import { useEffect, useState } from 'react';
import type { FormEvent } from 'react';
import { Link, useSearchParams } from 'react-router';
import { Alert, EmptyState, LoadingBlock, errorMessage } from '../components/Feedback';
import { Icon } from '../components/Icon';
import { useOperationalContext } from '../context/OperationalContext';
import { DocumentCenterTabs } from '../features/documents/DocumentCenterTabs';
import { OperationalFilters } from '../features/inspections/OperationalFilters';
import {
  listInspectionReportsF4,
  listPendingInspectionReportsF4,
} from '../lib/reportWorkflowApi';
import type {
  InspectionReportDetailF4,
  PageMetaF4,
  PendingInspectionReportF4,
} from '../lib/reportWorkflowApi';
import { formatDate } from '../lib/format';

function contextLabel(items: Array<{ name: string }>, empty: string): string {
  if (items.length === 0) return empty;
  const first = items[0];
  if (!first) return empty;
  if (items.length === 1) return first.name;
  return `${first.name} +${items.length - 1}`;
}

function statusLabel(report: InspectionReportDetailF4): string {
  if (report.status === 'OFFICIALIZED') return report.gedoIfIdentifier ? `GEDO · ${report.gedoIfIdentifier}` : 'Oficializado en GEDO';
  if (report.status === 'WORKING') return 'En preparación';
  if (report.status === 'CANCELLED') return 'Cancelado';
  return 'Legado congelado';
}

function statusClass(report: InspectionReportDetailF4): string {
  if (report.status === 'OFFICIALIZED') return 'active';
  if (report.status === 'CANCELLED') return 'danger';
  return 'pending';
}

export function ReportsPage() {
  const [params, setParams] = useSearchParams();
  const operationalContext = useOperationalContext();
  const view = params.get('view') === 'pending' ? 'pending' : 'issued';
  const search = params.get('search') ?? '';
  const year = params.get('year') ?? '';
  const companyId = operationalContext.companyId || params.get('companyId') || '';
  const areaId = operationalContext.areaId || params.get('areaId') || '';
  const inspectorId = params.get('inspectorId') ?? '';
  const dateFrom = params.get('dateFrom') ?? '';
  const dateTo = params.get('dateTo') ?? '';
  const page = Math.max(1, Number(params.get('page') ?? 1) || 1);
  const [draftSearch, setDraftSearch] = useState(search);
  const [issued, setIssued] = useState<InspectionReportDetailF4[]>([]);
  const [pending, setPending] = useState<PendingInspectionReportF4[]>([]);
  const [meta, setMeta] = useState<PageMetaF4>({ page: 1, pageSize: 25, total: 0, totalPages: 0 });
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState('');

  useEffect(() => {
    let cancelled = false;
    setLoading(true);
    setError('');
    const query = {
      page,
      pageSize: 25,
      search,
      year: year ? Number(year) : undefined,
      companyId,
      areaId,
      inspectorId,
      dateFrom,
      dateTo,
    };
    const load = async () => {
      try {
        if (view === 'issued') {
          const response = await listInspectionReportsF4(query);
          if (cancelled) return;
          setIssued(response.data);
          setPending([]);
          setMeta(response.meta);
        } else {
          const response = await listPendingInspectionReportsF4(query);
          if (cancelled) return;
          setPending(response.data);
          setIssued([]);
          setMeta(response.meta);
        }
      } catch (requestError) {
        if (!cancelled) setError(errorMessage(requestError));
      } finally {
        if (!cancelled) setLoading(false);
      }
    };
    void load();
    return () => { cancelled = true; };
  }, [page, search, view, year, companyId, areaId, inspectorId, dateFrom, dateTo]);

  const setFilter = (key: string, value: string) => {
    const next = new URLSearchParams(params);
    if (key === 'areaId') {
      operationalContext.setAreaId(value);
      next.delete('areaId');
      next.delete('companyId');
    } else if (key === 'companyId') {
      operationalContext.setCompanyId(value);
      next.delete('companyId');
    } else {
      value ? next.set(key, value) : next.delete(key);
    }
    next.delete('page');
    setParams(next);
  };

  const applySearch = (event: FormEvent) => {
    event.preventDefault();
    setFilter('search', draftSearch.trim());
  };

  const setPage = (value: number) => {
    const next = new URLSearchParams(params);
    value > 1 ? next.set('page', String(value)) : next.delete('page');
    setParams(next);
  };

  const empty = view === 'issued' ? issued.length === 0 : pending.length === 0;

  return <section>
    <div className="page-heading">
      <div><span className="eyebrow">CENTRO DOCUMENTAL</span><h1>Informes</h1><p>Cada Acta sellada genera un único INF editable. Luego el IF y PDF oficial de GEDO completan su trazabilidad institucional.</p></div>
    </div>
    <DocumentCenterTabs />

    <div className="document-view-tabs">
      <button type="button" className={view === 'issued' ? 'active' : ''} onClick={() => setFilter('view', 'issued')}>Informes</button>
      <button type="button" className={view === 'pending' ? 'active' : ''} onClick={() => setFilter('view', 'pending')}>Actas selladas sin INF</button>
    </div>

    <form className="toolbar survey-toolbar" onSubmit={applySearch}>
      <label className="search-field"><Icon name="search" /><input value={draftSearch} onChange={(event) => setDraftSearch(event.target.value)} placeholder="Buscar INF, IF GEDO, acta, inspección, empresa o área" /><button>Buscar</button></label>
      <label className="select-field"><span>Año</span><input inputMode="numeric" value={year} onChange={(event) => setFilter('year', event.target.value.replace(/\D/g, '').slice(0, 4))} placeholder="Todos" /></label>
      <OperationalFilters inspectorId={inspectorId} dateFrom={dateFrom} dateTo={dateTo} onChange={setFilter} />
    </form>

    {view === 'pending' && <div className="temporal-notice"><Icon name="clipboard" /><p><strong>Actas listas para generar INF.</strong> Esta bandeja sólo muestra Actas selladas que todavía no tienen su Informe 1 a 1.</p></div>}
    {error && <Alert>{error}</Alert>}
    {loading ? <LoadingBlock label={view === 'issued' ? 'Cargando informes…' : 'Cargando actas pendientes…'} /> : empty ? <EmptyState title={view === 'issued' ? 'Sin informes' : 'Sin actas pendientes'} text={view === 'issued' ? 'Todavía no hay informes para los filtros seleccionados.' : 'Todas las Actas selladas tienen su INF correspondiente.'} /> : <div className="table-panel document-table">
      <div className="table-summary"><strong>{meta.total} {view === 'issued' ? `informe${meta.total === 1 ? '' : 's'}` : `acta${meta.total === 1 ? '' : 's'} pendiente${meta.total === 1 ? '' : 's'}`}</strong><span>Página {page} de {Math.max(meta.totalPages, 1)}</span></div>
      <div className="table-scroll"><table><thead>{view === 'issued' ? <tr><th>Informe</th><th>Empresa / área</th><th>Acta</th><th>Hallazgos</th><th>Word</th><th>Estado</th><th /></tr> : <tr><th>Acta sellada</th><th>Empresa / área</th><th>Inspección</th><th>Hallazgos</th><th>Sellado</th><th /></tr>}</thead><tbody>{view === 'issued' ? issued.map((report) => <tr key={report.id}>
        <td><div className="document-primary"><strong>{report.code}</strong><small>{report.title} · {formatDate(report.generatedAt)}</small></div></td>
        <td><div className="document-primary"><strong>{contextLabel(report.companies, 'Empresa sin asignar')}</strong><small>{contextLabel(report.areas, 'Área sin asignar')}</small></div></td>
        <td><Link className="text-link" to={`/inspecciones/actas/${report.actId}`}>{report.act.code}<small className="block-muted">{report.act.title}</small></Link></td>
        <td><Link className="text-link" to={`/hallazgos?search=${encodeURIComponent(report.act.code)}`}>{report.findingCount}</Link></td>
        <td><span className={`status-badge ${report.wordStatus === 'READY' ? 'active' : report.wordStatus === 'FAILED' ? 'danger' : 'pending'}`}>{report.wordStatus === 'READY' ? 'Disponible' : report.wordStatus === 'FAILED' ? 'Error' : 'Pendiente'}</span></td>
        <td><span className={`status-badge ${statusClass(report)}`}>{statusLabel(report)}</span></td>
        <td className="action-cell"><Link className="icon-button" to={`/informes/${report.id}`} aria-label={`Abrir ${report.code}`}><Icon name="chevron" /></Link></td>
      </tr>) : pending.map((item) => <tr key={item.actId}>
        <td><div className="document-primary"><strong>{item.actCode}</strong><small>{item.actTitle} · {formatDate(item.occurredAt)}</small></div></td>
        <td><div className="document-primary"><strong>{contextLabel(item.companies, 'Empresa sin asignar')}</strong><small>{contextLabel(item.areas, 'Área sin asignar')}</small></div></td>
        <td><Link className="text-link" to={`/inspecciones/${item.visitId}`}>{item.visitCode}</Link></td>
        <td><Link className="text-link" to={`/hallazgos?search=${encodeURIComponent(item.actCode)}`}>{item.findingCount}</Link></td>
        <td>{formatDate(item.sealedAt)}</td>
        <td className="action-cell"><Link className="icon-button" to={`/inspecciones/actas/${item.actId}`} aria-label={`Abrir ${item.actCode}`}><Icon name="chevron" /></Link></td>
      </tr>)}</tbody></table></div>
      <div className="pagination"><button className="button secondary" disabled={page <= 1} onClick={() => setPage(page - 1)}>Anterior</button><span>{meta.total ? `${(page - 1) * meta.pageSize + 1}–${Math.min(page * meta.pageSize, meta.total)} de ${meta.total}` : '0 resultados'}</span><button className="button secondary" disabled={page >= meta.totalPages} onClick={() => setPage(page + 1)}>Siguiente</button></div>
    </div>}
  </section>;
}