feat: skeletons where the page waits, no flicker while a sheet is read, repeated copies in the preview

Reading a large sheet repainted the list and "Sua folha" on every progress
step, so the preview flickered; progress now moves the bar in place and
"Sua folha" shows a skeleton until the preview is ready. A sheet printed
N times is shown N times (up to six, then a count). The payment page shows
skeletons while the order loads and until the card form is ready.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/checkout.js

@@ -86,6 +86,11 @@
     rows.push(linha('Total', rs(approved.total_cents/100), 'tot'));
     resumo.replaceChildren(node('h4','Resumo do pedido'), ...rows);
   }
+  function esqueletoPagamento() {
+    const linhas=['skel skelLinha','skel skelLinha','skel skelLinha curta'].map(c=>node('div',null,c));
+    resumo.hidden=false; resumo.replaceChildren(node('h4','Resumo do pedido'),...linhas);
+    actions.replaceChildren(node('div',null,'skel skelLinha curta'),node('div',null,'skel skelBloco'));
+  }
   function semPedido() {
     pintaResumo(null);
     actions.replaceChildren();
@@ -259,6 +264,7 @@
     if (!naPagina()) { if (!go || !draftId) return; }
     else if (!draftId) { semPedido(); return; }
     const version=++refreshVersion, shownId=draftId;
+    if (naPagina() && !actions.children.length) esqueletoPagamento();
     try {
       await ready;
       const quote=await api('/quotes/'+shownId);
@@ -474,9 +480,10 @@
   async function showCard(approved, into, version, tipo) {
     const holder=node('div');
     holder.id='cardPaymentBrick';
-    into.append(holder);
+    const espera=node('div',null,'skel skelBloco');
+    into.append(espera,holder);
     try { await loadMercadoPago(); }
-    catch(error) { message(error.message); return; }
+    catch(error) { espera.remove(); message(error.message); return; }
     const session=await ready;
     // The customer may have switched to PIX, or the page re-rendered, meanwhile.
     if (!holder.isConnected || version!==refreshVersion) return;
@@ -493,7 +500,7 @@
         visual:{hideFormTitle:true,
           style:{customVariables:{baseColor:'#FFA81A',buttonTextColor:'#03060B'}}}},
       callbacks:{
-        onReady:()=>{},
+        onReady:()=>{ espera.remove(); },
         onError:error=>{ console.error(error); message('Erro no formulário do cartão. Confira os dados e tente de novo.'); },
         onSubmit:async data=>{
           if (!cartOk()) { await refresh(); throw new Error('cart changed'); }

web/site-packing.js

@@ -277,16 +277,32 @@ function previaAoVivo(){
     const tot=folhaTotalM();
     $('vMt').textContent = tot>0 ? fmtM(cobrar(tot))+' m' : '—';
     const medidas=folhas.filter(x=>x.med);
-    const previews=folhas.filter(x=>x.previewSrc);
+    // Sheets still being read show a placeholder; a sheet printed N times is
+    // shown N times (up to REPETE_MAX, then a count).
+    const REPETE_MAX=6;
+    const previews=folhas.filter(x=>x.previewSrc || (x.pct!=null && x.med && x.med.grande));
     if(previews.length){
       const painel=document.createElement('div'); painel.className='folhaPrevias';
       previews.forEach((x,index)=>{
         const figura=document.createElement('figure'); figura.className='folhaPrevia';
-        const imagem=new Image(); imagem.src=x.previewSrc; imagem.alt=x.f.name;
         const legenda=document.createElement('figcaption');
+        const vezes=Math.max(1,x.rep||1);
         legenda.textContent=(previews.length>1 ? (index+1)+'. ' : '')+x.f.name+
-          (x.med ? ' · '+n1(x.med.larg)+' × '+n1(x.med.alt)+' cm' : '');
+          (x.med ? ' · '+n1(x.med.larg)+' × '+n1(x.med.alt)+' cm' : '')+(vezes>1 ? ' · '+vezes+' cópias' : '');
-        figura.append(imagem,legenda); painel.append(figura);
+        if(!x.previewSrc){
+          const esqueleto=document.createElement('div'); esqueleto.className='skel folhaSkel';
+          esqueleto.style.aspectRatio=x.med ? x.med.larg+' / '+Math.min(x.med.alt,x.med.larg*4) : '1 / 2';
+          esqueleto.append(Object.assign(document.createElement('span'),{textContent:'Gerando a prévia da folha…'}));
+          figura.append(esqueleto,legenda); painel.append(figura); return;
+        }
+        const pilha=document.createElement('div'); pilha.className='folhaPilha';
+        for(let k=0;k<Math.min(vezes,REPETE_MAX);k++){
+          const imagem=new Image(); imagem.src=x.previewSrc; imagem.alt=k? '' : x.f.name;
+          imagem.style.maxHeight=Math.floor(520/Math.min(vezes,REPETE_MAX))+'px'; pilha.append(imagem);
+        }
+        if(vezes>REPETE_MAX) pilha.append(Object.assign(document.createElement('div'),
+          {className:'folhaMais', textContent:'+ '+(vezes-REPETE_MAX)+' cópia'+(vezes-REPETE_MAX>1?'s':'')}));
+        figura.append(pilha,legenda); painel.append(figura);
       });
       $('vArea').replaceChildren(painel);
     }else{

web/site-pdf.js

@@ -352,6 +352,18 @@ function medirFolha(file){
   });
 }
 
+function textoProgresso(x){
+  if(x.med && x.med.grande) return 'gerando a prévia e conferindo a arte… '+x.pct+'%';
+  return x.pct<50?'lendo o arquivo…':x.pct<70?'medindo a folha…':'conferindo a arte…';
+}
+// Moves one sheet's progress bar in place: repainting the whole list and the
+// preview on every step made "Sua folha" flicker while a large file was read.
+function pintaProgressoFolha(x){
+  const el=$('lista').querySelector('.rep[data-folha="'+folhas.indexOf(x)+'"]');
+  const barra=el && el.querySelector('.prog i'), texto=el && el.querySelector('.progT');
+  if(!barra){ pintaFolha(); return; }
+  barra.style.width=x.pct+'%'; if(texto) texto.textContent=textoProgresso(x);
+}
 function pintaFolha(){
   invalidaItemAtual();
   const L=larguraFilme();
@@ -415,14 +427,13 @@ function pintaFolha(){
     }
     const barra = x.pct!=null
       ? '<div class="prog"><i style="width:'+x.pct+'%"></i></div>'+
-        '<span class="progT">'+(x.pct<50?'lendo o arquivo…':
+        '<span class="progT">'+textoProgresso(x)+'</span>'
-          x.pct<70?'medindo a folha…':'conferindo a arte…')+'</span>'
       : x.semAnalise
       ? '<div class="progF"><b>Não conseguimos conferir esta folha.</b> '+escapeHTML(x.semAnalise)+
         '. Seguimos com o preço de tabela — se quiser a nota e o desconto, exporte a mesma '+
         'folha em <b>PNG</b>, que a conferência é bem mais leve.</div>'
       : '';
-    return '<div class="rep"><div class="l1"><b>'+
+    return '<div class="rep" data-folha="'+i+'"><div class="l1"><b>'+
       (folhas.length>1? (i+1)+'. ':'')+escapeHTML(x.f.name)+'</b>'+
       '<span style="color:var(--fraco);font-size:10.5px">'+fmt(x.f.size)+'</span>'+
       '<button data-rmf="'+i+'">×</button></div>'+

web/site-upload.js

@@ -84,7 +84,7 @@ function sel(fs){
           let mostrado=0;
           previaPngGrande(x.f, 600, p=>{
             const pct=60+Math.floor(p*38);
-            if(pct-mostrado>=3){ mostrado=pct; x.pct=pct; pintaFolha(); }
+            if(pct-mostrado>=1){ mostrado=pct; x.pct=pct; pintaProgressoFolha(x); }
           }).then(cv=>{
             if(cv && folhas.includes(x)){
               x.previewSrc=cv.toDataURL('image/webp',0.85);

web/site-v2.css

@@ -318,3 +318,16 @@ html:is([data-rota="pagamento"],[data-rota="pix"]) .pagGrid{display:grid;grid-te
 @media (max-width:480px){
   .etapas2 .w{grid-template-columns:1fr}
 }
+
+/* Skeleton placeholders where the page really waits */
+.skel{position:relative;border-radius:8px;background:linear-gradient(90deg,#EEEFF1 25%,#F7F7F8 37%,#EEEFF1 63%);background-size:400% 100%;animation:skel 1.4s ease infinite}
+@keyframes skel{0%{background-position:100% 50%}100%{background-position:0 50%}}
+@media (prefers-reduced-motion:reduce){.skel{animation:none}}
+.folhaSkel{display:flex;align-items:center;justify-content:center;max-height:520px;min-height:180px;width:100%}
+.folhaSkel span{font-size:12.5px;color:var(--fraco);background:#fffc;padding:4px 10px;border-radius:999px}
+#vArea .folhaPilha{display:flex;flex-direction:column;gap:4px;max-height:520px;overflow:auto;background:#fff}
+#vArea .folhaPilha img{width:100%;height:auto;display:block}
+.folhaMais{font-size:12px;color:var(--texto2);text-align:center;padding:8px}
+.skelLinha{height:14px;margin:8px 0}
+.skelLinha.curta{width:40%}
+.skelBloco{height:160px;margin-top:8px}