// src/components/RetirementPlanner.js
import React, { useEffect, useState, useCallback, useContext } from 'react';
import authFetch from '../utils/authFetch.js';
import ScenarioContainer from './ScenarioContainer.js';
import { Button } from './ui/button.js';
import RetirementChatBar from './RetirementChatBar.js';
import ScenarioDiffDrawer from './ScenarioDiffDrawer.js';
import ChatCtx from '../contexts/ChatCtx.js';

/* ------------------------------------------------------------------
 * tiny class‑name helper
 * ---------------------------------------------------------------- */
const cn = (...cls) => cls.filter(Boolean).join(' ');

/* ------------------------------------------------------------------
 * responsive helper – “mobile” = < 768px
 * ---------------------------------------------------------------- */
function useIsMobile () {
  const [mobile, setMobile] = useState(() => window.innerWidth < 768);
  useEffect(() => {
    const handler = () => setMobile(window.innerWidth < 768);
    window.addEventListener('resize', handler);
    return () => window.removeEventListener('resize', handler);
  }, []);
  return mobile;
}

/* ==================================================================
 * RetirementPlanner
 * ================================================================= */
export default function RetirementPlanner () {
  /* ---------------------------- state ----------------------------- */
  const [loading,  setLoading ] = useState(false);
  const [error,    setError   ] = useState(null);
  const [financialProfile, setFinancialProfile] = useState(null);
  const [scenarios, setScenarios]             = useState([]);

  const [selectedScenario, setSelectedScenario] = useState(null);
  const [chatOpen, setChatOpen]               = useState(false); // slide‑in flag
  const [diff, setDiff]                       = useState(null);
  const [simYearsMap, setSimYearsMap] = useState({});
  const isMobile = useIsMobile();
  const { openRetire } = useContext(ChatCtx);


  /* ----------------------- data loading -------------------------- */
  const loadAll = useCallback(async () => {
    try {
      setLoading(true); setError(null);
      /* financial profile ------------------------------------------------ */
      const finRes = await authFetch('/api/premium/financial-profile');
      if (!finRes.ok) throw new Error(`Financial profile error (${finRes.status})`);
      const finJson = await finRes.json();

      /* scenarios -------------------------------------------------------- */
      const scRes  = await authFetch('/api/premium/career-profile/all');
      if (!scRes.ok) throw new Error(`Scenario error (${scRes.status})`);
      const scJson = await scRes.json();

      setFinancialProfile(finJson);
      setScenarios(scJson.careerProfiles || []);
    } catch (e) {
      console.error('RetirementPlanner → loadAll', e);
      setError(e.message || 'Failed to load');
    } finally {
      setLoading(false);
    }
  }, []);

  useEffect(() => { loadAll(); }, [loadAll]);

  /* ------------------ scenario CRUD helpers ---------------------- */
  async function handleAddScenario () {
    try {
      const body = {
        career_name : `New Scenario ${new Date().toLocaleDateString()}`,
        status      : 'planned',
        start_date  : new Date().toISOString().slice(0, 10),
        college_enrollment_status : 'not_enrolled',
        currently_working         : 'no'
      };
      const r = await authFetch('/api/premium/career-profile', {
        method : 'POST',
        headers: { 'Content-Type': 'application/json' },
        body   : JSON.stringify(body)
      });
      if (!r.ok) throw new Error(r.status);
      await loadAll();
    } catch (e) {
      alert(`Add scenario failed (${e.message})`);
    }
  }

  async function handleRemoveScenario (id) {
    if (!window.confirm('Delete this scenario?')) return;
    const r = await authFetch(`/api/premium/career-profile/${id}`, { method: 'DELETE' });
    if (!r.ok) return alert(`Delete error (${r.status})`);
    await loadAll();
  }

  async function handleCloneScenario (src) {
    if (!src?.id) return;
    try {
      const r = await authFetch('/api/premium/career-profile/clone', {
        method : 'POST',
        headers: { 'Content-Type': 'application/json' },
        body   : JSON.stringify({ sourceId: src.id, overrides: {} })
      });
      if (!r.ok) throw new Error(`HTTP ${r.status}`);
      await loadAll();            // refresh scenarios list in state
    } catch (e) {
      alert(`Clone scenario failed (${e.message})`);
    }
  }

  /* ------------------ chat patch helper -------------------------- */
  const applyPatch = (id, patch) => {
    setScenarios(prev => {
      const base = prev.find(s => s.id === id);
      const next = prev.map(s => (s.id === id ? { ...s, ...patch } : s));
      setDiff({ base, patch });
      return next;
    });
  };

  /* --------------------------- guards ---------------------------- */
  if (loading) return <p className="p-6">Loading scenarios…</p>;
  if (error)   return <p className="p-6 text-red-600">{error}</p>;

  /* ----------------------- render body --------------------------- */
  const visibleTwo     = scenarios.slice(0, 2);
  const baselineId     = visibleTwo[0]?.id;
  const baselineYears  = simYearsMap[baselineId] ?? null;   // renamed

  return (
    <div className="flex flex-col md:flex-row h-full relative">
      {/* ================= MAIN COLUMN =========================== */}
      <main className="flex-1 p-4 overflow-y-auto">
        {/* desktop add */}
        {!isMobile && (
          <Button onClick={handleAddScenario} className="mb-4">
            + Add Scenario
          </Button>
        )}

        <div className="mx-auto max-w-screen-lg grid gap-6 md:grid-cols-2">
          {visibleTwo.map(sc => (
            <ScenarioContainer
              key={sc.id}
              scenario={sc}
              financialProfile={financialProfile}
              baselineYears={baselineYears}
              onClone={handleCloneScenario}
              onRemove={handleRemoveScenario}
            onAskAI={() => {                 /* ← only fires from the new button */
              setSelectedScenario(sc);
              openRetire({
                scenario: sc,
                scenarios, // ← pass this
                financialProfile,
                onScenarioPatch: applyPatch
              });
            }}
            onSimDone={(id, yrs) => {
              setSimYearsMap(prev => ({ ...prev, [id]: yrs }));
            }}
            />
          ))}
        </div>
      </main>

      {/* ================= MOBILE FABS ========================== */}
      {isMobile && (
  <button
    onClick={handleAddScenario}
    className="fixed bottom-4 right-4 rounded-full bg-green-600 p-4 text-white text-xl shadow-md z-40"
    aria-label="Add scenario"
  >
    ＋
  </button>
)}

      {/* ================= DIFF DRAWER ========================== */}
      {diff && (
        <ScenarioDiffDrawer
          base={diff.base}
          patch={diff.patch}
          onClose={() => setDiff(null)}
        />
      )}
    </div>
  );
}