import React, { createContext, useContext, useState, useEffect } from 'react';
import { API_CONFIG } from '../constants/api';

const BaseEnumsContext = createContext({ enums: null, refresh: () => {}, getEnums: async () => null });

export const BaseEnumsProvider = ({ children }) => {
  const [enums, setEnums] = useState(null);
  const [lastFetched, setLastFetched] = useState(0);
  const [branchesByRegion, setBranchesByRegion] = useState({});
  const [branchesFetchedAt, setBranchesFetchedAt] = useState(0);

  const fetchEnums = async () => {
    try {
      const res = await fetch(`${API_CONFIG.BASE_URL}${API_CONFIG.ENDPOINTS.ENUMS}`);
      const json = await res.json();
      setEnums(json);
      setLastFetched(Date.now());
    } catch (e) {
      console.warn('Failed to fetch base-app-enums', e.message);
    }
  };

  const fetchBranches = async () => {
    try {
      const res = await fetch(`${API_CONFIG.BASE_URL}/branches?groupBy=region`);
      const json = await res.json();
      setBranchesByRegion(json || {});
      setBranchesFetchedAt(Date.now());
    } catch (e) {
      console.warn('Failed to fetch branches', e.message);
    }
  };

  // initial fetch and 60s refresh
  useEffect(() => {
    fetchEnums();
    fetchBranches();
    const id = setInterval(fetchEnums, 60000);
    const idB = setInterval(fetchBranches, 60000);
    return () => { clearInterval(id); clearInterval(idB);} ;
  }, []);

  const getEnums = async () => {
    if (!enums || Date.now() - lastFetched > 60000) {
      await fetchEnums();
    }
    return enums;
  };

  const getLabel = (category, key) => {
    if (!enums || !enums[category]) return key;
    return enums[category][key] ?? key;
  };

  const getOptions = (category) => {
    if (!enums || !enums[category]) return [];
    return Object.entries(enums[category]).map(([value, label]) => ({ value, label }));
  };

  const getBranches = async (regionKey) => {
    if (Date.now() - branchesFetchedAt > 60000) {
      await fetchBranches();
    }
    return regionKey ? branchesByRegion[regionKey] || [] : [];
  };

  return (
    <BaseEnumsContext.Provider value={{ enums, refresh: fetchEnums, getEnums, getLabel, getOptions, getBranches }}>
      {children}
    </BaseEnumsContext.Provider>
  );
};

export const useBaseEnums = () => useContext(BaseEnumsContext);