import { createContext, useContext, useEffect, useMemo, useState } from 'react';
import type { PropsWithChildren } from 'react';

interface OperationalContextValue {
  areaId: string;
  companyId: string;
  setAreaId: (areaId: string) => void;
  setCompanyId: (companyId: string) => void;
  setContext: (areaId: string, companyId?: string) => void;
  clearContext: () => void;
}

const STORAGE_KEY = 'dhv2.operational-context';
const OperationalContext = createContext<OperationalContextValue | null>(null);

function readStoredContext(): { areaId: string; companyId: string } {
  try {
    const raw = window.localStorage.getItem(STORAGE_KEY);
    if (!raw) return { areaId: '', companyId: '' };
    const parsed = JSON.parse(raw) as { areaId?: unknown; companyId?: unknown };
    return {
      areaId: typeof parsed.areaId === 'string' ? parsed.areaId : '',
      companyId: typeof parsed.companyId === 'string' ? parsed.companyId : '',
    };
  } catch {
    return { areaId: '', companyId: '' };
  }
}

export function OperationalContextProvider({ children }: PropsWithChildren) {
  const initial = useMemo(readStoredContext, []);
  const [areaId, setAreaState] = useState(initial.areaId);
  const [companyId, setCompanyState] = useState(initial.companyId);

  useEffect(() => {
    window.localStorage.setItem(STORAGE_KEY, JSON.stringify({ areaId, companyId }));
  }, [areaId, companyId]);

  const value = useMemo<OperationalContextValue>(() => ({
    areaId,
    companyId,
    setAreaId: (nextAreaId) => {
      setAreaState(nextAreaId);
      setCompanyState('');
    },
    setCompanyId: setCompanyState,
    setContext: (nextAreaId, nextCompanyId = '') => {
      setAreaState(nextAreaId);
      setCompanyState(nextAreaId ? nextCompanyId : '');
    },
    clearContext: () => {
      setAreaState('');
      setCompanyState('');
    },
  }), [areaId, companyId]);

  return <OperationalContext.Provider value={value}>{children}</OperationalContext.Provider>;
}

export function useOperationalContext() {
  const value = useContext(OperationalContext);
  if (!value) throw new Error('useOperationalContext debe usarse dentro de OperationalContextProvider');
  return value;
}