// collect — frontend

const $  = (id) => document.getElementById(id);
const log = (msg) => {
  const el = $("log");
  if (!el) return;
  const now = new Date().toISOString().replace("T"," ").replace("Z","");
  el.textContent += `[${now}] ${msg}\n`;
  el.scrollTop = el.scrollHeight;
};

let CFG = null;
let RATES = null;
let CURRENT_QUOTE = null;
let CURRENT_TX = null;
let SELECTED_ACCOUNT = null;

// ===== utils =====
function bytesHuman(n=0){
  const u = ["B","KB","MB","GB","TB"];
  let i = 0; let v = Number(n||0);
  while (v >= 1024 && i < u.length-1){ v/=1024; i++; }
  return `${v.toFixed(i?2:0)} ${u[i]}`;
}
function middleEllipsis(s="", keep=6){
  s = String(s); if (s.length <= keep*2) return s;
  return `${s.slice(0,keep)}…${s.slice(-keep)}`;
}
async function api(path, opt={}){
  const res = await fetch(path, { ...opt, headers: { "content-type":"application/json", ...(opt.headers||{}) }});
  if (!res.ok) throw new Error(`${path} ${res.status}`);
  return res.json();
}
function isImageFilename(name = "") {
  const n = name.toLowerCase();
  return n.endsWith(".png") || n.endsWith(".jpg") || n.endsWith(".jpeg") ||
         n.endsWith(".gif") || n.endsWith(".webp") || n.endsWith(".bmp") ||
         n.endsWith(".svg");
}
function ipfsUrlFromPath(path) {
  if (!path) return "";
  const gw = (CFG && CFG.gateway) ? CFG.gateway.replace(/\/+$/,"") : "";
  return gw ? `${gw}${path}` : path;
}

// ===== wallet UI =====
function updateWalletUI() {
  const btn = $("btnConnectTop");
  const acctEl = $("tbAcct");
  if (!btn || !acctEl) return;

  if (!SELECTED_ACCOUNT) {
    btn.disabled = !window.ethereum;
    btn.textContent = window.ethereum ? "MetaMask Login" : "No MetaMask";
    acctEl.textContent = "wallet: not connected";
  } else {
    btn.disabled = false;
    btn.textContent = "MetaMask Logout";
    acctEl.textContent = `wallet: ${SELECTED_ACCOUNT}`;
  }
}

$("btnConnectTop").addEventListener("click", async () => {
  try {
    if (!window.ethereum) { updateWalletUI(); return; }
    if (!SELECTED_ACCOUNT) {
      const accounts = await ethereum.request({ method: "eth_requestAccounts" });
      SELECTED_ACCOUNT = (accounts && accounts[0]) ? accounts[0] : null;
      log(`✅ Login ${SELECTED_ACCOUNT || "(none)"}`);
      updateWalletUI();
      if (SELECTED_ACCOUNT) await loadFiles();
    } else {
      log("👋 Logout");
      SELECTED_ACCOUNT = null;
      CURRENT_QUOTE = null;
      CURRENT_TX = null;
      updateWalletUI();
      await loadFiles();
    }
  } catch (e) {
    log(`wallet toggle error: ${e.message}`);
  }
});

// ===== config & health & rates =====
async function loadConfigAndHealth(){
  CFG = await api("/api/config/public");
  $("cfgChain").textContent = CFG.chain || "–";
  $("cfgRpc").textContent   = CFG.rpc || "–";
  $("cfgPayTo").textContent = CFG.payTo || "–";
  $("cfgGateway").textContent = CFG.gateway || "–";
  $("cfgTier").textContent  = (CFG.tierBytes ? `${Math.round(CFG.tierBytes/1024/1024)} MB` : "–");
  $("cfgPpt").textContent   = (CFG.priceEgazPerTier ? `${CFG.priceEgazPerTier} ${CFG.currencyBase||"EGAZ"}` : "–");
  $("cfgConf").textContent  = CFG.requiredConfirmations ?? "–";

  const h = await api("/api/health");
  $("healthBlock").textContent = h.latestBlock ?? "–";
  $("healthReq").textContent   = h.requiredConfirmations ?? "–";
  $("healthNow").textContent   = h.now ?? "–";

  try{
    RATES = await api("/api/rates");
    $("rateSrc").textContent = RATES.source || "fallback";
    $("rateEgazUsd").textContent = RATES.egazUsd ? `$${RATES.egazUsd}` : "–";
    $("rateEtiUsd").textContent  = RATES.etiUsd  ? `$${RATES.etiUsd}`  : "–";
    $("rateEtiPerEgaz").textContent = RATES.etiPerEgaz ? `${RATES.etiPerEgaz.toFixed(6)} ETI` : "–";
    log(`Rates src=${RATES.source||"?"} egazUsd=${RATES.egazUsd||0} etiUsd=${RATES.etiUsd||0}`);
  }catch(e){
    $("rateSrc").textContent = "unavailable";
    $("rateEgazUsd").textContent = "–";
    $("rateEtiUsd").textContent  = "–";
    $("rateEtiPerEgaz").textContent = "–";
    log(`rates error: ${e.message}`);
  }
}

// ===== files =====
async function loadFiles(){
  const status = $("filesStatus");
  try{
    status.textContent = "loading…";
    const addr = SELECTED_ACCOUNT || "0x0000000000000000000000000000000000000000";
    const res = await api(`/api/files?address=${addr}`);
    const files = res.files || [];
    renderFiles(files);
    renderGallery(files);
    status.textContent = `showing ${files.length} file(s) for ${middleEllipsis(addr)}`;
    // recent preview
    const recent = files[0];
    const box = $("recentBox");
    const who = $("recentFor");
    who.textContent = `Showing files for ${middleEllipsis(addr)}`;
    if (!recent){ box.textContent = "No preview"; return; }
    const href = ipfsUrlFromPath(recent.path || "");
    if (href && isImageFilename(recent.filename||"")){
      box.innerHTML = `<a href="${href}" target="_blank" rel="noopener"><img src="${href}" alt=""></a>`;
    } else {
      box.innerHTML = `<a href="${href}" target="_blank" rel="noopener" class="small" style="color:#98a2b3">${recent.filename||"file"}</a>`;
    }
  }catch(e){
    status.textContent = `error: ${e.message}`;
    renderFiles([]);
    renderGallery([]);
  }
}

function renderFiles(files){
  const wrap = $("filesTableWrap");
  const empty = $("filesEmpty");
  const tbody = $("filesTbody");
  tbody.innerHTML = "";
  if (!files || files.length === 0){
    empty.classList.remove("hidden");
    wrap.classList.add("hidden");
    return;
  }
  empty.classList.add("hidden");
  wrap.classList.remove("hidden");
  for (const f of files){
    const tr = document.createElement("tr");
    const size = f.size_bytes ?? f.sizeBytes ?? 0;
    const cid  = f.cid || "";
    const path = f.path || "";
    const label = f.label || "";
    const when = f.created_at || f.createdAt || "";
    const status = f.status || "stored";
    tr.innerHTML = `
      <td>${f.filename || "—"}</td>
      <td>${bytesHuman(size)}</td>
      <td class="mono small">${cid || "—"}</td>
      <td class="mono small">${path || "—"}</td>
      <td>${label || "—"}</td>
      <td><span class="tag">${status}</span></td>
      <td class="small">${when ? new Date(when).toLocaleString() : "—"}</td>
    `;
    tbody.appendChild(tr);
  }
}

function renderGallery(files){
  const wrap = $("gallery");
  const status = $("galleryStatus");
  wrap.innerHTML = "";
  if (!files || files.length === 0){
    status.textContent = "No files yet.";
    return;
  }
  status.textContent = `Showing ${files.length} file(s).`;

  for (const f of files){
    const card = document.createElement("div");
    card.className = "card-thumb";

    const head = document.createElement("div");
    head.className = "small";
    head.style.display = "flex";
    head.style.justifyContent = "space-between";
    head.style.gap = "8px";
    head.innerHTML = `
      <span class="mono" style="overflow:hidden;text-overflow:ellipsis;white-space:nowrap;max-width:70%;">${f.filename || "—"}</span>
      <span class="tag">${(f.currency || "EGAZ").toUpperCase()}</span>
    `;

    const media = document.createElement("div");
    media.className = "thumb-box";

    const link = document.createElement("a");
    const href = ipfsUrlFromPath(f.path || "");
    link.href = href || "#";
    link.target = "_blank";
    link.rel = "noopener";

    if (href && isImageFilename(f.filename || "")) {
      const img = document.createElement("img");
      img.src = href;
      img.alt = f.filename || "image";
      img.loading = "lazy";
      img.onerror = () => {
        media.innerHTML = `<div class="small" style="color:#98a2b3;text-align:center;padding:12px;">
          Preview unavailable<br/><span class="mono">${(f.path||"").slice(0,40)}…</span>
        </div>`;
      };
      link.appendChild(img);
    } else {
      link.innerHTML = `<div class="small" style="color:#98a2b3;text-align:center;padding:12px;">
        No preview<br/><span class="mono">${(f.path||"").slice(0,40)}…</span>
      </div>`;
    }
    media.appendChild(link);

    const foot = document.createElement("div");
    foot.className = "small";
    foot.style.display = "flex";
    foot.style.justifyContent = "space-between";
    const size = f.size_bytes ?? f.sizeBytes ?? 0;
    const when = f.created_at || f.createdAt || "";
    foot.innerHTML = `
      <span>${bytesHuman(size)}</span>
      <span>${when ? new Date(when).toLocaleString() : ""}</span>
    `;

    card.appendChild(head);
    card.appendChild(media);
    card.appendChild(foot);
    wrap.appendChild(card);
  }
}

// ===== wallet ensure =====
async function ensureWallet(){
  updateWalletUI();

  if (!window.ethereum) return;

  const accts = await ethereum.request({ method: "eth_accounts" });
  SELECTED_ACCOUNT = (accts && accts[0]) ? accts[0] : null;
  updateWalletUI();

  ethereum.removeAllListeners?.("accountsChanged");
  ethereum.on?.("accountsChanged", async (accounts) => {
    SELECTED_ACCOUNT = (accounts && accounts[0]) ? accounts[0] : null;
    updateWalletUI();
    await loadFiles();
  });

  ethereum.removeAllListeners?.("chainChanged");
  ethereum.on?.("chainChanged", async (_chainId) => {
    await loadConfigAndHealth();
    await loadFiles();
  });
}

// ===== init =====
(async function init(){
  try{
    updateWalletUI();              // immediate correct button label
    await loadConfigAndHealth();
    await ensureWallet();
    await loadFiles();
  }catch(e){
    log(`init error: ${e.message}`);
  }
})();