ),
    updateItem: (id: number, data: RecurringItemUpdate) =>
      mutateWithToast(
        () => apiUpdateItem(id, data),
        'Item recurrente actualizado',
        'No se pudo actualizar el item',
      ),
    deleteItem: (id: number) =>
      mutateWithToast(
        () => apiDeleteItem(id),
        'Item recurrente eliminado',
        'No se pudo eliminar el item',
      ),
    saveBalanceOverride: (overrideYear: number, month: number, value: number) =>
      mutateWithToast(
        () => upsertBalanceOverride(overrideYear, month, value),
        'Balance ajustado',
        'No se pudo ajustar el balance',
      ),
    clearBalanceOverride: (overrideYear: number, month: number) =>
      mutateWithToast(
        () => deleteBalanceOverride(overrideYear, month),
        'Ajuste de balance eliminado',
        'No se pudo eliminar el ajuste',
      ),
    refresh: invalidate,
  };
}