let returnDocuments = [];
let editingReturnDocument = null;
const $return = id => document.getElementById(id);
const returnReviewYear = Number(new Intl.DateTimeFormat('en-US', {timeZone:'Asia/Seoul',year:'numeric'}).format(new Date()));

function returnDocumentYears(doc, byId) {
  const visited = new Set();
  while (doc && !visited.has(doc.id)) {
    visited.add(doc.id);
    const years = [...new Set([...(doc.events || []), ...(doc.policies || [])]
      .map(item => item.year).filter(year => Number.isInteger(year) && year >= 2000 && year <= 2100))];
    if (years.length) return years.sort((a,b) => a-b);
    // A withdrawal or unstructured correction can inherit its original's period.
    doc = byId.get(doc.supersedes_id);
  }
  return [];
}

function matchesReturnPeriod(years, period, currentYear = returnReviewYear) {
  if (period === 'all') return true;
  if (period === 'unknown') return years.length === 0;
  if (period === 'history') return years.some(year => year < currentYear);
  return years.some(year => year === currentYear || year === currentYear+1);
}

async function returnAdminRequest(path, options = {}) {
  const response = await fetch('/api/admin/returns/' + path, options);
  const data = await response.json();
  if (!response.ok) {
    if (response.status === 401 || response.status === 403) throw new Error('관리자 로그인이 필요합니다. 스크리너에서 로그인하세요.');
    const message = typeof data.detail === 'string' ? data.detail : Array.isArray(data.detail)
      ? data.detail.map(item => String(item.msg).replace(/^Value error, /,'')).join(' · ') : '요청을 처리하지 못했습니다.';
    throw new Error(message);
  }
  return data;
}

function adminMessage(message) { $return('admin-message').textContent = message; }
function field(label, name, value, type = 'text', choices = null) {
  const wrap = document.createElement('label');
  wrap.textContent = label;
  const input = document.createElement(choices ? 'select' : type === 'textarea' ? 'textarea' : 'input');
  input.name = name;
  if (choices) {
    for (const [key, text] of choices) input.add(new Option(text, key));
    input.value = String(value ?? choices[0][0]);
  } else if (type === 'checkbox') { input.type = type; input.checked = !!value; }
  else { if (type !== 'textarea') input.type = type; input.value = value ?? ''; }
  if (type === 'number') input.step = 'any';
  wrap.append(input);
  return wrap;
}

const returnScopes = [['unknown','범위 미확인'],['common','보통주'],['company','회사 전체'],['preferred','우선주']];
function addReturnItem(kind, value = {}) {
  const block = document.createElement('fieldset');
  block.className = 'return-item return-fields';
  block.append(field('적용 연도','year', value.year ?? returnReviewYear, 'number'));
  block.append(field('주식 범위','scope', value.scope, 'text', returnScopes));
  if (kind === 'event') {
    block.append(field('소각예정금액(억원)','amount', value.amount,'number'));
    block.append(field('소각예정일','cancellation_date',value.cancellation_date,'date'));
    block.append(field('연간 목표 외 추가 소각 확인','outside_policy',value.outside_policy,'checkbox'));
  } else {
    block.append(field('정책 종류','kind',value.kind,'text', [['cancellation','연간 소각 금액'],['total_amount','총환원 금액'],['total_ratio','총환원율'],['none','소각 계획 없음 확인']]));
    block.append(field('목표 금액(억원)','amount',value.amount,'number'));
    block.append(field('목표 환원율(0.5 = 50%)','ratio',value.ratio,'number'));
    block.append(field('회사의 소각 방침 확인','cancellation_commitment',value.cancellation_commitment,'checkbox'));
    block.append(field('목표 이익 기준','income_basis',value.income_basis ?? 'unknown','text', [['unknown','직접 확인 필요'],['net_income','수집된 당기순이익'],['owner_net_income','지배주주 순이익'],['adjusted','조정 이익 · 직접 보완']]));
    block.append(field('동일 기준 예상 이익 보완(억원)','income_amount',value.income_amount,'number'));
    block.append(field('동일 범위 예상 배당총액 보완(억원)','dividend_amount',value.dividend_amount,'number'));
  }
  block.append(field('금액·범위·가정의 근거','evidence',value.evidence,'textarea'));
  const remove = document.createElement('button'); remove.type = 'button'; remove.textContent = '항목 삭제';
  remove.addEventListener('click', () => block.remove()); block.append(remove);
  $return(kind + '-fields').append(block);
}

function editReturnDocument(doc = null) {
  editingReturnDocument = doc;
  $return('review-section').hidden = false;
  const form = $return('review-form'); form.reset();
  for (const name of ['ticker','title','source_url','published_at']) form.elements[name].value = doc?.[name] ?? '';
  form.elements.review_evidence.value = doc?.evidence ?? '';
  form.elements.ticker.readOnly = !!doc;
  form.elements.is_withdrawal.checked = !!doc?.is_withdrawal;
  const parent = form.elements.supersedes_id; parent.replaceChildren(new Option('없음',''));
  for (const other of returnDocuments) if (other.id !== doc?.id) parent.add(new Option(`${other.ticker} · #${other.id} ${other.title}`,other.id));
  parent.value = doc?.supersedes_id ?? '';
  $return('event-fields').replaceChildren(); $return('policy-fields').replaceChildren();
  for (const item of doc?.events ?? []) addReturnItem('event', item);
  for (const item of doc?.policies ?? []) addReturnItem('policy', item);
  $return('audit-output').textContent = '';
  $return('show-audit').disabled = !doc;
  $return('review-section').scrollIntoView({behavior:'smooth'});
}

function renderReturnDocuments() {
  const state = $return('status-filter').value;
  const period = $return('period-filter').value || 'current';
  const byId = new Map(returnDocuments.map(doc => [doc.id,doc]));
  const yearsById = new Map(returnDocuments.map(doc => [doc.id,returnDocumentYears(doc,byId)]));
  const tbody = $return('document-list'); tbody.replaceChildren();
  const periodDocuments = returnDocuments.filter(doc => matchesReturnPeriod(yearsById.get(doc.id),period));
  const shown = periodDocuments.filter(d => state === 'all' || (state === 'active' ? ['active','approved'].includes(d.status) : state === 'reference' ? ['reference','pending'].includes(d.status) : d.status === state));
  const labels = {current:`${returnReviewYear}·${returnReviewYear+1}년 대상`,history:`과거 이력 (${returnReviewYear-1}년 이전)`,unknown:'적용 연도 미확인',all:'전체 연도'};
  $return('document-status').textContent = `표시 ${shown.length.toLocaleString('ko-KR')}개 · ${labels[period]} ${periodDocuments.length.toLocaleString('ko-KR')}개 · 전체 ${returnDocuments.length.toLocaleString('ko-KR')}개`;
  if (!shown.length) {
    const row = document.createElement('tr'); const td = document.createElement('td'); td.colSpan = 6;
    td.textContent = returnDocuments.length ? '선택한 조건의 검토 자료가 없습니다. 자료 구분 또는 표시 상태를 변경하세요.' : '아직 수집된 검토 자료가 없습니다.';
    row.append(td); tbody.append(row);
  }
  for (const doc of shown) {
    const row = document.createElement('tr');
    for (const text of [doc.ticker,doc.title, yearsById.get(doc.id).join(' · ') || '미확인', {active:'자동 반영',reference:'근거만 보관',pending:'근거만 보관',approved:'반영 중',excluded:'반영 취소'}[doc.status],doc.error || '수집 완료']) {
      const td = document.createElement('td'); td.textContent = text; row.append(td);
    }
    const td = document.createElement('td'); const button = document.createElement('button'); button.textContent = '근거·수정';
    button.addEventListener('click', () => editReturnDocument(doc)); td.append(button); row.append(td); tbody.append(row);
    const toggle = document.createElement('button'); toggle.textContent = doc.status === 'excluded' ? '다시 반영' : '반영 취소';
    toggle.addEventListener('click', async () => {
      toggle.disabled = true;
      try {
        await setReturnSourceStatus(doc.id, doc.status === 'excluded' ? 'restore' : 'cancel');
        await loadReturnAdmin();
        adminMessage(doc.status === 'excluded' ? '다시 반영했습니다.' : '계산에서 제외했습니다. 원본과 변경 이력은 보존되며 다시 반영할 수 있습니다.');
      } catch (error) { adminMessage(error.message); toggle.disabled = false; }
    }); td.append(toggle);
  }
}

async function loadReturnDocuments() {
  $return('document-status').textContent = '검토 자료를 불러오는 중입니다…';
  try {
    returnDocuments = await returnAdminRequest('documents');
    renderReturnDocuments();
  } catch (error) {
    $return('document-status').textContent = '검토 자료를 불러오지 못했습니다. ' + error.message;
    throw error;
  }
}

async function loadReturnSources() {
  let sources;
  try { sources = await returnAdminRequest('sources'); }
  catch (error) { $return('source-list').textContent = 'IR 출처를 불러오지 못했습니다. ' + error.message; throw error; }
  $return('source-list').replaceChildren();
  for (const source of sources) {
    const p = document.createElement('p');
    p.textContent = `${source.ticker} · ${source.url} · ${source.enabled ? '수집 사용' : '수집 중지'} · ${source.error || (source.last_success_at ? '최근 수집 ' + source.last_success_at : '아직 수집되지 않음')}`;
    const button = document.createElement('button'); button.textContent = '수정';
    button.addEventListener('click', () => {
      const f = $return('source-form');
      for (const name of ['ticker','url','is_index','enabled']) f.elements[name].value = String(source[name]);
    }); p.append(button); $return('source-list').append(p);
  }
}

async function loadReturnAdmin() {
  const results = await Promise.allSettled([loadReturnDocuments(), loadReturnSources()]);
  const errors = results.filter(r => r.status === 'rejected').map(r => r.reason.message);
  if (errors.length) throw new Error([...new Set(errors)].join(' · '));
}

function readReturnItems(kind) {
  return [...$return(kind + '-fields').children].map(block => {
    const item = {};
    for (const input of block.querySelectorAll('input,select,textarea')) {
      item[input.name] = input.type === 'checkbox' ? input.checked : input.type === 'number' ? (input.value === '' ? null : Number(input.value)) : input.value;
    }
    if (kind === 'event' && !item.cancellation_date) item.cancellation_date = null;
    return item;
  });
}

$return('review-form').addEventListener('submit', async event => {
  event.preventDefault();
  const form = event.currentTarget;
  const payload = {ticker:form.elements.ticker.value, title:form.elements.title.value,
    source_key:editingReturnDocument?.source_key ?? 'manual:' + crypto.randomUUID(),
    source_url:form.elements.source_url.value, published_at:form.elements.published_at.value || null,
    evidence:form.elements.review_evidence.value, status:event.submitter?.value || 'active',
    supersedes_id:form.elements.supersedes_id.value ? Number(form.elements.supersedes_id.value) : null,
    is_withdrawal:form.elements.is_withdrawal.checked, events:readReturnItems('event'), policies:readReturnItems('policy')};
  const buttons = [...form.querySelectorAll('button')]; buttons.forEach(b => b.disabled = true);
  try {
    const saved = await returnAdminRequest('documents' + (editingReturnDocument ? '/' + editingReturnDocument.id : ''),
      {method:editingReturnDocument ? 'PUT':'POST',headers:{'Content-Type':'application/json'},body:JSON.stringify(payload)});
    await loadReturnAdmin(); editReturnDocument(saved); adminMessage('저장했습니다. 반영 중인 자료는 스크리너에 즉시 적용됩니다.');
  } catch (error) { adminMessage(error.message); }
  finally { buttons.forEach(b => b.disabled = false); }
});
$return('source-form').addEventListener('submit', async event => {
  event.preventDefault(); const form = event.currentTarget;
  try {
    await returnAdminRequest('sources', {method:'POST',headers:{'Content-Type':'application/json'},body:JSON.stringify({
      ticker:form.elements.ticker.value,url:form.elements.url.value,is_index:form.elements.is_index.value === 'true',enabled:form.elements.enabled.value === 'true'})});
    await loadReturnAdmin(); adminMessage('IR 출처를 저장했습니다. 다음 수집 실행부터 적용됩니다.');
  } catch (error) { adminMessage(error.message); }
});
$return('new-document').addEventListener('click', () => editReturnDocument());
$return('add-event').addEventListener('click', () => addReturnItem('event'));
$return('add-policy').addEventListener('click', () => addReturnItem('policy'));
$return('status-filter').addEventListener('change', renderReturnDocuments);
$return('period-filter').addEventListener('change', () => {
  const period = $return('period-filter').value;
  // History includes approved/excluded records; current work defaults to pending.
  $return('status-filter').value = period === 'history' || period === 'all' ? 'all' : period === 'unknown' ? 'reference' : 'active';
  renderReturnDocuments();
});
$return('period-current-label').textContent = `올해·내년 (${returnReviewYear}·${returnReviewYear+1}년)`;
$return('period-history-label').textContent = `과거 이력 (${returnReviewYear-1}년 이전)`;
$return('show-audit').addEventListener('click', async () => {
  try { $return('audit-output').textContent = JSON.stringify(await returnAdminRequest(`documents/${editingReturnDocument.id}/audit`),null,2); }
  catch (error) { adminMessage(error.message); }
});
loadReturnAdmin().catch(error => adminMessage(error.message));