// In HealthState interface:
interface HealthState {
  // ... existing state ...
  waterLogs: WaterLog[];

  // ... existing actions ...
  fetchWaterLogs: (date: string) => Promise<void>;
  addWaterLog: (log: Omit<WaterLog, 'id' | 'createdAt'>) => Promise<void>;
  deleteWaterLog: (id: string) => Promise<void>;
}

// In the store creation:
export const useHealthStore = create<HealthState>((set, get) => ({
  // ... existing state ...
  waterLogs: [],

  // ... existing actions ...

  fetchWaterLogs: async (date: string) => {
    set({ isLoading: true, error: null });
    try {
      const response = await fetch(`/api/water-intake?date=${date}`);
      if (!response.ok) throw new Error('Failed to fetch water logs');
      const data = await response.json();
      set({ waterLogs: data, isLoading: false });
    } catch (err: any) {
      set({ error: err.message, isLoading: false });
      toast.error(err.message || 'Failed to fetch water logs');
    }
  },

  addWaterLog: async (log: Omit<WaterLog, 'id' | 'createdAt'>) => {
    set({ isLoading: true, error: null });
    try {
      const response = await fetch('/api/water-intake', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(log),
      });
      if (!response.ok) throw new Error('Failed to add water log');
      const newLog = await response.json();
      set({
        waterLogs: [...get().waterLogs, newLog],
        isLoading: false,
      });
      toast.success('Water intake logged');
    } catch (err: any) {
      set({ error: err.message, isLoading: false });
      toast.error(err.message || 'Failed to add water log');
    }
  },

  deleteWaterLog: async (id: string) => {
    set({ isLoading: true, error: null });
    try {
      const response = await fetch(`/api/water-intake?id=${id}`, {
        method: 'DELETE',
      });
      if (!response.ok) throw new Error('Failed to delete water log');
      set({
        waterLogs: get().waterLogs.filter((log) => log.id !== id),
        isLoading: false,
      });
      toast.success('Water log deleted');
    } catch (err: any) {
      set({ error: err.message, isLoading: false });
      toast.error(err.message || 'Failed to delete water log');
    }
  },
}));