import { useCallback, useEffect, useMemo, useState } from 'react';
import { AlertTriangle, CheckCircle2, CloudDownload, Database, Link2, Loader2, RefreshCw, ScrollText, Square, Timer, X, XCircle } from 'lucide-react';
import { fetchOlistRunDetails, fetchOlistStatus, getOlistAuthorizationUrl, startOlistCompositionSync, stopOlistCompositionSync } from '../dataService';
import type { OlistRunDetails, OlistStatus, OlistSyncRun } from '../types';

const formatDateTime = (value: string | null) => {
  if (!value) return '—';
  const date = new Date(value);
  return Number.isNaN(date.getTime()) ? '—' : new Intl.DateTimeFormat('pt-BR', {
    dateStyle: 'short',
    timeStyle: 'medium'
  }).format(date);
};

const formatDuration = (startedAt: string | null, endedAt: string | null, now: number) => {
  if (!startedAt) return '—';
  const start = new Date(startedAt).getTime();
  const end = endedAt ? new Date(endedAt).getTime() : now;
  if (Number.isNaN(start) || Number.isNaN(end)) return '—';
  const totalSeconds = Math.max(0, Math.floor((end - start) / 1000));
  const hours = Math.floor(totalSeconds / 3600);
  const minutes = Math.floor((totalSeconds % 3600) / 60);
  const seconds = totalSeconds % 60;
  return hours ? `${hours}h ${minutes}m` : `${minutes}m ${seconds}s`;
};

const runTone = (run: OlistSyncRun) => (
  run.status === 'failed' ? 'text-red-300 border-red-400/30 bg-red-400/10'
    : run.status === 'running' ? 'text-sky-300 border-sky-400/30 bg-sky-400/10'
      : run.status === 'cancelled' ? 'text-amber-200 border-amber-400/30 bg-amber-400/10'
      : 'text-emerald-300 border-emerald-400/30 bg-emerald-400/10'
);

const runStatusLabel = (run: OlistSyncRun) => (
  run.status === 'running' ? (run.cancelRequestedAt ? 'Parando' : 'Em andamento')
    : run.status === 'failed' ? 'Falhou'
      : run.status === 'cancelled' ? 'Interrompida'
        : 'Concluída'
);

const OlistSync = () => {
  const [status, setStatus] = useState<OlistStatus | null>(null);
  const [isLoading, setIsLoading] = useState(true);
  const [isActionLoading, setIsActionLoading] = useState(false);
  const [error, setError] = useState('');
  const [now, setNow] = useState(0);
  const [selectedRunId, setSelectedRunId] = useState<number | null>(null);
  const [runDetails, setRunDetails] = useState<OlistRunDetails | null>(null);
  const [detailsPages, setDetailsPages] = useState({ events: 1, products: 1 });
  const [isDetailsLoading, setIsDetailsLoading] = useState(false);

  const loadStatus = useCallback(async (initial = false) => {
    if (initial) setIsLoading(true);
    try {
      setStatus(await fetchOlistStatus());
      setError('');
    } catch (loadError) {
      setError(loadError instanceof Error ? loadError.message : 'Não foi possível consultar a Olist.');
    } finally {
      if (initial) setIsLoading(false);
    }
  }, []);

  useEffect(() => {
    const loadTimeout = window.setTimeout(() => void loadStatus(true), 0);
    const pollInterval = window.setInterval(() => void loadStatus(), 5_000);
    const clockInterval = window.setInterval(() => setNow(Date.now()), 1_000);
    return () => {
      window.clearTimeout(loadTimeout);
      window.clearInterval(pollInterval);
      window.clearInterval(clockInterval);
    };
  }, [loadStatus]);

  const loadRunDetails = useCallback(async (runId: number, pages: { events: number; products: number }) => {
    setIsDetailsLoading(true);
    try {
      setRunDetails(await fetchOlistRunDetails(runId, pages.events, pages.products));
    } catch (loadError) {
      setError(loadError instanceof Error ? loadError.message : 'Não foi possível consultar os detalhes da execução.');
    } finally {
      setIsDetailsLoading(false);
    }
  }, []);

  useEffect(() => {
    if (!selectedRunId || runDetails?.run.status !== 'running') return;
    const intervalId = window.setInterval(() => void loadRunDetails(selectedRunId, detailsPages), 5_000);
    return () => window.clearInterval(intervalId);
  }, [selectedRunId, runDetails?.run.status, detailsPages, loadRunDetails]);

  const latestRun = status?.runs[0] || null;
  const completionPercent = useMemo(() => {
    const cache = status?.productCache;
    if (!cache?.total) return 0;
    return Math.round((cache.checked / cache.total) * 100);
  }, [status?.productCache]);

  const connect = async () => {
    setIsActionLoading(true);
    try {
      window.location.assign(await getOlistAuthorizationUrl());
    } catch (actionError) {
      setError(actionError instanceof Error ? actionError.message : 'Não foi possível iniciar a conexão Olist.');
      setIsActionLoading(false);
    }
  };

  const startSync = async () => {
    setIsActionLoading(true);
    try {
      await startOlistCompositionSync(!status?.runs.some(run => run.status === 'completed'));
      await loadStatus();
    } catch (actionError) {
      setError(actionError instanceof Error ? actionError.message : 'Não foi possível iniciar a sincronização.');
    } finally {
      setIsActionLoading(false);
    }
  };

  const stopSync = async () => {
    if (!window.confirm('Interromper a sincronização atual? Os produtos já concluídos serão preservados e a próxima sincronização continuará de onde parou.')) return;
    setIsActionLoading(true);
    try {
      await stopOlistCompositionSync();
      await loadStatus();
    } catch (actionError) {
      setError(actionError instanceof Error ? actionError.message : 'Não foi possível interromper a sincronização.');
    } finally {
      setIsActionLoading(false);
    }
  };

  const openRunDetails = (runId: number) => {
    const initialPages = { events: 1, products: 1 };
    setDetailsPages(initialPages);
    setSelectedRunId(runId);
    void loadRunDetails(runId, initialPages);
  };

  if (isLoading && !status) {
    return <div className="flex h-64 items-center justify-center rounded-2xl border border-dark-border bg-dark-card text-brand-primary"><Loader2 className="h-7 w-7 animate-spin" /></div>;
  }

  return (
    <div className="space-y-6">
      <div className="flex flex-col gap-4 xl:flex-row xl:items-start xl:justify-between">
        <div>
          <h1 className="text-2xl font-bold text-dark-text">Olist</h1>
          <p className="mt-2 font-medium text-dark-muted">Monitoramento da conexão e da sincronização de composições.</p>
        </div>
        <div className="flex flex-wrap gap-2">
          <button type="button" onClick={() => void loadStatus()} className="inline-flex h-10 items-center gap-2 rounded-xl border border-dark-border bg-dark-card px-4 text-sm font-bold text-dark-text transition-colors hover:border-brand-primary cursor-pointer">
            <RefreshCw className="h-4 w-4" /> Atualizar
          </button>
          {!status?.connected ? (
            <button type="button" onClick={() => void connect()} disabled={!status?.configured || isActionLoading} className="inline-flex h-10 items-center gap-2 rounded-xl bg-brand-primary px-4 text-sm font-bold text-brand-contrast transition-colors hover:bg-brand-primary/90 disabled:cursor-not-allowed disabled:opacity-50 cursor-pointer">
              {isActionLoading ? <Loader2 className="h-4 w-4 animate-spin" /> : <Link2 className="h-4 w-4" />} Conectar Olist
            </button>
          ) : (
            <>
              <button type="button" onClick={() => void startSync()} disabled={isActionLoading || status.syncInProgress} className="inline-flex h-10 items-center gap-2 rounded-xl bg-brand-primary px-4 text-sm font-bold text-brand-contrast transition-colors hover:bg-brand-primary/90 disabled:cursor-not-allowed disabled:opacity-50 cursor-pointer">
                {isActionLoading || status.syncInProgress ? <Loader2 className="h-4 w-4 animate-spin" /> : <CloudDownload className="h-4 w-4" />} {status.syncInProgress ? 'Sincronizando' : 'Sincronizar agora'}
              </button>
              {status.syncInProgress && (
                <button type="button" onClick={() => void stopSync()} disabled={isActionLoading || Boolean(latestRun?.cancelRequestedAt)} title="Parar sincronização" aria-label="Parar sincronização" className="inline-flex h-10 w-10 items-center justify-center rounded-xl border border-red-400/30 bg-red-400/10 text-red-300 transition-colors hover:bg-red-400/20 disabled:cursor-not-allowed disabled:opacity-50 cursor-pointer">
                  <Square className="h-4 w-4 fill-current" />
                </button>
              )}
            </>
          )}
        </div>
      </div>

      {error && <div className="rounded-2xl border border-red-400/30 bg-red-400/10 px-4 py-3 text-sm font-bold text-red-300">{error}</div>}
      {!status?.configured && <div className="rounded-2xl border border-amber-400/30 bg-amber-400/10 px-4 py-3 text-sm font-bold text-amber-200">Configure as credenciais Olist V3 no ambiente antes de conectar.</div>}

      <div className="grid grid-cols-1 gap-4 md:grid-cols-3">
        <div className="rounded-2xl border border-dark-border bg-dark-card p-5">
          <div className="flex items-center justify-between"><span className="text-xs font-bold uppercase tracking-widest text-dark-muted">Conexão</span><Link2 className="h-4 w-4 text-brand-primary" /></div>
          <p className={`mt-4 text-lg font-bold ${status?.connected ? 'text-emerald-300' : 'text-dark-text'}`}>{status?.connected ? 'Conectada' : 'Não conectada'}</p>
          <p className="mt-1 text-xs font-semibold text-dark-muted">Token expira: {formatDateTime(status?.tokenExpiresAt || null)}</p>
        </div>
        <div className="rounded-2xl border border-dark-border bg-dark-card p-5">
          <div className="flex items-center justify-between"><span className="text-xs font-bold uppercase tracking-widest text-dark-muted">Execução atual</span><Timer className="h-4 w-4 text-brand-primary" /></div>
          <p className="mt-4 text-lg font-bold text-dark-text">{latestRun?.status === 'running' ? (latestRun.cancelRequestedAt ? 'Parando' : 'Em andamento') : 'Em espera'}</p>
          <p className="mt-1 text-xs font-semibold text-dark-muted">{latestRun?.status === 'running' ? `Duração: ${formatDuration(latestRun.startedAt, null, now)}` : `Próxima automática: ${formatDateTime(status?.nextScheduledSyncAt || null)}`}</p>
        </div>
        <div className="rounded-2xl border border-dark-border bg-dark-card p-5">
          <div className="flex items-center justify-between"><span className="text-xs font-bold uppercase tracking-widest text-dark-muted">Estruturas</span><Database className="h-4 w-4 text-brand-primary" /></div>
          <p className="mt-4 text-lg font-bold text-dark-text">{status?.productCache.checked.toLocaleString('pt-BR') || 0} / {status?.productCache.total.toLocaleString('pt-BR') || 0}</p>
          <p className="mt-1 text-xs font-semibold text-dark-muted">{completionPercent}% verificadas · {status?.productCache.pending || 0} pendentes</p>
        </div>
      </div>

      {latestRun && (
        <div className="rounded-2xl border border-dark-border bg-dark-card p-5">
          <div className="flex flex-col gap-3 sm:flex-row sm:items-center sm:justify-between">
            <div>
              <h2 className="text-sm font-bold text-dark-text">Última execução</h2>
              <p className="mt-1 text-xs font-semibold text-dark-muted">Início: {formatDateTime(latestRun.startedAt)} · {latestRun.mode === 'full' ? 'Carga completa' : 'Atualização incremental'}</p>
            </div>
            <span className={`inline-flex w-fit items-center gap-2 rounded-full border px-3 py-1 text-xs font-bold ${runTone(latestRun)}`}>
              {latestRun.status === 'failed' ? <XCircle className="h-3.5 w-3.5" /> : latestRun.status === 'running' ? <Loader2 className="h-3.5 w-3.5 animate-spin" /> : latestRun.status === 'cancelled' ? <Square className="h-3.5 w-3.5 fill-current" /> : <CheckCircle2 className="h-3.5 w-3.5" />}
              {runStatusLabel(latestRun)}
            </span>
          </div>
          <div className="mt-5 grid grid-cols-2 gap-3 sm:grid-cols-4 lg:grid-cols-6">
            {[
              ['Produtos verificados', latestRun.productsScanned],
              ['Fabricados', latestRun.manufacturedProducts],
              ['Composições', latestRun.imported],
              ['Componentes', latestRun.componentCount],
              ['Referências', latestRun.referenceCount],
              ['Falhas', latestRun.failed]
            ].map(([label, value]) => <div key={String(label)} className="rounded-xl border border-dark-border bg-dark-input/50 p-3"><p className="text-[10px] font-bold uppercase tracking-widest text-dark-muted">{label}</p><p className={`mt-2 text-lg font-bold ${label === 'Falhas' && Number(value) ? 'text-red-300' : 'text-dark-text'}`}>{Number(value).toLocaleString('pt-BR')}</p></div>)}
          </div>
          {latestRun.errorMessage && <p className="mt-4 rounded-xl border border-red-400/30 bg-red-400/10 p-3 text-sm font-semibold text-red-300">{latestRun.errorMessage}</p>}
          {latestRun.details.length > 0 && <div className="mt-4 rounded-xl border border-amber-400/25 bg-amber-400/5 p-3 text-xs font-semibold text-amber-100"><div className="mb-2 flex items-center gap-2"><AlertTriangle className="h-4 w-4" /> Produtos com falha</div>{latestRun.details.slice(0, 5).map((detail, index) => <p key={`${detail.productId || index}-${detail.sku || ''}`}>{detail.sku || detail.productId}: {detail.error || 'Falha sem detalhe'}</p>)}</div>}
          <button type="button" onClick={() => openRunDetails(latestRun.id)} className="mt-4 inline-flex h-9 items-center gap-2 rounded-lg border border-dark-border px-3 text-xs font-bold text-dark-text transition-colors hover:border-brand-primary cursor-pointer"><ScrollText className="h-4 w-4 text-brand-primary" /> Ver logs e produtos</button>
        </div>
      )}

      <div className="overflow-hidden rounded-2xl border border-dark-border bg-dark-card">
        <div className="border-b border-dark-border p-5"><h2 className="text-sm font-bold text-dark-text">Histórico de sincronizações</h2></div>
        <div className="divide-y divide-dark-border">
          {!status?.runs.length && <div className="p-8 text-center text-sm font-semibold text-dark-muted">Nenhuma sincronização iniciada.</div>}
          {status?.runs.map(run => <div key={run.id} className="flex flex-col gap-3 p-4 md:flex-row md:items-center md:justify-between"><div><p className="text-sm font-bold text-dark-text">{run.mode === 'full' ? 'Carga completa' : 'Atualização incremental'} · {run.trigger === 'scheduled' ? 'Automática' : 'Manual'}</p><p className="mt-1 text-xs font-semibold text-dark-muted">{formatDateTime(run.startedAt)} · duração {formatDuration(run.startedAt, run.status === 'running' ? null : run.completedAt, now)}</p></div><div className="flex flex-wrap items-center gap-3 text-xs font-bold text-dark-muted"><span>{run.imported} comp.</span><span>{run.referenceCount} refs.</span><span className={run.failed ? 'text-red-300' : ''}>{run.failed} falhas</span><span className={`rounded-full border px-2.5 py-1 ${runTone(run)}`}>{runStatusLabel(run)}</span><button type="button" onClick={() => openRunDetails(run.id)} title="Ver logs e produtos afetados" aria-label="Ver logs e produtos afetados" className="inline-flex h-8 w-8 items-center justify-center rounded-lg border border-dark-border text-brand-primary transition-colors hover:border-brand-primary cursor-pointer"><ScrollText className="h-4 w-4" /></button></div></div>)}
        </div>
      </div>

      {selectedRunId && (
        <div className="fixed inset-0 z-50 flex items-end justify-center bg-black/70 p-0 backdrop-blur-sm sm:items-center sm:p-6" role="dialog" aria-modal="true" aria-label="Logs e produtos afetados da sincronização Olist">
          <div className="max-h-[92vh] w-full max-w-6xl overflow-y-auto rounded-t-2xl border border-dark-border bg-dark-card shadow-2xl sm:rounded-2xl">
            <div className="sticky top-0 z-10 flex items-start justify-between border-b border-dark-border bg-dark-card p-5">
              <div>
                <h2 className="text-base font-bold text-dark-text">Logs e produtos afetados</h2>
                <p className="mt-1 text-xs font-semibold text-dark-muted">{runDetails ? `${runDetails.run.mode === 'full' ? 'Carga completa' : 'Atualização incremental'} · ${formatDateTime(runDetails.run.startedAt)}` : 'Carregando execução...'}</p>
              </div>
              <button type="button" onClick={() => { setSelectedRunId(null); setRunDetails(null); }} title="Fechar" aria-label="Fechar" className="inline-flex h-9 w-9 items-center justify-center rounded-lg border border-dark-border text-dark-muted transition-colors hover:border-brand-primary hover:text-dark-text cursor-pointer"><X className="h-4 w-4" /></button>
            </div>
            {isDetailsLoading && !runDetails ? (
              <div className="flex h-56 items-center justify-center"><Loader2 className="h-6 w-6 animate-spin text-brand-primary" /></div>
            ) : runDetails ? (
              <div className="grid gap-5 p-5 lg:grid-cols-2">
                <section className="overflow-hidden rounded-xl border border-dark-border">
                  <div className="flex items-center justify-between border-b border-dark-border px-4 py-3"><div><h3 className="text-sm font-bold text-dark-text">Logs</h3><p className="mt-0.5 text-xs font-semibold text-dark-muted">{runDetails.events.total.toLocaleString('pt-BR')} eventos</p></div>{isDetailsLoading && <Loader2 className="h-4 w-4 animate-spin text-brand-primary" />}</div>
                  <div className="divide-y divide-dark-border">
                    {!runDetails.events.items.length && <p className="p-5 text-sm font-semibold text-dark-muted">Nenhum evento registrado ainda.</p>}
                    {runDetails.events.items.map(event => <div key={event.id} className="p-4"><div className="flex items-start gap-2"><span className={`mt-1.5 h-2 w-2 shrink-0 rounded-full ${event.level === 'error' ? 'bg-red-400' : 'bg-sky-400'}`} /><div className="min-w-0"><p className="text-sm font-semibold text-dark-text">{event.message}</p>{event.sku && <p className="mt-1 truncate text-xs font-bold text-brand-primary">{event.sku} · {event.productDescription}</p>}<p className="mt-1 text-[11px] font-semibold text-dark-muted">{formatDateTime(event.createdAt)}</p></div></div></div>)}
                  </div>
                  <div className="flex items-center justify-between border-t border-dark-border p-3"><button type="button" onClick={() => { const pages = { ...detailsPages, events: Math.max(1, detailsPages.events - 1) }; setDetailsPages(pages); void loadRunDetails(runDetails.run.id, pages); }} disabled={runDetails.events.page === 1 || isDetailsLoading} className="text-xs font-bold text-dark-muted disabled:opacity-40 cursor-pointer">Anterior</button><span className="text-xs font-semibold text-dark-muted">Página {runDetails.events.page}</span><button type="button" onClick={() => { const pages = { ...detailsPages, events: detailsPages.events + 1 }; setDetailsPages(pages); void loadRunDetails(runDetails.run.id, pages); }} disabled={runDetails.events.page * runDetails.events.pageSize >= runDetails.events.total || isDetailsLoading} className="text-xs font-bold text-brand-primary disabled:opacity-40 cursor-pointer">Próxima</button></div>
                </section>
                <section className="overflow-hidden rounded-xl border border-dark-border">
                  <div className="border-b border-dark-border px-4 py-3"><h3 className="text-sm font-bold text-dark-text">Produtos afetados</h3><p className="mt-0.5 text-xs font-semibold text-dark-muted">{runDetails.affectedProducts.total.toLocaleString('pt-BR')} composições importadas nesta execução</p></div>
                  <div className="divide-y divide-dark-border">
                    {!runDetails.affectedProducts.items.length && <p className="p-5 text-sm font-semibold text-dark-muted">Nenhuma composição importada nesta execução.</p>}
                    {runDetails.affectedProducts.items.map(product => <div key={product.id} className="p-4"><p className="text-sm font-bold text-dark-text">{product.productDescription || product.sku || product.productId}</p><p className="mt-1 text-xs font-semibold text-brand-primary">{product.sku || `ID ${product.productId}`}</p><p className="mt-2 text-xs font-semibold text-dark-muted">{Number(product.metadata.componentCount || 0).toLocaleString('pt-BR')} componentes · {Number(product.metadata.referenceCount || 0).toLocaleString('pt-BR')} referências</p></div>)}
                  </div>
                  <div className="flex items-center justify-between border-t border-dark-border p-3"><button type="button" onClick={() => { const pages = { ...detailsPages, products: Math.max(1, detailsPages.products - 1) }; setDetailsPages(pages); void loadRunDetails(runDetails.run.id, pages); }} disabled={runDetails.affectedProducts.page === 1 || isDetailsLoading} className="text-xs font-bold text-dark-muted disabled:opacity-40 cursor-pointer">Anterior</button><span className="text-xs font-semibold text-dark-muted">Página {runDetails.affectedProducts.page}</span><button type="button" onClick={() => { const pages = { ...detailsPages, products: detailsPages.products + 1 }; setDetailsPages(pages); void loadRunDetails(runDetails.run.id, pages); }} disabled={runDetails.affectedProducts.page * runDetails.affectedProducts.pageSize >= runDetails.affectedProducts.total || isDetailsLoading} className="text-xs font-bold text-brand-primary disabled:opacity-40 cursor-pointer">Próxima</button></div>
                </section>
              </div>
            ) : <div className="p-8 text-center text-sm font-semibold text-dark-muted">Não foi possível carregar os detalhes desta execução.</div>}
          </div>
        </div>
      )}
    </div>
  );
};

export default OlistSync;